烟草品种、育苗方式和烟蚜来源对烟蚜茧蜂寄生能力的影响

【目的】本研究旨在筛选出适合烟蚜茧蜂Aphidius gifuensis寄生烟蚜Myzus persicae的烟草品种、育苗方式和烟蚜来源,为烟蚜茧蜂人工繁殖和复壮提供科学参考。【方法】采用盆栽法,调查了不同烟草品种(云烟87、K326、翠碧1号和红花大金元)繁殖烟蚜若蚜、不同来源烟蚜(来自烟区、来自非烟区和室内繁殖种群)若蚜和烟草不同育苗方式(土壤育苗和湿润育苗)繁殖烟蚜若蚜时,烟蚜茧蜂成蜂对烟蚜若蚜的寄生率以及成蜂羽化率、寿命、体型大小和雌蜂比。【结果】结果表明,不同烟草品种繁殖烟蚜若蚜对烟蚜茧蜂成蜂寄生率存在显著影响。其中,在红花大金元和翠碧1号繁殖烟蚜上的烟蚜茧蜂成蜂寄生率分别比在K326繁殖烟蚜上的烟蚜茧蜂成蜂寄生率高19.00%和14.00%,但对烟蚜茧蜂的其他指标没有显著影响;不同烟蚜来源对烟蚜茧蜂寄生率也存在显著影响,其中,烟蚜茧蜂成蜂对非烟区烟蚜若蚜和烟区烟蚜若蚜的寄生率比对室内繁殖种群烟蚜若蚜的寄生率分别高20.25%和16.75%,但对烟蚜茧蜂成蜂的羽化率、寿命、体型大小和雌蜂比没有显著影响;烟草不同育苗方式对烟蚜茧蜂成蜂的寄生率无显著影响。【结论】烟蚜茧蜂对烟蚜...     

烟草对烟蚜的抗性品种筛选及抗性机制研究

[目的]探明烟草对烟蚜Myzus persicae(Sulzer)的抗性机制,为烟草抗性品种的选育及烟蚜的综合防治提供理论依据。[方法]采用新叶子圆片法测定烟蚜在20个烟草品种上的发育历期、繁殖力、存活率等,并测定了20个烟草品种鲜叶可溶性蛋白质含量、pH值、叶绿素含量及叶背茸毛数量。[结果]在不同烟草品种上烟蚜的选择性、成虫寿命、繁殖力、若蚜历期及存活率差异显著。其中闽烟38、贵烟3号和云烟97更感虫,而闽烟57、闽烟7号和中烟102具有较强的抗虫性。不同烟草品种鲜叶片中pH值的差异并不显著,但叶背茸毛密度、可溶性蛋白质含量、叶绿素a和叶绿体色素含量差异显著,且与烟蚜成虫量呈极显著正相关,这表明烟蚜更喜食叶背茸毛密度高、可溶性蛋白质含量高、叶绿素含量高的烟草品种。[结论]20个烟草品种中,闽烟57、闽烟7号和中烟102具有较强的抗虫性。选育背茸毛密度低、可溶性蛋白质含量低、叶绿素含量低的品种,可提高烟草对烟蚜的抗性。     

烟蚜在烤烟田分布动态的地统计学分析

烟蚜属半翅目蚜科,是烟田的重要迁飞性害虫,成蚜和若蚜聚集于烟叶幼嫩部位,吸食植物汁液,滋生霉污病并传播烟草病毒病害,造成产量和质量损失.本文在湖北恩施地区选择烤烟田对烟叶从移栽至中部烟叶开始采收阶段的田间有翅烟蚜和无翅烟蚜的空间分布和发生动态进行调查,并通过地统计学方法分析其半变异函数特性,模拟其田间迁移模式.结果表明:恩施烟区有翅烟蚜种群动态为双峰曲线,烟叶移栽后第3周和烟叶打顶后第2周为发生高峰,呈现随机、聚集、随机、聚集、随机5步过程;无翅烟蚜种群动态为单峰曲线,烟叶打顶前为发生高峰,呈现随机、聚集、随机3步过程;人为因素和寄主特性对其种群密度影响较大;空间分布模拟插值图可以清晰反映出田间烟蚜的发生动态,结合Pearson相关分析发现,有翅蚜迁入高峰期,烟蚜种群数量小并高度集中,构成了田间烟蚜的虫口基数,是烟蚜防治的关键时期.     

