Factors influencing seed germination of wild onion and chickpea cultivars

Wild onion (asphodelus tenuifolius cav.) is a major weed of chickpea in the sandy tract of pakistan and elsewhere in the world,but its biology and physiology is less understood. seeds of its four biotypes were collected from bannu,karak,bhakkar and mianwali districts of pakistan for a series of laboratory experiments. seeds were treated with a range of concentrations of gibberellic acid,potassium nitrate,thiourea or sodium azide and incubated at three temperatures 10,20 and 30°c. the experiment was repeated once and was laid out in completely randomized design with factorial arrangement. biotypes differed in dormancy status. seeds of mianwali biotype had the highest germination (74.5%) while bhakkar (44.8%) and karak (44.6%) biotypes produced lower germination at 10 and 20°c. very little germination occurred at 30°c. in the second experiment the tolerance of five chickpea cultivars to sodium azide was probed by treating their seeds with sodium azide at 0,0.76,1.53,2.30 and 3.07 mm for comparison. all chickpea cultivars showed 100% germination at all concentrations except 3.07 mm where the two cultivars kk-1 and kc-98 had 95% germination. while a.tenuifolius produced very little or no germination at all concentrations except 0 and 0.76 mm. thus,to minimize the competition of wild onion in chickpea,sodium azide could be selectively applied to inhibit germination of wild onion in chickpea.