Allelopathic influence of Azadirachta indica leaf, stem and bark extracts on physiological responses of Phaseolus vulgaris L.

In the present investigation an attempt has been made to assess the allelopathic efficacy of neem leaf, stem and bark extracts on physiological parameters of bean seedlings. The aqueous leaf, stem and bark extract of neem showed inhibitory and stimulatory effects on protein, carbohydrate, chlorophyll and phenol content. The chl. a, b, total chlorophyll and carotenoid content were found to be decreased as the concentrations of the extract increased when compared to control except in 5% concentration. The total carbohydrate content in root shoot axis decreased as the concentration of the extract increased except in 5% concentration on the other hand in cotyledon increased compared to control. Total phenol and protein content in root shoot axis decreased as the concentration increased except in 5% concentration when compared to control on the other hand in endosperm it was found to be increased as the concentration of the extracts increased. The results of current study showed that both negative and positive effect of neem aqueous leaf, stem and bark extract may be due to the presence of allelochemicals.