Effects of Phosphate Solubilizing Fungi on Growth and Yield of Haricot Bean (Phaseolus vulgarisL.) Plants

Abstract

Haricot bean (Phaseolus vulgarisL.) is one of the most important cash crops and export commodities besides its use in human food and soil fertility improvement. Phosphorus (P) is one of the major bio-elements that limits agricultural production. However, phosphate-solubilizing fungi play a noteworthy role in increasing the bioavailability of soil phosphates for plants. The purpose of this study was to evaluate the effects phosphate solubilizing fungi on the growth of haricot bean plants. Cultural and morphological features were used to tentatively identify the fungal isolates to genus level. Based In vitrophosphate solubilization efficieny conducted in both solid and liquid PVK medium following standard procedures, two best isolates were selected and evaluated under greenhouse for their performance on haricot bean. Under greenhouse experiment, shoot height (47.31 cm plant -1 ), root length (41.01 cm plant -1 ), nodule number (65.67 plant -1 ), nodule dry weight (0.59 g plant -1 ), shoot fresh weight (62.73 g plant -1 ), shoot dry weight (14.33 g plant -1 ), number of pod (12.89 plant -1 ), 50-seed weight (35.89 g plant -1 ), P content (0.59%) and N content (1.96%) were significantly increased by co-inoculation of two isolates (PSFAP) in the soil amended with rock phosphate (RP) compared to control. Moreover, the highest number of leaves (59.55 leaves plant -1 ) and root fresh weight (14.19 g plant -1 ) were recorded as a result of inoculation with isolate PSFP compared to control. The present study indicated the presence of potential plant associatedfungi that possess phytobeneficial traits for extending their use as microbial biofertilizers after testing their suitability for the desired purpose.