Effect of nitrogen on growth, fruit yield and quality of guava under rainfed conditions of Bihar plateau

An experiment was carried out in 5 years old guava cv. Allahabad Safeda with 9 levels of N (0-800g/tree/year) and common doses of P2O5 and K2O (400g/tree/year, each). The highest tree volume was obtained at 300g N. The highest yield was also recorded at 300g while for 1991 as well as the average yield for 4 years; the maximum was at 600g. Fruit weight increased slightly while TSS, ascorbic acid, reducing sugar and pectin contents increased significantly upto 600g. The acidity of the juice significantly reduced due to N application. The results showed that for 5–6 year, old trees, 300g/tree/year and for 7–8 years old trees, 600g/tree/year was the optimum N dose to achieve high fruit yield and good fruit quality of guava.