利用PEG6000模拟研究干旱胁迫对褐飞虱取食和产卵的影响

 在实验室条件下,以感虫品种TN1、抗虫品种IR36和抗旱品种旱优3号为材料,采用聚乙二醇6000（PEG6000）模拟干旱处理水稻植株,研究干旱胁迫对褐飞虱取食和产卵的影响。结果表明,在同一水稻品种上,褐飞虱雌成虫在稻株上数量随着PEG6000浓度的上升而显著减少（P<0.001）,而褐飞虱若虫在不同PEG6000浓度处理的水稻植株上数量无显著差异（P=0.093）。褐飞虱雌成虫在48 h内的蜜露分泌量和在稻株上72 h内的产卵量均与PEG6000浓度呈显著负相关。在感虫品种TN1上,褐飞虱若虫在不同浓度PEG6000处理稻株上的分布无显著差异;而在抗旱品种旱优3号和抗虫品种IR36上,随着PEG6000浓度的上升,水稻基部的褐飞虱若虫数量明显增多。在TN1和旱优3号上,褐飞虱雌成虫蜜露分泌量随PEG6000浓度上升而显著减少;而在IR36上,褐飞虱雌成虫在不同浓度PEG6000处理水稻植株上的蜜露分泌量均很少且无显著差异。     

水稻品种对白背飞虱的抗性及其与稻株营养成分的关系

 研究了6个水稻品种在不同苗龄对白背飞虱的抗性与稻株营养成分的关系。结果表明、抗性品种 ARC10239、Rathu Heenati(RH)和中抗品种 N22、Mudgo 对白背飞虱的取食、存活和产卵有抑制作用:品系9101虽适宜于白背飞虱的取食和存活,但自孕穗期后严重影响其产卵。分蘖期后,品种抗性随苗龄增加而逐渐增强.这种趋势在中抗品种 N22和 Mudgo 上特别明显。稻株营养成分测定显示出稻株内的总氮和游离氨基酸(主要是亮氨酸和丙氨酸)的含量与品种抗性呈显著负相关。     

呋喃丹对白背飞虱的致死与拒食作用

 就呋喃丹对白背飞虱雌成虫的致死与拒取食作用进行了研究。采用叶鞘涂抹接、点滴法和根部施药法施用呋喃丹以后，观测白背飞虱的死亡率和取食反应。呋喃丹对白背飞虱的致死中浓度(LD₅₀分别为：0.51 μg／cm² (叶鞘涂抹法)，0.86 μg／g(点滴法)和8.82μmol／L(根部施药法)。其中， 点滴呋喃丹对飞虱最有效。当白背飞虱在呋喃丹以0.016μg／cm²涂抹在感虫品种TN1稻株叶鞘上和将稻株根部浸入0.1 μmol／L药掖里，以及在每头飞虱上点滴0.002 ng后， 飞虱在这些处理过的稻株上取食后其蜜露排泄量明显减少。白背飞虱在用呋喃丹处理过TN1根部的稻株上的取食行为也采用一种电子装置进行了监测。     

电子记录稻飞虱取食和产卵行为及其在植物抗虫性研究中的应用

采用AC型电子记录系统(EMS)对褐飞虱在非寄主植物稗草和具有抗性基因bph4的水稻品种Babawee上的取食行为进行了比较研究.结果表明,褐飞虱口针到达稗草韧皮部以前停止取食,这揭示了在稗草非韧皮部组织中存在拒食剂.而在抗虫品种上,口针到达韧皮部以后取食行为终止.因此,可以清楚地识别两类具有不同抑制取食抗性因子的抗性植物.分析白背飞虱产卵行为的电子记录表明,在大多数情况下,就旺盛生长的水稻植株的下半部分而言,白背飞虱产卵器插入植物组织中但不产卵.这表明旺盛生长的植株能诱导白背飞虱的产卵行为,但由于某些拒避性因素使整个产卵过程不能完成.因此,这一系统可以有效地识别具有产卵抗性的植物上行为序列中受到破坏的步骤.     

