ALLELOPATHIC POTENTIAL OF Silybum marianum L. AGAINST THE SEED GERMINATION OF EDIBLE LEGUMES

A laboratory based trial using water extract was conducted to investigate the allelopathic potential of Silybum marianum L. on kidneybean (Phaseolus vulgaris L.), mungbean (Vigna radiata L.), chickpea (Cicer arietinum L.) and soybean (Glycine max L.) during April 2011, in the Weed Science Research Laboratory, Department of Weed Science, Khyber Pakhtunkhwa Agricultural University Peshawar, Pakistan. Fresh plants of S. marianum were collected, dried and ground. Then the powder was soaked in tap water @ 55g/liter and 110g/liter. Ten seeds each of kidneybeans, mungbean, chickpea and soybean were placed in Petri dishes separately and different concentrations of extracts were applied according to the requirements. A control treatment (0 g/liter) was also included for comparison. The experiment was laid out in completely randomized design (CRD) with three replications and treatments. The results showed that with increasing the leaves extract concentration of S. marianum, a significant decrease was noted in the germination percentage, mean germination time (MGT), germination index (GI) and seed vigor index (SVI) of the test species. The tolerance order of the mungbean and soybean against the extract concentration of S. marianum was higher than the other two species, while the chickpea was more susceptible to the toxicity of S. marianum. Therefore, it was noted that the infestation of S. marianum can pollute the soil by accumulating toxic chemicals and affect the agro-biodiversity. Our findings suggest that preventing spread of S. marianum is the better weed management method in legume crops in order to avoid any post germination problem.