VEGETABLES –TOMATO
Origin
Tomato is originated in Peru of South America and name of crop came from the Aztec
word “Tomato”. The crop is of recent origin and first report of tomato was from Italy in 1544.
Later spread was fast and the crop is grown throughout the length and breadth of world.
Area and production
It is amazing to note the quantum jump in the spread of tomato during the last four
decades. In India, crop was grown in an area of 36000 ha. during 1960 and present area and
production in the country is 4.58 lakh ha. and 74.62 lakh tones respectively with a productivity of
16.29 t/ha. Leading producing states are UP, Karnataka, Maharashtra, Haryana, Punjab and
Nutritive value and medicinal use
Tomato occupies a prime position in list of protective foods since it is a rich source of
minerals like calcium (48 mg / 100g), sodium (12.9 mg), trace elements, copper (0.19 mg),
vitamins like vitamin A (900 IU), vitamin C (27 mg), vitamin B complex (thiamine), essential
amino acids and healthy organic acids like citric, formic and acetic acids. The attractive red
colour of fruit is due to lycopene and yellow colour is due to carotenes. Peculiar flavour of
tomato is due to presence of ethanol, acetaldehyde and a number of volatile flavour
components found in fruit. Different forms of tomatine, a steroidal glycoalkaloid, are identified
from various parts of plant. Tomato is a good appetizer and its soup is a good remedy for
preventing constipation.
Taxonomy
Botanical name of tomato is Solanum lycopersicum (lycos = wolf and persicon = peach).
Genus Lycopersicon is divided into two subgenera
a. Eulycopersicon (Red fruited and self compatible)
b. Eriolycopersicon (Green fruited and self incompatible)
Eulycopersicon includes two species, L. esculentum(Solanum lycopersicum) with large
fruits and L. pimpinellifolium ( New name Solanum pimpinellifolium) with small fruits born in
clusters. Eriopersicon mainly consists of wild sp like L. hirsutum(S.habrochaites), L.
peruvianum,(S. peruvianum) L. pissisi, L. glandulosum, L. cheesmani(S. cheesmani) etc.
Rick (1976) divided genus Lycopersicon into following two groups based on their ability
to cross with cultivated tomato:
Esculentum complex (crossable with cultivated tomato)
- L. esculentum, L. pimpinelifolium, L. cheesemani and L. hirsutum
Peruvianum complex (Not crossable with cultivated tomato)
- L. peruvianum, L. chinense.
Based on growth habit and fruit characters, five forms of L. esculentum are identified.
Communae - Common tomato
Cerasiformae - Small fruited cherry tomato
Pyriformae - Pear shaped tomato
Grandifolium - potato leaved tomatoFlowers are borne in racemose cyme and flower cluster is known as ‘truss’ ands its
position is extra axillary. Flowers are hermaphrodite, pendulous, pentamerous and
hypogenous. Stamens are six in number and inserted on throat of corolla tube and anthers are
convent around style.
Botany
Tomato is a true diploid with 2n=24. Plant is annual with herbaceous prostrate stem
having determinate or indeterminate growth habit. In the determinate growth, terminal bud ends
in a floral bud and further growth in arrested resulting in dwarf and bushy stature. In
indeterminate growth, terminal bud is a leafy bud and terminal anTomato is a self pollinated crop due to hermaphrodite flowers, introvert stigma, internal
and synchronized anther dehiscence, and stigma receptivity. Self fertilization occurs when
pollen grains are shedding during growth of style through anther corn.
Varieties
Quiet a large number of varieties differing in their climatic requirements, growth habit,
fruit quality, resistance to pest and diseases are developed for specific purposes like fresh
Varieties
Quiet a large number of varieties differing in their climatic requirements, growth habit,
fruit quality, resistance to pest and diseases are developed for specific purposes like fresh
Hybrid Vigour
Tomato is a classical example for exploitation of hybrid vigour in vegetables. Increasing
consumer demand, better emasculation and pollination processes, more seeds per fruit,
diversified use and scope for combining large number of favourable genes in F1 coupled with
easiness in cultivation makes the crop ideal for heterosis, breeding. Quite a large number of F1
hybrids with specific attributes like yield, earliness, uniformity, high quality, suitability to long
distance transport, storage and processing, adaptability to adverse conditions, resistance to
biotic and abiotic stresses have been developed by public sector research organizations as well
as private sector seed companies. With the adoption of new seed policy by the Government of
India in 1988, a large number of private seed companies entered in vegetable research and F1
seed trade. F1 hybrids developed and marketed by the private seed industry are now ruling in
many states like Maharashtra, Karnataka, Haryana, Punjab etc. Features of some public sector
tomato hybrids are given Table.
