Mehta, H. M.Patel, A. G.2018-04-172018-04-171988http://krishikosh.egranth.ac.in/handle/1/5810043776The field investigation was carried out at College Agronomy Farm, B. A. College of Agriculture, Anand Campus, Anand during kharif season of 1987 with a view to study the effect of soil solarization, summer ploughing and herbicide on weed control in rice (Oryza sativa cv. GR-11) nursery in Split Split Plot Design with three.replications. In the experiment, soil solarization and summer ploughing were carried out on 1 April, 1 May, 1 June and just before sowing i.e. 1 July (farmers method). The treatments were integrated with butachlor 1.5 kg/ha and 0.75 kg/ha applied 5 days before sowing as pre-planting spray. Hand weeding and unweeded control were also included in this experiment for the purpose of comparison. The results revealed that count and green weight of Digitaria sanguinalis was reduced conspicuously by cultural operation in May but had no appearent effect on Cyperua rotundus. Soil solarization and 1.5 kg/ha butachlor had reduced the count and green weight of Digitaria sanguinalis and Cyperus rotundus. however, interaction of solarization and hand weeding was most effective in reducing the count and green weight of both the weeds. Soil solarization in April had reduced the count and dry weight of total weeds, however hand weeding and 1.5 kg/ha butachlor effectively reduced the count and dry weight of weeds. The combination of soil solarization and hand weeding gave the highest reduction in dry weight of weeds. Time of soil solarization or summer ploughing had no apparent effect on count of total and healthy seedlings. Significantly higher, both the groups, seedlings were obtained from hand weeding and 0.75 kg/ha butachlor, however, the highest count was obtained from interaction of soil solarization and hand weeding. The dry weight of total seedlings and green weight of healthy seedlings was found to be increased by cultural operations in April, however, soil solarization found better as compared to summer ploughing. The highest dry weight of total seedlings was obtained from hand weeding and 0.75 kg/ha butachlor respectively. The highest profit (13657 Rs/ha) was obtained from the treatment of no solarization and 0.75 kg/ha butachlor combination. Soil solarization was conducive for weed control but the profit was not gained because of high cost of plastic film. Cultural operations in May and June reduced N, P2O5 and K20 content of weeds. Hand weeding had also reduced the N and P2O5 content of weeds but K2O content was not affected. The highest N, P2O5 and K2O content of rice seedlings was found in April soil solarization followed by hand weeding during crop growth period. Soil solarization and hand weeding increased the nitrogen status of soil.enAGRONOMY, AGRICULTUREA STUDYThesis