Effectiveness of Enterobacter cloacae to Promote the Growth and Increase the Yield of Rice

Abstract

Rice productivity in Indonesia is relatively lower than the rice productivities in other rice growing countries. In order to increase the rice productivity, it is necessary to find agents that can improve and promote the rice growth. This study was done to determine potential use of Enterobacter cloacae isolated from rhizospheres of Imperata cylindrica to promote the growth and increase the yield of rice under green house experiment. Five isolates of E. cloacae namely Al2N, Al3Bt, Al9Sa, Al6G, Al7Kla were tested for their effectiveness to promote the growth and increase the yield of rice. Treatments with isolates of E. cloacae significantly improved the growth of rice seedlings, in which the plant height, root length and number of root significantly (p<0.05) higher on treated plants when compared to control. These treatments were also significantly increased the number of tillers, content of chlorophyll in the leaf, content of macro nutrients in the leaf, the dry weight of shoot and the dry weight of root, but did not significantly (p>0.05) affect the plant height. Number of panicles per hill and percentage of filled grain per hill of treated plants were significantly higher than that of control, but the weight of 1000 grains did not significantly different. Rizhobacteria treatment increased the rice yield ranged from 22.53% to 26.13% when compared to control. No significant different were observed on all parameters among treatments with isolates of E. cloacae suggested that all isolates resulted in similar level of effect to the growth and yield of rice.  These isolates may be further developed as plant growth promoting agents to increase the yield of rice in Indonesia.

Keywords :  Enterobacter cloacae, plant growth promoting rhizobacteria, rice yield.