茭白害虫长绿飞虱与稻田缨小蜂关系的研究

茭白害虫长绿飞虱 Saccharosydne procerus是稻虱缨小蜂Anagrus nilaparvatae 在稻田外的主要寄主之一。茭白田可为稻田提供大量的稻虱缨小蜂,从而提高对稻田稻飞虱的控制能力。从褐飞虱和长绿飞虱卵中羽化的稻虱缨小蜂均明显地选择寄生褐飞虱卵,对长绿飞虱卵的寄生率也较高。长绿飞虱在水稻上不能完成其生活史。因此,稻田和茭白田的合理布局可有效地提高稻田缨小蜂的数量,从而提高该寄生蜂对有关害虫的生防效益。     

水稻品种和稻虱缨小蜂对褐飞虱协同作用的模拟分析

利用我们先前的试验结果和文献资料,组建了水稻品种－褐飞虱－稻虱缨小蜂３者相互关系的模拟模型．模拟分析表明水稻品种能直接和间接地通过物理或化学特性影响稻虱缨小蜂的寄生作用,其中以影响褐飞虱卵垂直分布型、稻虱缨小蜂的迁入时间、未成熟期历期和怀印量等的水稻品种特性起主要作用．同时,模拟分析还表明中等抗性的水稻品种,配以增强稻虱缨小蜂寄生作用的品种特性,就能有效地控制褐飞虱的危害．文中还就协调水稻品种抗性与天敌协同控制褐飞虱的途径进行了讨论．     

两种稻虱缨小蜂种群生态的比较

在南京市郊和我国南方稻区,寄生稻飞虱卵的缨小蜂主要是稻虱缨小蜂Anagrus nilaparvatae Pang et wang和拟稻虱缨小蜂A.paranilaprvatae Pang et Wang两个种.这两个种在田间的种群消长,呈明显“此起彼落”的季节性交替.作者以比较生态学方法探讨了产生这一现象的原因.夏季30℃以上高温对稻虱缨小蜂未成熟期的存活和雌虫产卵有明显抑制作用,但拟稻虱缨小蜂具有耐高温能力.稻虱缨小蜂和拟稻虱缨小蜂种群增长的理论最适温度分别为27.41℃和31.87℃,最适温度下的种群内禀增长力以稻虱缨小蜂为高.当供以白背飞虱和褐飞虱卵时,拟稻虱缨小蜂只寄生褐飞虱卵,稻虱缨小蜂对褐飞虱卵也有明显的喜好.两种缨小蜂对褐飞虱卵密度的功能反应均符合Holling Ⅱ型.     

稻虱缨小蜂(Anagrus nilaparvatae)在两种稻飞虱上的生殖力及其应用潜能

利用寄生变红卵和仔代成蜂数量作为繁殖力估计等方法,编制了稻虱缨小蜂(Anagrus nilaparvatae pang and wang)在褐飞虱(Nilaparvata lugens (St(a)l))卵和白背飞虱(Sogatella furcifera (Horvath))卵上繁殖的实验种群生命表,测定了稻虱缨小蜂寄生褐飞虱和白背飞虱的生殖力,分析了稻虱缨小蜂对稻飞虱卵的寄生能力.结果表明:在相同的繁蜂条件下,稻虱缨小蜂寄生褐飞虱卵的净生殖力R0为10.26,内禀增长率rm为0.2213,平均单雌产仔数为14.52头;寄生白背飞虱卵的净生殖力R0为8.78,内禀增长率rm为0.1840,平均单雌产仔数为12.20头.两组生命表参数比较分析显示褐飞虱卵具有较强的室内繁蜂潜能,可利用其进行室内繁蜂.应用稻虱缨小蜂、褐飞虱及白背飞虱的生命表参数讨论了稻虱缨小蜂在稻飞虱生物防治中的应用潜能及其可能的利用途径.     

