Organic cultivation of tomato

Th Robindro Singh / T Medhabati Devi / Prof M Premjit Singh *

Sale of Tomato at a market at Moreh, a border town adjoining Tamu in Myanmar in 2008

Tomato is very popular for its taste and nutritive value. It is used for soup, salad, pickle, ketchup etc. It contains protein, fat, minerals, carbohydrate, vitamin A, vitamin B1, Calcium, Phosphorus, Sulphur, Iron etc. A tomato cannot stand frost. It grows well under an average temperature of 180C to 270C.

In Manipur, it grows whole the year-round, but the best season for cultivating tomatoes organically is during the rabi season, as pest and disease problems are comparatively low during winter.

Conversion Plan

In order to cultivate tomato organically, a buffer zone of 7.5 to 15 m shall be maintained, if the neighbouring farms/ fields are non-organic.

Variety

Arjuna, Avinash 2, Sloux and Arka Shrestha are recommended varieties for organic cultivation.

Nursery management

Adopt raised nursery beds about 10 cm high beds for good drainage, thereby preventing soil-borne fungi. Soil solarization may be done using transparent polythene sheets (160-100 gauge thick) for about 15-21 days. The soil may be mixed with the bio-agents like Trichoderma harzianum @10g/kg FYM to protect the seedlings from seed-borne and medium borne diseases like damping off, collar rot etc.

Azospirillum and Phosphorus Solubilizing Bacteria (PSB) are to be mixed with the nursery @10g/kg FYM. Hardening off seedlings is to be done by slightly reducing watering 3 to 4 days before transplanting at 20 days and exposing them directly to sunlight 1-2 days before transplanting thoroughly water the seedlings about 12 hours before transplanting in the field.

A good seedling will have 4 to 5 leaves (about 4 weeks old), vigorous and stocky. Seedlings are drenched with Pseudomonas fluorescens 20% (10g/lit.), for 15 minutes before transplanting to the main field to prevent foliar diseases.

Land preparation and transplanting

The soil in the field is brought to a fine tilth and the entire quantity of enriched FYM (40t/ha) is incorporated into the soil before transplanting. Ridges and furrows are opened at 1m spacing and need cake is applied while forming ridges @ 250 kg/ha.

Wider spacing of 100 cmx50 cm (20,000 plants/ha) is recommended for organic cultivation of tomato for better aeration and to minimize the rapid spread of foliar diseases. The field is irrigated lightly and seedlings are transplanted at a spacing of 50 cm along one side of the ridge by making a hole.

Twenty-five days old healthy seedlings are transplanted preferably in the morning hours or in the late afternoon to minimize transplant shock and for better establishment of the transplants.

Nutrient management

Well decomposed FYM is thoroughly mixed with Trichoderma harzianum, Azotobacter or Azospirillum and Phosphate Solubilizing Bacteria (PSB), all @ 1kg/tone of FYM @ 2kg/sq. m. to be applied 15 days before planting.

This enriched FYM should be mixed with 10 tones of FYM before applying to the field. After the addition of bio inputs, the FYM is to be moistened and incubated for 15 days under a plastic sheet. Application of FYM @ 10t/ha and Vermicompost @ 2.5t/ha is reported to yield about 240q/ha.

Water management

Tomato is most sensitive to water deficit during flowering, somewhat sensitive immediately after transplanting and during fruit development. For good crop growth, well-timed furrow or drip irrigation is effective. Wilting in the late morning indicates that the crop should be irrigated.

As a general rule during the dry season, irrigate at an interval of 3-4 days for the first month after transplanting and then every 5-7 days interval until crop completion. Tomato plants are sensitive to waterlogging and hence, flooded fields should be drained immediately.

Weeding and earthing up

First, weeding can be done at 20 days after transplanting and second weeding 45 days after transplanting coinciding with earthing up operation. Mulching with farm residues like grasses or fallen leaves etc will help in preventing the weed growth besides conserving the moisture.

Plant protection

Apply need cake @ 250 kg/ha treated with Trichoderma harzianum @2.5 kg/ha in the main field against Fusarium wilt and seed-borne diseases. Drench the nursery bed with 2% Trichoderma culture and spray the plants with 1% Bordeaux mixture against diseases.

For the management of foliar diseases (leaf spot and powder mildew) and fruit rot any of the bioagents viz., Trichoderma harzianum, Pseudomonas fluorescens, and Bacillus subtilis @ 10g/lit. each can be used one at a time at an interval of 10 days once the infestation is reported.

For the management of bacterial wilt, use of tolerant variety and seedlings treatment with Pseudomonas culture (20%) for 15 minutes before planting is suggested for tackling Bacterial wilt problem. For the management of insect pests, bioagents viz, Beauveria bassiana, Verticillum Licanii and Metarhizium anisopliae 10g/lit. each can be used one time at an interval of 10 days.

Tomato fruit borer can also be managed by spraying NPV like Helivax @ 1ml/lit. of water. Trap crop like Marigold (2 rows after every 16 rows of tomato) is recommended.

Harvesting and Yield

Fruits are to be harvested at breaker stage when pink colour appears and pickings are to be done regularly at 3-5 days interval. Harvest during cool periods such as early morning or late evening provides shade to harvested fruit and avoids exposing the fruit to a temperature higher than 250C.

If possible, store the fruit in a ventilated place with a relative humidity range of 85-90% to reduce water loss. About 50 to 60t/ha of marketable yield can be obtained by a good organic production biotechnology system.

For further details contact:-
Public Relation & MediaManagement Cell,
CAU, Imphal