烟蚜在山东烟田的发生与消长

对山东烟区烟蚜Myzus persicae(Sulzer)的发生消长规律进行7年的系统调查。结果表明:烟蚜的发生为单峰型曲线,发生高峰大致在每年的5月底6月初,大多数年份不能形成第2个蚜量高峰,且烟蚜的发生以无翅蚜为主。并对以无翅蚜为主以及近年来烟蚜田间发生的数量较少的原因进行分析。     

大豆蚜对环境的适应及对大豆产量的影响

2009-2010年,以辽东山区大豆主产区岫岩县作为试验点,系统调查了大豆蚜Aphis glycines Matsumura正常型蚜和小型蚜的种群动态,研究了蜡蚧轮枝菌Verticillium lecanii(Zimmerman)Viegas、豆柄瘤蚜茧蜂Lysiphlebus fabarum Marshall、异色瓢虫Harmonia axyridis(Pallas)对大豆蚜正常型蚜和小型蚜的寄生与捕食作用;另外,也研究了降雨对小型蚜和正常型蚜的冲刷作用,以及小型蚜对大豆产量的影响等。研究结果表明,7月上中旬为大豆蚜小型蚜发生初期,7月下旬—8月上旬为小型蚜发生高峰期,2010年小型蚜平均蚜量达10000头/百株以上。此外,通过比较大豆蚜正常型蚜和小型蚜排蜜量,发现正常型蚜与小型蚜在30min内的排蜜频率差异极其显著,正常型蚜排蜜次数明显多于小型蚜。蜡蚧轮枝菌对大豆蚜小型蚜的侵染较正常型低,前者被侵染率低于3%,后者被侵染率高达25%。豆柄瘤蚜茧蜂对正常型蚜的寄生率较小型蚜高,寄生率分别为43.41%和0.58%。异色瓢虫3龄幼虫对正常型蚜和小型蚜的捕食率分别为80.24%和36.36%。降雨对小型蚜冲刷作用明显低于正常型蚜。最后,通过对单株蚜量与单株产量进行单因素方差分析,结果表明,单株小型蚜量对产量影响不显著(F=0.378;df=7,1;P>0.05)。上述研究为明确大豆蚜的发生与为害、小型蚜适应环境的生存机制以及自然天敌对大豆蚜的田间控制作用,进而为大豆蚜的可持续控制提供理论依据。     

B型烟粉虱取食诱导烟草对烟蚜防御反应的时间效应

为了明确B型烟粉虱Bemisia tabaci取食诱导烟草对烟蚜Myzus persicae的防御反应和时间效应,探讨外来入侵害虫B型烟粉虱取食诱导的烟草防御反应在其与桃蚜种间竞争中的作用,本研究采用小叶笼法和生化分析法,分别研究了B型烟粉虱取食诱导烟草对烟蚜生长发育的影响和烟草主要营养指标的变化。结果表明：B型烟粉虱取食诱导的烟草可对烟蚜产生明显的防御反应,对烟蚜的存活和生长发育有显著的抑制作用和时间效应。在烟粉虱若虫危害烟草至第5天,烟草系统白脉叶片上烟蚜的死亡率较对照叶片上烟蚜的死亡率升高36.13%;至第10天死亡率升高72.78%,且平均相对生长率较对照显著降低;至第15天死亡率升高仍达58.89%。在烟粉虱若虫危害至第10天时,将处理植株上的烟粉虱的若虫虫体去除,然后在烟草系统白脉叶片上接烟蚜1龄若蚜,在去虫后15 d内,烟草系统白脉叶片对烟蚜死亡率及相对生长率的影响较不去虫的对照间均有明显差异（P<0.05）。但至去虫后第20天,对烟蚜的不利影响即消失。研究表明B型烟粉虱取食诱导的烟草系统白脉叶片对烟蚜的抗性能持续表达15 d左右。烟粉虱危害后的局部带虫叶片与对照相比,对烟蚜的生长发育没有明显的不利影响。B型烟粉虱危害的烟草,其可溶性糖和可溶性蛋白的含量降低,这与烟蚜的死亡率表现出显著的负相关性。     

