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北京十字花科蔬菜上的蚜虫是桃蚜和菜缢管蚜,前者全年都有发生,而后者划在6月才开始发生。桃蚜以卵期在窖藏大白菜和核果类果树枝条上越冬,也有少数有翅成蚜能在窖藏大白菜上渡过参天。但白菜上的卵由于食用及留种株切关剥邦处理,而不能成为有效蚜源。另一部分桃蚜则在温室里连续发生,不进行越冬。阳畦菜苗和风障根茬菠菜上早春很早就发生桃蚜。大白菜留种株三月种植,它的第一蚜源来自风障根茬菠菜——3月下至4月初产生有翅蚜迁飞。桃树上的桃蚜在4月下开始发生有翅蚜,成为种株的第二蚜源。种株上的蚜群5月中产生有翅蚜,连续向外扩散。春菜——主要是甘蓝、花椰等——在定植时(四月)从阳畦带蚜下田;它的第二蚜源也来自桃树。春菜上的蚜群也在5月中产生有翅蚜扩散。从4、5、6月进行杂草调查证明,有9科13种是桃蚜的寄主,未发现菜缢管蚜的寄主,而旋花科的小旋花是唯一能在5月发生有翅蚜的杂草(6月没有)。由此可见,杂草不是春菜地的主要蚜源。桃蚜和菜缢管蚜在夏菜上——包括晚甘蓝、晚苤蓝、萝卜、小白菜、小油菜——混合发生,但有明显的偏嗜现象:桃蚜在甘蓝和苤蓝上占多数,菜缢管蚜在萝卜、白菜、油菜上占多数。从有翅蚜发生期看,甘蓝、苤蓝上的桃蚜正是秋白菜苗期的蚜源,同时萝卜、小白菜、小油菜上的菜缢管蚜也正是秋白菜苗期蚜源。秋白菜上也是两种蚜虫混合发生,但菜缢管蚜多于桃蚜,它们在9月上、中旬产生有翅蚜扩散。
Aphids on the cruciferous vegetables in Beijing are Myzus persicae and Aphis gossypii, the former occurring all year round, while the latter is scheduled to start in June. Myzus persicae oviparous period in the hoarding of Chinese cabbage and stone fruit trees branches overwintering, there are a few winged into aphids in cabbage over cabbage. However, the eggs on cabbage due to edible and plant-cut off Peibang treatment, and can not be an effective source of aphids. Another part of the green peach aphid occurred in a row, not overwintering. Barley aphid occurs on the spinach on the early spring and has a long history. The remaining Chinese cabbage plants planted in March, its first source of aphids from the windbreak of stubble spinach - from March until early April to produce a winged aphids migrate. The peach aphid on the peach tree began to have winged aphids in April and became the second aphid source for the species. Aphids on the strains produced a winged aphid in May and continued to spread outward. Spring vegetables - mainly cabbage, cacti and others - drop aphids from the sunnyside when planting (April); its second source comes from peaches. Aphids on spring vegetables also produce a winged aphid in May. Weed surveys from April, May and June showed that 9 families and 13 species were hosts of Myzus persicae and no host was found. However, the Convolvulaceae small cyclamen was the only one with winged Aphid weeds (not in June). Thus, weeds are not the main aphid source in spring. Myzus persicae and cabbage aphid occurred in the summer cabbage - including late cabbage, eveninggreen blue, radish, cabbage, rapeseed - occurred, but there is a clear preference for insects: Myzus persicae in cabbage and blue Most, aphid cabbage vegetables turnip, cabbage, rape majority. From the occurrence of winged aphids, the green peach aphid on cabbage and blueberry is the aphid source at the seedling stage of cabbage. At the same time, the cabbage aphid on radish, cabbage and small rapeseed is also the aphid source of the autumn cabbage seedling. Autumn cabbage is also a mixture of two kinds of aphids occurred, but aphid more than Myzus persicae, which in September, the middle of apiary aphid proliferation.