3. Table of ContentsTABLE OF
CONTENTS
PREFACE ………………………………………………………………....
FOREWORD ………………………………………………………………
INTRODUCTION ………………………………………………………
PLANT MORPHOLOGY ………………………………………………
CLIMATIC FACTORS AND THEIR INFLUENCE ON TOMATOES…….
GREENHOUSES FOR TOMATO PRODUCTION ……………………….
NET HOUSES FOR TOMATO PRODUCTION …………………………..
GREENHOUSE COVERING FILMS…………………………………
PREPARATION FOR NEW CROP…………………………………
IMPROVING CLIMATE CONDITIONS IN SUMMER AND AUTUMN……
SEEDS, SEEDLING PREPARATION AND TRANSPLANTING…………
TRAINING METHODS………………………………………………………
PLANTING SEASONS………………………………………………………
TABLE TOMATO VARIETIES………………………………………
CHERRY TOMATO VARIETIES………………………………………
GROWING TOMATOES FOR CLUSTER HARVESTING…………………
NEW TOMATO PRODUCTS…………………………………………………
PARTIAL RESISTANCE TO ROOT KNOT NEMATODES…………………
ROOTSTOCK AND GRAFTING……………………………………………
POLLINATION AND FRUIT SET OF GREENHOUSE TOMATOES……
IRRIGATION AND NUTRITION……………………………………………
MICROELEMENT DEFICIENCY IN TOMATO PLANTS……………………
SOIL SALINITY…………………………………………………………………
GROWING TOMATOES IN SUBSTRATES (Soilless Culture)…………
RECYCLING DRAINAGE WATER ………………………………………….
GREENHOUSE VENTILATION………………………………………
GREENHOUSE HEATING……………………………………………
CO2 ENRICHMENT FOR TOMATOES…………………………………
ETHYLENE DAMAGE………………………………………………………
GROWTH AND FRUIT DISORDERS………………………………………
TOMATO HARVESTING AND POSTHARVEST…………………………
ETHERAL TREATMENT TO ACCELERATE TOMATO RIPENING……
OVER VIEW OF ORGANIC PRODUCTION OF TOMATOES…………
DISEASE AND PEST CONTROL……………………………………………
CHEMICAL SPRAY APPLICATION TECHNOLOGIES…………………
NON-PARASITIC DISORDERS………………………………………
WEEDS AND PARASITIC PLANTS………………………………………
SOIL-BORNE DISEASES……………………………………………
TOMATO LEAF DISEASES……………………………………………
BACTERIAL DISEASES……………………………………………
VIRAL DISEASES…………………………………………………………
PESTS……………………………………………………………………
BIBLIOGRAPHY……………………………………………………………
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5. PrefacePREFACE
High-quality vegetable production, particularly tomatoes, holds an
important part in the global fresh horticultural food basket. We therefore
feel the need to transfer and adapt the knowledge and technology that
has been compiled in this field in Israel and make it available to English-
speaking agricultural extensionists, specialists, growers and entrepreneurs.
Tomato production has special relevance to the Mediterranean and
Middle East countries. The compilation of this publication can be used
as professional input for the regional Middle East and Mediterranean
Program of Integrated Crop Management initiated by the Peres Center
for Peace in cooperation with countries in the region. Tomato production
and post-harvest care are a priority in the activities of its cooperation
programs.
The newly published publication, Tomato Production Under Protected
Conditions, was written by Mr. Omar Zeidan, Director, Vegetable Growing
Department and Assistant Deputy-Director of the Extension Service,
Ministry of Agriculture and Rural Development, in 2001.
Mr. Zeidan is also recognized as a highly experienced tomato specialist
in international circles.
This manual was translated from the original Hebrew document of the
Extension Service of the Israel Ministry of Agriculture and Rural
Development. The professional strength and relevancy of the topic
motivated and initiated the parties, MASHAV, CINADCO and the Peres
Center for Peace, through the Andreas Agricultural Development Trust,
to publish the manual in its English version.
The publishers wish to acknowledge and thank the Extension Service
of the Israel Ministry of Agriculture and Rural Development for their
professional contribution and cooperation in this endeavour.
We envisage that this publication will contribute to the production of high-
quality produce resulting in increased farm income and economic growth.
We also hope that Tomato Production Under Protected Conditions will
enhance the sharing of know-how as a means of strengthening the
professional and people-to-people links of the countries in the region
and beyond.
i
Zvi Herman
Director
CINADCO
Ministry of Agriculture and
Rural Development
Prof. Samuel Pohoryles
Director
The Andreas Agricultural
Development Trust
The Peres Center for Peace
Moshe Goren
Director
Extension Service
Ministry of Agriculture and
Rural Development
6.
7. ii
ForewordFOREWORD
This manual is intended for professionals and farmers involved in
greenhouse tomato growing and marketing, locally and/or for export.
The manual includes principles of tomato growing in order to help the
growers understand the basic stages that guarantee a successful crop.
The material in this manual is based on technological knowledge and
experience that has been accumulated in Israel over the years for the
better use of greenhouses, nurseries and net houses for tomato production.
The chapters in this manual are written according to the order of stages
recommended in establishing a new greenhouse project and according
to the order of activities in growing tomatoes, from the planning stage
until the final growing stages.
The agro-technical instructions, planting times, fertilization, irrigation,
pollination and other activities are based on numerous research findings
and field tests that were conducted at various sites throughout Israel.
Research institutions, scientists, extension workers and growers
participated in and contributed to the establishment of this advanced
agro-technological branch.
Thus, this manual includes professional and scientific principles that can
provide basic training for students, support for field extension staff and
guidelines for marketers of agricultural output in Israel and in countries
throughout the world that participate in Israel’s international cooperation
programs. We are happy to share the professional material presented
here, however, we wish to point out that these are recommendations
only and should not take the place of detailed and certified local engineering
planning.
It is my pleasure to thank CINADCO, The Centre for International
Agricultural Development Cooperation of the Ministry of Foreign Affairs
and the Ministry of Agriculture and Rural Development, the Peres Center
for Peace, through the Andreas Agricultural Development Trust and the
many experts and professional staff of the Israel Ministry of Agriculture
and Rural Development, Extension Service, who read the draft of this
manual and submitted their helpful comments in order to make this
publication possible.
Director, Vegetable Growing Dept. and Deputy Director, Extension Service,
Ministry of Agriculture and Rural Development
Omar Zeidan
8.
9. 1
Common name: Tomato
Scientific name: Lycopersicon esculentum Mill.
Family: Solanaceae
The tomato plant originated in Peru and Mexico, in present day Central
and South America. The tomato reached Europe from Mexico in the 16th
Century, and was initially used as an ornamental plant. At the end of
the 18th Century, the tomato started to be produced as an edible cultivated
plant for household use. The tomato only reached Israel in the 19th
Century.
Tomato production is currently considered to be one of the main vegetable
crops, and constitutes an economic force that influences the income of
many growers in the world.
In Israel, tomatoes used to be planted in greenhouses in the fall, especially
in the western Negev desert, with the aim of developing tomato production
for export to Europe and other destinations. This crop was characterized
by a limited yield season from December to March. However, technological
developments and innovative growing methods expanded crop production
to other areas in Israel and is now year round in greenhouses and net-
houses.
Contamination of open-field tomato plants by tomato yellow leaf curl
virus (TYLCV) requires intensive and multiple spraying against Bemisia
tabaci (whitefly). This encouraged transition to growing of tomatoes
under protected conditions, in both greenhouses and net houses.
The conventional production methods in Israel, which are described in
this booklet, are similar to conventional methods applied in many
Mediterranean and Latin American countries. Therefore, the
recommendations in this booklet may be useful for growers in these
countries.
Export of regular tomatoes from Israel has recently declined, due to the
large supply of tomatoes in international markets from supply sources
that are close to the European markets, such as Spain, Morocco and
other Mediterranean countries.
Since tomato production targeted for the export market is a source of
livelihood for many farmers, in order to remain competitive, they must
produce high quality tomatoes with unique and marketable characteristics.
Following the decline in demand for regular tomatoes, two innovative
products were developed: cherry tomatoes and cluster tomatoes, both
of a very high quality, for export to European and USA markets. Other
tomato products such as cluster cherry tomatoes and extra-sweet
tomatoes grown in brackish water have also been developed, but on a
smaller scale.
Continuous research, the breeding of new varieties, as well as the
development and implementation of innovative agro-technical methods,
are a guarantee for continued production and supply of tomatoes for
local consumption and export, and in the future will enable the growers
to maintain their competitive status.
INTRODUCTION1.
10. 2. PLANT MORPHOLOGY
Leaves: In most varieties, the leaves consist of two
pairs of serrated leaflets and a terminal leaflet. Small
secondary leaflets develop between the leaflets. The
leaves of the tomato plant, like the stem, are covered with
fine hairs.
Inflorescence: Inflorescence appears on the main stem
and lateral branches. The number of flowers per
inflorescence is determined according to the varieties and
growing conditions. Varieties with a small fruit (cherry
tomatoes) have 50 and more flowers per inflorescence.
Varieties with a regular-sized fruit usually have between 4
and 10 flowers per inflorescence in optimal conditions.
However when flowering begins and temperatures are very
high, there may be fewer flowers per inflorescence. On the
other hand, when temperatures are low, there are more
flowers per inflorescence.
2
Growth habits of tomato plants:
Determinate growth: These tomato plants are relatively
compact and grow to a certain height. They flower and
set all their fruit within a short time. The main stem and
lateral branches terminate in two consecutive inflorescences
after a number of nodes, according to variety. In these
varieties, the number of inflorescences per stem is not
fixed. Determinate varieties can be grown in open fields,
spread out over beds or trellised on sticks, if the varieties
have a strong growth.
Indeterminate growth: Indeterminate tomato plants
grow continuously, producing flowers and fruit over a long
period of time until the grower or weather conditions
terminate the crop. The main stem and lateral branches
continue to grow and the number of leaves between
inflorescences is more or less fixed.
In these varieties, the inflorescences appear with a set
number of leaves between the inflorescences on the main
stem and lateral branches. Indeterminate varieties can
be grown on trellises in open fields and greenhouses, and
the plant is shaped by pruning the lateral branches.
Roots:
Development of the tomato plant’s root system depends
on the growing method, type of soil and irrigation regime.
