稻褐飞虱致害性遗传与性别的关联性研究

以单雌蜜露排泄量和体重增量作为致害性指标,研究了稻褐飞虱Nilaparvata lugens (Stål)的致害性遗传与性别的关联性。褐飞虱弱致害种群（TN1种群）与强致害种群（Mudgo种群或ASD7种群）（已分别用水稻品种TN1、Mudgo和ASD7强迫饲养82代）在抗虫品种水稻上的致害力差异明显,适宜作为遗传分析的亲本材料。当用蜜露排泄量作为致害性指标时,两种处理（TN1种群与Mudgo种群,TN1种群与ASD7种群）正、反杂交的F₁代雌成虫平均蜜露排泄量存在极显著差异,由此可以推断正交F₁代群体与反交F₁代群体致害性存在明显差别。用体重增量作为致害性指标进行实验,得到的结论与上述研究完全一致。以上的结果可推测稻褐飞虱致害性可能属于伴性遗传。     

水稻品种抗褐飞虱不同生物型的稳定性

采用Tai氏方法分析估测12个水稻品种抗褐飞虱不同生物型的稳定性,以期为选育抗虫稳定性好的水稻品种提供较为有效的分析和监测方法.结果表明：光照强度、苗龄、施氮量对不同水稻品种对褐飞虱不同生物型的抗性表现及抗性稳定性有明显影响.抗褐飞虱生物型Ⅱ的品种中,RHT、RP1976-18-6-4-2、Ptb33的抗性较稳定,IR56的抗性不稳定,IR36、ASD7的抗性极不稳定;感褐飞虱生物型Ⅱ的品种中,TN1的感虫性稳定,桂华占、佛山油占、IR26的感虫性较稳定,国粳4号、Mudgo的感虫性不稳定.抗褐飞虱孟加拉型的品种中,RP1976-18-6-4-2、RHT、Ptb33的抗性不稳定,IR56的抗性极不稳定;感褐飞虱孟加拉型的品种中,桂华占、佛山油占、IR26的感虫性稳定;TN1、IR36的感虫性不稳定;国粳4号、Mudgo、ASD7的感虫性极不稳定.     

水稻OsLecRK1基因介导的抗褐飞虱功能分析

褐飞虱Nilaparvata lugens St(a)l是对水稻最具破坏性的害虫之一,OsLecRK1是水稻Bph3基因簇中对褐飞虱抗性贡献最大的基因.本文对RHTd(含Bph3)等材料进行了褐飞虱抗性评价,克隆并构建了OsLecRK1过量表达突变体水稻,利用该突变体分析了OsLecRK1基因对褐飞虱若虫存活率、若虫发育历期等生物学参数的影响.结果 表明,含Bph3基因水稻RHTd对褐飞虱的抗性明显地强于含Bph1基因水稻Mudgo和bph2基因水稻ASD7,RHTd水稻的褐飞虱受害指数仅为Mudgo和ASD7水稻的53.5％和24.1％.过量表达OsLecRK1基因能显著地增加水稻对褐飞虱的驱避性和抗生性,褐飞虱雌成虫偏好于在野生型水稻上产卵;突变体水稻上的褐飞虱若虫存活率显著地降低,仅为野生型水稻上若虫存活率的75.2％ ～81.8％,且若虫发育历期显著地延长,羽化率和初羽化雌成虫体重均显著地降低;此外,褐飞虱在突变体水稻上取食分泌的蜜露量只有野生型上的40.3％ ～ 60.9％,褐飞虱单雌产卵量只为野生型51％ ～61.2％,卵孵化率只有野生型的52.2％～56.7％,均显著地减少.结果 表明,含Bph3基因水稻RHTd对褐飞虱的抗性明显地高于分别含Bph1、bph2的水稻Mudgo和ASD7;水稻Bph3基因座的OsLecRK1单个基因过量表达即可显著增加水稻对褐飞虱的抗性,OsLecRK1协同影响褐飞虱的多个生物学参数降低褐飞虱的适合度.     

the differentiation of amino acid requirements in three host‐related populations of the brown planthopper,nilaparvata lugens (stål)*

