Effects of sowing rate on growth and protein contents of wall barley (Hordeum murinum L.) grown under Mediterranean conditions

Abstract

Accurate control of the seeding rate favours the establishment of a high-quality stand. Improper seeding rates waste seed and reduce potential yield. Our objective for this research is to determine the proper sowing rate for wall barley (Hordeum murinum L.) to obtain optimum and sustainable forage and seed yield in the northeastern depleted rangelands of Jordan. Wall barley seeding rates of 10kg ha^-1, 20kg ha^-1, 30kg ha^-1 and 40kg ha^-1 were evaluated in field studies that were conducted for two years at Ramtha Agricultural Research Station (32°33'N 36°0'E) located 22km to the east of Irbid. Measurements recorded each year included plant height, number of tillers per plant, oven-dry forage weight, seed yield and protein content. Forage and seed production increased in response to increasing sowing rate, and was highest at a sowing rate of 30kg ha^-1. Tiller numbers showed a negative response to increasing sowing rate. Plant height and crude protein content did not respond to seeding rate, but they varied with years (P ≤ 0.05). Protein content did not respond to seeding rates. The highest forage and seed yield of wall barley was obtained at 30kg ha^-1 seeding rate.