Influence of Tillage, Crop Establishment and Weed Management Methods on Rhizosphere Micro Flora on Rice-Rice-Pulse Based Conservation Agriculture System

Field experiments were carried out in wetland farm at Tamil Nadu Agricultural University, Coimbatore, Tamil Nadu during kharif 2012, rabi 2012–13 and kharif 2013 to study the tillage, crop establishment and weed management methods Influence on soil micro flora of rice rhizosphere in rice under ricerice-pulses based conservation agriculture system. The treatments consist of six tillage methods viz., T1 - Transplanted rice with conventional tillage - conventional tillage - zero tillage, T2 -Transplanted rice with conventional tillage- zero tillage system- zerotillage, T3 -Transplanted rice with zero tillage + crop residue -zero tillage + crop residue - zero tillage, T4 - Direct sown rice with conventional tillage conventional tillage -zerotillage, T5 - Direct sown rice with conventional tillage -zero tillage system - zero tillage and T6- Direct sown rice with zero tillage + crop residue - zero tillage + crop residue -zero tillage as horizontal strips and three weed management practices as vertical strips viz., W1-Recommended herbicides (Transplanted rice - PE of Butachlor 1.0 kg/ha for kharif, PE of Pretilachlor 1.0 kg/ha for rabi and direct seeded rice - PE of Pretilachlor (S) 0.45 kg/ha), W2- Integrated weed management (Transplanted rice - PE of Butachlor 1.0 kg/ha for kharif, PE of Pretilachlor 1.0 kg/ha for rabi and direct seeded rice -PE of Pretilachlor (S) 0.45 kg/ha + inter crop with dhaincha and incorporated in 35 to 40 DAS through mechanical weeding) and W3 - Unweeded check. Significantly higher microbial population recorded in zero tillage + crop residue – zero tillage + crop residue – zero tillage system. Among the weed management practices integrated weed management recorded higher total bacterial, fungal and actinomycetes population.