Study of effects of different levels of Nitrogen and Potassium on yield and yield components of rain-fed Lentil

In order to study the effects of nitrogen and potassium fertilizers on yield and yield components of lentil under rain-fed conditions, an experiment was carried out in Agriculture Research Center of Ardabil, Iran in 2008. A factorial experiment based on a complete randomized block design with three replications was used. Nitrogen treatments included three levels (0, 25 and 50 kg.ha-1), potassium treatments included three levels (0, 30 and 60 kg.ha-1) and there were two cultivars (a local and a new cultivar named ILL180). Traits including plant height, number of branches/plant, number of filled pod/plant, pod number, seed number/plant, 100-seed weight and grain yield per unit area were measured. Analysis of variance showed that cultivars were not statistically significant regarding grain yield. Application of 50 kg N.ha-1 fertilizer significantly increased the number of secondary branches/plant, number of filled pod/plant, total number of pod, seed number/plant and seed yield. Maximum seed yield was achieved when 50 kg N.ha-1 fertilizer was applied. Potassium fertilizer had no significant effect on the above-mentioned traits.