白菜黑斑病病菌孢子飞散及其传播定量研究初报

Preliminary quantitative studies on spore flying and spread of disease of cabbage black spot disease

以白菜[Brassica pekinensis(Lour.)Rupr.]品种为掰帮菜为试材,采用室内鉴定和田间试验相结合方法,对白菜黑斑病[Alternaria brassicae(Berk.)Sacc.]病菌孢子飞散和病害传播进行了初步研究。结果表明,白菜黑斑病病菌孢子多在白天飞散,在白天和夜间飞散释放的孢子数量之比为1.5～4.5∶1;病菌孢子飞散传播数量与高度的回归方程:y1=719.418 701 7exp(-0.065 545 79x1),(r=-0.928 6,P0.05=0.878 3),越接近地面孢子数量越多;在全田普遍发病条件下,得到顺风向一代传播距离的回归方程:y2=55.76-0.101 04x2,(r=-0.948 4,P0.01=0.536 8),传播距离5～6 m;逆风多代传播距离的回归方程:y3=707.275/x30.830 7,(r=-0.951 1,P0.01=0.917 2)。由此推算,在1个生长季节里其病菌孢子传播距离可达3 km。

Spores scattering and spread of cabbage black spot disease caused by Alternaria brassicae （Berk.） Sacc. were studied in laboratory and field. The results indicated that majority of the spores spread in the air during the daytime and the ratio during the day and the night was about 1.5N4.5：1. The regression equation of spores quantity （y1） and height （xl） was y1=719.418 701 7exp （-0.065 545 79x1）（r= -0.928 6, P0.05=0.878 3）, and the closer to the ground, the more spores there were. At condition of entire morbidity and downwind, the regression equation of spores quantity （y2） and height （x2） of one generation was y2 = 55.76-0.101 04x2 （r=-0.948 4, P0.01=0.536 8）, and the spread distance was 5-6 m, while at the condi- tion of dead wind, the regression equation of spores quantity （y3） and height （x3） of muhiple generations was y3= 707.275/ x3 0.8307 （r=-0.951 1, P0.01=0.917 2）, and spread distance of the spore can reached to 3 km in single growth season.