Phytotoxic effects of aqueous leaf extract of Senna alata on seed germination and biochemical changes in Vigna radiata L.

The phytotoxicity property of aqueous leaf extract of an invasive plant Senna alata L. on germinating seeds of green gram Vigna radiata was evaluated using ANOVA and found to be significant at 0.05% level. The reduced 'against concentration gradient' and phyto-toxicity index of the extract showed increasing trend; and both factors indicate concentration dependent activity. The stress enzymes amylase and invertase showed decreasing trend, whereas protease showed an increasing trend with coefficient of determination (r 2 ) values of 0.88, 0.95 and 0.94 confirming phytotoxicity of extract on germinating seeds of Vigna radiata as highly significant. Estimation of anti-oxidative stress by extract treated germinating seeds showed increasing H 2 O 2 production, SOD activity and FRAP activity. The experimental study demonstrated that the invasive plant Senna alata possesses phytotoxic properties which may be instrumental in weed management through lab-to-land programme. The study also showed that the increased enzyme activity can inhibit the seedling growth and therefore, could be used to suppress the growth of different weeds in crop fields.