Abstract In order to understand the differentiation of amino acid requirments in host‐related populations of the brown planthopper (BPH), Nilaparvata lugens (Stål), we established three BPH populations by separately maintaining them on three rice varieties, i.e. TN1 (common susceptible control), Mudgo (containing resistant gene Bph 1) and ASD7 (containing resistant gene bph2) for over 30 generations, and then reared them on 20 holidic diets, each with distinct overall amino acids and ratio of essential amino acid (EAA) to nonessential amino acid (NEAA). The emergence rate, brachypter rate, nymphal duration and weight of newly molted adults were evaluated and compared. The results showed significant difference among the three populations in the effect of amino acid variation on BPH performance, ascending in an order of Mudgo population ASD7 population > TN1 pupulation. The results also indicated that the required optimum concentrations of overall amino acids by BPH populations on Mudgo and ASD7 were 4.0% ‐4.8% and 4.0%, respectively, higher than that of TN1 population (2.4% ‐ 3.2%). In addition, it was found that Mudgo and ASD7 populations were more sensitive to the concentration of EAAs than TN1 population. We propose that there is substantial differentiation in responses to dietary amino acid conditions among different host‐associated BPH populations and that such differentiation may be closely related to the induced virulence shift on resistant rice varieties.     

THE VIRULENCE CHANGE AND DAMAGE CHARACTERISTICS OF VARIOUS GEOGRAPHIC POPULATIONS OF BROWN PLANTHOPPER*

Abstract The virulence change and damage characteristics of brown planthopper (BPH), Nilaparvata lugens Stal, populations collected from Guangxi, Yunnan and Zhejiang Provinces were studied by using various resistant rice varieties. The results indicated that the Zhejiang population could successfully infest varieties IR26 and Mudgo, showing the characters of BPH biotype 2 after 1989. The Guangxi population, however, could adapt the resistant varieties IR26, Mudgo and ASD7 after 1991. In 1997, the nymphal survival indices of Guangxi and Yunnan populations on Rathu Heenati (Bph3) were up to 70. 9 and 66. 7 respectively. This may imply that the BPH populations in Guangxi and Yunnan have shifted into a new biotype. In free-choice test, there was obvious difference in the feeding preference of nymphs and adults of Zhejiang population, the adult preferred to feeding on resistant variety IR26 and the nymphs chose the hosts randomly. Under 26 C and L12: D12, the nymphal duration of Zhejiang population was the longest in the three tested populations. For Guangxi population, the nymphal duration on ASD7 was significantly longer than on TN1, although it could infest resistant variety ASD7. The nymphal survival rate of Zhejiang population fed on IR26 was higher than those fed on TN1 and ASD7. On varieties IR26 and ASD7, an obviously higher nymphal survival rate was observed in Yunnan population as compared to those of Zhejiang and Guangxi populations. These results indicate that difference in virulence and damage characteristics could be found in different geographical populations of BPH.     

共生菌在褐飞虱致害性变化中的作用

研究了不同虫源和致害性褐飞虱Nilaparvata lugens种群体内共生菌数量动态及其对褐飞虱在抗虫品种上的取食选择、生长发育、繁殖以及氨基酸转移酶活性的影响。结果表明,褐飞虱田间种群的致害性与其体内共生菌数量有关。广西南宁种群雌成虫体内的共生菌数量显著地高于浙江杭州和龙游两个虫源的雌成虫体内共生菌数量,而已纯化的3个不同致害性生物型体内的共生菌数量无显著差异。取食抗性品种能显著减少生物型Ⅰ雌成虫体内的共生菌数量。缺乏共生菌时,生物型Ⅰ、Ⅱ若虫对水稻品种TN1和ASD7的选择性增大,而对Mudgo的取食选择性下降。尽管缺共生菌的3个生物型在已适应的和不适应的感虫和抗虫品种上的若虫存活率和雌成虫产卵量均下降,若虫历期明显延长,但在已适应品种上的变化程度明显小于在不适应的抗虫品种上的变化程度。共生菌还明显影响成虫体内丙氨酸氨基转移酶和天门冬氨酸氨基转移酶的活性。这些结果证明体内共生菌的数量和质量在褐飞虱对水稻致害性的变化中发挥了重要作用。     

