Protected cultivation of Tomato in Sikkim

Sikkim is gifted with suitable climates for round the year tomato cultivation. It is cultivated in the open field during rabi season and under protected condition during summer and rainy season.

Protected structures

The main purpose of protected cultivation is to create a favorable environment for the sustained yield as to realize its maximum potential even in adverse climatic conditions. The protected structures may be a high cost or low cost polyhouse, net house, tunnels etc. a partially ventilated low cost polyhouse with both polythene and agroshed net may be suitable for farmers.

The site for protected cultivation should be accessible, sunny, with no water-logging. To minimize the diseases, new area should be selected for cultivation. The soil should be well-drained, loamy with adequate organic matter (> 2.0%). Crops are successfully grown in the moderately acidic soils (pH 6.0- 7.5). The pH can be maintained by adding lime/dolomite @ 100g/m²

Climate

Tomato prefers moderate temperature and thrives well in the temperature range of 25 – 30^oC. The prevalence of low temperature and high humidity causes severe infestation of diseases.

Nursery management

Seeds are sown in raised beds under protected structures. Seeds can be sown about 20 – 25 days before planting. The average seed rate for tomato is 350 – 400 g/ha. Seeds are sown with row spacing of 10 cm and seed spacing of 0.5cm. Densely populated seeds produce weak seedlings. The beds should be drenched with Trichoderma+ Pseudomonas culture @ 2 % to manage damping off.

Varieties

Indeterminate tomato varieties are suitable for cultivation under polyhouse. Avtar, Indam Hybrid, All Rounder, Arka Meghali, Arka Surabhi, etc. are suitable varieties for tomato Indeterminate tomato varieties are suitable for cultivation under polyhouse. Avtar, Indam Hybrid, All Rounder, Arka Meghali, Arka Surabhi, etc. are suitable varieties for tomato cultivation.

Planting

Tomato should be planted on the raised bed with the bed width of 1.5m. There should be a path of 0.6m between two beds. 20 – 25 day old seedlings should be planted at the distance of 1.0 x 0.8m. Before planting, the root of seedlings should be dipped for 15 minutes in Trichoderma + Pseudomonas culture @ 10%. Planting should preferably be done in small pits for better root development.

Nutrient Management

The nutrient requirement of tomato is moderately high ( N 100, P 60, K 80 kg/ ha) and shows good response with the addition of nutrients. FYM should be applied @ 5.0 kg/ m² along with neem cake @ 200g/ m². At the time of planting, seedling should be treated with Azospirillum + PSB (20%) for 15 minutes. The addition of vermicompost @ 1 kg/ m2 further improves the production.

Interculture and irrigation

Tomato is a shallow rooted crop and roots are restricted within 15 – 20 cm of soil. So, light earthing up should be done after 30 days and 45 days of planting. Good quality water should be applied at 10 days interval. The plants should be provided with strong multiple stakes after one month of planting.

Diseases and Pests

Late blight

Late blight of tomato is the most devastating disease caused by a fungus Phytophthora infestans. It infects and destroys the leaves, stems and fruits. Its infection is most rapid during conditions of high moisture and moderate temperatures (20-25^oC).

Management

• Nursery - Soil treatment with Trichoderma culture @ 2%
• Soil drenching with Trichoderma culture @ 2% before planting
• Seedling treatment with Trichoderma culture @ 10% for 15 minutes
• Soil drenching with Bordeaux mixture (1:1:100) after 15 days of planting
• Spray of Bordeaux mixture (1:1:100) at fortnightly interval after one month of planting.
• In severe infection, application of Ridomil/Matko @ 2g/ l manages the diseases effectively.

Early blight

Early blight of tomato, caused by the fungus Alternaria solani, is a common foliar disease of tomato. This disease causes direct losses by the infection of fruits and indirect losses by reducing plant vigor. The disease can be managed by spray of Bordeaux mixture (1:1:100).

Grey mould

Grey mold a fungal disease (Botrytis cinerea), is an important disease of tomato and its infection occurs after flowering and fruit set. In case of severe infection, flowers and pedicel starts dying and in later stage fruits also start rotting. The infection starts from peduncle edn and infected fruits are not suitable for consumption.

Management

Application of Bordeaux mixture (1:1:100) after one month of planting. In case of severe infestation, spray of Kavach (Clorothalonil) @ 1.5 g/ l minimizes the infection.

Cercospora leaf spot

It is one of the important foliar disease caused by Cercospora sp. Infected leaf has brown spots with curled leaf margin and late on, it withers. As the disease progresses, the leaflets turn yellow and also with curled margins. Spots on the leaf petioles, stems and flower parts become elongated and have dark – brown color. In heavily infested plant, defoliation may occur. The disease can be managed by the application of Bordeaux mixture (1:1:100)

Fruit borer

Fruit borer (Helicoverpa armigera) is the most important pest of tomato. It causes serious damage during the fruit development and ripening. The larva feeds on the pulp by making hole. The infested fruit is not suitable for consumption.

Management

Application of NPV (Helicide) @ 0.5 ml/ l after 15 days of fruit set.

Yield

The average yield of tomato under protected condition may vary between 6 -8 kg/ m² if proper care is taken. The average yield per plant may be 3 – 4 kg/ plant with the fruit number of 40 – 60 / plant and fruit weight 80 – 90 g.

Profitability

The cultivation of tomato is highly profitable if fruits are harvested between June -October. The cost of cultivation may vary from Rs 20 – 25/ m², while the earning may be between Rs. 100 – 130 / m². The cost benefit ratio in tomato is generally as high as 1:4.

Source: Kundan Kishore, Scientist (Hort.), Ashok Kumar, Scientist (Hort.), H.Kalita, Sr.Scientist (Hort.), Tasvina R Borah, SMS (KVK), Monika N, RA (MM-1), Brijesh Pandey, RA (MM-1), ICAR Research Complex for NEH Region,
Sikkim centre