Control of fruit cracking and sun-burning in litchi by irrigation and moisture conservation.

摘要

India is the second largest producer of litchi in the world. In West Bengal, the litchi cultivation is based mainly on one cultivar 'Bombai'. The litchi harvesting period in West Bengal coincides with high day temperature at 35-40 degrees C and low relative humidity at 60-70% which causes 10-25% crop loss due to fruit cracking and sun-burning. This causes considerable loss for the litchi growers. The objective of the present study was to test the effectiveness of different micro-irrigation systems and placement of dessert cooler in the orchard to increase humidity in the orchard and soil moisture conservation by mulching to minimize the disorders. Drip irrigation treatments at 20 and 40% pan coefficient, combination of drip irrigation at 20% pan coefficient with placement of dessert coolers in the orchard at 15 days before anticipated harvesting, mulching the tree basin with fallen litchi leaves and preharvest bagging and irrigation with overhead sprinkler at 40% pan coefficient were compared. The results revealed that irrigating the orchard at 20% pan coefficient and placement of dessert cooler or by irrigating the orchard though overhead sprinkler completely control fruit cracking. Least incidence of sun-burning of 1.67% was observed by irrigation at 20% pan coefficient. However, irrigation at 20% pan coefficient+mulching caused maximum fruit weight of 27.30 g and irrigating by overhead sprinkler system showed the highest aril recovery of fruit at 74.72%.