褐飞虱对抗性水稻品种Mudgo个体致害性指标

在28±1℃下,观测了褐飞虱Nilaparvata lugens羽化24?h内短翅型雌成虫在敏感水稻品种TN1及抗性品种Mudgo上的寿命及体重增量。结果表明,取食抗性品种时,试虫的平均增重与寿命之间表现出明显的正相关。寿命在7天内的个体,存活期间平均体重增量为负值,而存活7天以上的个体则平均增重明显。进一步研究了初羽化的褐飞虱长翅型雌成虫在TN1及Mudgo上取食第1～4天的体重增量、寿命及产卵量,结果发现试虫在Mudgo上的这3个生物学参数之间存在明显正相关。其中,寿命及体重增量较好地反映出害虫个体对抗性品种的致害能力,可作为个体致害性指标。根据研究结果,提出将羽化后在Mudgo上存活7天以上或最初4天内体重增量大于0.1mg的雌成虫定为能够致害该抗性品种的个体。     

寄主经历对稻褐飞虱致害特性的影响

对寄主经历不同的稻褐飞虱Nilaparvata lugens 3龄若虫致害特性的研究结果表明：在抗虫品种Mudgo上的生活经历显著提高试虫在含Bphl基因的Mudeo、IR26、IR28、IR34上的蜜露排泄量、存活率及试虫对Mudgo的选择性：而ASD7上的经历仅显著提高试虫在ASD7上的蜜露量和存活率。不同品种上的经历对试虫的影响有所不同。同时,各经历试虫 在抗虫品种上的蜜露排泄量显著小于在TNl上的排泄量。     

褐飞虱致害性变异过程及其体内酶的变化

在室内连续用具不同抗虫基因的水稻品种TNl、IR26、Mudg。和ASD7、单管饲养褐飞虱(Nilaparvata lugens)种群,研究它对抗虫水稻品种的适应过程及其体内酶的变化规律。 结果表明：褐飞虱在抗虫品种上取食2代的若虫存活率、若虫历期和短翅成虫体重均明显比取食感虫品种TNl的低,第3代以后与取食TNl者基本相同。第2代是褐飞虱适应抗虫品种的关键期。天冬氨酸氨基转移酶(AST)、丙氨酸氨基转移酶(ALT)和丁-谷氨酰基转移 酶(GGT)的活性在关键的第2代最低,而超氧物歧化酶(SOD)和过氧化氢酶(CAT)的含量增加。褐飞虱在适应抗虫品种以后体内天冬氨酸氨基转移酶活性明显提高。     

Effects of nitrogen on the tolerance of brown planthopper, Nilaparvata Lugens, to adverse environmental factors

The effect of nitrogen content in rice plants on the tolerance of brown planthopper (BPH), Nilaparvata lugens Stal to high temperature, starvation and insecticide, was studied in the laboratory at International Rice Research Institute (IRRI), Philippines. Survival of nymphs and adults, fecundity and egg hatchability were significantly increased by the increase of nitrogen content in host plants at 38℃. Moreover, the survival of nymphs,fecundity and egg hatchability were significantly higher in BPH populations on rice plants with a high nitrogen regimen than those on rice plants with a low nitrogen regimen.Meanwhile, the tolerance of female adults to starvation and nymphs to growth regulator buprofezin on rice plants with a high nitrogen regimen were slightly increased. This indicates that the tolerances of BPH to adverse environmental stresses were positively increased by the application of nitrogenous fertilizer. The outbreak potential of BPH induced by the excessive application of fertilizer in rice fields was also discussed.     

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     

抗性水稻品种对褐飞虱和白背飞虱种群参数的影响

在半自然状态下 ,用生命表方法初步比较了褐飞虱Nilaparvatalugens和白背飞虱Sogatellafurcif era在 4个抗褐飞虱水稻品种ASD7,IR3 6,JX89和Mudgo上的种群参数。初步的结果表明 ,白背飞虱在 4个抗褐飞虱水稻品种上具有较高的繁殖率 ,较短的发育时间和较大的种群增长。对褐飞虱各种群参数影响最大的是JX89,对白背飞虱影响最大的是Mudgo。与感性品种TN1比较 ,这些抗褐飞虱的水稻品种对 2种稻飞虱均具有不同程度的抗性。这些结果说明 ,抗褐飞虱水稻品种对白背飞虱同样具有一定的抗性 ,但白背飞虱对这种抗性具有较强的适应性 ,如果在一个地区长期推广抗褐飞虱的水稻品种 ,势必会导致白背飞虱的大发生     