贵州烟草产区烟蚜种群对啶虫脒、溴氰菊酯和抗蚜威的抗性

【目的】为明确贵州烟草产区烟蚜Myzus persicae种群对常用杀虫剂的抗性水平。【方法】在室内采用浸渍法测定了贵州省9个地州市34个烟叶主产县市的烟蚜种群对啶虫脒、溴氰菊酯和抗蚜威3种杀虫剂的抗性。【结果】对贵州9个地州市34个烟叶主产县市的烟蚜种群对3种杀虫剂抗性监测结果表明:除黔西南(兴义)和毕节(黔西)2个县市的烟蚜种群对啶虫脒处于敏感性下降水平(RR=4.00~4.31)外,其余32个县市的烟蚜对啶虫脒均已产生中等水平抗性(RR=10.09~26.35);毕节(毕节)和黔东南(天柱)2个县市的烟蚜种群对溴氰菊酯产生了中等水平抗性(RR=32.47~38.72),毕节(黔西)、铜仁(思南)和安顺(安顺)3个县市的烟蚜对溴氰菊酯已达到极高水平抗性(RR=184.97~237.77),其余县市的烟蚜均已产生高水平抗性(RR=51.27~132.08);除毕节(黔西)、黔东南(施秉、天柱)和遵义(余庆)4个县市的烟蚜种群对抗蚜威产生低水平抗性(RR=5.90~9.46)外,其余县市的烟蚜均已产生中等水平抗性(RR=10.05~31.66)。【结论】当前贵州烟草产区多数县市的烟蚜种群对3种杀虫剂产生低水平至极高水平抗性,可能与田间广泛地大量使用有关。本研究的抗性检测结果对贵州烟草产区烟蚜的杀虫剂种类选择及田间合理用药等具有重要指导作用。     

烟蚜茧蜂寄生对烟蚜生长发育和繁殖的影响

【目的】为探究烟蚜茧蜂Aphidius gifuensis对烟蚜Myzus persicae寄生后烟蚜生长发育和繁殖影响及其在烟蚜防控中的作用。【方法】采用室内叶片培养皿法,测定了不同龄期烟蚜(1-4龄若蚜及成蚜)被烟蚜茧蜂寄生后烟蚜当代(F₀)及后代(F₁)的发育历期、寿命、产仔量。【结果】烟蚜1龄若蚜被烟蚜茧蜂寄生后,1龄若蚜历期受到显著影响,较未被寄生对照缩短了0.65 d (33.00%),而2-4龄若蚜期和成蚜历期未受显著影响;2龄若蚜被寄生后,4龄若蚜和成蚜历期均受到显著影响,较未被寄生的对照分别缩短了1.50 d (100.00%)和0.83 d (100.00%),而2和3龄若蚜期未受显著影响;3龄若蚜被寄生后,4龄若蚜和成蚜期均受到显著影响,较未被寄生对照分别缩短了1.50 d (100.00%)和0.83 d (100.00%),而3龄若蚜期未受显著影响。2龄若蚜被寄生后烟蚜的寿命和产仔量均受到显著影响,寿命较未被寄生对照缩短了8.39 d(54.00%),每雌产仔量较未被寄生对照减少了48.67头(100.00%)。此外,2-3龄若蚜被寄生后其后代(F₁)1龄若蚜历期受影响最大,较未被寄生烟蚜后代1龄若蚜期缩短了0.80 d(40.00%),其F₁代平均寿命较未被寄生烟蚜后代平均寿命延长了5.72 d(41.20%),但其产仔量与对照差异不显著。【结论】不同龄期烟蚜被烟蚜茧蜂寄生后,其发育历期和寿命比未被寄生的缩短,产仔量比被未寄生的少,但其F₁代平均寿命比未被寄生后代烟蚜的长且其产仔量未受显著影响。当代2龄若蚜期是控制烟蚜增长的关键时期。这些结果对确定烟蚜茧蜂防治烟蚜适期及认识其机理具有重要参考意义。     

一种扩繁烟蚜茧蜂的载体植物适合性评价

为评估平卧菊三七作为载体植物扩繁烟蚜茧蜂的适合性,测试了烟蚜在平卧菊三七、以及常见寄主植物烟草、茄子和二年生萝卜共4种寄主植物上的发育历期和繁殖力等,获得了净增殖率、周限增长率、内禀增长率、平均世代周期、种群加倍时间等主要生命表参数,比对了不同载体植物上的烟蚜对烟蚜茧蜂个体发育的影响。结果显示:这4种寄主植物上烟蚜的发育历期为二年生萝卜(22.79 d)平卧菊三七(22.22 d)烟草(22.01 d)茄子(18.92 d),茄子上最短,其他三种寄主植物上无显著差异;单头烟蚜总产仔量为二年生萝卜(63头)平卧菊三七(52头)茄子(43头)烟草(41头);内禀增长率rm值为茄子(0.283)二年生萝卜(0.278)平卧菊三七(0.277)烟草(0.255)。表明相同条件下,相对于烟草,烟蚜偏好取食平卧菊三七;平卧菊三七作为载体扩繁出的烟蚜茧蜂僵蚜,体型与烟草、二年生萝卜扩繁者的差异不显著。平卧菊三七可用作大量扩繁烟蚜及烟蚜茧蜂的载体植物。     

