Grafting is a method employed to improve crop production. Grafting of vegetable seedlings is a unique horticultural technology practiced for many years in East Asia to overcome issues associated with intensive cultivation using limited arable land.The first grafted vegetable seedlings used were for Watermelon (Citrullus lanatus L.) plants grafted onto Lagenaria siceraria L. rootstock to overcome Fusarium wilt. Since then, the use of grafted solanaceous and cucurbitaceous seedlings has spread, with the practice mainly used in Asia, Europe, and North America. The expansion of grafting is likely due to its ability to provide tolerance to biotic stress, such as soilborne pathogens, and to abiotic stresses, such as cold, salinity, drought, and heavy metal toxicity, due to the resistance found in the rootstock. Many aspects related to rootstock/scion interactions are poorly understood, which can cause loss of fruit quality, reduced production, shorter postharvest time, and, most commonly, incompatibility between rootstock and scion. The rootstock and scion cultivars must be chosen with care to avoid loss.

1. ANNAMALAI UNIVERSITY

2. Grafting is the combination of two identical
formulation plants which grow as one plants.
Vegetable grafting is a modern technique used to
control soil pathogens in which vegetative growth
of weak root combination is grafted on selected
rootstocks of disease and pest resistance and
adaptive to environmental changes. Rootstock
Scion

3. Cultivated area using grafted seedlings, and the estimated number of grafted
vegetable seedlings in Korea and Japan. About 337 million grafted seedlings are
planted annually in Korea and »651 million in Japan (field and greenhouses). More
than 95% of the watermelons in both countries are grafted. The majority of
greenhouse cucumbers are grafted, but only »10% to 30% of cucumbers for growth in
the field are grafted. Most of the Oriental melons are grafted to squash (Cucurbita
spp.) rootstock (Ito, 1992; Jang et al., 1992)

4.  The raising of grafted plants of vegetables was first initiated in Japan and
Korea during late 1920’s with watermelon onto gourd rootstock.
 In the 1950’s, eggplant was grafted onto scarlet egg plant (Solanum
integrifolium ). At present, more than 95% of watermelon and oriental melon in
Japan, Korea and Taiwan are grafted on squash and gourd rootstock before
transplanting. In Greece, cucurbit grafting is very popular.

5. Current status
FAO statistics 2008

6. The main objectives of vegetable grafting is to eliminate soil borne pests that
infect vegetables and problems of salinity and soil acidity. Other objectives of
grafting are to increase productivity, to increase the grafted plant tolerance to
different temperature.

7. Vegetables objectives
Cucumber Tolerance to fusarium wilt, Phytophthora melonis, cold
hardiness, favourable sex ratio, bloomless fruits.
Egg plant Tolerance to bacterial wilt, verticillium wilt, fusarium wilt,
low temperature, nematodes, induced vigour and enhanced
yield.
Tomato Tolerance to corky root, better colour and greater lycopene
content, tolerance to nematode.
Melon Tolerance to fusarium wilt, physiological disorders,
Phytophthora diseases, cold hardiness, enhanced growth.
Watermelon Tolerance to fusarium wilt, Physiological disorders, cold
hardiness and drought tolerance.
Bittergourd Tolerance to fusarium wilt.
Objectives of grafting
Pandey and Rai, 2003

8. Cucurbitaceae: Muskmelon, Watermelon, Cucumber, Squash
Solanaceae: Brinjal, Pepper, Tomato

9. Intergeneric grafting is common in fruited vegetables, e.g. watermelon are
normally grafted on bottlegourd ( lagenaria siceraria ) or to interspecific hybrids.
In Japan, the muskmelon is generally grafted onto hybrid melon cv. Base and the wax
gourd ( Benincasa hispida ) cv. ‘partner’.

10.  Cucumbers are generally grafted onto figleaf gourd ( cucurbita ficifolia ) or inter-
specific hybrid ( Cucurbita maxima x C.moschata ).
 Rootstocks such as scarlet eggplant Solanum integrifolium , solanum torvum and
solanum nigrum are exploited for grafting of egg plant.
 Sponge gourd ( Luffa aegyptiaca ) is used as a resistant ( Fusarium wilt ) for
bittergourd.
 Tomato is usually grafted on egg plant, solanum torvum, intergeneric rootstocks and
KNVF hybrids.
Cont..

