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191.
作者于1974、1982和1983年三个冬季,在福州、闽侯、沙县、宁德、霞浦等地,进行田间白背飞虱越冬调查,得知福建省1月份均温8~10℃左右的地区,白背飞虱以卵越冬。初冬田间可见成虫和个别老龄若虫活动,成虫于12月中旬之前,在再生稻和杂草寄主上产卵,然后成虫逐渐死亡,终见于1月中旬。越冬卵发育缓慢,早春孵化,是第二年田间白背飞虱的初次虫源。  相似文献   
192.
捕食性天敌对白背飞虱种群的控制作用   总被引:3,自引:0,他引:3  
本文根据白背飞虱自然种群生命表及捕食性天敌对白背飞虱种各虫态的捕作用讨论捕食性天敌对白背飞虱种群的控制作用,得到如下结果:捕食性天敌是影响白背飞虱种群密度的生要因子。白背飞虱种群动态应用状态方程描述。经计算白背飞虱各虫期在排除捕食性天敌作用后的存活率估计状态方程系统矩阵的元素值,由捕食性天敌作用所导致的死亡率估计得到捕性天敌控制作用矩阵各元素值,把模型模拟值与田间实测值作比较可见:在水稻分蘖期两者  相似文献   
193.
 为探求稻飞虱鸣声在预测预报和物理防治上应用的可能性,室内引诱试验结果表明:1)褐稻虱和白背飞虱的鸣声是性成熟个体用以识别、联络同种异性,刺激性兴奋,完成交尾的求偶信号,其沿固体介质(寄主植株)传播,试虫可感觉距离在60—80cm 以内,45cm 以内较为敏感。2)性成熟的雄性及未交尾的雌性个体均常主动鸣叫,在听到异性鸣声时,雄虫表现为兴奋、骚动并积极循鸣声寻觅雌虫;雌虫亦以鸣声相和但很少移动。3)求偶鸣声具有种的专一性,两种飞虱均只对同种异性鸣声敏感。4)以相应的鸣声录音代替活虫,其引诱效果无显著差异。  相似文献   
194.
ARC and ND colony were obtained by rearing the whitebacked planthopper (WBPH), Sogatella furcifera gene Wbph5) till 15 generations. Taichung Native 1 (TN1) and Rathu Heenati (RHT) served as susceptible and resistant check, respectively. The results of electronic recording revealed that duration of salivation and X-waveform of the two colonies on their corresponding hosts was short while the duration of phloem ingestion was long. The amount of honeydew excreted by ARC and ND colony did not differ on their corresponding host varieties from TN1 and was much higher than that of RHT. The number of eggs laid on their host varieties and TN1 were significantly higher than that on RHT. No distinct change was observed for these two colonies in term of percentage of developed eggs. The nymph survival rate of ND colony on its selection host was 45.0%, significantly different from that on TN1(71.4%) and RHT(21.0%), while that of ARC colony was 68. 3 %, not significantly different from that on TN1 (77.5 %), but much higher than that on RHT(22.6 %).The nymphal development duration of these two colonies on the corresponding hosts was not different from that on TN1, but significantly shorter than that on RHT. In brief, these two colonies had almost adapted to their corresponding host varieties based on feeding and oviposition, but the nymphal survival rate of ND colony was still low.  相似文献   
195.
本文采用灯光诱捕和田间系统调查相结合的方法,调查和分析了2009~2013年贵州道真县白背飞虱Sogatella furcifera(Horváth)种群消长动态。结果表明:白背飞虱在道真县1年可发生6代;不同年份间灯下白背飞虱始见日基本一致,集中于5月上、中旬;5年中灯诱白背飞虱高峰日和单日发生量存在差异,2012年最早出现高峰日,单日诱虫量达17650头,2013年高峰日诱虫量仅为130头;全年灯诱总虫量在不同年份间存在较大差异。不同年份早栽田白背飞虱发生量与晚栽田的基本持平,2010年白背飞虱发生高峰日集中在7月中旬和8月中旬,2011年和2012年白背飞虱发生高峰日集中在7月中旬;两种类型田中白背飞虱长翅型成虫所占比例较高。  相似文献   
196.