烟蚜茧蜂寄生对烟蚜生长发育和繁殖的影响

【目的】为探究烟蚜茧蜂Aphidius gifuensis对烟蚜Myzus persicae寄生后烟蚜生长发育和繁殖影响及其在烟蚜防控中的作用。【方法】采用室内叶片培养皿法,测定了不同龄期烟蚜(1-4龄若蚜及成蚜)被烟蚜茧蜂寄生后烟蚜当代(F₀)及后代(F₁)的发育历期、寿命、产仔量。【结果】烟蚜1龄若蚜被烟蚜茧蜂寄生后,1龄若蚜历期受到显著影响,较未被寄生对照缩短了0.65 d (33.00%),而2-4龄若蚜期和成蚜历期未受显著影响; 2龄若蚜被寄生后,4龄若蚜和成蚜历期均受到显著影响,较未被寄生的对照分别缩短了1.50 d (100.00%)和0.83 d (100.00%),而2和3龄若蚜期未受显著影响; 3龄若蚜被寄生后,4龄若蚜和成蚜期均受到显著影响,较未被寄生对照分别缩短了1.50 d (100.00%)和0.83 d (100.00%),而3龄若蚜期未受显著影响。2龄若蚜被寄生后烟蚜的寿命和产仔量均受到显著影响,寿命较未被寄生对照缩短了8.39 d(54.00%),每雌产仔量较未被寄生对照减少了48.67头(100.00%)。...     

A STUDY ON THE RELATIONSHIP BETWEEN THE QUANTITY OF HONEYDEW AND THE rmOF GREEN PEACH APHID

Abstract Experiments were carried out to study the relationship between the quantity of honeydew and r_mof green peach aphid infesting 50 tobacco varieties in the field from 1990 to 1992. The results showed that the range for r_m is from 0.102 to 0.498, for honeydew secreted during 24 hours is 3.862 mm²/aphid to 29. 356 mm²/aphid. It also showed that the resistance of tobacco varieties to green peach aphid manifested in the reduction of net reproductive rate. Both r_m and honeydew had significant relations to the population of green peach aphid in the field, and therefore the quantity of honeydew can be used as an index in determination of tobacco resistance to green peach aphid.     

我国烟蚜种群分化的RAPD分析

用RAPD-PCR技术研究了我国烟草上烟蚜Myzus persicae (Sulzer)的种群分化。结果表明：我国烟蚜的不同地理种群和不同体色之间DNA均呈现出多态性,且不同的引物可在不同水平上反应出烟蚜种群的DNA多态性。Nei的遗传距离表明我国烟草上烟蚜的分化仅在种群水平上,并未达到亚种水平。用相似性指数和Nei的遗传距离对所筛选的三个引物OPX-04、OPX-06和OPX-19的扩增结果进行聚类,虽然二者的结果不一致,但均可反应出烟蚜的地理种群和体色生物型的DNA差异。在DNA水平上,与完全周期生活史的烟蚜相比,完全周期和不完全周期生活史混合发生的烟蚜与不完全周期生活史的烟蚜更为接近,而两种生活史混合发生的烟蚜之间无明显差异。从体色看,红色比黄绿色更接近褐色。     

Elevated CO2 shifts the focus of tobacco plant defences from cucumber mosaic virus to the green peach aphid

Elevation in CO₂ concentration broadly impacts plant physiological characteristics, which influences herbivores and biotrophic pathogens, which in turn regulate the plant defensive response. In this study, responses of tobacco plants to stress in the form of the green peach aphid, Myzus persicae (Sulzer), or cucumber mosaic virus (CMV), or both aphid and CMV combined were investigated in open‐top chambers under ambient and elevated CO₂ concentrations. We measured aboveground biomass and foliar chlorophyll, nitrogen, non‐structural carbohydrates, soluble protein, total amino acid and nicotine content in tobacco plants and also measured aphid population dynamics, body weight, honeydew production and anti‐oxidative enzyme activities in individual aphids. Plants produced more secondary metabolites for defence in both CO₂ treatments when treated with aphid and CMV combined than with either alone. Aphid density significantly increased on CMV‐infected tobacco plants (relative to uninfected plants) under ambient CO₂ but not under elevated CO₂. This suggests that plant defences against virus and aphid would be more efficient under elevated CO₂. Plant defence appears to shift from plant virus to aphid under increasing CO₂ levels, which highlights the potential influences of multiple biotic stressors on plants under elevated CO₂.     

