Studies On Biofumigation And Hot Water Treatment To Replace Methyl Bromide For Management Of Soilborne Plant Diseases

In vitro tests using cotton yarn jars as key equipment indicated that fumigation with the B. oleracealeaf at dosage 3.5kg/m2 for 6 days at 32oC could inhibit the colony growth of Fusarium oxysporuf.sp..cucumerinum,rulation and germination rate of the produced spores of F. oxysporu f.sp..cucumerinumby 83.1% and 8.4%, respectively, in comparison with those from non-fumigation treatment. Suppressivespectrum tests indicated that B. oleracea leaf at 3.5kg/m2 suppressed colony spread of F. oxysporumf.sp..cucumerinum, F. oxysporum f.sp..lycoersici, Rhizoctonia solani AG1, R..solani AG4, Verticilliumdahliae and Phytophthora boahmeriae by over 60%, and suppressed Sclerotinia sclertiorum, Pythiumaphanidermatum and Bipolaris sorokinianum by 38.7%, 17.4% and 41.6%, respectively. Tests on theeffects of various plant materials as biofumigantionsources demonstrated that B. juncea var multiceps, B.juncea and B. napobrassica were more effective than the B. oleracea in suppression against the tested 7pathogenic fungi. Comparison of different amendments indicated that wheat bran supplement (1.0kg/m2)and calcium carbonate supplement (100g/m2) couldenhance the biofumigation ofeffect, in contrast to thatby using B. oleracea leaf only. Tests indicated that biofumigation effect could be better over 32℃. Fieldtrials demonstrated that biofumigation with the 4 plant sources was more effective than solarization andreducing redox potential of soil, with up to 68.2% and 59.3% of control efficacy against tomato Fusariumwiltdiseaseandrootknotnematodesby B.junceaamendedwithwheatbran.Results onthe effects of hot water treatment of soil onroot knot nematodes indicated that populationof root knot nematode could be reduced by 81.1%. Tests on the soil microbial indicated that hot watertreatment resulted in significant change of soil microbial, from transplantingto pullingout the tomato, B/Fand A/ F obviously advances compared to the contrast. Field tests demonstrated that the relatively effectachieveduptomorethan60%inthetomatodifferentperiod.