BIOCONVERSION OF PADDY STRAW AND BIOFERTILIZER FOR SUSTAINABLE RICE BASED CROPPING SYSTEMS

The recommended models was carried out on three different provinces of Mekong Delta viz., An Giang, Can Tho and Long An at different in 30 households to study the effects of composting paddy straw by Trichoderma sp combined with nitrogen fixing bacteria Gluconacetobacter diazotrophicus, Bradyrhizobium japonicum (for soybean) and Bradyrhizobium spp (for groundnut) and phosphate solubilizing bacteria (Pseudomonas syringae). Application of recommended models on rice – soybean/groundnut - rice enhanced yield components and grain yields of crops at three sites of different seasons excepting in Cantho site at 2007 Spring – Summer season as compared to conventional farmers’ fertilizer model. The average input of fertilizer cost for three crops in three seasons were saved at an amount of VND 953,640 / ha equal to 45.74 % as compared to farmers’ practice. In the recommended model, the gross input also got reduced VND 1,092,277 / ha equal to 14.48 %; rice, groundnut and soybean grain yield increased at 12.37 %, 19.71 % and 5.24 %; respectively. The total income increased as 12.28 %; the cost price were reduced to an extent of 27.94 %, 9.10 % for rice and leguminous crops, respectively led to the income increased to an amount of 2,773,586 VND/ha equal to 45.13 % as compared to farmers’ practice model. Furthermore, the quality of the products such as lipid, protein, phosphorus, potassium contents as well as soil available nutrients and benefit microorganisms (fungi, bacteria and actinomycetes) enhanced significantly at the harvesting stage. The total benefical microorganism population in soils of the recommended model increased 4.23*10 8 CFU/g dry soil, 3.39*10 8 CFU/g dry soil and 8.85* 10 8 CFU/g dry soil for An Giang, Can Tho and Long An, respectively in comparision to the conventional farmes practice model.