Tomato (Lycopersicon esculentum) is an annual plant grown extensively in the world mainly for vegetable purposes. It ranks second in importance next to potato & is warm season crop rich in minerals, vitamins and organic acids. It is very good appetizer and its soup is good remedy for patients suffering from constipation. It is known as poor man`s orange.
Tomato is said to be originated from Tropical America (Thompson and Kelly) from where it spreads all over the world and it became popular in Nepal within last six decades.
Tomato is warm season crop that is extremely susceptible to cold winds, frost and water logged condition. Flowering and fruit setting are best at a day temperature of 25 degree Celsius and night temperature of 18 degree Celsius. Below 10-degree Celsius fruits are unable to develop red colour.
Climate and Field Preparation:
Tomato can be grown in wide range of soil ranging from sandy loam to heavy clay but good yield is obtained in well drained rich in organic matter and having better irrigation facilities. The best soil pH is 6.0-7.0 and liming is mandatory if soil is acidic. The soil should be ploughed thoroughly to bring fine tilth. Generally, 4-5 ploughing is needed to make the soil friable followed by planking.
For successful crop, application of about 20 tons of FYM, 200 kg N, 120 kg P, 100 kg P per hectare is required. One third of N & all phosphorus, potassium and FYM should be applied during field preparation whereas 1/3 Nitrogen should be applied 25-30 days after transplanting and the remaining should be applied only after 45-50 days of transplantation. Similarly, application of 20-30 kg of Borax and 0.5% Zinc is beneficial for yield and good quality of fruits.
About 225 square meter is required to raise seedling for one hectare. Nursery beds are prepared with 7.5 m length, 1 m width and 10-15 cm height. Treatment of seed with fungicide like Captan, Thiram @2g/kg seed is essential. Soil solarization is essential to reduce pest and disease incidence. For this, cover the nursery bed with transparent polythene sheet for at least 10 days during day time. Sow the seed in line and cover the bed with low tunnels and low-cost poly-house. Irrigate the bed in the evening regularly. Spray Diathane M-45 @ 0.25% every week if necessary, to prevent post emergence damping off.
400-500 grams seed is needed for raising crop in 400-500 gram. 125-175 grams hybrid seeds are required for planting in one-hectare land.
Time of planting of tomato in different geographical regions are as below:
|Geographical domain||Season||Nursery sowing||Transplanting|
|Frost free area||Spring/Summer||Late November||January|
Seedlings are ready for transplanting between 4-5 weeks after seeding in nursery beds. Hardening is necessary before transplanting. It is done by withholding watering for 4-5 days. The tomato seedlings are transplanted on flat beds or on the side of ridges.
Spacing is according to the crop type.
Indeterminate type: 75 cm * 75 cm or 75 cm * 60 cm
Determinate type: 60cm * 45 cm or 60 cm * 60 cm
First irrigation is required soon after transplanting. Irrigate the crop at 3-4 days interval during summer and 10-15 days interval during winter to maintain soil moisture moderately. A prolonged drought followed by sudden heavy irrigation cause fruit cracking.
Training and Pruning:
Pruning and training is followed in indeterminate type of tomatoes. Pruning improves the size, shape and other qualities of fruits. It breaks apical dominance, eliminates the crown set and enhances the plant vigor. Plants are trained with wires, strings, or stakes.
Inter-culture and Weed control:
Weed control is by two hand hoeing at 14th day and 42th days after transplanting and an earthing up operation at 28th day after transplanting. Pre-emergence application of Metribuzin @0.35 kg/ha, Fluchloralin @1.25 kg/ha has been found to increase the yield significantly over hand weeding.
Plant Growth Regulators:
Plant growth regulators have been found beneficial for yield, quality and resistance to Tomato Leaf Curl Virus.
- Seed treatment with Beta-napthoxy-acetic acid (BNOA) @25-50 ppm, Gibberellic acid @ 5-20 ppm were reported to improve in growth and yield of tomato.
- Seedling soaked for 24 hours in NAA @ 0.1 ppm showed higher fruit set, early maturity and increased total yield.
- The foliar application of PCPA (Parachlorophenoxy acetic acid) @ 50-100 ppm at the flowering stage increase the fruit at low and high temperatures.
Harvesting and Yield:
In indeterminate cultivars, fruits can normally be harvested 70-100 days after planting while determinate cultivars may begin fruiting at 70 days depending on the environmental condition.
It can be harvested at following stage:
Green`s stage: Suitable for sending to distant markets and fruit is fully developed.
Beaker stage: Color changes from green to yellow with pink or red skin covering not more than 10%.
Turning stage: 10-30% fruit surface turn to pink or red.
Pink stage: 30-60% portion in red or pink and fruit is not fully ripe. Suitable for local markets.
Light red: 60-90% fruit surface turn to red.
Red: >90% surface turn to red. Fruit develops maximum color. Suitable for processing purposes.
Fruits picked at 4-5 days interval in summer whereas for winter picking is at weekly interval.
Yield ranges from 20-25 tons/ha and hybrid varieties may yield upto 50 tons/ha.
Storage and marketing:
Tomato can be stored successfully at 12-14 degree Celsius and 90-95% RH for 7-21 days. Fully ripe fruits can be stored for 4-7 days in 8-10 degree Celsius and 90-955 RH. Wooden boxes are generally used for packing for long distance markets.