11. Scion Rootstocks
Cucumber Cucurbita moschata, Cucurbita ficifolia, Cucurbita maxima
Melons Cucurbita Spp, Cucumis melo, Cucurbita moschata x Cucurbita
maxima, Benincasa hispida
Watermelon Citrulus lanatus, Cucurbita maxima, Cucurbita moschata,
Cucurbita moschata x Cucurbita maxima, Lagenaria siceraria
Bittergourd Cucurbita moschata, Lagenaria siceraria, Luffa aegyptiaca
Tomato Lycopersicon pimpinellifolium, L.esculentum, Solanum nigrum
Egg plant Solanum torvum, Solanum integrifolium, Solanum melongena,
Solanum nigrum
Different rootstocks for grafting of vegetables
Pandey and Pandita, 2002

12. CROP ROOTSTOCK SPECIES DESIRABLE TRAITS
Tomato Lycopersicon pimpinellifolium(L.) Mill Nematode resistance
Lycopersicon hirsutum Nematode resistance
Solanum integrifolium Tomato sugar content increase
Solanum sisymbrifolium Tomato disease resistance
Solanum torvum Disease resistance, Nematode
tolerance
Solanum nigrum L. Fruit size and quality control
Brinjal Solanum torvum Disease resistance, nematode
tolerance
Solanum integrifolium Low temperature tolerance
DESIRABLE CHARACTERS OF ROOTSTOCKS

13. Water melon Lagenaria siceraria L. Vigorous root system, fusarium
tolerance, low temperature tolerance
Cucurbita moschata Vigorous root system, fusarium
tolerance, low temperature tolerance
Interspecific hybrid squash-
Cucurbita maxima x Cucurbita
moschata Duch.
Vigorous root system, fusarium
tolerance, low and high temperature
tolerance
Benincasa hispida Good disease resistance
Cucurbita pepo L. Vigorous root system, fusarium
tolerance, low temperature tolerance
Cucumis metuliferus E. Mey.ex Naud Fusarium tolerance, Nematode
tolerance
Cucumber Cucurbita ficifolia Bouche. Low temperature tolerance, good
disease resistance
Cucurita moschata Duch. Fusarium tolerance, fruit quality
modification
Cucurbita maxima Duch. X
C.moschata Duch.
Fusarium tolerance, Low
temperature tolerance
Cucumis metuliferus E. Mey.ex
Naud.
Fusarium tolerance. Nematode
tolerance
CONT…

14. In grafting, it is important to increase the chances for vascular bundles of the scion
and rootstocks to come into contact by maximizing the area of cut surface that are spliced
together. After grafting, a temperature of 30oC and 95% RH is maintained for fast healing
and better survival of graftage. Gradually, the relative humidity is then lowered and the light
intensity is increased.
The development of graft union is depended upon the formation of an isolation
layer and a parenchymatous callus to the occurrence of symplastic contact between the cells,
notably the sieve elements of the rootstock and scion.

15. Various methods of grafting are:
Cleft grafting
Whip and tongue grafting
Splice grafting
Flat grafting
Saddle grafting
Bud grafting
Hole insertion grafting
Tongue approach grafting.

16.  This method of grafting is practiced in tomato.
For successful union, seeds of rootstock are sown 5-7 days
earlier than those scion.
 The stem of scion ( at four leaf stage ) and the
rootstock ( at four to five leaf stage ) are cut at right angles,
each with 2-3 leaves keeping on the stem.
 The stem scion is cut in a wedge and the tapered
end is fitted into a cleft cut in the end of the rootstock. The
graft is held firm with a plastic clip.

18.  This method of grafting is very popular among Japanese seedling procedure to graft
small plants grown in plug tray 2-3 times faster than the convenient method.
 The optimum growth stage for grafting varies according to the kind of plug used.
 plants in small cells are grafted at earlier growth stage which require small size
tubes.