Mechanisms of resistance to the brown planthopperNilaparvata lugens in wild rice (Oryza spp.) cultivars

Three wild rice species and six cultivated rice varieties were evaluated to determine their mechanisms of resistance toNilaparvata lugens (Stal.). Wild rice species,Oryza officinalis, O. punctata, andO. latifolia and cultivated rices Rathu Heenati (Bph 3), Babawee (bph 4), ARC 10 550 (bph 5), Swarnalata (Bph 6), Ptb 33 (bph 2+Bph 3) and the susceptible Taichung Native (TN 1) (no resistance gene) were included in the study. In a free choice seedbox screening test, wild rice species maintained their high level of resistance through the 48 h exposure toN. lugens nymphs while plant damage ratings of cultivated rice varieties increased with time. Wild rices were non preferred and significantly more individuals settled on susceptible TN 1 followed by cultivated rices. The quantity of food ingested and assimilated byN. lugens on wild rices was less than on cultivated resistant varieties.N. lugens caged on resistant wild rices had slow nymphal development, reduced longevity, low fecundity, and low egg hatchability as compared toN. lugens on cultivated resistant varieties.     

温度和氮肥对褐飞虱存活、生长发育和繁殖的交互作用

在实验室条件下,研究了不同温度（20 ℃、23 ℃、26 ℃、29 ℃和32 ℃）和氮肥水平（不施氮：0 kg·hm^-2;高氮：250 kg·hm^-2）对褐飞虱存活、发育和繁殖的影响和交互作用.结果表明：在20 ℃~29 ℃范围内,随着温度的升高,褐飞虱的卵孵化率和若虫存活率提高,卵和若虫历期缩短,成虫寿命缩短,同时产卵量增加;32 ℃时, 褐飞虱卵孵化率和若虫存活率降低、卵和若虫历期延长、成虫生殖力降低;在不同温度下,高氮植株上的褐飞虱卵孵化率和若虫存活率、成虫生殖力均明显高于低氮稻株上的褐飞虱,同时高氮植株上褐飞虱的卵和若虫历期明显短于低氮稻株上的褐飞虱,说明施用高水平氮肥提高了褐飞虱对逆境条件的生态适应性;温度和氮肥对褐飞虱卵存活率、若虫历期和产卵量的交互作用显著,表明全球气候变暖和长期施用高水平氮肥很可能是近年来褐飞虱猖獗暴发的重要原因.     

水稻品种对褐飞虱的田间抗性及其生态学机制

评价了7个水稻品种(浙粳22、宜香845、中组14、秀水123、二优倍九、感虫对照品种TN1和抗虫对照品种IR36)在田间成株期对褐飞虱Nilaparvata lugens(Stl)的抗性表现,并初步分析了它们的抗性机制。结果表明,在田间网室人工诱发条件下,浙粳22、宜香845、秀水123和中组14等4个品种的抗性水平与抗虫品种IR36相同,均小于3级,表现为抗虫,而二优培九则与感虫品种TN1相同,表现为感虫。在自然发生条件下的水稻分蘖期至乳熟期,宜香845和中组14上褐飞虱数量仅为TN1上的7.84%～24.44%,秀水123和浙粳22则为TN1上的30.19%～60.27%。在4个抗性品种上褐飞虱的产卵量和卵孵化率明显减少,而若虫存活率仅为TN1上的20%～30%。与IR36相同,4个抗性品种上褐飞虱的若虫存活率和种群增长倍数均显著低于TN1上,说明他们对褐飞虱的抗性主要表现为抗生性。     

不同虫源和致害性的褐飞虱体内共生菌的种群动态

通过对不同地理种群和致害性的褐飞虱体内共生菌,在高温和抗性水稻品种作用下的种群动态研究表明,在正常湿度下褐飞虱体内共生菌的数量随若虫的生长发育而增加,5龄若虫期是共生菌增长的关键期;同一种群的褐飞虱秋季共生菌数量明显高于夏季。广西田间种群的短翅雌虫体内的共生菌数量显高于浙江省的杭州和龙游种群,经高温处理后,3个生物开共生菌数量均显减少,但其子代共生菌的数量在正常温度下马上恢复,与未经高温处理的褐飞虱共生菌数量基本相同,取食抗性品种的生物型1和田间种群的褐飞虱体内的共生菌数量均明显减少,取食抗性品种的第2代的共生菌又均比第1代少。这说明高温对共生菌的影响是暂的,而抗性品种的对共生菌的作用与褐飞虱种群对品种的适应性有关。     

