Phosphate-solubilizing bacterial activity and their effect to rice growth in acid sulphate soil

摘要

Efficiency of P fertilization in acid sulphate soil for rice cultivation can be improved by phosphate solubilizing bacteria (PSB) application. This study aims was to observe the capability of PSB disolved P insoluble and their effects on rice growth in acid sulphate soils at different level of P-fertilizer. PSB isolates namely P17.4.1, P17.4.2, P21.4.1 were observed their ability to dissolve tricalcium phosphate, aluminum phosphate and rock phosphate in liquid pikovskaya medium. The three PSB isolates were also examined for their effects on rice growth at different level of P-fertilizer (without fertilizer, 30 kg.ha~(-1). 45 kg.ha~(-1) and 60 kg.ha~(-1) P_2O_5) in pot experiment. The result showed that PSB were observed able to dissolve tricalcium phosphate and rock phosphate but were unable to dissolve aluminium phosphate. The pot experiment, showed that application of PSB and their interaction with P-fertilizer is not significantly influenced rice plant growth. Rice plant height and shoot dry weight are significantly influenced by application of P-fertilizer. The average of plant height in application P-fertilizer 30 kg.ha~(-1), 45 kg.ha~(-1) and 60 kg.ha~(-1) P_2O_5 increased 4.19 cm; 3.63 cm and 3.39 cm respectively compared with control. The shoot dry weight given 60 kg.ha~(-1) P_2O_5 increased by 52.13%.