In addition, hybrids like Sun 496* (Sungrow seeds, Delhi), HOE 303*, Avinash 2*
(Syngeta), BSS 20*, Meenakshi, Tolstoi (Beejo Sheetal), NA 501*, NA 601* (Nath Seeds),
Sadabahar, Gulmohar, Sonali, MTH 6* (Mahyco, Jalna), ARTH 3*, ARTH 4* (Ankur Seeds),
Rashmi, Vaishali, Rupali, Naveen (IAHS, Bangalore), Swaraksha, Uttam (Namdhari Seeds,
Bangalore), Kt 4* (IARI, Katrain) etc. are a few hybrids popular among farmers.
Climate
Tomato is a day neutral warm season crop, which cannot tolerate frost. Cool and dry
weather is preferred by the crop and optimum temperature is 21-28o
C during day and 15-20o
C
during night. Night temperature is more critical than day temperature. High temperature results
in exerted stigma, dryness of stigma, burning of anther tip, poor pollen dehiscence, low pollen
viability and slow pollen tube growth leading to low pollination and fruit set. Incidence of viral
diseases also will be more at high temperature. Optimum temperature for colour development
of fruit is 21-24o
C. Development of colouring pigment, lycopene will be hampered above 27o
C.
Seed germination and pollen germination are adversely effected below 10o
C.
Based on night temperature requirement for fruit set, tomato varieties are classified into
three.
a) Normal set varieties: Set fruits at 15-20o
C.
b) Hot set varieties: Set fruits above 20o
C – eg : Philipine, Punjab Tropic, Pusa hybrid 1.
c) Cold set varieties: Set fruits below 15o
C – eg : Pusa Sheetal, Avilanche.
Tomato cannot withstand water logging. Hence well drained fairly fertile soil rich in
organic matter is preferred. It is moderately tolerant to acid soil having pH 5.5 and ideal pH
requirement is 6-7o
C.
Sowing time and seed rate
Under mild climatic conditions, where there is no danger of frost, three crops can be
raised in a year. In the hills, seeds are usually sown in March-April. In plains is grown during
June to November. Under Kerala condition, seeds are sown in September and transplanted in
October.
Seed rate
Open pollinated variety: 400-500 g / ha
Indeterminate F2 hybrid: 125-175 g / ha.
Seeds sown in an area of 4-5 cents (200-240 m2
) will be sufficient to plant one hectare.
Four to five weeks old seedlings are used for transplanting. Hardening of seedling is essential
for their establishment in main field and is done by withholding irrigation for one week before
transplanting, adding NaC1 (400 ppm) to irrigation water or by spray of cycocel (200 ppm) and
Zinc Sulphate (0.25%) + 25 ppm proline at time of transplanting.
Main field preparation and transplanting
Seedlings are transplanted on raised beds or on sides of ridges. Field is ploughed 4-5
times and raised beds of 80-90 cm width or ridges and furrows are prepared. Spacing depends
on the growth habit (determinate, indeterminate or semi determinate) of variety and various
spacing followed are 60 x 30-45cm, 75 x 60cm and 75 x 75 cm. Usually closer spacing results
in early and higher yield, but it may effect size of fruits.
Manures and fertilizers
Manure and fertilizer recommendation for tomato depends on the growth habit and
productivity of variety and it varies from state to state. In most of states, in addition to 15-20
tonnes of FYM, 100-125 kg, N, 50-60 kg P2O5 and 50-60 kg K2O are recommended for one
hectare. Recommendation for F1 hybrid is 250:250:250 kg NPK/ha.
FYM should be incorporated in soil at the time of final ploughing. 1/3 N, Full P and K
may be applied as basal dose either just before transplanting or 5-10 days after transplanting.
Remaining 2/3 N is applied 20 and 45 days there after. In Tamil Nadu, additional dose of 10 kg
borax and 5 kg Zinc Sulphate, as basal dose, are also recommended for correcting fruit
cracking and to increase yield and fruit quality.
Application of fertilizer in Tamil Nadu:
Apply FYM 25 t/ha, N 75 kg, P 100 kg, K 50 kg, Borax 10 kg and Zinc sulphate 50 kg/ha
as basal dose and 75 kg N/ha on 30th day of planting during earthing up. Spray 1 ppm (1 mg in
one lit) Triacontanol, 15 days after transplanting and at full bloom stage to increase the yield.
Irrigation
Furrow irrigation is the most common method in tomato and the crop require adequate
moisture throughout growth period. Frequency of irrigation depends on the climatic and soil
conditions. During summer, crop should be irrigated at 3-4 days interval. Water stress at
flowering stage will adversely effect fruiting and productivity. A long spell of drought followed by
heavy irrigation leads to cracking of fruits. Similarly a dry spell after regular irrigation causes
blossom end rot. Drip irrigation and sprinkler irrigation are becoming more common in areas of
water shortage.
