Tropical and subtropical vegetables (2+1)

Preparation of field

• Soil should be worked well upto a depth of 20-25 cm and made into a fine tilth before seed sowing. The plant has well developed tap root system and is a heavy feeder and as such the soil should be made rich in organic matter content. Application of 25 t/ha of FYM is needed for obtaining good crop. Solarisation during hot summer months helps to great extent in controlling weed pest population.

Spacing
A plant distance of 60 X 30 cm accommodating 5000 plants/ha is recommended for branching types, while 45 X 30 cm accommodating 66,000 plants/ha for non branching type. During spring summer season with less plant growth these spacing is kept at 45 x 20 cm or less. The seed should be sown at a depth of 2.5cm.

Nutrition
The quantity of manures and fertilizers depends upon the type of soil, but in normal condition 25 tonnes of FYM should be added at the time of last harrowing. In addition to this, 125kg N, 75kg P and 63 kg K/ha will be required in medium type of soils. Half of the nitrogen and full amount of P and K should be applied as basal dose while remaining half of the N should be given as top dressing 35-40 days after sowing the seeds. Positive effects of zinc up to 2% as soil application or 2mg/litre of foliar spray of molybdenum @20mg/l foliar spray have been observed on fruit yield and appearance.

Irrigation
During kharif, irrigate the crop as and when required. In summer season the crop should be irrigated at an interval of 5-6 days. Flooding of plants should be avoided. Drip irrigation increases considerable yield and saves 70-80% irrigation water.

Weed control
About two weedings are required till the crop canopy covers the soil surface. Use of weedicides has helped in reducing the numbers of weeding to zero during summer and one during kharif season. Fluchloralin @1.5kg a.i/ha as pre sowing soil incorporation and alachlor @ 2kg a.i/ha as post sowing gives control of weeds. The soil surface application of weedicides is effective for 4-5 weeks.

Use of chemicals and growth regulators
The highest average fruit set and yield were obtained with cycocel at 100 ppm as seed soaking for 24hrs on seed treatment by GA (400 ppm), IAA (200 ppm) or NAA (20 ppm) enhanced germination, ethephon (100-500ppm) reduced vegetative growth and weakened apical dominance, post harvest treatment with cycocel (100ppm) enhanced shelf life of fruits and with ascorbic acid (250 ppm) retention of chlorophyll was the best.