【作者】 裴海英；

【导师】 赵奎军；

【作者基本信息】 东北农业大学 ， 农业昆虫与害虫防治， 2003， 硕士

【摘要】 在本论文中，对我省水稻新发生危害的钻蛀性害虫二化螟的生活史、生活习性、为害寄主、各虫期发育的有效积温进行了较为系统的研究，对不同虫口密度下的二化螟为害水稻所造成的产量损失进行了评估，并对二化螟的生物防治途径进行了探讨。 研究结果表明：二化螟在黑龙江省是以老熟幼虫在水稻、田茅、稗草等植物的茎杆、根茬中越冬，1年发生1代。越冬幼虫在5月下旬开始化蛹，化蛹盛期在6月上、中旬，化蛹时间一直可持续到6月下旬。蛹期平均10.9天。成虫羽化初期在6月初，盛期在6月中、下旬，7月初终现。成虫羽化至产卵历期平均5.5天。成虫期平均6.5天。成虫产卵始期在6月上旬，盛期在6月中旬末至下旬，产卵末期在7月初。卵期平均约7天。幼虫孵化初期在6月中旬，盛期在6月下旬至7月初，一直持续到7月中上旬。幼虫一直在水稻中为害，直到9月中、下旬大部分幼虫老熟，并在寄主的茎杆和根茬中越冬。 二化螟为害的作物种类较多，除了水稻外，小麦、玉米、谷子、高粱等禾本科作物均能造成为害，并形成典型的为害症状。二化螟成虫具有明显的趋光性。成虫产卵为块产，主要产在靠近叶鞘的叶片叶背基部，也有很多产在叶片正面近叶尖处。产卵时对植株具有选择性，喜在叶色浓绿、生长粗壮、高大、茂盛的稻株上产卵；产卵时对植物种类也有选择性，以水稻着卵量最大，其次为田茅、而在玉米、高粱、谷子、小麦、稗草上着卵量较少。初孵幼虫群集在水稻叶鞘为害，造成水稻“枯鞘”。幼虫2～3龄后分散到附近植株上并钻茎为害，常造成“枯心”、“枯孕穗”、“白穗”等典型被害状。幼虫耐水淹且有转株为害的习性。 二化螟越冬代蛹的发育起点温度为11.9±1.1℃，有效积温为121.8±1.8日·度；在不喂糖水的情况下，雌、雄成虫平均发育起点温度为18.5±0.9℃，有效积温为37.1±9.0日·度；卵的发育起点温度为14.2+2.5℃，有效积温为55.0±1.5日·度；而幼虫随着龄期不同，其发育起点温度和有效积温各不相同。1～5龄幼虫的发育起点温度和有效积温分别为15.7±1.4℃和45.3±2.3日·度；13.0±1.9℃和66.1±1.5日·度；10.1±0.5℃和84.3±2.8日·度；14.9±1.2℃和62.6±2.1日·度；17.0±3.4℃和73.3±0.9日·度。 苏云金杆菌的复配制剂菌剂1号对二化螟具有较好的致死效果，杀虫速度也较快，施药后24h、48h的校正死亡率分别达到78.1％和100％。 东北农业大学农学硕士学位论文一 不同虫口密度下的二化螟为害水稻，影响产量损失的主要因素是“枯心”和“白穗”，“虫伤株”对产量也有较大影响，在每穴有虫吕头、10头、14头、20头的情况下，水稻产量损失百分率分别达到33，39％、3466％、38．36％和50．64％。更多还原

【Abstract】 In this paper, the biology characteristics and life cycle of rice stem borer Chilo suppressalis (Walker) (Lepidoptera:Pyraridae ) in Heilongjiang province are systematicly studied. The host plants and thermal constants were also studied. The assessment of output loss was given in different density of rice stem borer,and the method of biological contol was inquired into at the same time.The research result shows: The rice stem borers lived as mature larvae in the stems and stubbles of rice and barnyard grass in winter in HeiLongjiang province, Chilo suppressalis occurred one generation each year. The overwintering larvae startled pupating in the last ten days of May, went to peak from the first ten-day to the middle ten-day of June, and get down the last ten-day of June. The average of pupal period was 10.9 d. The initial stage of the adult worm emergence was hi the beginning of June, the peak period was in the second and third ten days of June, ending in the beginning of July. The average time from adult worm emergence to oviposition was 5.5 d. The adult stage was about 6.5 d. The adult preoviposition was in the first ten days of June, and the peak period was from the end of middle ten days to the last ten days of June. The last oviposition stage was in the beginning of July, and the oviposition period was about 7d. The initial stage of hatching period was in the middle of June. The peak period was from the last of ten days of June to the first ten days of July. The larvae did not injure the rice until the majority of mature larvae in the stem and stubble in the middle and the last of September for overwintering.The host plants of rice stem borer were investigated. It was proved that the rice stem borer did harm to the grass such as rice,wheat,corn millet and Chinese sorghum and it showed the typical damaged symptom. The adults had obvious phototaxis.They mainly massive ovipositted in the back basilaminar of blades near the sheath, and the front of blades near the leaf apex. There was host selectivity when they ovipositted. They prefered to oviposit in the dark green, thick and exuberant plant. They ovipositted the most quantity at rice, more at corn, Chinese sorghum,millet and wheat, seldom at barnyard grass. The hatched larvae resembled together at the sheath and made it scorched. The larvae scattered to the other plants after 2 to 3 larval instar resulting in deathheart, deathbooting and wite stachys. The larvae were water-tolerant and heteroicous.The development lower thresholds and thermal constants were 11.9+1.1 and 121.8+ 1.8day-degrees(dd);18.5+0.9 and 37.1+0.9 dd;14.2+2.5 and 55.0+1.5 dd;15.7+1 and 45.3+2.3 dd;13.0+1.9 and 66.1+1.5 dd;10.1+0.5 and 84.3 +2.8 dd;14.9+1.2 and 62.6+2.1 dd;17.0+3.4 and 73.3+0.9 dd,for overwintering pupae, adults of male and female without feeding syrup, egg, 1st-5th larve instars, respectively.The mixture of Bt and biological pesticide took great effects on controlling the rice stem borer.The mortality were 78.1% and 100% after treating with the mixture 24h and 48h later respectively.The main factors for decreasing output were deathheart and wite stachys. The attacked plants had more effects to the output loss also. The output loss were 33.39%, 34.66%, 38.36% and 50.64% larvae per plant at 8, 10 , 14 and 20.Candidate: Pei Halving Speciality: Agricultural Entomology & pest controlSupervisor: Prof. Zhao Kuijun更多还原