19.  First, the rootstock is given a slanting cut and the scion is also cut in the same
way.
 elastic tubes with side slit are put on the cut end of the root stock.

20.  The cut ends of the
scions are inserted into the tube,
splicing the cut surfaces of the
scions and rootstocks together.
 Tube grafting is practiced
in brinjal onto the rootstock of
Solanum torvum.

21.  This method is common in melons and other cucurbits.
 In such case, seeds are sown 10-13 days before grafting for
cucurbits and 7-10 days before grafting for pumpkin to ensure
uniformity in diameter.

22.  The hypocotyls of the scion and rootstock are cut in such a way that
they tongue into each other and the graft in secured with a plastic clip.

23. The hypocotyl of the scion is left for 3-4
days and then The hypocotyls is cut off
with sharp blade 3 or 4 days after crushing.

24.  In this method, the first leaf and lateral buds are removed when a slanting cut is given to
a cotyledon of the rootstock.

25. Recently, grafting robots for plugs have been developed by combining
the adhesive and grafting plates which facilitates simultaneous grafting for eight
plugs of tomato, eggplant or pepper, nowadays, a fully automatic grafting system
has been designed for cucurbitaceous vegetables in which quality seedling plants
are produced by using fuzzy logic and neural network. In addition, a heating
chamber with controlled atmospheric conditions has been designed to enhance the
survival of the graftage.

28. Yoshioka, 2001

29. The main objective of grafting is to reduce soil borne diseases like Fusarium wilt in
cucurbitaceae( Cucumber, melon etc.) and bacteria wilt in solanaceae (Tomato, pepper). The
use of resistant rootstocks in combination with integrated pest management reduces the
requiring soil fumigation with methyl bromide in many crops and it is effective in organic
farming of vegetables.

30. Grafting fruiting vegetables to manage soilborne pathogens, foliar
pathogens,
Frank J. Louwsa,∗, Cary L. Rivarda,b, Chieri Kubotac

31. BACTERIAL WILT

32. BLIGHT

33. Sicyos angulatus and pumpkin have been found to be promising
rootstocks to avoid nematode infestation in cucumber. In tomato, nematex
rootstock gives complete resistance against nematode infection. Other rootstocks
used against nematode in tomato are KNVF and solanum nigrum.

34. Capsicum annuum rootstocks with N gene resistance offered effective
control of Mi when grafted to a popular commercial bell pepper (Kokalis-Burelle et
al., 2009).
Accessions C. annuum, C. frutescens, C. chinense, C. chacoense and C.
baccatum were moderately to highly resistant to Mj but susceptible to M (race 2)
(Oka et al., 2004). However, a C. annuum rootstock selection (AR-96023) and C.
frutescens accession had moderate and high resistance to Mi and Mj, respectively, and
the AR-96023 rootstock
Grafting fruiting vegetables to manage soilborne pathogens, foliar
pathogens, arthropods and weeds
Frank J. Louwsa,∗, Cary L. Rivarda,b, Chieri Kubotac

35. NEMATODE
Rivard et al. (2010) showed that under heavy natural Mi inoculum pressure and in hot
soils, non-grafted tomatoes were severely galled whereas ‘Maxifort’ and ‘Beaufort’ had a
low incidence of galling and ‘Big Power’ had trace amounts of galling in 2 consecutive
years.

36. Some cucurbitaceous crops like melons and cucumber produce phenolic acid from
root tissue and root exudates known as autotoxins and these chemicals affect ion uptake,
membrane permeability, photosynthesis and phytohormone balance. Such type of
autotoxicity in cucurbits can be reduced by grafting on cucurbita ficifolia.

37. Grafting is effective to initiate the flowering and fruitset at low temperature
which saves the energy of polyhouse to maintain day/night temperature regime. In
cucumber, early yield is recorded by grafting on cucurbita ficifolia through the reduction of
temperature regime of polyhouse from 230 C/200C and grafted plants survive at very low
temperature at 100C.

