استجابة نمو ومحصول الشعير (صنف الريحان )لطريقة الزراعة ومعدل البذار والسماد النيتروجيني تحت الظروف المطرية

Abstract

Two field experiments were carried out at the experimental Farm Agronomy Dept. Faculty of Agriculture, Omar Al-Mukhtar University, Libya during 2006/2007 and 2007/ 2008 seasons to study the effect of two sowing methods) drilling and broadcasting), four nitrogen levels (0, 50, 100 and 150 kg N/ha) and three seeding rates (50, 100 and 150 kg grains/ha) on growth and yield and quality of two-row barley (cv. Rehan). A split-split-plot design with four replications was used. The obtained results could be summarized as follows: 1. Sowing methods had a significant effect on plant height (1st season), number of tillers and spikes/m2, number of grains/spike, 1000-grain weight, straw yield, grain yield and harvest index in both seasons. While, date of 50% heading and protein content in grains did not significantly affected by sowing methods. 2. Increasing N levels up to 150 kg N/ha caused an obvious increase in plant height, number of tillers and spikes/m2, number of grains/spike, straw yield and grain yield per hectare and decreased 1000-grain weight and date of 50% heading as compared with control. Moreover, grain yield response per kg of N was calculated as 2.8, 3.0 and 5.2 kg of grains for the rate of 50, 100 and 150 kg N/ha, respectively. 3. The highest seeding rate of 150 kg grains/ha caused significant increases regarding number of tillers and spike/m2, 1000-grain weight and straw and grain yields per hectare in both seasons. On the contrary, this increase in seeding rate delayed time of 50% heading, spike length, number and weight of grain/spike. 4. Maximum straw yield and its related traits were recorded in 150 kg grains combined with 50 kg N/ha under drilling or broadcasting method, while the highest grain yield/ha was recorded in 100 kg grains + 150 kg N/ha under drilling as well as 150 kg grains and 150 kg N/ha under broadcasting method.