Effect of crop sequence and weed control treatments on weeds and pea crop productivity

摘要

Field experiment was carried out at Shandaweel Agriculture Research Station during 2012/2013 and 2013/2014 winter seasons to study the effect of 24 treatments which were the combinations in spilt plot design where four crop sequences (Wheat/sorghum, Wheat/peanut, clover/sorghum and clover/peanut) were laid main plots and six weed control treatments (Gesagard at 1.0 L/fed, Sencor at 300 g/fed + Select super at 500 cm 3 /fed, Basagran at 500 cm 3 /fed + Select super, Gesagard + Select super, hand hoeing twice at 20 and 45 days after sowing (DAS) and unweeded treatment (check) in split plot design on pea yield and associated weeds). Results revealed that crop sequence decreased significantly numbers (m 2 ) and dry weight of grassy, broad-leaved and total weeds (g/m 2 ) in both seasons. Sowing pea after clover/sorghum and clover/peanut decreased the numbers (m 2 ) and dry weight of weeds (g/m 2 ) and increased significant plant height, number of branches/plant, pod length, pod width, number of ovules/pod, shell-out %, 100-green seed weight, green pod yield (ton/fed) and dry seeds yield (kg/fed) as compared with sowing of pea after wheat/sorghum or wheat/peanut in both seasons. Crop sequences significantly affected each of vegetative growth, yield and its components in both seasons. Weed control treatments decreased significantly the numbers and dry weight of grassy, broad-leaved and total weeds (g/m 2 ) in both seasons. Application of hand hoeing at 20, 45 DAS, Gesagard at 1.0 L/fed + Select super and Basagran at 500 cm 3 /fed + Select super at 500 cm 3 /fed gave the highest reduction of the dry weight of grassy, board-leaved and total weeds (g/m 2 ) in both seasons. Hand hoeing at 20, 45 DAS, Gesagard + Select super and Basagran + Select super increased significantly the plant height, number of branches/plant, pod length, pod width, number of ovules/pod, shell-out %, 100-green seed weight (g), green pod yield (ton/fed) and dry seed yield (kg/fed). The effect of interactions between crop sequence and weed control treatments was statistically significant where decreased significantly the numbers (m 2 ) and dry weight of grassy, broad-leaved and total weeds (g/m 2 ) using of sowing of pea after clover/sorghum and clover/peanut under hand hoeing twice and Gesagard + Select super per in ceased than other treatments. The interactions between crop sequence and weed control treatments increased the number of branches/plant, 100-green seed weight (g) and green pod yield (ton/fed) under sowing of pea after clover/sorghum and clover/peanut and using of hand hoeing twice and Gesagard + Select super in both seasons. Correlation analysis was positive and significant in number and weight of grassy, broad-leaved and total weeds in both seasons. Increase in the numbers of all weeds species increased the dry weight of all weeds. 100-green-seed weight (g) and both green pod yield (ton/fed) and dry seed yield (kg/fed) were significantly negatively correlated with number and weight of grassy, broad-leaved and total weeds. On the other hand there is a significantly positive correlation between 100-green-seed weight and both green pod yield (ton/fed) and dry seed yield (kg/fed) in both seasons.