38. Tomato (cv. Big Red) grafted onto cv. Heman [S. lycopersicum L.×L.
hirsutum (Vahl) Dunal] and Primavera (S. lycopersicum L.) produced more
fruits than the control in the greenhouse, however, under low-temperature
conditions in the field the positive effect almost disappeared (Khah et al.,
2006).
On the other hand Zijlstra and den Nijs (1987) demonstrated under
low day- and night-temperature conditions of 18/7 ◦C a high variability in the
contribution of 29 tomato rootstocks to earliness of flowering, fresh weight of
trusses and shoots, and fruit production.
Grafting as a tool to improve tolerance of vegetables to abiotic stresses:Thermal
stress, water stress and organic pollutants
Dietmar Schwarza,∗, Youssef Rouphael b, Giuseppe Collac, Jan Henk Venemad

39. For tomato, rootstocks of the high-altitude accession LA 1777 of S.
habrochaites (synonym L. hirsutum Dunal, Venema et al., 2008), ‘KNVF’ (the
interspecific hybrid of S. lycopersicum×S. habrochaites, Okimura et al., 1986)
and chill-tolerant lines from backcrossed progeny of S. habrochaites LA1778×S.
lycopersicum cv. T5 (Bloomet et al., 2004) were able to alleviate low root-
temperature stress for different scions.
For watermelon, grafting onto Shin-tosa-type (an interspecific squash
hybrid, Cucurbita maxima×C. moschata) rootstocks is used to advance the planting
date during cool periods (Davis et al., 2008).
CONT…

40. Intergeneric grafting increases flood tolerance in cucurbits eg., flood prone bitter melon
onto flood tolerant Luffa rootstock.

41. Grafting as a tool to improve tolerance of vegetables to abiotic stresses:
Thermal stress, water stress and organic pollutants
Dietmar Schwarza,∗, Youssef Rouphael b, Giuseppe Collac , Jan Henk Venemad
Grafting improved flooding tolerance of bittermelon (Momordia charanthia
L. cv.) when grafted onto luffa (Luffa cylindria Roem cv. Cylinder) (Liao and Lin,
1996).
The reduction of the chlorophyll content in cucumber leaves induced by
water logging was enhanced by grafting onto squash rootstocks (Kato et al., 2001).

42. In cucumber more number of commercially acceptable and shiny fruits are
obtained by grafting on squash hybrid kky. Enhanced sugar content in galia and haon melon
has been reported by grafting of rootstock of either of the melon cultivar ‘suiker’ or ‘841’. In
tomato grafted plants produce increased number of marketable fruits and decreased number
of malformed, under developed and gray mold infected fruits and had fruits with better
colour and highest lycopene content.

43. Fruit size resulted in higher yield since grafted plants are resistant to soilborne
disease, has strong root systems, and increased photosynthesis (Xu et al., 2005a; Qi et al.,
2006).
Salamet et al., (2002) demonstrated a 3.5 times higher yield in grafted
watermelon [Citrullus lanatus (Thunb.) Matsum and Nakai] due to larger fruit size, and
more fruit per plant.
PHYSICAL PARAMETERS
Impact of grafting on product quality of fruit vegetables
Youssef Rouphael et al.,

44. Yetisir and Sari (2003), and Yetisir et al. (2007) reported that
watermelon grafted on interspecific squash hybrid (C. maxima Duchesne×C.
moschata Duchesne) had increased fruit size by 52%.
Two squash interspecific hybrid rootstocks (‘Shintoza’ and
‘Tetsukabuto’) increased both watermelon yield and fruit size by an average
of 90% and 26%, respectively compared to ungrafted watermelon plants
(Miguel et al., 2004).
Colla et al. (2006a) reported that (redness/yellowness)
measured on the surface of the external pulp of melon were significantly
higher in grafted plants compared to ungrafted plants grown under
greenhouse conditions
CONT…