施氮对白背飞虱在水稻上适应性的影响

 以杂交稻组合汕优63、常规粳稻品种秀水63和常规籼稻品种浙733为材料,采用室内继代饲养的方法,研究了不同类型水稻品种上施用氮肥对白背飞虱生长发育、存活率和繁殖等的影响。结果表明,施用氮肥可以显著提高白背飞虱种群生态适应性。同一水稻品种,在施用氮肥的植株上白背飞虱若虫历期缩短,随着取食代数的增加,在不施氮稻株上的若虫历期明显延长,而在施氮稻株上的若虫历期则明显缩短。白背飞虱若虫存活率随着施氮而显著提高,品种和饲养代数对其存活率也均有着极显著的影响。在施氮水稻植株上的白背飞虱雌成虫体质量和产卵量均显著高于不施氮肥上的。随着饲养代数的增加,同一品种的施氮稻株上雌成虫体质量、产卵量及卵孵化率均增加,而在不施氮稻株上则相反。水稻品种、饲养代数和氮肥水平对白背飞虱雌成虫体质量和产卵量均有着极显著的影响。     

稻株挥发物在调节褐飞虱、白背飞虱种内种间关系中的作用

以TN1为供试水稻品种,研究了稻株挥发物在褐飞虱、白背飞虱寻找寄主及调节两种飞虱种内种间关系中的作用。结果表明健康稻株挥发物对褐飞虱、白背飞虱具有明显的引诱作用。当稻株被一种飞虱为害12 h后,其所释放的挥发物对另一种飞虱有明显的引诱作用,但对同种飞虱则无显著的吸引或驱避作用。随着为害程度的加重（为害1 d以上）,两种飞虱均避开虫害株而趋向健康稻株。     

水稻纹枯病菌侵染稻株对褐飞虱发生的影响

病原菌侵染引发植株防卫基因表达的信号传导途径水杨酸途径(SA)与虫害(机械损伤)诱发的植物防御信号传导途径茉莉酸途径(JA)会同时存在,且两种信号途径间存在着相互抑制的拮抗作用。本试验结果表明,水稻植株受到纹枯病菌侵染之后,褐飞虱在RH的感病植株和健康植株中明显倾向于选择感染纹枯病菌的RH水稻植株;但在不同水稻品种上的取食行为以及蜜露排泄量及蜜露氨基酸含量的测定均未发现褐飞虱对于感染纹枯病的抗、感水稻品种有显著的取食趋性。说明抗、感褐飞虱的水稻品种感染纹枯病之后并未显现出更易感虫的性状。     

水稻抗褐飞虱遗传和育种研究

综述了水稻抗褐飞虱基因资源的鉴定及其分布特点、水稻抗褐飞虱主基因定位和QTL分析、水稻抗褐飞虱遗传的“基因对基因”关系以及水稻品种对褐飞虱的抗虫机制与褐飞虱对抗虫品种的适应等4个方面的研究进展，同时简述了抗褐飞虱基因的育种利用现状，并对今后抗褐飞虱遗传和育种利用研究作了展望。     

抗白背飞虱水稻品种挥发生性次生物质的提取、组分鉴定与生测

 采用水蒸汽蒸馏－乙醚同时萃取装置对抗白背飞虱品种Rathu Heenati(RHT)，IR64，Nabeshi和感虫对照品种TN1稻株进行挥发性次生物质提取，浓缩所得精油，经“气谱－质谱”（GC-MS）联机机检测出64个有机的化学组分，其中366主要分子结构为：9种醇，9种醛，7种酮，4种酯，3种烷烃，2种酸，烯和杂环人经合物各1种。2-已烯醛，β-紫罗兰酮，叶醇（反式），叶绿醇，3,5,5-三甲-3-环已烯-1-酮和水杨酸甲酯的含量较高。将蒸馏提取物回喷在TN1稻株上，白背飞虱对抗虫和感虫稻株蒸馏提取物的趋性没有显著差异。嗅觉仪测定飞虱的趋性结果表明，单体化合物苯甲醇和己烯醛比对照丙酮更易吸引白背飞虱。在回喷TN1蒸馏提取物、丙酮溶液和未处理的TN1稻株上，白背飞虱分泌的蜜露量明显较Nabeshi和IR64蒸馏提取物处理过的TN1稻株上分泌的高。白背飞虱从掺有蒸馏提取物和挥发物单体的营养液中吸食的量均比从单纯营养液中的少；抗虫品种RHT蒸馏提取物对白背飞虱拒食作用最强，β－紫罗兰酮和己烯醛次之。     

