MANAGING SOIL FERTILITY

Farmyard manure should be applied at the rate of 25 tonnes/ha several weeks before sowing. Green manure with crops like sunhemp (Crotalaria juncea), cowpea (Vigna catjang), daincha (Sesbania aculeata) and cluster bean (Cyamopsis tetragonoloba) can also be used to substitute for farmyard manure to an extent. Neem cake can be applied @ 150–250 kg/ha. Top dressing can be given with groundnut cake (@ 80–100 kg/ha) after 40 days of sowing. This will help in increasing the yield as well as the size of fruits. The soil can also be enriched by using vermicompost or biodung compost as additional supplements.
Plant vigour can be further stimulated through bio enhancers, viz., amrut pani/jeevamrut introduced through irrigation water and foliar spray of BD/BD liquid manures.

Intercrops and crop rotation

The nutrients present in the soil get depleted when the same crop is continuously cultivated. A particular nutrient taken up largely by a single crop gets reduced/depleted from the soil. To avoid this, crop rotation should be practised. This not only helps to retain the nutrients in the soil but also improves the fertility.
Intercrops like spinach, radish, pulses and oilseeds can be grown with tomato. Cropping systems like okra-tomato, tomato-onion are popular in various parts of India. Non-solanaceous crops like rice, maize, sorghum, wheat, millets, cabbage, cauliflower, radish, watermelon, onion, garlic, groundnut, cotton, safflower, sunflower and sesame can be grown after the tomato crop. A gap of at least one year should be allowed between two solanaceous crops such as tomato, chili, brinjal, capsicum and potato.

There is a practice of growing marigold along with tomato for controlling fruit borers and mosaic disease. For every 16 rows of tomato, a single row of marigold should be sown as a trap crop. The marigold nursery should be raised 15 days before the tomato nursery. When planting is undertaken, the marigold seedlings would be 40 days old and tomato seedlings would be 25 days old. This would facilitate synchronous flowering in marigold and tomato. Marigold attracts female fruit borers. The female lays the eggs on the marigold flowers which can be manually collected and destroyed.

Training and pruning

Plants with an indeterminate habit need to be pruned to one or more stems and trained on stakes. Axillary shoots should be removed every week leaving behind well placed lateral shoots. The growing tips should be pinched off when the plants are 1.5 metres tall. This reduces the incidence of soil borne diseases and results in an early harvest with large and clean fruits.

Staking

Staking is needed for hybrids which are generally of tall stature and heavy bearers. It also makes intercultural operations easier and helps in maintaining the quality of fruit. The plants are staked 15– 20 days after transplanting or when they are 15–25 cm high. Staking can be done either by using individual wooden stakes or by pulling overhead wires to which the individual plants are tied. For indeterminate types, two or three wires can be stretched parallel to each other along the crop rows and the plants tied to them.

Special techniques

Trenching to increase yield : When tomato plants fail to produce flowers and fruit, a small trench can be dug around the area to destroy the weeds. The plants can also be deprived of water and allowed to wilt for a day. Later, when the crop is irrigated, they will start to flower.

Application of tank silt : Application of tank silt @ 25 tonnes/ha to irrigated tomato supplies micronutrients that build resistance to pests and also saves expenditures on plant protection.

Prevention of flower drop : When there is excessive flower drop, a spray of neem seed and cow dung mixture can be given. To prepare this mixture, five kilograms of neem seed are ground well and diluted with water and then filtered. Twenty-five kilos of fresh cow dung are mixed thoroughly with this filtrate. The resulting product is sufficient for spraying on one hectare of land provided one adds the required quantity of water. The spray will stop flower drop.

Increasing market quality : Application of silt and red soil followed by eight tonnes of farmyard manure per hectare in two installments, (once at the time of transplantation [100 kg] and another at the time of flowering [100 kg]) to the tomato nursery controls soil borne pests and diseases. Such an application is also found to impart an attractive colour to the tomato and to result in an increase in its size.

Updated on : Dec 2014