Nitrogen, phosphorus and potassium fertilization in 'Cricket Ball' sapota (Manilkara achras)

An experiment was conducted during 1996-2001 at Kaul, Haryana, to study the effect of different levels of N, P and K on growth, yield and quality of 7-year-old 'Cricket.Ball' cultivar of sapota (Manilkara achras Mill.). The. treatments were 3 levels of N (400, 800 and 1 200 g/tree) and 2 of each of P2O3 and K2O (260 and 400 g/tree). Per cent increase in tree height and stem girth was higher with the higher levels of N,P and K application. However, the increase was non-significant with higher K level. Application of 800 g N/tree gave the highest pooled yield (38.81 kg/tree) as well as during all the years of study, with maximum fruit weight (76.8 g) and total soluble solids (19.3degreesB). Higher levels of P and K also increased the fruit yield significantly. Different levels of P and K had non-significant effect on fruit weight and total soluble solids of the fruits. None of the nutrient elements could affect the fruit acidity. Interaction effects of N, P and K on pooled fruit yield and fruit weight were significant. A combination of 800 g N, 400 g each of P2O5 and K2O/tree resulted in the maximum fruit yield (43.88 kg/tree) of heaviest fruits (78.50 g).