نتایج جستجو برای: ladybird hippodamia variegata goeze coleoptera coccinellidae has been reported from many parts of iran
تعداد نتایج: 21685463 فیلتر نتایج به سال:
the family of pteromalidae (hym: chalcidoidea) is one of the largest families of parasitic wasp. members of this family wasp comprise of important natural enemies of many harmful insects in major insect orders such as coleoptera, diptera, lepidoptera, hymenoptera and homoptera; therefore they have an important role in biological control of agricultural pests. the chalcid wasps belonging to this...
الگوی پراکنش جمعیت آفات در محیط یکی از عواملی است که نه تنها بر برنامه نمونه برداری و روش تجزیه و تحلیل داده ها مؤثر است، بلکه می تواند برای اندازه گیری تراکم آفت و دشمنان طبیعی آن ها نیز استفاده شود. بر همین اساس در طی دو فصل زراعی 1391 و 1392، پراکنش فضایی جمعیت شته نخود، (acyrthosiphon pisum harris (hem., aphididae، و دو شکارگر مهم آن در مزارع یونجه استان همدان، hippodamia variegata goeze co...
from 1950s onward, new theories and critical approaches burgeoned across humanities. these theories were context-oriented; as a result, the analysis of discursive practices gained significance. thus, social, political, historical and cultural discourses that have been hitherto marginalized and considered inferior to literary texts, were introduced as important texts to be analyzed by critics. o...
Studies of predation of ladybird beetles (Coccinellidae) have focused on a limited number of predator taxa, such as birds and ants, while other potential predators have received limited attention. I here consider amphibians as predators of ladybirds. Published amphibian gut analyses show that ladybirds are quite often eaten by frogs and toads (Anura), with recorded frequencies reaching up to 15...
نرخ شکارگری اساس هر پژوهش در برهم‌کنش شکار-شکارگر است و یکی از اجزای مهم در انتخاب شکارگران در کنترل بیولوژیک بهشمار میرود. نرخ شکارگری کفشدوزکHippodamia variegata (Goeze) با تغذیه از تراکمهای مختلف (20، 40، 60، 80 و 100) عدد از پورههای سن سوم شته پنبه Aphis gossypii Glover در شرایط آزمایشگاهی (1±25 درجه سلسیوس، رطوبت نسبی 5 ±65 درصد و دوره نوری 16 ساعت روشنایی و 8 ساعت تاریکی) بررسی شد. ...
abstract: in the paper of black and scholes (1973) a closed form solution for the price of a european option is derived . as extension to the black and scholes model with constant volatility, option pricing model with time varying volatility have been suggested within the frame work of generalized autoregressive conditional heteroskedasticity (garch) . these processes can explain a number of em...
the debate whether esp teachers need to have knowledge of the specialized field they are teaching has been an issue in the literature over the last two decades. the aim of conducting this study was to explore iranian learners’ and instructors’ beliefs and attitudes concerning the role of specialized knowledge in teaching esp classes. a seventeen item questionnaire was administered to 400 esp le...
peace and national security protection and ironic solving of international conflicts become the preliminary foundation of the united nations charter and had been considered as the main responsibilities of the security council, after world war ii and the establishment of united nations organization. therefore, the security council enables to analyze every kind of conflicts and challenges which ...
nowadays,tourism industry considered as one of the main sources of income of a country.unfortunately and despite of owning plenty of cultural historical and natural attractions, iran has not reached to a proper position in this field. besides, the historical cities of a country are considered as the income resource and national wealth of it. qazvin with a rich cultural precedent, have suitable ...
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