In soil-less culture, roots develop according to the size
and shape of the growing container. The root system in
light soil is not as deep as the root system in medium-
heavy soil. Plants that are grown directly from seed
develop a denser root system than plants that are
propagated or prepared in a nursery. When unrestricted
by disease or soil type, tomato roots can reach a depth
of 1.5 to 2 meters. However, the active part of the root
system is not as deep. Under high humidity conditions,
adventitious roots may develop together with the natural
root system, but these roots do not contribute to plant
development.
Stems:
The growing shape, number and lengths of stems differ
according to the varieties and growing methods. Sympodial
growth in tomatoes is characterized by a main stem that
terminates with inflorescence after the appearance of a
certain number of leaves and nodes.
A lateral branch grows from a lateral bud, and again a
number of leaves, nodes and inflorescences develop, and
so on.
Table 1. Number of leaves below first
inflorescence and number of leaves
between inflorescences on the main
stem
DeterminateIndeterminate
Below first
inflorescence
Between first
& second
inflorescence
Third and more
inflorescence
6-14
3-5
3
6-14
2-3
0-1-2
Temperature has a significant effect on the timing and
position of the first and second inflorescence on the main
stem in relation to the number of leaves. When the
temperature is high, appearance of the first inflorescence
tends to be delayed. There are many leaves below the
first and the second inflorescence. When the temperature
is low, the number of leaves below the first inflorescence
decreases and there are only a few leaves on the main
stem below the flowering.
11. Fruit:
Mature tomato fruits are mainly red. However some
varieties have fruit of a different color: pink, orange and
yellow. The fruit is succulent and its shape varies according
to variety and can be: globe, flattened globe, deep globe,
flat or ribbed. The size of the fruit also varies according
to variety: fruit of cherry varieties weigh between 8 and
20 grams, and large fruit varieties weigh up to 250 grams.
Hereditary factors usually directly influence the size and
shape of the fruit. However growing conditions and position
of inflorescence on the plant also influence the growth
and weight of the fruit.
The tomato fruit can be characterized according to the
number of locules (carpels): round, small and medium-
sized fruit usually have two or three locules while flat and
large fruit have about ten to twelve locules.
Descriptions of tomato fruit include fruit with green shoulders
(U+), and fruit without green shoulders (uniform = U).
The absence or presence of green shoulders is a genetic
factor. Direct exposure to sunlight of a green shouldered
fruit deepens the green color and can even turn it to yellow.
The foliage cover is the most effective way to reduce this
phenomenon.
Tomato fruit is defined as a joint fruit with an abscission
point on the peduncle.
Most fresh market fruits are picked with the calyx. When
the fruit pedicel has no abscission point it is defined as
jointless. Joint varieties are used when growing processing
tomatoes because the fruits separate easily from the calyx.
On the other hand fruits of fresh market cluster tomatoes
are often jointless but are attached more firmly to the
clayx.
Flower:
The flower is usually composed of six green sepals, six
yellow petals and six stamens. The pistil is composed of
an ovary, a long style and a simple and slightly swollen
stigma. The ovary has between 2 and 20 ovules, shaped
according to variety, and it reflects the shape of the fruit
that will develop.
3
Fruit with many locules
Female parts of tomato flower
Natural tomato flower
Fruit with 3 locules
12. Changes in the fruit during ripening stages
After the fruit has reached the mature green stage, rapid
changes start to occur in the fruits. The chlorophyll gradually
disappears, and at the same time, other pigments are
created in the fruit, especially lycopene and b carotene.
The b carotene concentration reaches a maximum level
in the initial ripening stages, while the lycopene level
increases as ripening nears completion, and even later.
The estimated time from the mature green stage to full
ripening of the fruit (90%) is about ten days. There are no
significant changes in vitamin C level and total soluble
solids (TSS) during the ripening process, although in
varieties with a smaller fruit, sugar continues to accumulate
in the advanced ripening stages. Aroma and flavor
compounds also increase during the ripening process.
However in this process the fruit is less firm, and its tolerance
to cracking and sunburn increases. A red fruit is less
damaged by sun. However when a green fruit is suddenly
exposed to sun, it is severely damaged and the damage
is apparent when the fruit is still green and also when it
turns red. The pH level also decreases gradually during
the final ripening stages, due to the increase of citric and
malic acids. Temperatures affect development of the tomato
color: lycopene, which gives the tomato its red color, is not
produced at temperatures over 30ºC. However production
of ß carotene, which gives the tomato its yellow color,
continues. Production of ß carotene stops in temperatures
over 40ºC. The best color of tomato fruits is produced at
optimum temperatures between 20-24ºC.
Firmness and shelf life
Firmness and shelf life are characteristics of high quality
tomato varieties, which are required for long distance
transport for both local and export markets. The most
significant method for acquiring firmness and shelf life is
by breeding and developing varieties with firmness. The
great success in acquiring this characteristic has been
reinforced by Israeli geneticists who successfully introduced
ripening-inhibitor genes into new hybrids. Amongst the
genes known to inhibit ripening are the RIN and the NOR
genes. Varieties heterozygous to the RIN gene (+/RIN)
usually have a shelf life that is 20 - 50% longer than regular
varieties, and varieties heterozygous to the NOR gene
(+/NOR) have a longer shelf life, exceeding regular varieties
by 50 - 100%. It is important to remember that fruit from
varieties that have the NOR gene should be picked when
pink or even more mature. Fruit picked before this stage
will not develop the proper red color and the quality of the
taste will be lowered.
Flavor
The flavor of tomatoes is influenced by the compounds of
the fruit and the ratio between them. The tomato fruit is
mostly water, with solids constituting only 5-7% of the fruit.
About 50% of the solids are sugars (mainly fructose and
glucose), and about 12% are organic acids (malic and
citric acids).
The tomato fruit includes other compounds in small
quantities, such as minerals (K, Ca, Mg, P), proteins,
pectic substances, pigments, amino acids, volatiles,
vitamins, ascorbic acids and polyphenols. All these
compounds affect the flavor and aroma of the tomatoes.
In general, aroma and taste can be influenced by
breeding/genetics.Agrotechnical activities also significantly
influence improved taste.
7
Changes graph
4
Development of ripening
Green mature
13. 3
Temperature has a significant influence on the tomato
plant’s fertility and directly affects both yield and product
quality. There are extreme disorders in the tomato plant’s
fertility in winter, when day and night temperatures are
low - below 18ºC and 10ºC respectively - and in summer,
when the day and night temperatures are high - above
32ºC and 22ºC respectively.
The morphological and physiological changes in the tomato
plant, which are affected by temperature, are described
here:
Temperature
Temperature is the main climatic factor which influences
most of the tomato plant’s development stages. The optimal
temperature for growing tomatoes is between 22ºC and
26ºC during the day, and between 14ºC and 17ºC at night.
Extreme temperature fluctuations may damage the tomato
in the different growing stages.
5
CLIMATIC FACTORS AND
THEIR INFLUENCE ON TOMATOES
Table 2a. The tomato plant’s temperature requirements in the different growing stages
Exposure to high temperature:
Reduction of pollen viability and quantity in the flowers
Reduction of number of flowers in inflorescence
Appearance of poor and weak inflorescences
Distortion of the anthers
Elongation of the style beyond the anther
Asymmetry in the inflorescence shape
Delay in appearance of first inflorescence on the main stem
Morphological changes - elongation of the plant’s internodes
Minimum
(ºC)
Germination
Growth
Fruit set at night
Fruit set in the day
Production of red pigment - lycopene
Production of yellow pigment - ß carotene
Chilling injury
Frost (freezing)
Storage of pink and red fruit
Growing stage Optimum
(ºC)
11
18
10
18
10
10
16-29
21-24
14-17
23-26
20-24
21-23
6
for some hours
(-2)-(-1)
10-12
34
32
22
32
30
40
Maximum
(ºC)
Elongation of the style beyond
the anthers Asymmetry in inflorescenceFew flowers in inflorescence
Effect of high temperature
14. Radiation and daylight
Increased radiation intensity stimulates vegetative growth
and results in higher yields, mainly due to increased
assimilation and production of dry matter. In many plants,
the growth rate in the dry weight per area unit is influenced
Continuous exposure to low temperature:
Reduction of pollen viability and quantity
Distortion of ovary and increased incidence of fruit
deformation
Elongation of the ovary
Distortion of the stamen
Increased number of flowers in inflorescence
Short internodes and compact plants
Relative humidity
Relative humidity of 65% to 85% is beneficial to the
development of the tomato plant. This is expressed in
optimal growth and fertility. Higher relative humidity results
in irregular release of pollen grains from the anthers and
unsatisfactory distribution on the stigma. High relative
humidity also creates conditions for development of various
leaf diseases, such as late blight, caused by Phytophthora
infestans, Botrytis, and Erwinia.
Incidence of blotchy ripening increases in high humidity.
On the other hand, in relative low humidity, there may be
low fertility as the pollen grains dry out on the stigma even
6
The data in the table clearly indicate the damage to the
fruit and fruit quality caused by excessive shading, which
results in insufficient radiation.
by radiation, more than by any other environmental factor.
A positive correlation was found between this rate and
radiation intensity. When examining the assimilation rate
of tomato plants, it was found that the lowest assimilation
rate was recorded at low radiation intensity in December
(Israel), approaching the shortest day of the year, while
the maximum assimilation rate was recorded at high
radiation intensity in summer. In winter, the photosynthetic
radiation quantity is the principal factor that determines
growth rate, while in summer, the radiation intensity is
usually sufficient, and growth may be restricted by other
factors.
Tomato plants are usually indifferent to daylight hours and
photoperiod, however when the radiation intensity is low,
there is a negative influence on the plants and on the yield
components, as a result of lack of radiation in greenhouses
during the winter months. The yield and its quality are
severely damaged by artificial shading or excessive
accumulation of dust on the external covering sheets,
which reduce the quantity and intensity of the radiation
penetrating into the greenhouses.
In an experiment conducted in the Besor experimental
station in Israel’s southern desert, a significant reduction
in the number of fruit in inflorescence and ripening
percentage was found with 12, 34 and 55 % shading of
light intensity (according to A. Sagie). Shading was also
found to have a negative influence on the percentage of
hollow (puffy) and blotchy fruit.
Table 2b. Influence of shading on
fertility and ripening of tomatoes in
the Besor experimental station
Percentage of
undeveloped
fruit set
Shading
percentage
Fruit in
inflorescence
Number of
flowers in
inflorescence
Number of
flowers in
inflorescence
12
34
55
10.0
10.4
9.0
7.1
6.7
5.6
71.0
66.0
63.0
29.0
32.0
41.0
Elongated fruit (Lemon shape) – low temperature
Short internodes, distortion and
cracks in stem - low temperature
Deformations with cat face – low temperature
15. 4 GREENHOUSES FOR
TOMATO
PRODUCTION
Growing tomatoes in greenhouses is a means to isolate
plants from the environment, allowing growing conditions
that are suitable for development of the plant and production
of a high quality and quantity yield.