稻田飞虱卵寄生蜂群落结构和动态的初步研究

报道了广东省四会市大沙镇稻田中褐飞虱Nilaparvata lugens卵期寄生蜂的结构和动态。该群落由缨小蜂科和赤眼蜂科的6个属、共19种卵寄生蜂组成。其中,稻虱缨小蜂Anagrus nilaparvatae、长管稻虱缨小蜂A. longitubulosus和拟稻虱缨小蜂A. paranilaparvatae是群落中的优势种群,它们对控制褐飞虱种群卵期的存活率起主要作用。6个属在群落中的优势地位相对稳定,但不同物种包括优势种类在群落中的地位并不稳定。早、晚稻前期,群落的寄生蜂数量与稻田褐飞虱数量正相关;中期,寄生蜂数量在一定的范围内波动;后期,其数量先上升,然后急剧下降。水稻生长前、中和后期,寄生蜂对褐飞虱卵的平均寄生率分别约为76%,70%和50%。     

水稻品种对稻虱缨小蜂发育、存活及繁殖的影响

水稻品种既能直接地经物理结构,亦能间接地通过改变褐飞虱Niladarvatalugens(Stal)卵的适宜性,影响稻虱缨小蜂Anagrus nilaparvatae Pang et Wang的发育、存活和繁殖。稻虱缨小蜂的羽化率、怀卵量分别与其寄主褐飞虱卵所处水稻品种叶鞘鞘脊的硅细胞密度呈极显著和显著负相关;同时,怀卵量和虫体大小还与受水稻品种影响的褐飞虱卵粒大小呈极显著正相关。稻虱缨小蜂种群增长能力指数的组分分析表明,不同水稻品种影响稻虱缨小蜂种群增长能力的主要因子不同,显示了水稻品种对稻虱缨小蜂影响的多因子作用。     

稻飞虱卵寄生蜂——缨小蜂的研究(三)——三种缨小蜂寄生行为的选择性

<正> 缨小蜂Anagrus spp.是飞虱卵期主要的寄生性天敌。我们在稻田已发现寄生于飞虱卵的缨小蜂五种,其中稻虱缨小蜂、拟稻虱缨小蜂和长管稻虱缨小蜂的群体数量较大,对稻田飞虱所起控制效用较为显著。在对这三种缨小蜂的生物学特性进行研究过程中,我们初步观察不同缨小蜂种类,对于不同飞虱种类所表现寄生行为的选择性。本文主要报道这方面的观察结果。     

二种稻虱缨小蜂空间寄生习性的观察

观察结果:拟稻虱缨小蜂喜选择寄生稻株中上部叶位和分蘖枝组织内的褐飞虱卵;稻虱缨小蜂喜选择寄生稻株下部叶位组织内灰飞虱、白背飞虱卵及主茎枝组织内白背飞虱卵和分蘖枝组织内灰飞虱卵。二种稻虱缨小蜂均表现喜选择寄生叶片组织内寄主的习性。这一空间寄生习性的表现,本文从稻株空间温度对缨小蜂寄生活动的影响及寄主产卵部位、稻株组织结构等方面进行了综合分析和讨论。     

稻飞虱卵期寄生蜂稻虱缨小蜂引诱剂的筛选与田间试验(英文)

植食性昆虫的天敌能够利用虫害诱导的挥发物进行有效的寄主或猎物定位。为了开发稻飞虱卵期天敌稻虱缨小蜂Anagrus nilaparvatae Pang et Wang的引诱剂,分别在室内和室外检测了多种褐飞虱诱导的水稻挥发物组分对褐飞虱卵期天敌稻虱缨小蜂的引诱作用。Y型嗅觉仪实验结果表明,5种单一化合物,Z-3-己烯乙酸酯,1-戊烯基-3-醇,Z-3-己烯醛,芳樟醇和水杨酸甲酯,以及3种混合物,水杨酸甲酯+Z-3-己烯醛,Z-3-己烯醛+Z-3-己烯乙酸酯+芳樟醇,水杨酸甲酯+Z-3-己烯醛+Z-3-己烯乙酸酯+芳樟醇,对稻虱缨小蜂具有明显引诱作用。田间试验表明,3种单一化合物,Z-3-己烯乙酸酯,Z-3-己烯醛和芳樟醇,以及一种混合物,水杨酸甲酯+Z-3-己烯醛+Z-3-己烯乙酸酯+芳樟醇,能明显提高稻虱缨小蜂对褐飞虱卵的寄生作用。这些结果对于改善褐飞虱治理具有重要的意义。     