45. Watermelon fruits obtained fromplants grafted onto Lagenaria rootstocks
(Yetisir et al., 2003), and C. maxima×C. moschata (‘RS841’ and ‘Shintoza Camelforce’)
were firmer by 24% and 27%, respectively than the fruits from the ungrafted plants
(Huitrón-Ramírez et al., 2009)
Another study also reports a substantial increase in melon firmness from
grafted ‘Proteo’ plants onto ‘P360’ (C. maxima Duchesne×C. moschata Duchesne) by
19–32% (Colla et al., 2006a).
Similarly in cucumber, flesh firmness was higher with fruits from plants
grafted onto ‘Andong’ (Sicyos angulatus L.) rootstock as compared to those grown on
their own roots.
FIRMNESS

46. Proietti et al. (2008) demonstrated that mini-watermelon grafted onto the
commercial hybrid rootstock ‘PS 1313’ (C. maximaDuchesne×C.moschataDuchesne)
exhibited higher TSS.
Matsuzoe et al. (1996) evaluated fruit quality of ‘Momotaro’ tomatoes as
influenced by three different rootstocks of Solanum species, Solanum sisymbriifolium,
Solanum torvum and Solanum toxicarium. They concluded that the fruit quality of the
tomato plants grafted on other Solanum species was not different from that of tomato
on its own roots.
CONT…

47. Cucumber grafted onto cucurbita ficifolia produces faster and 200 per cent early
yield. This rootstock is also exploited for late crops. In summer cucumber, frequency of
harvesting fruits is increased y grafting on Hokushin or Aodai rootstocks. Highest early
yield of melon cv ‘ galia’ and ‘halon’ is obtained when grafted on rootstocks either ‘suiker’ or
‘841’.

48. Grafting effects growth and minerals content of the plant tissue especially the role
of roots and shoots in regulation of Fe efficiency in grafted cucumber. In cucumber grafting
on cucurbita ficifolia reduces the Mg deficiency. Cucumber cultivars producing fruits with
a heavy surface bloom are undesirable for marketing and such heavy blooming and such
heavy blooming can be depressed by grafting onto bloomless rootstocks.

49. Cucurbitaceae and linked with fig leaf gourd shown, that both uptake
(Masuda and Gomi, 1984; Tachibana, 1982, 1987) and transport (Choi et al.,
1995) of the macro-nutrients, particularly nitrate and phosphate, increased in
figleaf gourds compared with cucumber rootstocks in response to decreased
root-zone temperatures.
Among the micro-nutrients, Mn-, Cu-, and Zn-contents increased since
these are diminished strongly with decreasing temperature (Li and Yu, 2007).
Iron is not much affected by temperature and thus also not changed in cucumber
grafted onto fig leaf gourd.
Grafting as a tool to improve tolerance of vegetables to abiotic stresses
Thermal stress, water stress and organic pollutants
Dietmar Schwarza,∗, Youssef Rouphael b, Giuseppe Collac, Jan Henk Venemad

50. Grafting also influences flowering patterns. C. hardwickii grafted/gynoecious
cultivars of cucumber increases the expression of pistillate flowers.

51. Sicyos angulata a qualitatively short day wild species is induced to flower not only
by grafting it onto a flower induced plants of the same species but also by intergeneric
grafting on day neutral plants of cucumis or onto quantitatively short day plants of luffa
cylindrical under non-inductive long day conditions.
Besides it is found that S. angulata develops both staminate and pistillate
inflorescence with similar sex expressions even when one of the cucumber cultivars is
andromonecious.
CONT…

52.  Sacha Johnson, Patti Kreider, and Carol Miles, WSU Mount Vernon
Northwestern Washington Research & Extension Center
 Cushman,K.2006.Grafting Techniques for Watermelon. HS1075,
IFAS, University of Florida.
REFERENCE
 Friedlander, M., D. Atamon, and E. Galun. 1977. The effect of grafting
on sex expression in cucumber. Plant & Cell Physiol. 18:1343–1350
 Hartmann, H.T. and D.E. Kester. 1975. Plant propagation: Principles
and practices. 3rd ed. Prentice Hall, Englewood Cliffs, N.J
Handbook of Vegetable Crops L.C.De, S.K.Bhattacherjee
 Agrobios Vol x1, issue No.12, May 2013
Agrobios Vol x1, issue No.12, May 2013