In greenhouse production, tomato plants are grown on a
single stem or two stems per plant, according to the variety
and season. In this method, the plants grow vertically on
strings or trellises and are arranged in single or double
rows on the beds. In order to achieve a maximum yield,
technologies should be adapted to the growing conditions.
Some important considerations are the shape and position
of the structure, covering material, insect-proof nets,
heating and cooling methods and a large range of
accessories. These technologies enable production under
optimum conditions, or improved conditions.
When planning the greenhouse, the distance between
the greenhouse units should be considered, so as to allow
efficient ventilation for the regulation of temperature and
humidity. Additional things to consider are how to optimize
the workers’ time when moving among the structures and
the convenience entailed when performing agro-technical
tasks, such as cultivation, harvest and spraying. The
greenhouse design should facilitate transportation of the
produce from the greenhouse to the packing house.
Advantages of greenhouse production
1. Protection from harsh climatic conditions
Rain and hail
Low temperature
Winds and Storms
Dew and excess humidity
2. Control over climatic factors
Heating
Cooling
Shading
CO2 enrichment
3. Adaptation of production and marketing to local and
export market requirements
Production during different growing seasons
Production and marketing over an extended period
Continuous supply
4. Savings in production costs
Increased yield per unit
Increased efficiency of agricultural inputs
7
Convenient operation
5. Decreased use of pesticides
Use of nets and films to keep out insects
6. Improved product quality
Use of quality varieties
Uniform fruit shape, color and size
Use of varieties with a long shelf life
Characteristics
1. Agreenhouse for growing tomatoes should be designed
to hold a vertical load of 35 kg/m2.
2. The greenhouse should be planned and approved by
an authorized engineer.
3. The building materials should be durable: concrete,
galvanized steel, wood treated by impregnation, welding
after galvanization coated with zinc-rich paint. The
screws should be galvanized and vibration-resistant
4. The gutter direction should be north-south, to allow
maximum penetration of light and minimum shade on
the plants throughout the day.
5. If the greenhouse does not have roof vents, its length
(gutters) should be limited to 36 - 40 m. The width,
which is composed of the gable spans, is unlimited.
6. If the greenhouse has roof vents, its length and width
is not limited.
7. The gutter height required for producing tomatoes on
trellises over a long yielding period is at least 4 m.
8. There should be a distance of 10 to 12 m, or at least
the equivalent of twice the structure height, between
nearby greenhouses.
9. The greenhouse should be able to withstand winds of
150 km/h, and it should have a life span of at least ten
years.
10. It is recommended to install porches around the
greenhouse to reinforce its resistance to strong winds.
11. The greenhouse should be constructed on a 0.5%-1%
linear and lateral slope, for efficient drainage of
rain and in soilless culture for the surplus irrigation
water.
12. There should be accessible approaches to and from
the greenhouse for passage of agricultural equipment
and convenient transport and removal of fruit.
Notes:
A. These principles are suitable for the conditions in Israel
and for countries with a similar climate. There are other
greenhouse models which are compatible with local
conditions, such as in Almeria, Spain.
B. The above information relates only to polyhouses.
Essential accessories
1. Roll-up curtains on each wall. The curtains on the long
side should be divided into two or more sections.
2. Double entrances for convenient movement of produce.
3. Preparation for connection of an insect-proof net by
installing horizontal beams on the wall at a suitable
height. It is recommended to install insect-proof nets
at all openings to ensure complete sealing of the
greenhouse.
before germination. This results in partially fertilized,
small, deformed and hollow (puffy) fruit. At relatively low
humidity and high temperature, there is a high and rapid
evaporation rate of water from the leaves. In these
conditions, the root system cannot supply the water volume
required for evaporation via the leaves, and in extreme
cases, this may lead to partial wilting of the plant growing
tip and increase of blossom end rot, which stems from a
shortage of calcium (Ca) in the fruit tissue. It was found
that excessive humidity in the greenhouses may reduce
evaporation from the leaves, inducing root pressure on
the fruit. This increases incidence of fruit cracking.
16. Span width
Greenhouses have different span widths. The type of
covering greatly influences the span width when planning
the greenhouse. For example, when a rigid covering is
used, greenhouses can have a span width of 9 or even
12 meters. In this case, there will be fewer gutters per
hectare, and there will, of course, be less shading on the
plants. When a flexible covering such as plastic
polyethylene sheets is used, the greenhouse should have
a span width of 6 to 8 m. Plastic coverings are sensitive
to climatic conditions and are susceptible to tearing. For
example, in very hot weather, the sheets become too
slack and their grip on the frame is reduced. The sheets
may also be damaged and tear during storms.
An important consideration is that damage to the sheets
may be partial, and they may be easily repaired or replaced
at a relatively low cost. When the covering is flexible,
the spans are narrower and therefore more gutters are
required, so there is more shading compared to a wide-
span greenhouse.
4. Climate control equipment. The greenhouse should
be prepared for installation of climate-control equipment,
such as heating and air circulation fans, equipment for
applying pesticides and a thermal screen. The position
of the heater should be determined in advance to
enable convenient access for ongoing maintenance
and refueling.
5. Vertical beams should be installed on the greenhouse
walls, perpendicular to the crop rows. A crop wire
runs from wall to wall. Long greenhouses with a path
in the middle should have support poles in the center,
and the crop wire should be divided into two.
6. The crop wires that are parallel to the crop rows
are made of soft galvanized steel, and have a diameter
of 3 - 3.5 mm.
The wires should be stretched between the two beams
at either end of the greenhouse.
7. An infrastructure for soilless culture, recycling of
drainage water and collection of rainwater.
8
Greenhouse roofs
There are many types of greenhouses on the market, with
different span widths and roof models. Some structures
have an even-span roof, which is especially suitable for
rigid covering, such as glass or polycarbonate. Structures
with a gable or arch roof are mainly suitable for plastic
(flexible) coverings. A flexible covering on an arch roof
enables the covering to be firmly attached and properly
stretched, to prevent fluttering. This saves the investment
in a ridged or fixed roof such as glass. Arigid polycarbonate
covering is flexible in a certain direction and it can be
placed on curved roofs. Choice of roof shape will be
adapted to the type of future covering and cost of covering
material. In Israel and the Mediterranean Basin,
polyethylene plastic films are usually used.
Rigid coverings are not common in Mediterranean countries,
for the following reasons:
High cost of construction
The greenhouse frame, especially the roof, would need
to be adapted to rigid covering material
Radiation transmission through these materials (not
glass) could be reduced, as a result of reduced
transparency after a few years.
Diagram of greenhouse
Types of roofs
17. 9
Roof and side ventilation protected by net Roof ventilation protected by netSide ventilation protected by net
Roof vents
Roof, gutter or ridge vents are vents which open along
the length of the span. The hot air, which accumulates
in the greenhouse, rises and is trapped in the upper part
of the greenhouse (in the triangles), where it has a great
influence on the heat load in the greenhouse. A vent
opening in the greenhouse roof releases this heat and
greatly reduces the heat load. Release of heat through
a roof vent in greenhouses with rigid coverings, such as
glass, has been applied for many years in Israel and other
countries. However, in greenhouses with plastic coverings
in Israel, installation of a vent along the span is not an
option, due to the labor required every year to seal the
greenhouse for heating and to keep out insects, which
serve as vectors for viruses.
Developments in the greenhouse industry, the many
manufacturers and the competition between them, have
led to the development of new greenhouse models with
roof vents which are also suitable for plastic coverings. It
is important to install insect-proof nets in the roof vents.
All roof vent models can be opened manually or by a
computer-controlled motor.
Roof vents
18. 5
Net houses for tomato production provide growing
conditions that are similar to those in greenhouses, with
a relatively low investment. Growing in net houses should
begin and terminate in seasons when the climatic conditions
permit it. Therefore, growing should be planned so that
most of the yield is harvested before temperatures drop
and the rainy season begins. If even the lightest rain
penetrates the nets and wets the plants, the fruit will crack,
its quality will drop and in addition, the prevalence of leaf
disease will increase, especially early blight (Alternaria
solani), late blight (Phytophthora infestans) and leaf mold
(Fulvia fulva).
In the Israeli and Mediterranean climate, tomatoes are
planted in net houses in the spring or early summer. In
the rainy season and when humidity is high, the plants
may be severely damaged.
The net house should be completely covered with insect-
proof net (50 mesh), to protect against invasion of insects
and the following specifications should be strictly adhered
to.
NET HOUSES FOR
TOMATO
PRODUCTION
Specifications
1. Net house height: 3.5-4.0 m
2. Recommended unit size: 1 ha
3. Suitable for simultaneous hanging of two nets: 50 mesh
covering and internal shading screen, according to
need
4. Crop wires attached to structure
5. Spaces between poles: 4x4m or 4x6 m
10
6. Double entrance, recommended in the center of the
net house, to allow passage of a tractor for cultivation
and preparation of soil, loading produce and other
agro-technical activities.
7. The net is tied to the structure with 6-8 m straps, and
buried in the ground around the frame.
8. The poles are anchored in the ground.
9. The section of the net that is anchored in the soil and
the lower part of each pole are treated with tar up to
20 cm above ground level.
10.The pole tops are protected with plastic to prevent
friction and tearing of the net.
11. Materials: 2.2 mm thick, hot-dipped galvanized poles
12.Steel cables to withstand 120 km/h winds
13. A gable structure with gutters is preferable to a flat
one.
14. Anchors around the structure are according to the
manufacturer’s specifications, examined and approved
by an authorized party.
15.It is recommended to purchase the structure from an
authorized manufacturer.
Greenhouse covering films isolate the plant from the
external environment, and its properties influence its
relationship with the environment. The most common
coverings are made of plastic materials.
Most of the flexible films used to cover greenhouses are
made of polyethylene (PE). PE has many advantages,
including: light weight, relatively low cost, flexibility,
transparency, easy handling and ability to withstand diverse
climatic conditions.
The properties which are required by films for covering
greenhouses in general and greenhouses for tomato
production in particular, can be divided into two main
categories: mechanical properties, and optical and thermal
properties.
PE covering films with a thickness of about 120 micron
are usually used for one year. Thicker films are used for
more than one year.
