Impact of potassium fertilizer in growth and yield of some pea (Pisum sativum L.) varieties under Sulaymaniyah–Iraq conditions

This study was conducted to determine the effects of four potassium applications on five pea varieties for growth and yield components at Qlyasan Research Station, Faculty of Agriculture, University of Sulaimani during the winter season of 2014-2015 and spring season of 2015. Experiment was arranged using a factorial, split-plot design, within a randomized complete block design with three replicates, over two years. Potassium (0, 40, 60 and 80 kg K2O.ha-1) were assigned to main plots and cultivars Avolla, Joneor, Sancho, Green sage, Mamoth) to sub-plots. The effect of potassium fertilizer was significant for all growth characters except number of branches per plant. Root characters respond to potassium fertilizer significantly except the characters root length and nodules dry weight. Seed yield and all its components respond significantly to potassium applications. The growth characters plant high, number of leaves per plant and leaf width responds significantly to varieties effect. The root of fresh weight, number of nodules per plant and nodules dry weight were significant among cultivars. Regards to the second season, the effect of potassium fertilizer was significant in all studied characters except number of branches per plant, number of seeds per pod, biological weight per plant and harvest index. Potassium level of 80 kg K2O.ha-1 showed superior value for most of studied characters.