虫害诱导抗性水稻挥发物增强邻近感性水稻品种对褐飞虱的直接和间接抗性

【目的】褐飞虱Nilaparvata lugens是为害水稻的重要害虫。本研究旨在明确褐飞虱为害诱导的抗性水稻品种(IR64, ASD7和IR56)挥发物对感性品种TN1抗虫性的影响,为褐飞虱的绿色生态防控提供理论和技术指导。【方法】以水稻-褐飞虱-稻虱缨小蜂Anagrus nilaparvatae为研究对象,利用未被为害和经褐飞虱雌成虫为害(褐飞虱为害诱导)的水稻(IR64, ASD7, IR56和TN1)挥发物处理TN1植株,测定TN1植株上褐飞虱单雌产卵量和单雌蜜露分泌量、若虫存活率和卵孵化率;分别利用H型嗅觉仪和Y型嗅觉仪测定褐飞虱雌成虫和稻虱缨小蜂对上述不同处理TN1植株的选择性。【结果】褐飞虱为害诱导的抗性水稻挥发物处理TN1植株后均可降低褐飞虱单雌产卵量,而未被为害的抗性水稻挥发物处理后不影响褐飞虱单雌产卵量。健康TN1植株经褐飞虱为害诱导的IR64挥发物处理后可降低单雌蜜露分泌量,但对卵孵化率和若虫存活率无影响;同时还降低对褐飞虱的引诱作用,而增强对稻虱缨小蜂的引诱作用。且健康TN1植株经褐飞虱为害IR64和TN1诱导的挥发物处理后,其挥发物组分中仅2-庚酮的相对含量发...     

Preference and performance of Anagrus nilaparvatae (Hymenoptera: Mymaridae): effect of infestation duration and density by Nilaparvata lugens (Homoptera: Delphacidae)

The effect of Nilaparvata lugens (St?l) infestation duration and density on the host preference and performance of Anagrus nilaparvatae Pang et Wang, an egg parasitoid of rice planthoppers, was determined. The results showed that the parasitoid preferred N. lugens eggs on the plants infested with 10 gravid N. lugens females for 1 d to those plants infested with 10 gravid females for 2 or 3 d. It was also found to prefer N. lugens eggs on plants infested with 10 or 20 adult females after 24 h of infestation to those plants infested with 5 or 80 females. The parasitoid's offsprings had lower survival rates, fecundities, female ratios, indexes of capacity for population increase, and longer developmental durations on plants when they were infested with high N. lugens density (80 adult females per plant). However, the performance of the parasitoid on plants infested with low N. lugens density (5 female adults per plant) was similar to those on plants with intermediate N. lugens density (10 or 20 adult females per plant). Low preference of the parasitoid for N. lugens eggs on plants with heavy or light infestation levels may be correlated with low host suitability and detectability, respectively. The result implies an important role of herbivore-induced rice volatiles in the host preference of the parasitoid A. nilaparvatae, by which the parasitoid perceives the host and its suitability.     

Quantitative genetic analysis of biotypes of the brown planthopper Nilaparvata lugens: heritability of virulence to resistant rice varieties