Mechanical properties
The mechanical properties are defined in Israeli Standard
821, and relate to sheet strength, tensility (ability to endure
stress), durability, parameters related to dimensions (length,
width, thickness, density), and permitted deviation rate.
UV stabilizer is the main additive in sheets, and is most
important in determining mechanical properties. This
additive provides the sheet with durability and resistance
to radiation ageing and prevents its degradation.
Optical properties
Optical properties have a decisive influence on the yield
level, fruit quality and energy balance in the greenhouse
and the behavior of pests and diseases.
Net house with gable roof
Net house with flat roof
6 GREENHOUSE
COVERING FILMS
21. Soil mulching
Soil mulching with polyethylene sheets is quite common
in the different growing methods, both when growing in
soil, as well as in soilless culture in containers.
Mulching is an agro-technical activity designed for different
objectives, which are influenced by the sheet properties:
Mulching with transparent sheets results in heating of
the upper soil layers and encourages growth, especially
when planting is in low temperatures.
Mulching with black, silver, or black and white PE is
suitable for autumn and spring and prevents germination
of weeds.
Co-extruded mulching, which is black on the bottom
and white on the top, or one white layer contributes to
increasing radiation by reflection to the plants. This
is suitable for northern countries where there is little
radiation in the winter.
In general, mulching creates a climate that is suitable for
growing. When the soil is covered with PE, it has been
found that irrigation efficiency increases and the root
system is more active. Conditions for development of leaf
diseases have also been found to decrease, following
improved microclimate in the greenhouse space by
reducing humidity.
Mulching is applied over the entire span or in strips over
the beds.
With PE mulching, the growers’ awareness of sanitation
increases, and leaves, stems and fruit are easily removed
from between the rows.
The recommended thickness of plastic used for soil
mulching is 40-50 micron.
The diameter of the holes in the plastic should be 8-12
cm. Soil mulching in high temperatures, especially in the
hot summer, increases the temperature under the plastic
and creates negative and poor conditions for rooting and
establishment of the young plants. In high temperatures,
it is recommended to prepare large holes in the mulching
sheets,in order to release the hot air and avoid heating of
the soil.
Soil sterilization
Tomatoes in greenhouses are susceptible to various
diseases, especially soil-borne diseases. These pathogens
can survive in the soil from one season to the next and
moreover, these inoculates (infecting material) can multiply
in the soil to extreme values. As soon as tomatoes, or
any other host plant which is sensitive to these diseases,
are planted, they may be damaged by one or more
pathogens.
Tomato production, which is considered to be expensive,
continues over a number of months and there is no crop
rotation in the greenhouses. Therefore, great effort is
invested to reduce the establishment of pathogens in soils
or growing medium in greenhouses, by performing some
form of sterilization as well as by sanitation treatments
during and at the end of the season.
Here are the main soil-borne pests that may cause damage
to the new tomato crop:
13
Fungal diseases: fusarium wilt and verticillium wilt - most
commercial varieties are resistant to these diseases,
however part of them are resistant to nematodes and to
crown root rot (Fusarium oxysporum f.sp. radicis-
lycopersici); but there is no resistance available for stem
rot (Sclerotinia sclerotiorum), Southern blight (Sclerotium
rolfsii) or Corky root (Pyrenochaeta lycopersici). Since the
genetic sources for resistance to these diseases are limited,
they must be controlled by soil sterilization.
Bacterial diseases: bacterial canker (Clavibacter
corynebacterium michiganensis); bacterial wilt
(Pseudomonas corrugate); soft rot (Erwinia carotovora);
and southern bacterial wilt (Pseudomonas solanacearum)
Viral diseases: mainly tobacco mosaic virus (TMV).
Most varieties are resistant to this disease, except for
some cherry varieties.
Pests: root knot nematode (Meloidogyne spp.), various
soil-borne or airborne pests, some of which are vectors
for viral diseases, such as western flower thrips (Frankliniella
occidentalis)
Parasitic weeds: field dodder (Cuscuta campestris) and
broomrape (Orobanche spp). These weeds are established
in the soil, propagate by seed and germinate with a suitable
host.
Tomato plants are hosts for these parasites, and are
severely damaged when attacked.
Noxious weeds: many types of weeds may reproduce
and germinate in tomato production greenhouses, if there
is no suitable soil sterilization.
Soil sterilization methods
1. Methyl bromide: This is suitable for control of most
pathogens and noxious weeds in the soil and growing
medium, except for viruses and bacteria. Use of methyl
bromide is being phased out according to international
pacts (the Montreal Protocol).
2. Solarization (sun/solar sterilization): Satisfactory
results have been received with soil solarization in
soilless culture. This method is effective in the hot
season.The efficiency of solarization is limited in soils.
3. Metham Sodium: This material is sufficient for control
of various soil fungi and partial control of weeds. It is
very effective in soilless culture for most pathogens.
4. Telodrip inline (Telon with chloropicrin). This
multipurpose liquid fumigant is applied through the
drip irrigation system and covered with PE film. It is
used to control nematodes, fungal soilborne diseases
and certain weeds.
5. Steaming: This method is suitable for control of most
pathogens, including viruses and bacteria. It is suitable
for disinfestations of soilless culture, but is not suitable
for all soils, especially heavy soils.
6. Formalin: This material is suitable for sterilization of
soil or growing media which have been infested by
bacteria.
7. Use of specific pesticides for control of soilborne
pests, as well as specific fungicides, nematicides,
and herbicides.
22. Since innovative sterilization treatments are restricted to
a limited amount of pathogens, it is recommended to
combine a number of sterilization methods according to
need. A combination of methods will ensure better results
than any separate treatment.
Beside the chemical and the physical treatments for soil
sterilization it is recommended to exploit the genetic factor
to reduce damages of soil-born diseases by introducing
the resistance varieties or the use of rootstock in
combination with grafting
Details regarding preparation of soil and sterilization
methods can be found in the manual “Recommendations
for Control of Pests in Vegetables”, published in Hebrew
by the Agricultural Extension Service of the Ministry of
Agriculture and Rural Development, Israel.
Sterilizing the greenhouse space
Greenhouses can be sterilized in the summer. After a
crop has been removed from a greenhouse, the greenhouse
should be sanitized by solar radiation (solarization) by
sealing it hermetically for three to four weeks. Temperatures
in a greenhouse which is sealed in the summer months
reach values which destroy most pathogens in the space
and on the frame of the greenhouse. In order to increase
the sensitivity of pathogens to high temperature, it is
recommended to wet the greenhouse interior and soil once
a week by using a 5-10m3/h micro-sprinkler system. The
greenhouse and soil should be wetted at night or in the
early morning, when temperatures are mild, to prevent
bursts in the irrigation system. Accessories and equipment
that are sensitive to high temperatures and which may be
damaged by the heat should be removed before sealing
the greenhouse.
The greenhouse is sterilized as part of a comprehensive
method and a means for sanitation before planting a new
crop.
Preparing the greenhouse
Before planting, the greenhouse is prepared, covered and
protected against tobacco whitefly, which are vectors for
tomato yellow leaf curl virus (TYLCV). Covering all the
sidewalls with a net keeps these insects out of the
greenhouse. The greenhouse should be hermetically
sealed, especially in the gutter area, to provide maximum
protection against invasion of the pest. A double door
should be installed at the entrance of each greenhouse,
to create a separating passage between the greenhouse
and the environment. The greenhouse film covering
should be thermal IR PE film, with anti-drip additives, both
on the roof as well as on the sidewalls (curtains). The
films should have a thickness of at least 0.12 mm (120
micron). In many cases, the effectiveness of the additive,
which is designed to prevent condensation on the films,
lessens in the second season, and therefore it is not
recommended to use the material for more than one year.
14
Covering the soil before sterilization with methyl bromide
and other chemicals
Covering beds – soil solarization
Covering the substrate containers – soil solarization
23. 8
In order to reduce the heat load in the greenhouses in
the early season (summer-autumn), various methods can
be applied to improve the climate conditions in the
greenhouses, until a vegetative mass is created which is
able to regulate the greenhouse temperatures by
evaporation (self-cooling by the plants). These methods
include:
1. Evaporative cooling (adiabatic cooling)
The principle of evaporative cooling is based on water
evaporation. In this process, the pressure of water vapor
in the air increases and the air temperature in the
greenhouse drops. In other words, the sensible heat is
transformed into latent heat by capturing the heat in the
water vapor.
There are a number of methods for increasing humidity
Double entry in greenhouse
Double entry in net house
IMPROVING CLIMATE
CONDITIONS IN
SUMMER AND
AUTUMN
in the greenhouse atmosphere, in addition to humidity
resulting from water that evaporates from the plants in the
transpiration process. In recent years, misting and fogging
methods have been developed, joining the wet pad and
fan cooling method. The misting and fogging systems are
differentiated by droplet size. The droplet size has a
significant effect on the process of heat replacement in
the air and the degree that foliage is wetted.
When the droplets are smaller, cooling is more effective
and the leaves are not wetted. In a system with smaller
droplets, the quality of water used for cooling is important,
and this should be taken into account when planning the
cooling system.
a. Cooling by misting:
A misting system for cooling plants is composed of a
system of water lines with low-volume mini-sprinklers (100-
250 droplet size), which have anti-drainage valves. The
system is usually installed at the height of the crop wire
and below the gutter. The mini-sprinklers should be close
enough to each other to wet the entire floor area, without
overlapping. The misting system should operate for 0.5-
1.0 minutes, every 15-20 minutes during the hot and dry
hours. If the system has no control or sensors, operation
frequency and time should be based on the farmer’s
experience. The misting system is switched on and off by
an automatic timer and electric valves. The water wets
the foliage, and cools down the leaves when drying out.
This system is effective on hot, dry days, and is suitable
for use with high quality water. Water with a high
concentration of chlorine and sodium may burn and damage
the plants. This cooling method is designed to reduce leaf
and plant temperatures. The misting system has a marginal
effect only on reducing air temperature.
b. Cooling by pad and fan:
This cooling method, which is common in many
greenhouses, has a wet pad on one wall in the greenhouse,
with fans on the opposite wall. The fans expel the air from
the greenhouse, and as a result of the sub-pressure that
is created in the greenhouse, air is drawn from the wet
pad on the wall opposite the fans. The cooling pad is
composed of a special carton block with narrow air
passages over its entire surface. The carton block is wetted
with a large volume of water using a pump system, which
pumps water in a closed cycle. The air, which is drawn
into the greenhouse, passes through the wet pad and
absorbs the water vapor. This increases the humidity in
the air and lowers the greenhouse temperature.
