寒地春油菜菌核病发生规律研究

研究结果表明,在黑龙江西北部春油莱菌核病于6月中旬始见病菌子囊盘,子囊盘数量与3 d内大气平均相对湿度呈正相关(R=0.657),与3 d内平均气温呈负相关(R=-0.604)。6月中旬始见大气中病菌孢子,7月中下旬出现高峰期。油菜花朵于6月下旬开始发病,7月上旬出现发病高峰期。花朵带病率与3 d内的相对湿度和日照时数显著相关(R₁=0.95;R₂=-0.857)。7月初叶片开始发病,7月中旬达到高峰期,以后逐渐下降。7月上旬茎秆开始发病,为土表菌核直接侵染造成,发病率低,增长慢;7月下旬因为病叶上病菌再侵染病害快速增长。

Studies on occurrence of Sclerotiorum disease on spring rape

The results of the study showed that the apothecium of the pathogen occurred in the middle of June. The number of the apothecium was correlative to the relative humidity ( R = 0. 675) and the average air temperature ( R = - 0. 604) of the last three days. The spore in the air appeared in the middle of June, and its fastigium appeared in the middle and last ten days of July. The flower was firstly infected in the last ten days of June. The fastigium of the infected flower appeared in the first ten days of July. The number of the infected flowers was correlative to the relative humidity ( R = 0. 95) and the hours of sunlight (R = -0.875) of the last three days. The leaves were infected in the early days of July, and its fastigium appeared in the middle ten days of July. The stems were infected directively by sclerotia in soil in the first ten days of July, but the number was very low and increased quite slowly. It increased very fast in the last ten days of July until the rape was reaped.