Inter-cultivation
Field should be kept weed free by frequent weeding, hoeing and earthing up.
Application of pendimethalin (1.0 kg a.i. / ha) as pre emergence spray along with one hand
weeding at 45 DT is ideal for tomato variety Pusa Ruby. Oxyfluorfen (0.25 kg a.i. / ha) Goal
(0.25 kg a.i./ha) and Basalin (1.0 kg a.i. / ha) were also ideal as pre emergence application.
Post emergence spray of Sencor (0.5 kg a.i./ha) was also effective at the All India Coordinated
trials. Mulching with straw or plastic is also effective for weed control and for regulating soil
temperature.
Training and pruning
All indeterminate varieties are trained with wires, strings or stacks to prevent lodging and
loss of fruits by coming in contact with soil. It is done by providing individual stack or by erecting
2-2.5 m long poles on either side of ridges for stretching G1 wire. Branches of plants are
supported on poles or strings with twine.
Pruning is also generally followed in indeterminate varieties to improve size, shape and
quality of fruits. It is removal of unwanted shoots to enhance vigor of plants.
Harvesting
Crop starts yielding by 70 days after planting. Usually fruits are harvested with hand by
a gentle twist so that the stalk is retained on plant. Intervals of harvests depend on season and
it is twice in a week during summer and weekly during winter and rainy days. Harvesting
maturity depends on the purpose whether for fresh market, processing, long distance transport
etc. Following maturity standards are recognized in tomato:
• Mature green: Fruits fully grown, fruit colour changes from green to yellowish and cavity
filled with seeds surrounded by gelly like substance. Harvested for long distance
market.
• Turning or breaker stage: Fruits firm, 1/4th portion of fruit changes to pink in colour, but
the shoulder still yellowish green. Harvested for long distance market.
• Pink stage: 3/4th of whole fruit surface turns pink colour. Harvested for local market.
• Light red: Entire fruit surface is red or pink but the flesh is firm. Harvested for local
market.
• Red ripe or hand ripe: Fully ripened and coloured. Flesh becomes soft. Harvested for
processing and for seed extraction.
Yield
Open pollinated varieties : 20-25 t/ha.
F1 hybrids : 50 t/ha.
Grading storage and marketing
Fruits after harvesting are graded and packed in bamboo baskets or wooden boxes.
Four grades specified by Bureau of Indian Standards are Super A, Super, Fancy and
Commercial. Since tomato is a climatic fruit, good care should be taken to remove bruised,
cracked and damaged fruits before packing in baskets. Though tomato can be stored at low
temperature, commercially it is not stored in cold storages in the country due to practical
reasons. Fruits can be stored for-two weeks and four weeks at 10-13o
C when harvested at red
stage and green stage respectively. Pre-cooling of fruits before storage and transportation
enhances storage life.
Processing tomatoes
Use of tomato for processing is increasing day by day and a variety of products like
puree, paste, syrup, juice, ketchup etc are made. Varieties for processing should have following
qualities.
• Deep red colour which retains even after processing.
• Low pH – The acidity of fruits affect-heating time required for sterilization of processed
product. Longer time is required if pH is high and hence a pH below 4-5 is required for
processing.
• High TSS – Fruits with high TSS yield more finished products / tonne of raw fruits and
hence minimum TSS should be 4.5o
B
• High viscosity and consistency
• Firm and easy peeling
• Pericarp thickness-should be more than0.5 cm.
• Crack resistance
• Fruits size should be above 50 g and oblong in shape
Varieties like Pusa Gaurav, Roma, Punjab Chuhara, Pusa Uphar, Arka Saurabh are
specially suited for processing.
Physiological disorders
Fruit cracking
Fruit cracking is caused both by genetic and environmental factors. Following four types
of cracking are noticed tomato.
• Radial Cracking: Usually seen at ripe stage and crack radiate from pedicel end to stylar
end.
• Concentric cracking: Seen around shoulder of fruit even at green stage.
• Cuticular: Seen on outer skin of fruit.
• Burst: Burst occurs at certain points on shoulder of fruit.
Radial and concentric cracking are more common of which, former is more damaging. A
long spell of drought followed by sudden heavy irrigation may cause cracking. Wide variation in
day and night temperatures and high humidity also cause fruit cracking.
Many crack resistant varieties like Crack Proof, Ohio 832, Sioux, Manulucie, Anagha etc.
were developed at various research organizations. Fruits of crack resistant varieties have thick
pericarp or cuticle and fruit skin with high elasticity and less acidity. Pectin content in resistant
varieties ranges from 0.8 to 1.6% compared to 0.54% in susceptible ones. High pectin
concentration makes fruit less rigid and more pliable.
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