The disadvantages of this system is that it are very
expensive, the humidity and temperature in the greenhouse
are not uniform, drainage of brackish water is required to
prevent clogging in the wet pad, and the plants are at risk
if there is a power failure, because the system will not
operated especially in hot summer days, when the
greenhouse is closed.The efficiency of the system depends
on the relative humidity outside and the air exchange in
and out of the greenhouse.
15
24. c. Fogging:
This system is based on air vents in the roof, fans on all
sides of the greenhouses and nozzles which are installed
uniformly around the greenhouse. Water droplets (5 – 25
micron) in the form of fog evaporate before reaching the
plant. The air, which enters through the roof vents, carries
the fine water droplets and the water evaporates with the
air flow. Water evaporation in the air cools the air in the
greenhouses and lowers the temperature. The advantage
of this system is uniform cooling of the entire greenhouse,
which enables construction of greenhouses which are
larger than conventional.
In this system, evaporation leaves small grains of salt
which were in the water. These particles may float and
move out of the greenhouse with the air flow, however
some may sink onto the plants and deposit salt on the
foliage. Care should be taken to prevent this by using
water with a good quality or water which has been treated
before use in the fogging system.
2. Temperature reduction by shading -
reducing solar radiation intensity that
penetrates into the greenhouse
a. Whitewashing roofs:
This is the most conventional technical solution for reducing
solar radiation penetrating into the greenhouse, thereby
reducing heat load in the greenhouse. The exterior covering
is sprayed with suitable whitewashing material. It is
recommended to avoid using plaster, which corrodes the
metal and damages the film covering.
16
Diagram of a cooling pad and fan system
Wet pad
Fans
25. When the white coating is new, it reflects some of the
radiation back to the sky, reducing the radiation that
penetrates into the greenhouse, and lowering the
temperature. If the whitewash is sprayed on the roof in
the spring, when the films are dusty, the color achieved
will be brown, and not white. This color usually absorbs
the radiation and generates heat, while producing excess
shading. This combination of lack of radiation and increased
temperature damages the plant, and therefore it is important
to clean the films before applying whitewash.
b. Shade nets:
The radiation intensity and temperature inside the
greenhouse can be reduced by covering the structure with
a knitted or woven black shade net. The net is installed
above the gables, without being too close to the film
covering. The radiation should not be reduced by more
than 20 to 25% of the radiation intensity under a transparent
covering. Shading with this method reduces the
transmission of radiation into the greenhouse, and prevents
a drastic rise in temperature inside the greenhouses.
c. Moveable reflective screens:
A reflective thermal screen, which is spread out during the
hot hours of the day, is another method used to reduce
radiation penetrating into the greenhouse. When the screen
is completely spread out, it reduces the radiation intensity
that penetrates into the greenhouse and lowers the
temperature. The screen is spread out and closed by a
system of twines installed above the crop wire and below
the gutters, and operated by a system of motors that
operate according to thermostats or radiation sensors.
This screen is also used to retain heat and save fuel costs,
when it is spread out at night in the winter. It reduces heat
loss in the greenhouse by blocking escape of infrared
radiation (IR).
Whitewashing roofs to reduce solar radiation intensity
17
Shading with shade nets
Moveable reflective screen
Accumulation of dust on greenhouse and
net house coverings
Covering materials accumulate a great amount of dust,
due to the static electricity on the covering surface, which
attracts dust particles. Dust accumulation reduces light
transmission into the greenhouse or net house, which
damages the yield quantity and quality.
Dust starts to accumulate on the covering material
immediately after it has been spread out. More dust
accumulates in bad weather and when heavy mechanical
equipment operates inside and outside the greenhouses.
Tests show that cleaning the covering films or nets leads
to improved light transmission, resulting in higher yields
and improved quality.
Cleen insect - proof net
Accumulation of dust - low radiation
and limit of ventilation
26. 9
18
The nets should be cleaned to increase light transmission
and air movement, which improves ventilation inside the
greenhouses. The covering films should be cleaned to
improve light transmission into the greenhouses as well.
Cleaning screens to improve ventilation
Insect-proof nets, which are installed on the greenhouse
walls and roof vents, accumulate a lot of dust, which
adheres to the screen threads and blocks the holes through
which the air enters the greenhouse. In order to improve
and increase air passage and ventilation through the
screens, it is important to remove accumulated dust
whenever the screens become clogged.
The screens can be washed by spraying water on them
from the inside of the greenhouse outwards, and from top
to bottom. A high-volume sprayer connected to a suitable
spraying gun, or a hosepipe with a regulated outlet attached
to a tap, can be used for this purpose, since a high-volume
water spray may damage the screen.
Cleaning film covering
In the autumn, when the days become shorter and clouds
begin to gather, dust and lime which is used for shading,
should be removed from the film covering in order to
increase the radiation that penetrates into the greenhouse.
Postponing this treatment damages the yield quality and
quantity. The film covering should be cleaned again during
the winter in order to ensure that they are transparent, to
allow maximum penetration of radiation into the greenhouse.
The film covering can be washed with water and a brush
for mechanical separation of dust from the film. Cleaning
the roofs and coverings increases the photosynthesis
process, resulting in higher yields and improved quality.
Most greenhouse tomato production is dependent upon
hybrid varieties. These seeds are developed by breeding
specialists and sold by commercial companies. The
advantages of hybrid seeds are that they have very high
vigor, good uniformity, high production and quality. Disease
resistances are also bred into these varieties. Growers
should only purchase seeds that have been produced by
reputable companies and are properly packaged in sealed
packages. Labeling should include information about the
variety and proper seed storage.
The production of a seedling, frequently referred to as a
transplant, is an extremely important procedure, as future
plant, growth and fruit production is affected by the character
of the seedling that is produced.
Today, most tomatoes for fresh marketing are grown in
plugs and rooted in a growing medium, which is usually
organic, such as peat, or vermiculite. A good plant is
disease- and pest-free, and has three to five developed
leaves. It has a well-developed root system, with a strong
hold in the growing medium in the tray cell, so that when
SEEDS, SEEDLING
PREPARATION AND
TRANSPLANTING
these seedlings are removed from the tray in the nursery
and brought to the field for transplanting, the growing
medium remains around the roots.
Seedlings that are 3-5 weeks old are considered to be
ideal, while seedlings over 5 weeks old are less desirable.
Trays with 1.25” to 1.5” cells are used to produce quality
tomato seedlings. The seedlings are produced in
commercial nurseries that specialize in seedling production.
The farmer orders seedlings for planting in advance.
Generally, 25 to 50 days are required from sowing until
supply, depending on the season and climatic conditions.
The seedlings should be planted within 24 hours after
removal from the nursery. Early transplanting provides
better conditions for the plants and the future field.
Seedlings received from commercial nurseries are packed
in cartons and kept in a shaded area that is protected from
insects until they are planted.
Tomato plugs are planted in damp soil that has been
irrigated in advance. The seedling’s roots (the plug) should
be straight, and not folded when planted in the ground,
and covered completely by soil. Air pockets are removed
by pressing the soil around the roots with hands or a
trowel. The seedlings should be irrigated lightly within
one to two hours after planting. A quality seedling and
proper planting guarantee establishment of the seedling
in its new environment, and ensure that growing is not
delayed. If seedlings are planted on a hot day, the plugs
should be dipped in water before planting.
Uniform seedlings produced in a commercial nursery
A seedling that is suitable for planting
27. Plant spacing and density –
common tomatoes
Tomato plants in greenhouses are grown in double rows,
which enable optimal growing, radiation and ventilation
conditions, with wide passages between rows for easy
access by workers. A distance of 170-185 cm between
the double-row centers is required, and the span width
should be adapted accordingly. Greenhouses that are
marketed in Israel do not have a uniform span width, and
the span width is adapted to the number of double rows.
The distance between seedlings in the rows is determined
accordingly, and should not be less than 40 cm. A high
yield is achieved with about 20,000-25,000 plants per
hectare. More plants per hectare will not increase the
production. The fruit will be small and puffy with a poor
color, and there will be a higher incidence of disease in
the dense conditions.
Table4.Recommendationsforrowspacing
in greenhouses with varying span width
Estimated
density
per ha.
Plant
spacing
Span
width
Double
rows
per span
50 cm
40 cm
50 cm
45 cm
50 cm
50 cm
50 cm
40 cm
40 cm
45 cm
22,000
25,000
20,000
23,500
21,000
25,000
22,000
23,000
25,000
22,000
5
4
4
4
4
4
3.5
3
3
3
9 m
8 m
8 m
7.5 m
7.5 m
6.4 m
6.4 m
6.4 m
6 m
6 m
Transplanting young plants in double rows
19
In order to increase the radiation that penetrates between
the crop rows and vertical growth, distance between double
rows should be 50-60 cm at the plant base.
This distance can be maintained by fixing the horizontal
crop wires at the same distance or even slightly wider, on
the internal greenhouse frame.
The best position for the double crop rows is one row on
either side of the gutter poles and the other rows are
formed along the span width.
This positioning is convenient for agro-technical activities.
The following diagram illustrates distribution of
crop rows in greenhouses with span widths of
7.5, 8.0 and 9.0 m.
Row spacing in different greenhouses
and span widths
Enough space between the double
rows allows light penetration
9.0 m 9.0 m 9.0 m 9.0 m
7.5 m 7.5 m 7.5 m7.5 m
8 m 8 m 8 m 8 m
Greenhouse with 9.0 m spans
Greenhouse with 8.0 m spans
Greenhouse with 7.5 m spans
28. Tomato plants that are grown in greenhouses are shaped
into one or two main stems by pruning all the sideshoots
(suckers) that develop in the leaf buds on the main stem.
The height of the crop wires in the greenhouse is planned
according to the duration of the harvest season.
1. When the harvest season is limited to 3-4 months,
the crop wires should be 2.2-2.5 m high, so that they
can be reached by the workers. When the plant tops
reach the crop wire, they are bent in one direction
and tied to the central cable with plastic-coated twine.
The plant tops are pruned about one month before
the end of the harvest. Pruning the tops usually
increases the fruits’ diameter in the last 3-4
inflorescences.
With this trellising method, 10-12 inflorescences are
picked from each plant.
Planting a short-season variety is common in various
countries, including the Mediterranean Basin. This
method requires lower investment and fewer work
days, and enables planting of another crop in the
same year.