Settling behaviour and reproductive potential of the green peach aphid Myzus persicae on peach varieties and a related wild Prunus

Discovery in the late seventies of resistance to the green peach aphid Myzus persicae (Sulzer) (Homoptera: Aphididae) in Prunus species was based on screening in the field or in greenhouses with natural aphid populations. Here, we assess the impact of these wild and domesticated peach trees on the behaviour, development, reproductive performance and demography of cloned aphids under controlled light and temperature. Four peach varieties, i.e., Rubira, Weeping Flower Peach, Summergrand and Malo konare and the clone P1908 of the related species Prunus davidiana were tested against the highly susceptible cultivar GF305. Besides a variability in the performance of aphids among experiments, our results showed that (i) distinct mechanisms were involved in the sources of resistance studied and (ii) the ranking of the genotypes on their resistance/susceptibility status remained roughly stable throughout the experiments. Observations on the settling behaviour of first instar nymphs demonstrated antixenosis components in the resistance conferred by Rubira and Weeping Flower Peach. Nymphs began to leave the plants after a short exposure (19–21 h) and no aphid was left after 4 days. Nymphal mortality remained rather low (16%) compared to the repellent effect on aphids of both genotypes. Nymphs disappeared from Weeping Flower Peach significantly earlier than from Rubira. Summergrand, Malo konare and P. davidiana clone P1908 were accepted as host plants by aphids. On P. davidiana, decreased fecundity and intrinsic rate of natural increase (rm=0.20, averaged on all experiments) were clear expression of antibiosis. In addition, the mean length of the mature embryos within the gonads of the females on the day of adult moult was negatively correlated with the total number of embryos, providing evidence that aphids on this genotype lacked sufficient ressources to be directed both towards production and growth of embryos. Compared to the most susceptible cultivar GF305 (rm=0.36), Summergrand (rm=0.26) and Malo konare (rm=0.28) had, to a lesser extent, a negative impact on nymph production and rate of increase.     

七星瓢虫和异色瓢虫四变种成虫对茶蚜蜜露的搜索行为和蜜露的组分分析

采用培养皿 ,1承接茶蚜自然分泌蜜露 ;2收集蜜露浓缩后点于培养皿中心。逐头释放瓢虫于分别盛有这 2类蜜露的培养皿中心进行生物测定 ,两个试验均证明 :1蜜露强烈地吸引七星瓢虫和异色瓢虫 ,随着蜜露浓度呈梯度地增大 ,搜寻时间极显著地延长 ( P<0 .0 1 ) ;2蜜露可激发瓢虫的搜索行为由广域搜索型转换为地域集中搜索型。前 0～ 5s局限在较小范围内不断地转向 ,即搜索速度小 ,转动角度大。七星瓢虫和异色瓢虫显明变种最敏感 ,搜索和滞留时间也最长。用高效液相色谱定性定量地分析出蜜露中有茶氨酸等 1 3种氨基酸和蔗糖等 7种糖分。     

Survival, growth, and reproduction of two aphid species on sucrose solutions containing host or non-host honeydews

Aphids, like most phloem-feeding insects, commonly exhibit a high degree of host specificity. Plant-specific chemical compounds are likely to serve as important host selection cues for monophagous aphids and such substances could be present in aphid honeydew. Apterous virginoparae ofMyzus persicae (Sulzer) andPhorodon humuli (Schrank) were reared on a buffered sucrose solution containing various aphid honeydews or a mixture of amino acids. In two separate experiments, the host-specificP. humuli (hop aphid) could grow and reproduce only on diets containing honeydew collected from hop (Humulus lupulus L.).M. persicae (the green peach aphid, GPA) did not perform well on diets containing hop honeydew, perhaps because hop is a poor GPA host. Honeydew collected from preferred GPA host plants rape,Brassica napus L., and jimsonweed,Datura stramonium L., allowed GPA growth and reproduction. Hop aphids, however, performed poorly on rape and jimsonweed honeydew diets. Bell pepper,Capsicum annuum L., honeydew supported neither the hop aphid nor GPA. The study of aphid honeydew components may contribute towards a more complete understanding of host preference and selection phenomena in aphids.     

