棉铃虫卵和龟纹瓢虫、中华草蛉分布格局的关系研究

通过田间调查,研究了棉铃虫卵和龟纹瓢虫、中华草蛉空间分布的关系。研究表明,棉铃虫卵和龟纹瓢虫、中华草蛉在棉株垂直各层上的数量间相关系数6月分别为0.5696、0.8620,7月为0.8300、0.9282,8月为0.9083、0.8201,除6月龟纹瓢虫外,其余皆达显着或极显着水平;垂直格局上棉铃虫卵和龟纹瓢虫扩散系数和久野指数间相关系数分别为0.8211、0.7791,皆达极显着水平;水平格局上棉铃虫卵和中华草蛉扩散系数和久野指数间相关系数分别为0.7925、0.5228,分别达极显着和显着水平。     

Laboratory Effects of Ingestion of Azadirachtin by Two Pests ( Ceratitis capitata and Spodoptera exigua ) and Three Natural Enemies ( Chrysoperla carnea , Opius concolor and Podisus maculiventris )

The effects of azadirachtin on two pests: neonate larvae and newly emerged adults of Ceratitis capitata (Wiedemann) and last instar larvae of Spodoptera exigua (Hubner); and three natural enemies: newly emerged adults of Opius concolor Szepligeti, second instar larvae of Chrysoperla carnea (Stephens), and fifth instar nymphs of Podisus maculiventris (Say) were studied in laboratory. Adult insects were exposed to a non-oil formulation of azadirachtin (Align, emulsifiable concentrate, 3.2% azadirachtin, Sipcam Inagra, Spain) via their drinking water and immature instars were reared in the presence of the insecticide-treated diet. The natural enemies were exposed to at least the maximum field recommended concentration of the insecticide (0.15% v/v). Azadirachtin was highly toxic to neonate larvae of C. capitata and prevented adult emergence at a concentration of 1 mg a.i. l -1 . When adults were fed the insecticide at the maximum recommended concentration, their survival was not affected but egg laying was totally inhibited. Last instar S. exigua larvae were also very susceptible (LC 50 = 7.7 mg a.i. l -1 ) and at a concentration of 10 mg a.i. l -1 fecundity of surviving adults, and egg fertility, were reduced by 72 and 85%, respectively. Effects on O. concolor were large, and significant reductions in longevity, percentage of attacked hosts, and progeny size per female, were recorded. The predator P. maculiventris was much less sensitive to azadirachtin, but slight reductions in survival of emerged adults and of reproductive parameters occurred. The insecticide had no significant effect on C. carnea larvae fed with treated Sitotroga cerealella (Oliver) eggs, probably because of its inability to penetrate inside the egg.     

草间钻头蛛等对茶尺蠖的捕食功能反应研究

应用二次正交旋转组合设计方法,研究了茶园生态系统中3种捕食性天敌（草间钻头蛛、大草蛉和中华通草蛉）对茶尺蠖的捕食功能性反应。同时分析了猎物密度、捕食者自身密度、种内以及种间干扰对捕食功能的影响。结果指出：3种天敌及茶尺蠖自身密度的变化对于茶尺蠖的被捕食量存在明显的影响,其中草间钻头蛛密度的变化对总捕食量的影响最大。并且这3种天敌的种间和种内均存在着一定的干扰效应。     

草麻黄植株再生体系的建立

目的:以草麻黄的子叶为材料,建立草麻黄植株再生体系.方法:采用组织培养的方法进行了愈伤组织诱导、愈伤组织分化和不定芽生根研究.结果:MS+2,4-D 2.0mg/1+6-BA 1.0mg/l为诱导子叶形成具有分化能力愈伤组织的理想培养基;MS+2,4-D 1.5mg/l+6-BA 1.5mg/l是愈伤组织的最佳继代培养基;MS+IAA 0.2mg/l+TDZ 2.0mg/l是愈伤组织不定芽分化的最佳培养基,分化率为75%;试管苗生根培养基为MS+2,4-D 1.0mg/l.结论:建立了草麻黄子叶再生系统,为开发和保护麻黄野生资源提供一定的材料来源和技术方法.     

