A study of the application of HA in the presence of biofertilizer along with P to see if the P use efficiency can be improved

Abstract

Optimization of phosphorus (P) fertilizer for mungbean (Vigna radiata) was studied during kharif 2012 
through integrated use of humic acid (HA), chemical fertilizers and biofertilizer viz., plant growth 
promoting rhizobacteria (PGPR) at NARC. The plots were arranged in split-split design under three factors 
(HA, P levels and PGPR inoculation). Results indicated that application of HA at 50 kg ha-1 along with 45 kg 
ha-1 P2O5 (75% P) in presence of PGPR inoculation recorded the highest grain yield (1.96 t ha-1 ) that is 19% 
more than the treatment receiving 100% P application alone (no HA and PGPR). The highest concentration 
of P (0.3 %) and N (3.5%) in whole shoot mung bean were observed in the treatment where HA was applied 
at 50 kg ha-1 along with 60 kg ha-1 P2O5 (100% P) and PGPR inoculation. However mungbean yield and P 
concentration was statistically at par with the treatment where P was applied at 75% of recommended rate 
along with H.A and PGPR. Based on findings of this study it can be suggested that HA and PGPR 
inoculation have significant effect on grain yield and improved P use efficiency (PUE). It showed that HA 
and PGRP enhanced P availability through chelation and reduce soil P fixation.