番茄叶霉病重要流行环节初步研究Ⅱ.病斑产孢、孢子飞散

对番茄叶霉病病斑产孢规律的研究表明:在保湿24h内,随着保湿时间的延长,病斑相对产孢量也随之增加;黑暗条件有利于病斑产孢;病斑产孢适宜温度为10～28℃。其中,在23℃时产孢量最大,4℃和35℃时病斑几乎不产孢;在80%～100%的相对湿度范围内病斑均可产孢,病斑产孢量随湿度的增加而增大;另外,病斑相对产孢量随氮肥使用量的增加而增加,却随着磷钾肥使用量的增加而减少;6～9龄的病斑产孢能力最强。叶霉病菌分生孢子主要在夜间飞散;在番茄植株株高30～100cm范围内,60cm株高处分生孢子数量最多。

Preliminary Studies on Key Epidemic Links of Tomato Leaf Mould Caused by Fulvia fulva Ⅱ. Lesion Sporulation,Spore Dispersion

The regularity of lesion sporulation of Fulvia fulva(Cooke)Ciferri wasstudied. The results demonstrated that the quantity of lesion sporulation increased with　the prolonging of humidity keeping time  in 24 h. Lesions sporulated more in dark than in light. The suitable temperature for lesion sporulation was 10—28℃ and 23℃ was the optimal temperature. Lesions hardly sporulated at 4℃ and 35℃. Lesions could sporulate under the relative humidity of 80％ to 100％, and the quantity of sporulation increased with the  going up of humidity. The capacity of lesion sporulation had a significant positive correlation with the application of nitrogen fertilizer and negative correlation with phosphate or potassium fertilizer. Six to nine day lesions had the highest sporulation capacity compared with other age ones. Spores mainly dispersed at night. The highest quantity of spores was found at 60　cm parts within the tomato plant from 30 cm to 100 cm.