2. When the harvest season is longer than four months,
a high crop wire system (at least 3.5 m) should be
used. The plant tops are left upright throughout the
harvest season. This method enables lowering of the
central stem by releasing the twine from the hook on
the crop wire. Before lowering the plants, all leaves
on the central stem below the ripened or picked
inflorescences should be removed, so that the stem
from which fruit has been picked lies on the ground.
In this method, the work of twisting plants on twine
or string, pruning of side branches and other activities
are performed when the plant tops reach the height
of the crop wire. Therefore, elevated work carts are
needed to reach the high areas. These carts are
propelled forward either by electric motors or by
mechanical means such as pedal and chain. One
cart for every 0.2 ha is usually sufficient.
The advantage of this method is that inflorescences with
ripe fruit that are ready for harvest are at a convenient
height for picking, especially when harvest wagons are
used. It is recommended to cut the plants’ tops to stop
growth about one month before the end of the planned
harvest. In this trellising method, about 20-25 inflorescences
are picked from each plant.
10 TRAINING
METHODS
20
Plant spacing – cherry tomatoes
Plant spacing of cherry tomato seedlings for single fruit or
cluster harvest are the same as spacing of regular tomatoes.
These seedlings are grown in double rows and the distance
between row centers is 170-185 cm. However, the distance
between the seedlings varies according to the number of
stems growing on each plant. If there is one stem per
plant, the distance between seedlings in the rows is
30-40 cm. This is recommended in light and sandy soils.
When each plant has two stems, there can be a distance
of 60-80 cm between plants. This is conventional in medium
and heavy soils. The growing method of two stems on
one plant is common and conventional when the variety
has especially large fruit and the aim is to reduce the fruit
size, or when grafted seedlings are used.
Two stems from one plant
Pruning the top branches to encourage
development of two identical stems
29. Support for cherry tomato stems
The inflorescences of cherry tomato plants are large and
are not harvested in a short
period and at the same time,
therefore it is recommended to
tie cherry tomato stems to a
support system to keep the fruit
in inflorescence off the ground.
The support system is made of
bent black or galvanized iron
rods, with a 6-8 mm diameter, a
50-60 cm surface width and a 3-
5 cm raised lip on each side to
prevent the stems from sliding
and falling off the support. After
insertion into the ground, the
surface height of the support is
40-50 cm. One support is
installed every 1 meter along the
row. In this way, when the plants
40cmabove
thesurface
20cmin
thesoil
4.0
4.0
60 cm
60cm
21
Diagram of hooks
Various hooks
are lowered and stems with unpicked fruit rest on the
supports at a height of 40 – 50 cm, the fruit does not touch
the ground. With this method the fruit is free of sand and
does not rot as a result of contact with the damp ground.
Training equipment
One plastic or metal hook for each plant is used in high
crop wire training. The hooks are wrapped with 8-10 m of
plastic twine (recommended 900 m/kg). Twine from the
previous crop should not be used, as it may carry viral
disease or tear as a result of wear. New twine is attached
to the hooks for each new crop.
With low crop wires, the same type of twine is used without
hooks and tied to the crop wires which are at a height of
about 2.5 m.
In both methods, the plants are tied to the crop wire by
forming a loose ring around the central stem or by attaching
the twine to the plants with plastic clips. The plants are
wrapped around the twine about once every 7-10 days,
Diagram of supporter
Cherry tomato plants with and without supports
30. depending on the temperature and the plant’s growth rate.
The clips can also be used to attach the stems to the twine
during growth, which eliminates the need for wrapping the
plants around the twine, and significantly reduces breaking
of the plant crowns. When tying the twine to the plants,
the knot or hook on the trellising cable should be moved
sideways by at least 50 cm from the center of the plant,
so that the plant grows at an angle towards the row, with
each row leaning in the opposite direction.
This determines the direction of the plants when lowered,
and the plant leans towards the row and not towards the
work passages.
22
Inserting the twine into the stem
Tying clip and inflorescence support
Pruning suckers or side-shoots
In order to shape the plant into one central stem, all the
side-shoots growing near the leaves should be pruned
throughout the growth period. The side-shoots are pruned
when they are less than 5 cm long and removed from the
base without leaving any remnants on the central stem.
Late pruning leaves a wound which does not dry out
quickly, and is susceptible to penetration of bacterial
diseases and Botrytis. Side-shoots which are not pruned
in time use nutrients and assimilates from the central stem
and damage proper development of the plants. The cut
branches and leaves should be collected into containers
and removed from the greenhouse on the same day.
If a crop with two stems on one plant is planned, as is
conventional with cherry tomatoes and grafted plants, the
first secondary branch under the first inflorescence should
be left, or a plant with two stems should be purchased
from the nursery.
Removing leaves
Old and yellowed leaves are removed after they have
completed their function of photosynthesis. Lower leaves
are removed to increase ventilation close to the ground.
Leaves can be first removed when the plants reach a
height of 1-1.5 m and produce 5-6 inflorescences. At this
stage, 2- 3 lower leaves, which have limited efficiency and
touch the ground, are removed. Leaves are removed
again when the fruit in the first inflorescence is picked.
All the leaves below the inflorescence are removed. When
fruit in another inflorescence is picked, all the leaves below
that inflorescence are removed. Leaves above the
inflorescence with unripe fruit are not removed. In
indeterminate tomato plants, movement of assimilate from
the leaves to the fruit is generally characterized by transition
of assimilates from one leaf below the inflorescence and
another two leaves above that inflorescence. Therefore,
it is important not to remove leaves above or below
inflorescences where the fruit has not yet ripened. It is
recommended to remove leaves on a clear and dry day.
If leaves are removed on rainy or humid days, pesticide
should be sprayed at the end of the process, especially
with copper materials, to prevent bacterial disease.
Sunburn as a result of over exposure to radiation
Plastic clips and cluster supporter
31. 23
Excessive removal
of leaves
Controlled removal
of leaves
The leaves have many tasks apart from supplying nutrients
to the fruit:
In summer, they provide shade for the green fruit and
prevent sunburn or development of fruit with green
shoulders. In winter, the leaves protect the fruit against
chill by preventing heat radiation from the fruit to the
greenhouse atmosphere.
Moderating the temperature change of the fruit reduces
the risk of fruit cracking, especially in autumn. When
removing leaves, they should be broken off at the base,
close to the central stem, without leaving stubs or parts of
the leafstalk on the stem. The leaves are removed by
holding the leafstalk close to the stem in one hand, and
the plant in the other hand. The leaf is moved upwards
and downwards until it is detached from the stem. An
abscission layer (scar) forms where the leaf is removed,
resulting in quick drying of the wound. However, when the
stalk is not cut close to the stem, stubs are left. The wound
does not dry out and it constitutes a source for penetration
of pathogens.
Movement of assimilates
Supporting clusters
In stress conditions, especially where there is lack of
radiation, the cluster stems close to the plant’s central
stem bend. This interferes with the movement of assimilates
to the fruit in the cluster, and in extreme cases it causes
complete abscission of the inflorescence from the stem,
reducing yield and quality. Therefore, when there is an
indication of this, it is recommended to install supports for
the clusters. Increased radiation transmission between
plants in the rows and between the row pairs reduces
damage.
Tomato clusters with
a bent stem
Cherry tomato clusters
Left: A bent stem –
defective color
Right: Straight stem –
normal color
In order to achieve a high quality and quantity yield,
tomatoes should be planted in mild climatic conditions,
which are suitable for flowering and fruit set (see section
that discusses climatic factors and their influence on tomato
plants). Therefore, tomatoes should not be planted when
climatic conditions develop to extreme temperature
combinations. Temperatures that are higher than 32ºC in
the day and 22ºC at night or lower than 18ºC in the day
and 10ºC at night are considered to be detrimental to the
tomato plant and disrupt the flowering and fruit set
processes. The plants’ development rate and properties
are also damaged. In high temperatures, the plants develop
long and sparse internodes. In low temperatures, the
plants develop short and dense internodes.
Tomatoes can be planted in greenhouses in different
seasons, and planting can be planned according to areas,
required harvest period and required duration of yield.
In Israel and countries with a similar climate, tomatoes
can be planted at the end of summer. The crop can be
harvested from the beginning of winter until mid-summer.
11 PLANTING
SEASONS
32. 24
In this way, high yields can be achieved, which justify the
investments and various agro-technical treatments such
as the continuous plant twisting and sucker removal.
Although tomatoes can be planted in other periods, and
in fact, almost year round, the yield periods are short and
the yields level are lower compared to those received when
planting in the optimum period.
There may be various problems in the plants’ fertility in
some planting periods, especially in summer, due to
temperatures that rise to harmful values. Experience
shows that planting in June and July is considered to be
problematic, and the chances of receiving normative yields
in this period are slight.
In very hot regions, where both day and night temperatures
are very high, it is not recommended to plant tomatoes
from the end of spring until the end of summer. The PE
films covering greenhouse roofs and the insect proof nets
on sidewalls also raise temperatures to extreme and harmful
values. In cold regions, it is not recommended to plant
tomatoes in the winter, as plants may be damaged by the
low temperature. However, if the greenhouse is equipped
with a heater which operates in the winter (low temperature),
tomatoes may also be planted in the cold months.
Double-crop production is common in many regions. This
method enables production of a high quality and quantity
yield, without the need to invest in the equipment and labor
used when growing with high crop wires. The disadvantage
of the double-crop method is that production is not
continuous and yields tend to be lower. This method is
suitable where there are many greenhouses and production
and marketing times need to be flexible.
The period from planting until harvest is influenced by the
variety, planting date and climatic conditions in the region.
In the hot season, harvest of early ripening varieties should
start after 60 to 65 days, and harvest of late ripening
varieties should start after 75 to 85 days. However, when
planting in the cold season, early ripening varieties are
harvested after 100 days, while late ripening varieties
require about 120 days until harvest.
Lake of fertility (high temperature)
Collapse of the locules (low temperature)
12
Indeterminate varieties, which are suitable for growing in
greenhouses, are grown on one central stem by
continuously pruning the sideshoots. Researchers are
working to introduce favorable attributes related to fruit
quality and disease-resistance. Varieties are selected
after they have been studied in pilot plots, covering different
seasons and regions. The tests include yield level, fruit
quality, compatibility to local and export market demands
and to different growing conditions. Great success has
been achieved by breeding varieties that are suitable for
growing in greenhouses and which are resistant to soilborne
diseases carried by fungi and nematodes.
Effort has been invested in breeding varieties that are
resistant to viral diseases, especially TYLCV, which is
carried by Bemisia tabaci (whitefly).