Olfactory response by the aphidophagous gall midge, Aphidoletes aphidimyza to honeydew from green peach aphid, Myzus persicae

Female adults of the aphidopagous gall midge, Aphidoletes aphidimyza (Rondani) (Diptera: Cecidomyiidae), showed an olfactory response to honeydew excreted by the green peach aphid, Myzus persicae (Sulzer) (Hemiptera: Aphididae) under laboratory conditions. The response was only elicited by treatments with honeydew, whereas aphids, aphids with pepper plants or leaves, and pepper plants or leaves were not attractive to the midges. Dose‐dependent responses were observed from whole honeydew, honeydew volatiles extracted in pentane, and honeydew volatiles captured on Porapak Q®. When honeydew was eluted with three sequential pentane washes, a positive response was only observed from the midges for the first wash. Female midges laid more eggs on pepper plants infested with higher densities of M. persicae. The olfactory response of midges to honeydew is discussed with respect to prey location.     

Females of Cotesia vestalis,a parasitoid of diamondback moth larvae,learn to recognise cues from aphid‐infested plants to exploit honeydew

1. To maximise their reproductive success, the females of most parasitoids must not only forage for hosts but must also find suitable food sources. These may be nectar and pollen from plants, heamolymph from hosts and/or honeydew from homopterous insects such as aphids. 2. Under laboratory conditions, females of Cotesia vestalis, a larval parasitoid of the diamondback moth (Plutella xylostella) which does not feed on host blood, survived significantly longer when held with cruciferous plants infested with non‐host green peach aphids (Myzus persicae) than when held with only uninfested plants. 3. Naïve parasitoids exhibited no preference between aphid‐infested and uninfested plants in a dual‐choice test, but those that had been previously fed aphid honeydew significantly preferred aphid‐infested plants to uninfested ones. 4. These results suggest that parasitoids that do not use aphids as hosts have the potential ability to learn cues from aphid‐infested plants when foraging for food. This flexible foraging behaviour could allow them to increase their lifetime reproductive success.     

Co-localisation of host plant resistance QTLs affecting the performance and feeding behaviour of the aphid Myzus persicae in the peach tree

The architecture and action of quantitative trait loci (QTL) contributing to plant resistance mechanisms against aphids, the largest group of phloem-feeding insects, are not well understood. Comparative mapping of several components of resistance to the green peach aphid (Myzus persicae) was undertaken in Prunus davidiana, a wild species related to peach. An interspecific F(1) population of Prunus persica var. Summergrand × P. davidiana clone P1908 was scored for resistance (aphid colony development and foliar damage) and 17 aphid feeding behaviour traits monitored by means of the electrical penetration graph technique. Seven resistance QTLs were detected, individually explaining 6.1-43.1% of the phenotypic variation. Consistency was shown over several trials. Nine QTLs affecting aphid feeding behaviour were identified. All resistance QTLs except one co-located with QTLs underlying aphid feeding behaviour. A P. davidiana resistance allele at the major QTL was associated with drastic reductions in phloem sap ingestion by aphids, suggesting a phloem-based resistance mechanism. Resistance was also positively correlated with aphid salivation into sieve elements, suggesting an insect response to restore the appropriate conditions for ingestion after phloem occlusion. No significant QTL was found for traits characterising aphid mouthpart activity in plant tissues other than phloem vessels. Two QTLs with effects on aphid feeding behaviour but without effect on resistance were identified. SSR markers linked to the main QTLs involved in resistance are of potential use in marker-assisted selection for aphid resistance. Linking our results with the recent sequencing of the peach genome may help clarify the physiological resistance mechanisms.     

寄主转换对烟蚜种群特征的影响

试验结果表明：除从油菜上转到桃树上不成功外,烟蚜可在昌,油菜和桃树之间的成功转换,且同寄主之间的转换比异寄主之间的转换生殖前期短,产仔量大。烟蚜寄主转换以ｒｍ值的大小依次为桃树转油菜－烟草转油菜－油菜转烟草－桃树转烟草－烟草转桃树。