The rice leaffolder (RLF), Cnaphalocrocis medinalis Guenée (Lepidoptera:Pyralidae), and the white-backed rice planthopper (WBPH), Sogatella furcifera Horváth (Hemiptera: Delphacidae), are major insect pests in China and several other Asian countries. These two pests commonly occur simultaneously or in a temporal sequence. Thus, the investigation of the effect of complex infestations or temporal sequence infestations by these pests on rice yield has a practical signiifcance for the control of these pests. The present study comprised experiments with the following four different variables in potted rice at the tillering stage:single pest species infestation, complex infestation, complete combination infestation and temporal sequence infestation (C. medinalis infestation prior to S. furcifera and S. furcifera infestation prior to C. medinalis). The results showed that the four infestations resulted in a signiifcant decrease in 1 000-grain weight (1 000GW) and rate of yield loss (RYL) but an increase in blighted grain rate (BGR), with a signiifcant positive correlation with the infestation density. However, the inlfuences of the complex infestation, complete combination infestation or sequence infestation on the 1 000GW, BGR and RYL were greater than those of the single pest species infestations but did not have addition effects, i.e., the effects of the complex infestation and combination infestation or sequence infestation on the 1 000GW, BGR and RYL were less than the additive effects of the two single pest species infestations at the same densities. In the condition of the same total infestation pressure, no signiifcant differences in the 1 000GW, BGR and RYL were found between C. medinalis infestation prior to S. furcifera and S. furcifera infestation prior to C. medinalis as well as between the sequence infestation and the complex infestation.  相似文献   
197.
水稻抗白背飞虱基因Wbph2的初步定位   总被引:1,自引:2,他引:1  
 鉴定了ARC10239/明恢63 F2群体对白背飞虱的抗性,混合F2感虫稻株的DNA,构建感虫池。应用129个RFLP探针,结合4种限制性内切酶,检测抗虫亲本ARC10239、感虫亲本明恢63和感虫DNA池的多态性。检测到6个阳性探针,分布在5个染色体上(染色体3、6、8、11和12)。应用阳性探针分析了F2群体的142个个体,发现抗虫基因Wbph2与第6染色体上的标记RZ667、RG64和RG264连锁,其中, Wbph2与RZ667的遗传距离为25.6 cM (LOD=4.50)。  相似文献   
198.
【目的】探究白背飞虱Sogatella furcifera与红腹缢管蚜Rhopalosiphum rufiabdominalis种间互作机制,以及2种昆虫互作过程中水稻次生代谢物质的作用。【方法】将白背飞虱和红腹缢管蚜按不同比例混合饲养,待白背飞虱长至成虫后分组配对,分析白背飞虱总产卵量及日均产卵量;测定各处理的水稻草酸、黄酮及总酚含量,利用GC/MS仪器分析各处理水稻幼苗次生代谢物质成分的差异。【结果】“15头蚜虫+5头白背飞虱”处理的白背飞虱总产卵量仅为131.67粒,与“20头白背飞虱”处理(214.60粒)差异显著,日均产卵量也呈现相同的规律;“15头蚜虫+5头白背飞虱”处理的水稻黄酮和总酚含量分别为1.98和63.71 mg/L,均显著高于其他处理。GC/MS分析表明,“15头蚜虫+5头白背飞虱”处理的水稻中丙丁酚相对含量高达75.78%,而其余处理的水稻中不存在此种酚类物质。【结论】红腹缢管蚜可能是通过刺激水稻提高黄酮及总酚含量,进而抑制白背飞虱的生殖能力,其中丙丁酚可能在白背飞虱和红腹缢管蚜种间互作中起着关键作用。  相似文献   
199.
Southern rice black-streaked dwarf virus (SRBSDV) is one of the most damaging rice viruses. The virus decreases rice quality and yield, and poses a serious threat to food security. From this perspective, this review performed a survey of published studies in recent years to understand the current status of SRBSDV and white-backed planthopper (WBPH, Sogatella furcifera) transmission processes in rice. Recent studies have shown that the interactions between viral virulence proteins and rice susceptibility factors shape the transmission of SRBSDV. Moreover, the transmission of SRBSDV is influenced by the interactions between viral virulence proteins and S. furcifera susceptibility factors. This review focused on the molecular mechanisms of key genes or proteins associated with SRBSDV infection in rice via the S. furcifera vector, and the host defense response mechanisms against viral infection. A sustainable control strategy using RNAi was summarized to address this pest. Finally, we also present a model for screening anti-SRBSDV inhibitors using viral proteins as targets. © 2023 Society of Chemical Industry.  相似文献   
200.
为探明水稻应对白背飞虱取食胁迫的生理基础,分析了3个水稻品种(Rathu Heenati、R9810–T和丰源优272)在白背飞虱取食胁迫不同时间(0、3、6、12、18、24、30和36 h)的部分生理指标的变化。结果表明,在白背飞虱取食胁迫下,水稻Rathu Heenati丙二醛(MDA)和过氧化氢(H2O2)含量变化小,R9810–T和丰源优272丙二醛和过氧化氢含量随胁迫时间延长呈上升趋势;3个水稻品种超氧化物歧化酶(SOD)和过氧化物酶(POD)活性都随胁迫时间延长呈上升趋势,Rathu Heenati过氧化氢酶(CAT)活性变化小,R9810–T过氧化氢酶活性呈下降趋势,丰源优272过氧化氢酶活性先下降后稍回升;3个品种谷胱甘肽过氧化物酶(GPX)活性变化小。白背飞虱取食胁迫下,水稻品种Rathu Heenati比R9810–T和丰源优272受到的氧化伤害少。  相似文献   
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