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各种自然条件下闭囊壳越夏试验结果表明:土壤中,地面和麦茬上,麦垛顶层和底层,室外自然条件下的闭囊壳在秋苗出土前相继变成空壳;室内自然条件下,种子中以及麦垛中层的闭囊壳在越夏季节期间,子囊原生质体结构发生畸变,失去形成子囊孢子的能力。上述各种环境中的闭囊壳先后于7月中旬至9月上旬失去生活力和传病能力,均不能越夏后成为小麦白粉病的初侵染源。在小麦播种时用做过上述各种处理的闭囊壳进行隔离接种试验,试验结果进一步证实了越夏试验结论的正确性。在房山区白粉病发生严重的张坊及十渡一带山区,通过对自生麦苗和小麦秋苗感染白粉病情况的野外调查发现:海拔140m以上山区自生麦苗上的分生孢子是北京地区小麦白粉病在秋苗上的主要侵染源之一。
The result of the summer experiment of the closed shell under various natural conditions showed that the closed shell under the outdoor and natural conditions in the soil, on the ground and on the stubble, on the top and bottom of the stack, became the shell in succession before the autumn seedling was unearthed. The indoor natural conditions In the summer, the protoplast structure of the ascus was distorted, losing the ability to form ascospores. The above closed shell in various environments lost their viability and disease-transmitting ability from mid-July to early September and could not become the primary source of infection of wheat powdery mildew later in summer. Vaccination test was carried out in the closed shell of the shells that had been treated by the above treatments when the wheat was sown. The test results further confirm the correctness of the conclusion of the summer experiment. In Fangshan area, the serious occurrence of powdery mildew in the area of Zhangfang and Shidu was investigated by field investigation on the occurrence of powdery mildew in the wheat seedlings and wheat autumn seedlings. The results showed that the conidia on the wheat seedlings in the mountain area above 140 m altitude were wheat powdery mildew One of the main sources of infection on autumn seedlings.