水稻品种对稻飞虱抗性鉴定方法的比较研究

采用苗期群体筛选、苗期单株鉴定、分蘖盛期单株鉴定、蜜露量测定和若虫发育历期测定5种方法,分别测定了6个新近育成的、不同类型的水稻优质、高产新品种对褐飞虱和白背飞虱的抗性反应。多数品种在苗期接虫鉴定情况下的抗性表现都是一致或十分接近的,而且与品种的类型和抗感性无关。但少数品种随着苗龄的增大,其抗虫性有不同程度的提高。蜜露斑面积测定结果与分蘖盛期接虫鉴定结果基本吻合,初步将蜜露斑面积与抗性级别的关系拟定为：蜜露斑面积［mm2/(雌虫·d)］ 0～100.0≈ 0～3级,100.1～200.0≈5级,>200.1 ≈ 7～9级。综合多项测定指标,认为分蘖盛期接虫鉴定较苗期鉴定更能准确地反映水稻品种成株期的抗性水平;苗期群体筛选和蜜露量测定是水稻抗飞虱的两个快速、便捷、准确的鉴定方法。     

Feeding behaviour of whitebacked planthopper, Sogatella furcifera (Horvath), on resistant and susceptible rice varieties

Feeding behaviour of the whitebacked planthopper Sogatella furcifera (Horvath) was studied on 30-, 45- and 60-day-old plants of seven resistant varieties and one susceptible variety of rice. The preference or otherwise of the hoppers to different varieties was studied in terms of the feeding marks made and the amount of honeydew excreted. The insect made more feeding marks and excreted less honeydew on resistant varieties than on the susceptible TN 1. The number of feeding marks increased with the increase in the plant age of varieties, while the honeydew excretion decreased.     

水稻植株防御白背飞虱为害的某些生理反应

 以对白背飞虱具有不同抗性水平的水稻品种(组合) 为材料, 研究了水稻在白背飞虱为害后稻株体内的生理变化。结果表明, 稻株受害后, 感虫品种(TN1和汕优63) 光合作用速率和叶绿素含量下降比抗虫品种(N 22) 明显; 感虫品种超氧化物歧化酶(SOD) 活性增加, 过氧化物酶(POD) 和过氧化氢酶(CAT) 活性下降, 而抗虫品种POD 和SOD 均增加, CAT减少;感虫品种除丙氨酸含量下降外, 其他氨基酸含量均上升, 尤其是天门冬氨酸、苏氨酸、缬氨酸及蛋氨酸等含量增加很快, 抗虫品种中天门冬氨酸、缬氨酸等含量增加也很快, 但苏氨酸、蛋氨酸、丙氨酸的含量显著下降。     

