Effect of the emergence time of the weed Raphanus raphanistrumon bean growth in two planting seasons

Common beanis seriously affected by weeds interference, which can vary according to the weed's emergence time and the crop's planting season. This study aimed to evaluate the effects of relative times of Raphanus raphanistrumemergence on white beans in winter and summer season. An experiment was carried out for each season in 1.2 m x 1.2 m beds using a randomized block design, with Raphanus raphanistrumemergence times of 0, 10, 20, 30, 40, and 50 days after bean emergence (DABE) and a control without the weed, in four replications. Height, numberof leaflets, chlorophyll content, leaf area and dry matter of stems, leaflets, and fruit were determined in the crop. Also, weight of grains and pods per plant, weight of 100 grains and yield at harvest. Furthermore, dry matter of Raphanus raphanistrum's stems, leaflets, and fruit was determined. The data was subjected to analysis of variance using the F test, and means were compared using Tukey test at 5 % probability level. The lowest values for bean grain weight(152.72 g plant-1) and pod weight(223.67g plant-1) in winter season were recorded when Raphanus raphanistrumemerged at 10 DABE. The summer season showed the lowest bean grain and pod weightvalues (81.45 and 121.5 g plant-1, respectively) when Raphanus raphanistrumemerged simultaneously with the crop. Raphanus raphanistrumemergence time altered its interference with beans. Moreover, planting season influenced crop and weed development, thus varying the effects of weed's relative time of emergence on the crop.