If TYLCV-resistant tomato varieties with good yields and
quality are developed, nets with a mesh density less than
50 mesh can be used. This will lead to improved climate
inside the greenhouses by increasing passive ventilation.
TABLETOMATO
VARIETIES
33. 25
Medium
Very Good
Very Good
Medium
Medium/
good
Good
Very Good
Good
Good
Very Good
Medium/
Good
Medium/
Good
Very
Good
Good
Good
Very
Good
Good
Good
Good
Good
Flattened
globe
Flattened
globe
Flattened
globe
Globe
Flattened
globe
Globe
Flattened
globe
Flattened
globe
Flattened
globe
Flattened
globe
Globe
Flattened
globe
Flattened
globe
Flattened
globe
Flattened
globe
Flattened
globe
Flattened
globe
Flattened
globe
Flattened
globe
Flattened
globe
ColorShapeVariety Resistance
Daniela
R-144
Shirley
Anath
FA-189
Nur
259
Dominique
FA-593
Philippos
Abigail
FA-870
Graziella
Cassius
Astona
Gironda
Trofeo
Charlotte
FA-1402
Shannon
Neely
FA-1410
Rosaliya
HT 1141
770-Sandrin
Bonarda
9934-Mali
Firmness Planting
season
V F1 F2 Tm
V F1 F2 Tm
V F1 F2 Tm
V F1 F2 N Tm
V F1 F2 N Tm
V F1 F2 N Tm
V F1 F2 Tm
V F1 F2 Tm
V F1 F2 Tm
V F1 F2 Tm
V F1 F2 Tm
V F1 F2 N Tm
V F1 F2 N
Tm
V F1 F2 Fr N
Tm
V F1 F2 Fr N
Tm
V F1 F2 Fr N
Tm
V F1 F2 Tm
V F1 F2 Fr N
Tm
V F1 F2 Tm
V F1 F2 N
Tm
Good
Good
Good
Good
Good
Good
Good
Good
Good
Good
Good
Good
Very
Good
Good
Very
Good
Good
Good
Good
Good
Good
Autumn/
Spring
Autumn/
Spring
Summer/
Spring
Autumn/
Spring
Autumn/
Spring
Autumn/
Spring
Autumn/
Spring
Spring
Spring
Autumn/
Winter
Autumn/
Spring
Autumn
Autumn/
Spring
Autumn/
Winter
Autumn
Summer/
autumn
Summer/
Spring
Summer
Spring/
Summer
Summer
Vigor
Strong
Medium
Strong
Medium/
Strong
Strong
Medium
Very
Strong
Strong
Strong
Strong
Strong
Strong
Strong
Very
Strong
Very
Strong
Medium
Strong
Strong
Medium
Strong
Table 5. Common single-harvest tomato varieties and different growing seasons
The following tables present information about varieties that are suitable for growing in greenhouses and
nethouses. The varieties in the table are recommended for planting in Israel, and may also be suitable
for planting in Mediterranean countries, North Africa, Latin America and other countries with similar climatic
conditions.
34. 26
ColorShapeVariety Resistance Firmness Planting
season
Vigor
Good
Good
Good
Good
Good
Very Good
Medium/good
Medium/good
Medium/good
Good
Good
Good
Flattened
globe
Flattened
globe
Flattened
globe
Flattened
globe
Flattened
globe
Flattened
globe
Flattened
globe
Flattened
globe
Globe
Flattened
globe
Large
globe
Flattened
globe
Meitar
FA-1907
Michaella
FA-1903
Melissa
FA-1415
Nemoneta
Natalya
Bonaque
Colette
HA-832
HA-3209
DRW-6478
Minhir
Brillante
FA-179
Nerissa
FA-1420
V F1 F2 N
Tm
V F1 F2 Fr N
Tm
V F1 F2 Fr N
Tm
V F1 F2 N
Tm
V F1 F2 N
Tm
V F1 F2 N
Tm
V F1 F2 Tm
V F1 F2 N
Tm Ty
V F1 F2 N
Tm Ty
V F1 F2 N
Tm
V F1 F2 Tm
V F1 F2 Fr N
Tm
Good
Good
Good
Good
Good
Good
Good
Good
Good
Good
Medium
Good
Summer/
autumn
Autumn
Spring
Autumn
Autumn
Autumn/
Spring
Autumn/
Spring
Autumn
Autumn
Autumn/
Spring
Autumn/
Spring
Spring/
Summer
Strong
Medium/
Strong
Strong
Strong
Strong
Strong
Strong
Strong
Strong
Medium/
Strong
Medium
Medium
Table 5. Continuation
35. 27
For example, Spain is considered to be a large vegetable
producer, particularly of tomatoes.
Tomatoes are produced year round for local and export
markets. Production areas are distributed in different
regions, including the mainland and Canary Islands. Spanish
tomato production is characterized by its wide range of
colors, sizes and shapes.
Main varieties for different market segments in Spain:
Cluster harvest: Pitenza, Ikram, Durinta.
Single red fruit: Daniela, Jamile, Boludo, Kampala,
Doroty, Eldiez, Bombay, Brillante
Breaking color (Pinton): Isabella, Carolina, Tyrade,
Caramba, Rafter, Raferty, Rambo, Salvador, Lido, Zinac
Specialty: Patrona, Realeza, Evaluna, Cencara, Reva,
Miriade
Cherry tomatoes for single and cluster harvest:
Alina, Conchita, Josefina, Karmina, Katalina, Natacha,
Lupita, Salome, Shiren, Zarina.
Resistance Code:
Key to characterizing and identifying tomato varieties’
resistance and tolerance to pests:
F1: Fusarium oxysporum f. sp. Lycopersici - race 1
F2: Fusarium oxysporum f. sp. Lycopersici race 2
V: Verticillium dahliae
Fr, Cr: Fusarium oxysporum f.sp. radicis lycopersici
crown and root rot
P, K: Pyrenochaeta lycopersici - Corky root
N: Root-knot nematode - Meloidogyne sp.
Tm: Tobacco mosaic virus
Ty: Tomato yellow leaf curl virus
C: Leaf mold - Cladosporium fulvum-Fulvia Fulva
Wi: Silver leaf
Sw: Tomato spotted wilt virus (TSWV)
Pto: Bacterial speck
Lt: Powdery mildew
Many local and international breeding teams are involved
in the intensive activities surrounding breeding of tomato
varieties. It can be assumed that the list of varieties may
change according to progress of the breeding process.
New varieties are usually selected because they have
better yield, quality and resistances than the conventional
varieties that are used.
Cherry tomatoes are one of the tomato products that are
grown in Israel and targeted for the local market as well
as for US and European markets. Cherry tomato production
is also common in many other countries. Production has
expanded in recent years, because of longer shelf life and
better taste.
Single cherry tomato Cherry tomato clusters
Cherry tomatoes in full bloom
These tomatoes are characterized by round fruit, high-
quality taste and long shelf-life. Cherry tomatoes are
produced throughout the year, mostly in greenhouses and
net-houses, with a small percentage produced in open
fields.
The optimal diameter of cherry tomatoes is in the range
of 18 to 30 mm, however fruit with a 30 to 35 mm diameter
is also marketed, although on a smaller scope and to
special markets.
The cherry tomato is sorted into groups according to
diameter and packed in different packages, according to
the buyers’ requirements. Cherry tomatoes can be grown
for cluster harvest. These are special varieties which have
clusters with symmetrical shapes, uniform fruit size and
uniform ripening.
In cluster cherry tomatoes the fruits are connected
symmetrically, in a fishbone shape, to both sides of the
inflorescence and create a cluster with 8 to 12 fruits.
13 CHERRY
TOMATO
VARIETIES
36. 28
Cherry tomato clusters before harvest Defective fertility in cherry tomatoes - high temperature
Table 6. Common cherry tomato varieties
for greenhouse production
Cluster harvest
Single harvest
Variety Resistance
-
VF1 Tm
F N Tm
F N Tm
V F1 Tm Pto
V F1 F2 Tm
F1 N Tm C5
V F1 F2 Fr N Tm Pto
V F1 F2 Fr N Tm Pto
Josefina R-139
Bambino
Zarina
Natacha
Dominion DRC-316
Damita FA-1392
Katalina
Alina
Karmina
V F
VF Tm
Naomi R-124
Camellia R-819
V F1 F2 Fr Tm C5 Wi
F1 F2 N Tm
F1 N Tm C5
F1 Tm
V F1 Tm Pto
V F1 F2 N Tm Ty C5
Conchita
Shiren Fa-1335
Rubino Top
Victories
Diamante
TyTy (C1002-20)
Planting periods for cherry tomatoes
Planting periods for cherry tomatoes are directly influenced
by supply and marketing agreements which are determined
between the grower and exporter and of course by the
climatic conditions in the region.
Similar to regular tomatoes, cherry tomatoes are also
sensitive to extreme temperatures, both high and low.
The planting season should be planned so that most of
the growing, flowering and fruit set take place when there
are no continuous extreme temperatures. Under extreme
climatic conditions, there may be disruptions in the plants’
fertility, inflorescence shape and flower size, and the
flowers’ fertility may be defective.
37. Marketing of vine ripened cluster tomatoes has recently
expanded in many countries. This innovative product is
marketed through a marketing channel which supplies
tomatoes with a fresh appearance: fruit on a cluster with
the green cluster stem and calyx being hallmark signs of
recently harvested fruit and thus freshness. Varieties that
are suitable for cluster harvesting must have a stem and
calyx that remain green and fresh for a long time and
prevent the fruit from dropping off the cluster during
transportation.
All tomato varieties have fruit which grow on a truss/cluster;
14
GROWING
TOMATOESFOR
CLUSTER
HARVESTING
29
Clusters: green and ready for harvest
Cluster tomatoes
however varieties that are suitable for cluster harvest have
a central axis with the fruit attached symmetrically in a
fishbone shape. Tomatoes that are harvested in clusters
can be characterized and classified into groups by the fruit
size and diameter of the fruit on the cluster. Each group
has varieties which meet different marketing requirements.
Groups according to fruit diameter:
1. Regular tomatoes: fruit with a 55 to 75 mm diameter,
4 to 6 fruits per cluster.
2. Cocktail/baby tomatoes: fruit with a 35 to 55 mm
diameter, 5 to 8 fruits per cluster.
3. Cherry tomatoes: fruits with a 20 to 35 mm diameter,
8 to 12 fruits per cluster.
The chance of receiving a good cluster/truss, which is
uniform in size, shape, color and firmness, depends on
varieties which are able to flower and ripen fully in a
relatively short time between opening of the first and last
flowers in the inflorescence. Five to seven days is
conventional for full flowering. This enables production
of a quality cluster with uniform ripening.
