Effect of foliar application of potassium and its spray schedule on yield and yield parameters of sweet orange (Citrus sinensis Osbeck) cv. Jaffa

Abstract

An investigation to evaluate the effect of foliar application of potassium and its spray schedule on yield and yield parameters in sweet orange cv. Jaffa was undertaken at experimental orchard, Department of Horticulture, CCS Haryana Agricultural University, Hisar during the year 2014-15. The results revealed that the foliar application of potassium nitrate at the rate of 2 and 4 % and potassium sulphate at 1.5 and 3.0 % significantly improved average fruit weight, fruit diameter, percentage of medium and large fruits, and fruit yield of sweet orange cv. Jaffa over control (water spray). The trend was vice-versa on the percentage of small fruits. The number of fruits per plant could not differ significantly due to various treatments. Among K sources and doses, foliar application of KNO3 at 4 % exhibited superiority over other treatments with respect to yield and yield parameters followed by KNO3 at lower dose (2 %) or K2SO4 at higher dose (3 %). Among various spray schedules, application of three sprays of K in the last week of April, May and August were found superior or at par in improving yield and yield parameters with 2 sprays in the last week of April and August. The fruit yield was recorded the highest (76.90 kg/plant) with a combination of the foliar application of KNO3 at 4 % and 2 sprays in the last week of April and August which was non-significant with KNO3 with an additional spray in the last week of May. The findings signify the importance of K spray in improving yield and yield parameters of sweet orange under semi-arid climatic conditions of north western India.