中华结缕草(Zoysia sinica Hance)组织培养和再生植株研究

以中华结缕草(Zoysiasinica Hance)成熟种子为外植体在附加2.5mg/L2,4-D、0.25mg/L6-BA和1～2mg/LVB₁的改良MS培养基(MS_m)上愈伤组织的诱导率最高为43.0%。愈伤组织的最佳继代培养基为MSm附加0.1mg/L6-BA和2.0mg/L2,4-D。在无生长调节物质的MS培养基(MS₀)上,外观呈白色到淡黄色、含有密实颗粒的愈伤组织再生率为30%～60%。     

盐度和温度对中华虎头蟹(Orithyia sinica) 存活和摄饵的影响

进行盐度和温度对中华虎头蟹存活和摄饵影响的试验,结果发现,盐度骤变时,盐度15—408d后蟹存活率100％。盐度10—45蟹能摄饵,日平均摄饵量达1．31g以上;盐度20—40是蟹适宜摄饵盐度,日平均摄饵量达3．65g以上;盐度30—35蟹摄饵最佳,日平均摄饵量达5．24g以上。盐度渐变时,盐度15—55蟹8d后存活100％;盐度5—50蟹能摄饵;盐度25—35为蟹摄饵适宜盐度,日平均摄饵量达4．13g以上;盐度30为最佳盐度,日平均摄饵量达4．53g。温度骤变时,10—30℃7d后蟹100％存活。10—35℃蟹能摄饵,日平均摄饵量达1．10g以上;20—30℃蟹摄饵最佳,日平均摄饵量逐渐增加,达8．76g以上。温度渐变时,0—30℃蟹7d后100％存活,35℃蟹存活率达80％。10—35℃蟹能摄饵;20—30℃蟹摄饵较佳,日平均摄饵量达12．61g以上;250C蟹摄饵最佳,13平均摄饵量达14．35g。     

枸杞木虱天敌的保护与利用

记录了12种枸杞木虱天敌,描述了3种主要天敌的生物学特性,提出了保护利用天敌的有效措施。     

十一星瓢虫对枸杞棉蚜的捕食作用研究

十一星瓢虫Coccinella undecimpunctata Linnaeus是青海省柴达木地区的一种重要捕食性天敌。为明确其对枸杞棉蚜Aphis gossypii Glover和枸杞木虱Poratrioza sinica Yang et Li.两种主要枸杞害虫的嗜好性,开展了捕食选择性试验,发现当两种害虫共存时,瓢虫成虫更喜食棉蚜。为进一步探究十一星瓢虫对枸杞棉蚜的捕食能力,测定了瓢虫各龄幼虫和成虫在不同棉蚜密度下的捕食量、寻找效应以及种内干扰、自身密度对捕食作用的影响。结果表明：十一星瓢虫各虫态对棉蚜的捕食功能反应均符合Holling-Ⅱ功能反应模型,种内干扰、自身密度对捕食量的影响分别符合Hassell干扰效应模型和Watt模型。十一星瓢虫1~4龄幼虫及成虫对枸杞棉蚜的日最大理论捕食量分别为18.94、44.29、81.57、145.27和126.48头;在一定空间、相同瓢蚜比条件下,瓢虫同一虫态个体间存在种内干扰效应,以1龄幼虫受干扰最大,干扰常数为1.1803。此外,瓢虫自身密度对其捕食作用产生一定影响,以4龄幼虫和成虫尤甚,竞争参数分别为0.7948、0.6848。本研究可为今后更高效地利用青海高原本地十一星瓢虫资源提供理论依据。     

中华通草蛉成虫抗寒能力季节性变化

中华通草蛉（Chrysoperla sinica）成虫在自然条件下抗寒能力的季节性变化研究表明,雌、雄成虫的抗寒能力均呈现出季节性的变化趋势,即随着冬季低温的到来,其抗寒能力逐渐增强,冬季过后又随气温的回升,其抗寒力逐渐减弱.雌、雄成虫的体内含水量、过冷却点（SCP）和结冰点（FP）均随气温的降低而降低,升高而升高,但体内总脂肪的含量却随气温的降低而升高,升高而降低.越冬代在越冬的前期和中期,雌、雄成虫体内的含水量和SCP均显著低于生长季节的其它各代,越冬代后期的含水量和SCP与生长季节其它各代没有显著差异.经回归分析发现,雌、雄成虫体内含水量与SCP之间均存在极显著负相关关系（p＜0.01）;越冬代成虫（特别是越冬前期）的体内总脂肪含量显著高于其它时期,并且雌成虫体内的总脂肪含量与SCP之间呈显著正相关（p＜0.05）,雄成虫体内总脂肪含量与SCP之间没有显著相关性（p＞0.05）.在一年的不同世代中,雌、雄成虫体内含水量只是在越冬前期有显著差异,SCP和体内总脂肪含量却在越冬后期有显著差异.