نوع مقاله : مقاله پژوهشی
نویسندگان
1 مرکز تحقیقات کشاورزی و منابع طبیعی استان گیلان، رشت
2 دانشگاه آزاد اسلامی واحد لاهیجان
3 دانشگاه آزاد اسلامی واحد علوم و تحقیقات، تهران
چکیده
کلیدواژهها
عنوان مقاله [English]
نویسندگان [English]
Beech is one of the most important tree species in northern forest’s of Iran which is constanly subject to attack by biological and environmental factors. Cryptoccocus fagi Barspar (Hom.:Coccidae) is one of the major pests that directly or indirectly threatens beech stands. This insect was first reported in 1880 and in 1976 from Germany and Iran respectively . Insect length is 0.8 mm and It’s color is dark yellow .
This research was carried out in 851 ha. of Shenrood forest in Siyahkal region in the east of Guilan province. The main purpose of the studying to investigate population density of this pest on Beech trees as well as effects of environmental factors.
In this study , Beech trees were selected systematic randomly with lattice in 200×250 m dimensions.
Results of data analyzes of variance showed that :
a) This pest infested beech trees in lower sections of tree trunks.
b) about 23% of beech trees were infested by C. fagi.
c) There was a positive correlation between pest abundance and tree diameter .
d) A negative correlation was found between infestation rate and forest altitude.
e) In northern slopes, pest abundance was higher compare to the southern slopes and other sunlit areas.
f) The most sever infestation were observed on northern parts of tree trunks.
According to the results obtained we can say that light and moisture have a major role on abundance of this pest. There fore sound sylvicultural practices based on modern forestry science is one of the most important methods for control of this pest .Mean while identification and protection of natural enemies play an important role in alleviating of the pest damages .
کلیدواژهها [English]
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