نوع مقاله : گزارش کوتاه
نویسنده
عضو هیئت علمی موسسه تحقیقات گیاهپزشکی، تهران، ایران
چکیده
کلیدواژهها
عنوان مقاله [English]
نویسنده [English]
Since 1992, Population density of sugar beet root aphid has increased in Karadj, Shahriar, and savdjbolagh areas, and collected aphids were recognized by Rezwani (Ali), member of scientific board of Plant Pests and Diseases Institute.
In summer, patches of stunted and wilted plants of sugar beet observed in the field. When the plants are dug up, a large number of whitish aphids and their wax, are noticed on the fibrous roots. In suitable conditions the aphid population usually increase rapidly.
The summer form of this aphid that infest the roots is wingless, and is 2-3 mm long when fullygrown. The are pale yellowish white and are dusted with a white powder. The winter is spent in adult stage in the soil or probably in the egg stage on poplar trees, from where winged forms fly to the beet crops at the end of the spring. They give birth to wingless young aphids that infest the roots. In the autumn most winged forms fly back to the first host to lay their eggs but some remain in the soil and can infest beet crop grown there early the following year.
The aphids excrete a mass of white waxy material making the roots and aphid colonies appear to be covered with a white mould. Infested plants are stunted and wilted, that can even be killed by this aphid. Severe damage can be caused, especially when the beet crop is also suffering from drought.
کلیدواژهها [English]
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