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131.
【目的】研究部分生态区散居型亚洲飞蝗形态特征的地理变异,分析亚洲飞蝗形态特征与生态适应性的关系。【方法】通过利用数值分类方法,测定与分析富蕴县、托克逊县、哈巴河县实验种群、和硕县、玛纳斯县、哈密市农十三师黄田农场庙尔沟地区,采集的散居型亚洲飞蝗标本的体长、前翅长度、前胸背板长度、前胸背板宽度、前胸背板高度、后足胫节长度、后足股节长度、头宽、头高、颜顶角等10个性状,将雌性与雄性成虫共有地理差异的性状进行系统聚类与主成分分析。【结果】雌性成虫不同地理种群体长、前翅长度、后足股节长度、前胸背板长度、前胸背板宽度、前胸背板高度、后足胫节长度等性状之间存在极显著差异,雄性成虫体长、前翅长度、前胸背板长度、前胸背板高度、颜顶角等性状之间存在极显著差异,不同地理种群亚洲飞蝗的雌雄成虫之间分化程度不一致。亚洲飞蝗的雌性与雄性成虫体长、前翅长度、前胸背板长度、前胸背板高度等性状不同地理种群之间都具有明显的差异性。各个性状之间存在相互促进,共同变异的现象。聚类分析结果中,6个地理种群分为两个类群,富蕴县、哈巴河县、和硕县地理种群聚为一个类群,玛纳斯县、哈密黄田庙尔沟、托克逊县聚为一类群。主成分结果中,暖温带荒漠气候托克逊县地理种群与暖温带大陆性干旱气候和硕县地理种群单独分布,而大陆性寒温带干旱气候富蕴县地理种群与大陆性北温带寒冷气候的哈巴河县实验种群分布在一起,属温带大陆干旱性气候的玛纳斯县地理种群与哈密市黄田庙尔沟地理种群分布在一起。【结论】分布于新疆富蕴县、托克逊县、哈巴河县实验种群、玛纳斯县、和硕县、哈密市农十三师庙尔沟生态区散居型亚洲飞蝗地理种群之间存在明显的形态变异现象,形态上的变异是否与生态环境因素有关尚不明确。 相似文献
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Between November 1998 and March 1999, bands of nymphs of Locusta migratoria were aerially treated using a ULV oil formulation of strain FI-985 of Metarhizium anisopliae var. acridum. At a dose of 3–4×1012 conidia/ha, there was <10% survival of locusts in treated sorghum crops, open grassland or open woodland with grass. Decline was less at lower doses or in dense woodland. During the first week after treatment, bands showed little change in numbers, but then rapidly declined in size and rate of movement. The decline was slower where vegetation was tall or dense, or where bands were large and moved out of the treated area a few days after spraying. In areas where bands were treated with Metarhizium, populations were suppressed in that few adult swarms formed. Adjacent untreated areas had many adult swarms which had to be controlled using chemical insecticides. Preventive locust control, as currently practised in Australia, involves beginning treatment when areas of band and swarm are small and the potential for direct damage limited. The clear demonstration that Metarhizium can suppress small local populations of L. migratoria indicate that it could be a valuable component of preventive control programmes against this species. The delay in mortality when treating with Metarhizium would be no impediment to its use in such programmes. 相似文献
133.
Guoxiong Peng Zhongkang Wang Youping Yin Dengyu Zeng Yuxian Xia 《Crop Protection》2008,27(9):1244-1250
During 2002–2006, nymph bands of Locusta migratoria manilensis (Meyen) were treated by ground and aerial applications in 6000 ha of grasslands and the nearby beach of Yellow river using a soybean oil miscible suspension ULV formulation of Metarhizium anisopliae var. acridum isolate CQMa102. The formulation was also applied in Tianjin, Henan, Hebei, Shandong and Shanxi provinces of Northern China by ground and aerial applications. During field studies, cage tests were carried out in corresponding field plots in order to estimate the mortality accurately. Doses of 3.3×1012 and 5.0×1012 conidia ha−1 were equally effective and caused 90% mortality 9–13 days after treatment. In the ground spray trial, 3.3×1012 conidia ha−1 killed >90% of L. migratoria manilensis 11–15 days after treatment in a wide variety of vegetation and weather conditions. The decline of locust populations was slower where vegetation was taller and denser. In the aerial spray treatment, the final percent survival of locusts was lowered to 10% at 11 and 14 days in the field cage and open field locusts, respectively. Furthermore, the M. anisopliae oil miscible suspension formulation did not appear to harm natural enemies of locusts in the field. 相似文献
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海南东亚飞蝗的发生与防治 总被引:1,自引:0,他引:1
根据多年对海南东亚飞蝗的防治经验,总结了其在海南的发生特点,提出了可行的综合防治方法。 相似文献
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为了探索东亚飞蝗视觉响应LED光信号的视敏反应效应,以明确东亚飞蝗趋光的光敏响应因子和生物光诱参数,利用LED光照和Ava Spec光纤光谱仪系统,在室内进行了东亚飞蝗视觉响应表征的光谱测定。并在此基础上,利用该波谱光照装置,验证其波谱光照调控东亚飞蝗的趋光反应及响应程度。测定结果显示,东亚飞蝗复眼吸收365、400、520、610 nm波长光照射后,其视觉响应波谱表现为380、402、540、602 nm的微光特征,当波谱光照强度增加时,东亚飞蝗视觉微光反应随之增强,且呈现时变效应的调控特性。东亚飞蝗视觉光敏调控的时变强度以紫光最优、依次是橙光和绿光最差,而其调控容度以橙光最优、绿光次之和紫光最差,紫外光较快的光敏聚集速度、紫光较强的光敏聚集程度和橙光较好的趋光效果说明,趋光光敏活性、趋光程度和趋光效果分别与视觉激发强度和视觉光敏调控的时变强度以及视觉光敏调控容度呈正相关,且东亚飞蝗视觉反应强度的光敏时效性影响其趋光行为选择和视觉光敏活性。因此,依据紫外光较强的激发效果、橙光较好的光敏时效性和紫光较强的光敏调控强度的特性,进行趋光视敏性光照时间的刺激调控,可以增强东亚飞蝗的趋光效果。该研究结果为蝗虫光诱捕机械装备的研制提供了理论基础和技术指导。 相似文献