Evaluation of the potentiality of diverse weed species in mobilising soil bioavailable phosphorus

The present study was carried out to assess the inorganic phosphorus (P)- dynamics under the rhizosphere of 10 weed species belonging to 8 different families. A fractionation study revealed that sol-P and Ca₂-P were highest in M. denticulata L. and C. rotundus L. with 67.25 mg kg^-1 and 48.37 mg kg^-1, respectively (p<0.05) which could be attributed to high alkaline phosphatase activity in the rhizosphere. Out of the selected weed species, labile-P: nonlabile- P content was highest in M. denticulata L. (0.42) which is 38% higher than C. arvensis L. In terms of biomass and leaf P (%) C. didymus (L.) Sm. recoreded highest but, interestingly M. denticulata L. though had a higher sol-P but failed to translocate P-to the above and below-ground parts. Hence, M. denticulata L. being legume was an excellent mobilizer of non-labile P and can improve the available P for the subsequent crop.