Effect of different levels of potassium on growth, yield and fruit quality of apple (Malus domestica Borkh)

A study was conducted to find out the effect of different levels of potassium on growth yield and fruit quality of apple cv. Starking Delicious. The treatment consisted of seven levels of potassium i.e. 400, 500, 600, 700, 800, 900 and 1000 g K2O tree−1year−1. All the trees received uniform dose of 700 g N tree−1year−1 as CAN and 350 g P2O5 tree−1year−1 as basal dose. Fruit yield increased up to 800 g K2O during the year 2007 and up to 700 g K2O during the year 2008 and the result was found to be significant. Maximum extension growth i.e. 23.6cm and 26.9cm was obtained with 700g K2O tree−1year−1, whereas non- significant difference was found in other growth characters at different levels of potassium. On total soluble solids and fruit firmness, application of potassium at different levels had significant effect. TSS content was found maximum at 1000g K2O tree−1 and fruit weight was maximum i.e. 156g with 700g and 157g with 800g K2O tree−1, respectively during 2007 and 2008.