Effects of a Formulated Bio-product Containing the Nitrogen Fixing Bacterial Strain Enterobacter oryzae 3LSO1 on Sugarcane Growth

Abstract

Nitrogen (N) is an essential element for plant growth, widely applied as chemical N-fertilizer to improve yield of sugarcane. The elevated doses of fertilizers may have negative and unpredictable effects on the environment. Bio-fertilizers containing nitrogen fixing bacteria (NFB) are alternative and potential way to reduce application of chemical N-fertilizer. The NFB strain Enterobacter oryzae 3LSO1 isolated from rhizosphere soil of sugarcane can fix atmospheric dinitrogen (N2), produces indole-3-acetic acid as plant growth promoting substance. Therefore, this effective strain was developed as a vermiculite-based bio-product to enhance sugarcane growth. The bio-product was compared storing conditions at 10 and 30 °C for 30 or 60 days after formulation (DAF), and then its performance was evaluated. Result stated that the bio-product could be kept at 10 and 30 °C for up to 60 DAF without a decrease in the NFB population or a loss in its ability to fix N2. In a greenhouse experiment, commercial sugarcane variety Khon Kaen 3 applied with the E. oryzae 3LSO1 bio-product and planted with or without nitrogen fertilizer could increase the tiller number, plant height, fresh and dry weight, NFB population in soil and sugarcane, compared with the control. This E. oryzae 3LSO1 bio-product not only used as a bio-nitrogen fertilizer for sugarcane crops, but also reduced chemical N-fertilizer application for sustainable agriculture.