Extent of fruit cracking in litchi and its control measures in Kangra Valley of Himachal Pradesh.
Chandel J. S., Sharma N. K.
Author Affiliation: Regional Horticultural Research Station, Jachh, Distt. Kangra (HP) 176?201, India.
South Indian Horticulture 40 : 74-78
Abstract : Fruit cracking in litchi can cause significant losses and is aggravated by high temperature, low RH and hot, dry winds. Studies of cultivars Dehra Dun and Calcuttia growing at low, middle and high altitudes and Dehra Dun growing with boundary windbreaks of Eucalyptus, seedling mangoes + Toona, and silver oak [Grevillea robusta] were carried out during 1990-91. Controls had no windbreak. The effects of spraying with different levels of ZnSO4 (0.5, 1.0 or 2.0%), boric acid (0.05, 0.10 or 0.20%) and NAA (10, 20 or 40 p.p.m.) from the pea stage to fruit maturity, and of applying irrigation at 20, 40 or 60% depletion of available soil moisture were also investigated. Maximum fruit cracking occurred at low altitudes, with mean values of 26.50% for Dehra Dun and 17.87% for Calcuttia. Cracking was significantly reduced by the presence of a windbreak, little difference occurring between species, although with Eucalyptus the yield was lower than in controls. Spraying with either ZnSO4, boric acid or NAA caused some reduction in cracking, the most significant being with 20 and 40 p.p.m. NAA. Irrigation at 20 or 40% depletion of available soil moisture also reduced cracking.