褐飞虱IR56种群的致害特征

含Bph3抗褐飞虱基因的水稻品种自20世纪80年代在东南亚推广后,迄今仍对褐飞虱有较好的抗性,受到我国抗褐飞虱育种专家的重视。在IR56水稻(含Bph3基因)上连续40多代胁迫饲养获得褐飞虱IR56寄主种群,从褐飞虱的生长、发育、繁殖以及水稻品种的抗感反应(SSST法测定)两方面对该种群的致害性进行了研究。结果表明:1)在抗性水稻IR56上,褐飞虱IR56种群的羽化率、初羽化成虫体质量、成虫寿命、产卵量、蜜露排泄量、体质量增量等均较褐飞虱TN1种群显著增加,若虫历期则显著缩短;与感虫水稻TN1上的IR56种群或TN1种群相比,除成虫寿命、蜜露排泄量和体质量增量显著下降外,羽化率、产卵量、卵孵化率无显著差异,初羽化成虫体质量、若虫历期尽管差异显著但数值上较接近(其差值不及IR56水稻上IR56种群与TN1种群差值的1/2)。2)水稻品种苗期抗性反应显示IR56水稻对褐飞虱IR56种群的抗性级别为7级,明显弱于对褐飞虱TN1种群的3级,但略强于TN1水稻对褐飞虱IR56种群或TN1种群的9级。显然,与褐飞虱TN1种群相比,褐飞虱IR56种群对抗性水稻IR56有较强的致害能力,与IR56种群或TN1种群对TN1水稻的强致害水平尽管有一定的差距,但多数指标较为接近。含Bph3基因的水稻品种RathuHeenati对IR56种群抗性为1级,推测可能与该水稻品种存在Bph3以外的其他抗虫基因有关。     

Susceptibility to Insecticides and Ecological Fitness in Resistant Rice Varieties of Field Nilaparvata lugens Stl Population Free from Insecticides in Laboratory

A population of rice brown planthopper(BPH) Nilaparvata lugens collected from a paddy field in Hangzhou was successively reared on susceptible rice Taichung Native 1(TN1) in a laboratory free from insecticides for more than 14 generations. The changes in susceptibility to insecticides and ecological fitness on different resistant rice varieties were monitored in each generation. The resistance ratio to imidacloprid sharply declined with the succession of rearing generations without insecticides from 359.94-fold at F1 to 6.50-fold at F14 compared with the susceptible strain, and the resistance ratio to chlorpyrifos was from 9.90-fold at F1 to 5.94-fold at F14. Nymphal duration and weights of newly hatched female adults were significantly affected by rice variety, generation and their interactions, but nymphal survival was significantly affected by the generation only. The ratio of brachypterous adults in males was affected by the generation and generation × variety interaction, whereas no difference was found in females. Nymphal duration extended with increasing generations, and the female nymphal duration was shorter in the susceptible variety TN1 than those in the resistant varieties IR26 and IR36. In addition, the female adult weight in TN1 was higher than those in IR26 and IR36. These results indicated that the resistance of field BPH population to insecticides was reversed after several generations of no-exposure to insecticides, and the ecological fitness in TN1 was higher than those in IR26 and IR36. These findings suggested the rational and reduced use of insecticides in combination with the manipulation of resistant rice varieties would be effective for BPH management.     

Virulence of the Populations of the Whitebacked Planthopper, Sogatella furcifera Reared on Different Resistant Rice Varieties

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.     

Virulence of the Populations of the Whitebacked Planthopper, Sogatella furcifera Reared on Different Resistant Rice Varieties

ARC and ND colony were obtained by rearing the whitebacked planthopper (WBPH), Sogatella furcifera(Horvath), exclusively on ARC10239 (ARC, carrying resistance gene Wbph2) and N‘Diang Marie (ND, carrying resistance gene WbphS) 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%0) and RHT(21.0%), while that of ARCcolony 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.     

Resistance of wild rices, Oryza spp., to the brown planthopper, Nilaparvata lugens (Stål) (Homoptera: Delphacidae)

Of the 128 wild rices screened, 83 accessions were resistant to the brown planthopper Nilaparvata lugens (Stål). Resistant accessions were non-preferred and significantly more individuals settled on susceptible TN1 plants than on resistant ones. The quantity of food ingested and assimilated by N. lugens on resistant accessions was less than on susceptible TN1. N. lugens caged on resistant accessions had slow nymphal development, reduced longevity and low fecundity. Two wild rice species, Oryza officinalis and O. punctata, reduced the percentage hatchability of N. lugens eggs. A significant reduction in population growth was observed on resistant accessions compared with susceptible TN1.