This document summarizes a study that isolated and characterized fungi associated with spoiled tomatoes. Samples of spoiled tomatoes were collected from five locations in Gwagwalada, Nigeria. All samples showed 100% prevalence of fungal growth. Morphological analysis identified the fungal genera Aspergillus, Cladosporium, Fusarium, Mucor, Penicillium, and Rhizopus. Statistical analysis confirmed that fungi were responsible for the tomato spoilage. Fusarium species were the most commonly occurring fungi identified. Proper handling, transportation, and washing tomatoes with clean water can help reduce fungal spoilage.

1. ISOLATION AND CHARACTERIZATION OF FUNGI ASSOCIATED
WITH SPOILED TOMATOES
INTRODUCTION
Vegetables constitute commercially and nutritionally important
indispensable food commodity. Vegetable naturally play a vital role in human
nutrition by supplying the necessary growth factors such as vitamins and essential
minerals in human daily diet and that can help to keep a good and normal health.
Vegetables are widely distributed in nature. One of the limiting factors that
influence the fruit economic value is the relatively short shelf-life period caused by
pathogen’s attack (Droby, 2006: Zhu, 2006).
Tomato (Lycopersiconesculentum) pronounced Toh-MAH-to is the most
important vegetable worldwide. Tomato is an annual plant which belongs to the
Solanaceaefamily which includes other well-known species such as Potato,
Tobacco, Pepper and Egg plants (aubergine) and can reach a height of over two
meters. It’s a berry fruit, tomato is grown mainly in soil (Frazier and
Westhoff,2004).

2. Tomato is essential mainly for its dietary needs and can be consumed in
diverse ways. It can be cooked as vegetable, as an ingredient in many dishes and
sauces; in the making of stew, fruit juices and can be eaten raw in salads(Masefield
et al., 2002).
The modern day tomatowhich is a very popular fruitoriginated from South-
Western Hemisphere, now the Peru-Euador area(Rick,2001).From here,it was
distributed to many parts of tropical America. It possibly arrived the West African
Ports via Portuguese traders or the Sudan (Tindall, 2004).
Tomato in West Africa is grown in gardens and irrigation schemes. In Nigeria,
most tomatoes are grown in the northern parts of the country(Erinle,2007) and
there is no record of any systematic or organized traditional storage method for
vegetables and fruits. They are usually sold immediately after harvesting. They are
packed in baskets, cardboard boxes, or wooden crates ready for transportation to
the markets.
Tomato is the most perishable vegetable during handling, transportation and
storage. This is because tomato contains large amount of water which makes them
susceptible to spoilage by the action of microorganisms such as fungi, bacteria and
protozoans (Ross, 1975). Estimates have shown that about one third of the produce
is lost before reaching the consumer (Erinle, 2007), this loss has been attributed to
a number of factors which include physical (mechanical breakage, bruises),

3. physiological and also damages caused by pathological agents (Thompson and
Kelly, 2000), market value of the tomato are mainly reduced by this factors.
Watt and Merrill, (2000) defined spoiled food as that which have been damaged or
injured so as to render it undesirable for human consumption. Various activities
may result in food spoilage: insect activities,causing physical injuries for example,
bruisingand enzyme activity by microorganism causes change in colour, taste,
smell, texture and quality of the food.
Pauland Sarisbury, (1981) also referred to spoilage as any change in the
condition of food in which the food becomes less palatable or even toxic: these
changes may be accompanied by alteration in taste, smell, appearance or texture.
The spoilage of food by microorganisms should not be viewed as a sinister
plot on the part of the microbes deliberately to destroy foods but as a normal
function of these organisms in the total ecology of all living organisms (Watt and
Merrill, 2000). It has also been estimated by Watt and Merrill (2000) that 20% of
all fruits and vegetables harvested for human consumption are lost through
microbial spoilage causing one or more of 250 market diseases. Spoilage of fresh
tomato usually occurs during storage and transit and also while waiting to be
processed.

4. Frazier and Westhoff,(2004) reported that fruits and vegetables after picking
continue to respire and as a result heat is produced, this heat is known as ‘vital
heat’, the amount which varies with particular amount of fruits and vegetables.
Vegetables that respire more thereby generating most heat are those that
perish/spoil most rapidly (Wheeler, 2005). The resulting respiration of the fruits in
addition to the normal ripening process complicates an independent discussion on
microbiological spoilage of fruits in general and tomato in particular.
Fusarium oxysporium f.sp.lycoperisici andVerticilliumalbo-atrumare two
fungi that cause similar wilt disease on tomato.(Nesmith etal.,1983). Fusarium is
more common in replant fields and gardens while Verticilliumhas been destructive
on greenhouse tomatoes and in commercial stake tomatoes. Verticillium wilt is
more of a problem at cooler temperature while Fusarium wilt is considered a warm
temperature disease. Both are favoured by wet conditions.
According to Nesmithetal., (1983), both fungi are common inhabitants of
Kentucky soils. These fungi attack the plant through the roots and grow up through
the water-conducting vessels. FusariumandVerticilliummay be introduced to soils
in several ways: Old crop residues, transplants, wind, water,implement-borne soils
or mulches. These fungi become established readily in most soils and can remain
in the soil for years. When susceptible tomatoes are planted, in infected soil, their

5. roots are also subjected to attack by these fungi. Both diseases are much more
serious when accompanied by root knot nematode. These problems can be
controlled by using resistant tomato varieties and fumigating or stream sterilizing
greenhouse soils.
ABSTRACT
The study examined the various fungal pathogens associated with tomatoes
spoilage as well as their preliminary taxonomic grouping up to genus level. 25
samples of the spoiled tomatoes were collected from five locations within
Gwagwalada area council. Locations include: Passo Village, Gwagwalada market,
Phase III, New Kutunku and Dagiri. Thesame prevalence rate(100%) was recorded
for all tomato samples purchased in all locations.The level of awareness of the
general public in regards to the spoilage of tomatoes by Fungi was very significant
with about 62.5% of the respondents attesting to the claim of tomato spoilage
caused by Fungi and 37.5% disagreeing. Morphological studies reveal the fungal
members which include members of the genus Aspergillus, Cladosporium,
Fusarium, MucorPenicilliumand Rhizopusspecies. Species of Fusarium were seen
to be the most occurring in all samples. Satistical analysis also concurred to the
fact that fungi are responsible for spoilage of tomatoes purchached in Gwagwalada
(p< 0.05). It implies that fungi are greatly responsible for tomato spoilage. Proper

6. handling, transportation and thorough washing with clean or chlorinated water will
go a long way in reducing the risk of tomato spoilage by Fungi.
Editor source: Isolation And Characterization Of Fungi Associated With Spoiled
Tomatoes In Gwagwalada