水稻品种对褐稻虱的抗性

本文运用苗期抗性筛选法,测定了9个水稻品种对褐稻虱的抗性及其与秧龄的关系,表明秧龄对高抗品种的抗性表现影响不显著,而部分中抗品种的抗性则随秧龄增长而加大。抗性机制研究证明:高抗品种7105具有很强的不嗜性和抗生性;而包选2号和辐包矮21等中抗品种则以耐虫性为主,兼有不同程度的抗生性。     

Feeding rates and carbohydrate metabolism by Bemisia tabaci (Homoptera: Aleyrodidae) on different quality phloem saps

Abstract.The effects of water stress on phloem sap quality of the melon, Cucumis melo, and how this, in turn, has an impact on the sweet potato whitefly, Bemisia tabaci were studied. Melon plants were grown under watering regimes that produced plants with or without water stress. Plants showed strong developmental responses to the treatments; water-stressed plants were shorter, with fewer, smaller leaves than those without stress. There was, however, no effect of plant water stress on the development period of whiteflies feeding on these plants, or on the weights of male or female adults. Honeydew production was used as an indirect measure to test whether the absence of insect developmental or behavioural effects was due to differential phloem sap ingestion. Feeding rates on the stressed plants were almost half those on unstressed plants, and there was also variation in the daily pattern of honeydew production. Phloem sap and honeydew were analysed to determine why the feeding behaviours differed. Amino acid composition of the phloem sap was similar in both groups of plants, but carbohydrate concentrations were greater in water-stressed plants, indicating that lower feeding rates may have been due either to the physical or nutritional quality of the phloem sap. The honeydew of insects that were feeding on water-stressed plants contained a greater concentration of carbohydrate than those on unstressed plants, and was composed of a significantly greater proportion of glucose and the disaccharide, trehalulose. This isomerization of more complex sugars from those in the diet suggests that B. tabaci uses a mechanism of osmoregulation to actively maintain its internal water status. It is concluded that transient conditions of water stress in this host plant do not affect the development of B. tabaci, due to physiological and behavioural changes in response to diets with different nutritional and physical properties. The implications of this finding for the feeding biology of B. tabaci on desert-grown crops are discussed.     

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。     

Comparative transmission of, and varietal reaction to, three isolates of rice tungro virus disease

Comparative transmission by leafhoppers of three tungro isolates obtained from the Philippines, India and Malaysia, and of an infectious clone of the Philippine isolate of rice tungro bacilliform virus (RTBV) by agroinoculation, was conducted on 12 rice cultivars. The symptoms, including height of inoculated plants were recorded and the efficiency of RTBV and rice tungro spherical virus (RTSV) transmission was determined by enzyme-linked immunosorbent assay. In most cases, the reduction of height and leaf symptoms of plants infected with RTBV and/or RTSV by the three isolates were similar in any given cultivar. On cultivar ASD 7 , the Malaysian isolate showed more severe yellow orange leaf discolouration symptoms than the Indian isolate which in turn had more severe leaf discolouration than the Philippine isolate. On the other hand, cultivars ASD 7 and Ptb 18 produced the most severe yellow orange leaf discolouration when agroinoculated with an infectious RTBV clone of the Philippine isolate. There was some variation in the transmission profile of the two tungro viruses among the three isolates. However, there was no one clear set of characteristics by which one could use cultivars to distinguish isolates. The amount of viral DNA in agroinfected plants of cultivars Utri merah, Balimau putih, Utri Rajapan and ARC 11554 was low, while the amount was high in cultivars TN1, ASD7, Ptb 18 and TKM 6. There was high correlation between the amount of viral coat protein by ELISA and viral nucleic acid by DNA hybridisation on 10 agroinoculated rice cultivars; this might indicate that similar proportions of the total RTBV DNA are encapsidated in each cultivar.