Production of clusters with high quality and uniform fruit
requires suitable and stable climatic conditions through-
out the growing period. Changes in climatic conditions,
especially in temperature, have a decisive influence on
the character and shape of the clusters that develop.
Cluster shaping
Uniformity of the fruit size in the inflorescence is achieved
by agro-technical treatments applied throughout the growing
period. These treatments include removal of the first
flower, when this flower is too large or clearly deformed.
This is conventional in varieties that are targeted for cluster
harvesting and which have particularly large fruit. Pruning
the last flowers in the inflorescence, after fruit set of a
minimal number of fruit, is required according to the groups,
which were defined by fruit diameter. This is conventional
in varieties with a large number of flowers in the
inflorescence, especially cherry varieties.
Planting dates for cluster harvesting
Varieties which are designated for cluster harvest should
be planted when the climatic conditions are good for fruit
set from the first inflorescence, so that fruit set is not
damaged by high summer temperatures. Unsatisfactory
fruit set and ripening results in non-uniform clusters which
are not suitable for marketing as cluster tomatoes. It is
recommended to strive for the optimal planting time in
different areas, in order to achieve perfect ripening
beginning with the first cluster. In winter, it is recommended
to operate a heating system in greenhouses for both
agronomical and economical aspects:
Production of a normal inflorescence
Uniform flowering and fruit-set rate in the inflorescence
Uniform ripening of the fruit in the cluster
Increase of yield by accelerating the fruit’s ripening
rate
Increase in the number of clusters that are picked
38. 30
Following the market’s saturation with regular tomatoes,
new tomato products are being developed, which are
designated for local and export markets. Development is
conducted in different, parallel and similar paths, from the
aspect of the goals and objectives. Developing new
products involves professional agro-technical investment,
as well as development of special markets, which means
Cocktail tomato cluster, 35-50 mm
Plum tomatoes
Midi-plum tomatoes
Mini-plum tomatoes
Table 7. Tomato varieties suitable for
harvesting in clusters
Variety CommentsResistance
Symmetrical cluster,
medium-sized fruit, good
firmness, medium color
V F1 F2 N TmPrincess- AB 2536
Symmetrical cluster,
medium-sized fruit, good
firmness and color.
Requires special variety
treatments - sensitive to
microelement deficit.
V F1 F2 TmDorinta
Symmetrical cluster,
medium/large-sized fruit,
good firmness, medium
color, suitable for growing
in brackish conditions.
V F1 F2 N TmDominique
FA-593
Symmetrical cluster,
medium/large-sized fruit,
good firmness, medium
color, suitable for growing
in brackish conditions
V F1 F2 TmDaniella-R 144
Symmetrical cluster, 5-6
fruits in cluster, good
firmness and color,
medium-sized
F1 F2 N TmIkram
Symmetrical cluster,
globe, 5-7 fruits in cluster,
good color, medium-sized
V F1 F2 Fr N
Tm C5
Risoka
Symmetrical cluster, 6-8
fruits in cluster, medium
color and medium-sized
V F1 F2 TmPetenza
Symmetrical cluster, 5-7
fruits in cluster medium-sized
V F1 F2 TmFH-1476
Symmetrical cluster,
medium sized fruit, 6-8
fruits in cluster medium-sized
V F1 F2 TmFA-62203
Symmetrical cluster,
globe,good color, relatively
small-medium size of fruits
V F1 TmR-62202
15 NEW TOMATO
PRODUCTS
changes in consumer behavior and the acceptance of the
new products as something new and innovative and not
simply an alternative to tomatoes. The production and
marketing of the new products demands perseverance
and professionalism because of the time it takes for the
market to absorb new products.
Main properties of the new products:
Unconventional shape and color
Consumed in smaller amounts
High value and returns
39. 31
Colorful cluster tomatoes
Development of the new product requires
the following:
Definition and characterization of the product
Agro-technical development
Market development
Penetration of product
New products include:
Deep globe tomatoes: with different colors and sizes,
such as plum, midi-plum and mini-plum
Colorful tomatoes: orange or yellow, as well as the
conventional and common red. Can be grown for
single or cluster harvest.
Flavor tomatoes: with especially high TSS and sugar
level. Different sizes, deep globe or globe. Can be
grown for single or cluster harvest.
Beef tomatoes: large tomatoes, which are flat and have
a diameter of over 82 mm. When the fruit is cut in half,
its fleshiness and large number of locules are apparent.
Tomatoes with special nutritional value or with high
levels of lycopene or β carotene, which are known to
have special medical value.
Colorful deep globe tomatoes
Orange cherry tomatoes
Single colorful tomatoes
Yellow cherry tomatoes
Flat beef tomatoes
Aranka tomatoes
40. Cencara-deep globe fruit
32
Italdor-very deep globe fruit
Mix of tomato products
Mini-plum packed for export
Regular tomatoes
Yellow and red cherry tomatoes
Cherry tomato Cluster
Marinda (Marmande type)
41. Table 8. Varieties of special tomatoes (Different Products)
Single/cluster
Variety Features
Goldita DRC-89 Yellow, globe cherry
FA-1339 Yellow, globe cherry
Drk-941 deep globe cocktail, deep red with green stripes
Orangeno
DRC-1039
Orange, Mini plumDrk-927
Orange, globe cocktail
Melody AB-8061 Mini-plum deep globe cherry
DRC-353 Mini-plum deep globe cherry
DRC-377 Mini-plum
HA-4801 Mini-plum
HA-1331 Mini-plum
FA-1328 Mini-plum
Revello Mini-plum - mini S. Marzano
FA-654 Deep globe midi-plum
Columbus-RZ Deep globe midi-plum
Flavorino
DRC-186
Deep globe midi-plum
NR-8387 Midi-plum
98-AB-550 Deep globe plum
FA-1413 Deep globe plum
Romana Deep globe plum
FA-62201 Deep globe plum
FA-1463 Deep globe plum
Ovata-RZ Deep globe plum
Pisa Deep globe plum
Cencara Deep globe plum
Oscar
Italdor Long plum, S. Marzano type
Aranka Medium cocktail, globe
Rosalinde
FA-631
Large cocktail, globe
FA-643 Large cocktail, flattened globe
BabyMaya
FA-646
Medium cocktail, globe
FA-612 Globe cocktail
Single
Harvest
Single
Single
Single
Cluster
Single
Single
Single
Cluster
Single
Single/cluster
Single/cluster
Single
Single
Single/cluster
Single/cluster
Single
Single
Single
Single
Single
Single/cluster
Single/cluster
Single
Single
Single
Cluster
Cluster
Cluster
Cluster
Single
Resistance
Tm C5
V F1 Tm
V N Tm
V F1 F2 Tm
V F1 F2 Tm C5
V F1 N Tm
V F1 F2 N Tm
V F1 F2 Tm C5
V F1 F2 Tm Pto
V F1 N Tm
F Tm
VF1 FrNTmPto
VF1 F2 Tm
VF1 F2 FrTmC5
VF1 F2 NTm
VF1 F2 NTm
VF1 F2 NTm
VF1 F2 Tm
VF1 F2 NTmLt
VF1 N Tm
VF1 Tm
VF1 F2 NTm
VF1 F2 NTm
VF1NTm C3
VF1F2FrNTmC5
VF1 NTm
V F1 F2 Tm C5 Wi
VF1 F2Tm
VF1 F2Tm
VF1 F2FrNTm
VF1 F2 Tm
DRK903 VF1 F2 Tm Orange, medium size
Marinda VF1 Tm Marmande type, flattened rib Single/cluster
33
Long plum, S. Marzano type
42. 34
16
PARTIALRESISTANCE
TO ROOT KNOT
NEMATODES
There are many types of nematodes that cause damage
to tomatoes. The most common type is the root knot
nematode (Meloidogyne spp.), which causes a disease
that is recognized by swollen nodules on the plant roots.
Nematode infestation severely damages the plants, causing
lack of absorption of water and nutrients. The plants become
weak and the yield is low. In severe infestation, the knots
on the roots multiply, until absorption of water and nutrients
stops completely and the plants wilt and die.
There are four common types of Meloidogyne spp.
nematodes: M. Javanica, M. Incognita, M. Arenaria and
M. Hapla.
Today, tomato varieties which are resistant to root knot
nematodes contain the MI gene. This gene provides
resistance to M. Javanica, M. Incognita and M. Arenaria
species, but not to M. Hapla species. The resistance
provided by the MI gene breaks down in soil temperatures
above 27-28ºC, causing heavy damage to the plants,
sometimes to the extent of collapse and wilting. If a farmer
plans to plant a nematode-resistant variety in greenhouses
during the hot season, it is recommended to apply all
possible means to ensure that the soil (or growing medium)
temperature does not exceed 27-28ºC. If the soil is infested
with nematodes, it is recommended to sterilize before
planting, applying one of the methods that reduces the
nematode population.
Resistant plants develop small knots on the roots, even
when the soil temperature is not high. This may occur in
resistant plants that are heterozygous around the MI gene
(contain only one copy of the gene in each cell). In this
case, the resistance does not break down and the plants
continue to develop normally, without any damage to yield
level, despite the appearance of small knots on the roots.
Diagram of nematode symptoms in various plants
Right: resistant variety; left: sensitive variety
Propagation by grafting is a well-known and conventional
method used in orchard and rose crops. Over the last
several years, grafting has been introduced in vegetables.
In this method, a scion of a variety or cultivar, which is
capable of producing a quality commercial yield, is grafted
onto rootstock which is capable of growing in harsh soil
conditions. These adverse conditions include soil infested
with nematodes and soilborne diseases, lack of aeration,
high salinity and other problems. In this way, a susceptible
variety/cultivar can be grown in soil which was previously
unsuitable, achieving commercial yields.
Propagation by grafting has become conventional in
vegetables, especially tomatoes, and it serves as a means
to control soil problems, such as root diseases. In some
cases, it was found that the grafted plant develops greater
vegetative growth as compared to a regular plant. The
possibility of growing two stems on each grafted plant is
being examined. This will reduce plant density and of
course save the grower money.
Tomato rootstock varieties have a wide range of resistance
to soilborne diseases. The grafting method can therefore
reduce the need to sanitize soil with every planting.
Moreover, the use of methyl bromide can be dramatically
reduced and even eliminated as grafted varieties, together
with a range of new chemicals to control soil diseases,
are used.
17 ROOTSTOCK
AND GRAFTING
Grafted plants