The virulence of Nilaparvata lugens Stål (Homoptera: Delphacidae) to a resistant variety of rice, Oryza sativa L., is suggested to be under polygenic control. To determine whether the virulence of N. lugens is a quantitative character that has continuous distribution or a threshold character that has a few discontinuous phenotypic forms and is determined by some underlying continuous variable, I examined the frequency distribution of honeydew excretion that has been used as a measure of ability of attacking the rice plants, and the relationship between honeydew excretion and the oviposition rate of N. lugens females using a japonica rice line Saikai 190 which has a resistance gene Bph 1. The frequency distribution in honeydew excretion significantly differed from the normal distribution, but two distributions below and above 10 mg honeydew excretion for two days did not significantly deviate from normality, suggesting a bimodal distribution. There were significant differences in the proportion of females ovipositing and the number of eggs deposited between the female groups that excreted 0–10 mg honeydew and more than 20 mg honeydew. Within these female groups, however, the reproductive performances were not different. Thus, virulence of N. lugens can be analyzed as a threshold character that has two distinct phenotypes, virulent and avirulent. I estimated the heritabilities of the virulence of N. lugens by parent-offspring regression using the percentage of virulent females in a full-sib family. The estimates of heritability were 0.41 on Saikai 190 and 0.55 on ASD7, carrying the bph 2 gene. These results show that the N. lugens population has substantial genetic variation in virulence. The regression coefficients on female and male parents were similar, suggesting similar genetic contributions by both parents. When the parental families were examined on Saikai 190 and the progeny on ASD7, the regression coefficient approached zero. There may be a low genetic correlation between virulences to the two varieties.     

水稻品种形态特征对稻虱缨小蜂功能反应的影响

在室内研究了水稻品种形态特征对褐飞虱卵在稻株上的分布以及由此而对稻虱缨小蜂功能反应的影响.结果表明,在所有测试品种中,褐飞虱卵在稻株上的垂直分布型可归为3类,即上中部为主分布型、中下部为主分布型和均匀分布型.稻株上、中、下各部位的褐飞虱卵量多少与其相应部位叶鞘鞘脊的相对高度呈极显着正相关.稻虱缨小蜂对上中部为主分布型褐飞虱卵(在浙农大40上)的功能反应明显地强于对中下部为主分布型的褐飞虱卵(在浙852上).     

水稻品种形态特征对稻虱缨小蜂功能反应的影响

在室内研究了水稻品种形态特征对褐飞虱卵在稻株上的分布以及由此而对稻虱缨小蜂功能反应的影响．结果表明,在所有测试品种中,褐飞虱卵在稻株上的垂直分布型可归为３类,即上中部为主分布型、中下部为主分布型和均匀分布型．稻株上、中、下各部位的褐飞虱卵量多少与其相应部位叶鞘鞘脊的相对高度呈极显著正相关．稻虱缨小蜂对上中部为主分布型褐飞虱卵（在浙农大４０上）的功能反应明显地强于对中下部为主分布型的褐飞虱卵（在浙８５２上）．     

FAR gene enables the brown planthopper to walk and jump on water in paddy field

Many insects can live on water and survive being caught in the rain. Current research has shown that insect cuticular hydrocarbons(CHC) confer desiccation resistance to maintain water balance. In this study, we identified a fatty acyl-CoA reductase gene(NlFAR) of the rice brown planthopper, Nilaparvata lugens that is essential for the production of CHCs, and found that NlFAR is essential for N. lugens to walk and jump on water when moving from one rice plant to another in paddy fields. NlFAR was mainly expressed in the integument at the beginning of each molt. Cuticular surface analysis by scanning electron microscopy and characterization of CHC extracts indicated that N. lugens with knockdown of NlFAR using RNA inference(RNAi)had a neater epicuticle layer and a significant decrease in CHC contents. Knockdown of NlFAR did not influence the desiccation resistance of N. lugens, but the ds NlFAR-treated insects were easily adhered and moistened by water droplets or their own secreted honeydew and unable to walk or jump on water. These results suggested that NlFAR is a crucial enzyme for CHC biosynthesis and cuticle waterproofing, but not for water retention of N. lugens, which may provide a potential strategy for pest management.     

