the effect of weed competition on germination indices and seed vigor of chickpea

abstract- this experiment was carried out during the growing seasons of 2010 and 2011 at the agricultural research farm of bu-ali sina university, to study the effect of weed competition on subsequent germination and seed vigour of chickpea. 12 weed interference durations were evaluated in a randomized complete block design with three replications. experiments consisted of two sets of treatments. in the first set, the crop was kept weed-free until 0, 14, 28, 42, 56 and 70 days after sowing and in the second set, weeds were permitted to grow within the crop until 0, 14, 28, 42, 56 and 70 days after sowing. results of the two year experiments showed that the traits germination index, germination rate, mean germination time, percentage of germination, abnormal seedling percentage and seedling dry weight were affected by different duration of weed interference. thereafter, the maximum value of germination rate and the minimum value of mean germination time belonged to the full weed-free condition. the increasing length of weed competition decreased seedling dry weight and increased abnormal seedling percentage. this finding is supported by a reduction in the seed weight. in other words, a decrease in seed storage contents resulted in a decrease in seedling growth and an increase in the percentage of abnormal seedlings.