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杨树叶锈病在苗期及幼林期普遍发生。据我们到克山地区小叶杨纯林和小叶杨与落叶松混交林的调查,发病情况差异很大,其感病指数:前者为81.1;后者为45.9。而没有引种落叶松的地方,杨树叶锈病则不发生。多年在哈尔滨定点观察,落叶松叶片上于6月产生锈孢子堆,锈孢子出现一周之后,中东杨,小青杨,小叶杨及哈青杨等陆
Poplar leaf rust occurs in seedling and young forest. According to our investigation of the pure Populus simonii and mixed forest of Populus simonii and Larix gmelinii in Kushan region, the incidence of the disease varied greatly. The index of the disease was 81.1 for the former and 45.9 for the latter. Without the introduction of larch, poplar leaf rust does not occur. After many years of observation in Harbin, rusty spores were produced on the leaves of the larches in June. After one week of emergence of the rust spores, the populations of the Middle Eastern poplars, Populus simonii, Populus simonii, and Populus euphratica