Multi-generation effects of Bt rice on Anagrus nilaparvatae, a parasitoid of the nontarget pest Nilapavarta lugens

Little is known about the potential cumulative long-term effects of transgenic crops on nontarget organisms. In the present laboratory study, the potential cumulative effects of transgenic Bacillus thuringiensis (Bt) rice on parasitoids in successive generations were observed for an egg parasitoid, Anagrus nilaparvatae parasitizing eggs of Nilaparvata lugens (St?l) (Hemiptera: Delphacidae) feeding on Bt rice. Enzyme-linked immunosorbent assay test confirmed that Cry1Ab insecticidal protein could be detected in newly eclosed parasitoid adults. However, no significant effect on the fecundity of Anagrus nilaparvatae Pang et Wang (Hymenoptera: Mymaridae) was observed between Bt and non-Bt rice. Developmental times of both genders of A. nilaparvatae parasitizing host eggs laid in Bt (KMD1 and KMD2) rice lines were significantly prolonged from first generation to second generation, but not always prolonged from third generation to 11th generation as compared with the control rice line. Furthermore, the sex ratio of A. nilaparvatae progeny from the first generation to 11th generation in three rice lines was not significantly different. In general, our results suggested that the effect of Bt rice on this parasitoid could be negligible.     

褐飞虱Nl15基因的克隆及功能分析

【目的】植食性刺吸式口器昆虫的唾液蛋白参与调控植物抗虫防御反应,影响其对寄主植物的适应性。本研究旨在通过克隆褐飞虱Nilaparvata lugens重要唾液蛋白基因Nl15,调查其时空表达模式,明确其在褐飞虱致害性中的作用。【方法】基于褐飞虱IR56种群转录组数据,用RT-PCR克隆褐飞虱基因Nl15 cDNA序列,并进行生物信息学分析。利用qPCR检测其在褐飞虱TN1和IR56种群不同发育阶段(卵、1-5龄若虫和雌雄成虫)和雌成虫不同组织(头、胸、腹和足)中的表达模式。通过显微注射dsRNA对褐飞虱TN1和IR56种群的4龄若虫进行Nl15的RNAi,利用qPCR检测Nl15 RNAi后褐飞虱若虫中Nl15的相对表达量以及Nl15 RNAi后褐飞虱若虫取食3 d时水稻植株中防御相关基因(OsLecRK4, OsMPK10, OsWRKY24, OsLox, OsNPR1和OsGns5)的相对表达量,并生物测定Nl15 RNAi后褐飞虱的存活率以及成虫蜜露量和体质量增量。【结果】克隆了褐飞虱Nl15 cDNA序列(GenBank登录号：OK181113),其开放阅读框长1 008 bp;预测编码335个氨基酸,理论等电点为7.54,分子量为38.7 kD,含有23个氨基酸的信号肽序列和一个糖基化修饰位点,不存在跨膜结构域和其他已知的功能域;Nl15与灰飞虱Laodelphax striatellus同源蛋白氨基酸序列一致性为45%。发育表达谱结果表明,Nl15在褐飞虱各个发育阶段均表达,在3-4龄若虫中的表达量最高;组织表达谱结果表明,Nl15在褐飞虱雌成虫头部中的表达量最高,且在IR56种群头部中的表达量高于在TN1种群头部中的。RNAi实验结果表明,与注射dsGFP的对照组相比,注射dsNl15的处理组中Nl15的表达量显著降低了89.5%,褐飞虱的存活率以及成虫蜜露量和体质量增量均显著降低,上述6个水稻防御相关基因的表达量显著上调。【结论】褐飞虱IR56种群中的Nl15参与褐飞虱与水稻的防御与反防御分子互作。本研究为进一步阐述褐飞虱克服抗虫基因的机制及揭示昆虫与植物互作的分子网络提供了思路。     

水稻品种抗性对褐飞虱和白背飞虱种群动态的影响

用ＴＮ１、Ｎ２２、ＡｓＤ７和Ｐｔｂ３３等４个抗虫性差异明显的水稻品种测定了褐飞虱和白背飞虱在它们上面的栖息率、落卵量、卵存活率、若虫存活和发育状况,以及后代种群数量表现。结果表明,Ｐｔｂ３３通过减少２种飞虱的栖息率、落卵量,降低卵和若虫存活率,延长若虫的发育时间,抑制后代的种群数量增长,表现出明显的抗性。Ｎ２２对白背飞虱、ＡｓＤ７对褐飞虱的后代种群建立与发展均表现明显的抑制作用。２种飞虱在ＴＮ１上