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麦秆蝇在内蒙一年发生两代。以幼虫在禾本科宿根杂草中越冬,在中滩地区现己肯定的越冬寄主共有五种,而以披硷草(Clinelymus dahuricus(Turcz.)Nevski)中越冬虫口密度最大。翌年春越冬幼虫化蛹,越冬代成虫于5月下旬至6月初开始盛发,此时是开始药剂防治适期。盛发期的早晚与4月及5月份月平均气温具有强负相关,试以4月1日起至成虫开始盛发前一日止,日平均温度总和至760日度,预测越冬代成虫开始盛发,有相当的准确性。越冬代蛹期平均为15.33天。成虫羽化以上午6至8时最多。羽化后至开始产卵的历时平均为5.35天。每雌虫产卵量平均为11.8粒,最多41粒。产卵期间平均为11.1天,最长22天。越冬代雌成虫寿命平均为16.24天,雄虫为12.28天。越冬代成虫在麦苗上产卵,卵散产,大多产于麦叶正面近基部4毫米范围内。成虫对产卵地位具有明显的选择性,以第三及第四叶片上着卵最多,成虫喜产卵于具有4至6个叶片(拔节到孕穗期)尤其是拔节期的麦茎上。由于小麦生育期的不同,不仅着卵密度不同,幼虫入茎为害率也有差别,麦茎生育期愈近老熟,着卵愈少,幼虫入茎为害率愈低。第一代卵盛期在6月上、中旬,孵化盛期在6月中、下旬,至6月末己全部孵化。卵期平均为5天。幼虫孵化后从小麦叶基叶鞘与茎间蛀入为害。第一代幼虫于6月下旬后半期开始化蛹,化蛹盛期在7月上旬至7月中旬初期,7月中旬末基本上己全部化蛹,蛹期平均为9.9天。7月下旬为羽化盛期,麦收愈早,麦秆中遗留麦秆蝇蛹愈多,但内蒙西部地区大部分在7月下旬进行麦收,此时第一代成虫已大部羽化飞出,部分转向田间落粒自生麦苗上产卵,大部分第一代成虫转移到附近杂草、糜子、马铃薯、蔬菜或其他茂密的作物田中,除杂草外,未发现卵粒,仅系暂时潜藏处所。第一代成虫在越冬寄主上产卵,卵期平均为6.38天。幼虫孵化后入茎寄生生长发育直至越冬。
Two generations of straw flies occur in Inner Mongolia each year. Five species of overwintering host plants are now identified as positive in the perennial gramineous weeds, and the most overwintering population in Clinelymus dahuricus (Turcz.) Nevski. Spring over the next spring larvae pupation, overwintering on behalf of adults in late May to early June began Sheng, this time is the beginning of the appropriate agent control. The morning and evening of Shengfa period had a strong negative correlation with the monthly mean air temperature in April and May. The trial started from April 1 until the day before the adult started to bloom, and the average daily temperature summed to 760 days. Sheng hair, there is considerable accuracy. Overwintering pupal an average of 15.33 days. Adult feathers to 6 up to 6 am. The average duration after eclosion to start laying eggs was 5.35 days. The average fecundity of females is 11.8, with a maximum of 41. During laying an average of 11.1 days, the longest 22 days. Overwintering adult female adults average life of 16.24 days, male for 12.28 days. Overwintering generation of adults in the sprouts on the wheat seedlings, spawning, mostly produced in the wheat near the front of the base 4 mm range. The adults had obvious selectivity to the spawning position. The third and the fourth leaves had the most eggs, and the adult hippos lay on wheat stems with 4 to 6 leaves (from jointing to booting), especially jointing. Due to the different growth stages of wheat, not only the different egg density, larvae into the stem damage rate is also different, the more mature the wheat stem growth period, less eggs, larvae into the stem damage rate is lower. The first generation of egg peak in June, mid-incubation period in mid-June, late, to the end of June have all hatch. The average egg period is 5 days. After larvae hatch from the leaves of wheat leafhopper and stem borers harm. The first generation of larvae after late June half of pupation, pupation peak in the early to mid-July early July, mid-July end has substantially all of pupation, pupal stage an average of 9.9 days. In late July, the feathering period, the earlier the wheat harvest, the more wheat straw left in the flies pupae, but most of the Inner Mongolia region in late July wheat harvest, when the first generation of adults have been most of the emergence of feathers, some Turning to field sprouting Self-sprouting wheat sprouts spawn. Most of the first-generation adults migrate to nearby fields of weeds, millet, potatoes, vegetables or other dense crops. No weeds are found except for weeds, leaving only temporary shelter. The first generation of adults lay their eggs on wintering hosts, with an average egg age of 6.38 days. After larvae hatch into the stem parasitic growth until winter.