Effect of different sources of potassium on yield and quality of apple (cv. Red Delicious) in temperate conditions

Abstract

The present investigation was carried out to observe the effect of potassium on different parameters of apple in temperate conditions. Randomized block design experiment was adapted for an orchard of 15 years old with collection of soil samples and their analysis for physico-chemical properties under different treatments with fixed quantity of urea (1500g/tree), DAP (750g/tree) and potassium through MOP, K2SO4 and K-Schoenite (2500g/tree) in three, one and two split applications, respectively. The first application of recommended quantity of fertilizers was applied three weeks before expected bloom, Second three weeks after fruit set and third application at the end of July. Sample collection was done in the month of September followed by analysis for different parameters and results revealed that application of potassium through MOP @ 2500g/tree with two foliar applications of MOP @ 1.5 % including vermicompost @ 5kg/tree (T4) improved soil physical conditions, nutrient availability, fruit yield and quality of apple. The combined effect of chemical fertilizer, two sprays and organic fertilizer (vermicompost) showed significantly (P?0.05) higher results of nitrogen, phosphorous, potassium magnesium and sulphur but low calcium than other vermicompost added treatments. The work concluded that different potassium sources can have great impact on yield and quality of apple and respond to level of concentrations or dose as applied in current study with different split.