抗感吡虫啉褐飞虱在抗虫水稻品种上的适合度比较

建立抗呲虫啉褐飞虱Nilaparvata lugens(St(a)l)种群和敏感呲虫啉褐飞虱种群在不同抗虫水稻品种(TN1、IR36)上的实验种群生命表,比较了抗感吡虫啉种群在感虫品种TN1上以及在抗虫品种IR36上饲养4代的种群趋势指数(Ⅰ)和适合度的差异.结果表明,在TN1上,抗呲虫啉和敏感吡虫啉褐飞虱种群的种群数...     

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     

不同地理种群褐飞虱的抗逆性

研究了不同地理种群褐飞虱对水稻抗性品种、若虫高密度、高温、饥饿和杀虫剂等逆境条件的抗性。结果表明,广西和云南种群褐飞虱对抗虫品种的适应性比浙江种群强而广,浙江种群只能适应抗虫品种ＩＲ２６而广西和云南种群则还能适应抗性更高的ＡＳＤ７和Ｒａｔｈｕ Ｈｅｅｎａｔｉ。广西和云南种群较能适应高密度环境,而浙江种群的适应性较差,其雌虫短翅率与若虫密度呈显著负相关。虽然广西和云南种群对高温的忍受性比浙江种群的强     

褐飞虱对五种杀虫剂抗性的快速检测技术

【目的】建立褐飞虱Nilaparvata lugens对常用杀虫剂抗性的快速检测技术,实时掌握田间褐飞虱种群的抗药性水平,以指导褐飞虱防控合理用药。【方法】基于玻璃瓶药膜法,研制褐飞虱3龄若虫对吡虫啉、啶虫脒、醚菊酯、毒死蜱和异丙威5种杀虫剂抗性的快速检测试剂盒;利用试剂盒测定的死亡率与稻苗浸渍法测得的抗性倍数进行相关性分析,并验证利用试剂盒快速测定褐飞虱田间种群对5种杀虫剂 抗性水平的准确性。【结果】处理1 h时吡虫啉、啶虫脒、醚菊酯、毒死蜱和异丙威对褐飞虱室内敏感种群3龄若虫的LD₉₀分别为：30.96, 92.05, 117.24, 514.21和1.24 ng/cm²。在吡虫啉、啶虫脒、醚菊酯、毒死蜱和异丙威相应诊断剂量下,贵州省不同田间种群褐飞虱3龄若虫的校正死亡率分别在23.75%~78.75%, 25.00%~78.75%, 43.75%~88.75%, 36.25%~85.00%和18.75%~67.50%之间。相关性分析表明,上述田间种群褐飞虱3龄若虫的死亡率与稻苗浸渍法测定的抗性倍数呈显著负相关,相关系数在0.8751~0.9754之间。通过快速检测试剂盒获得的死亡率及相关性方程计算得到贵州安龙地区(AL)褐飞虱种群对吡虫啉、啶虫脒、醚菊酯、毒死蜱和异丙威的推测抗性倍数分别为7.23, 3.68, 4.14, 4.12和31.18,采用稻苗浸渍法测得上述5种杀虫剂的实测抗性倍数分别为6.33, 5.24, 3.71, 4.50和26.56,表明推测抗性倍数与实测的抗性倍数结果表现一致。【结论】该快速检测试剂盒可以通过测定褐飞虱田间种群的死亡率,快速评估褐飞虱田间种群对杀虫剂的抗性水平。     

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。     

贵州稻区褐飞虱种群对六种杀虫剂的抗性动态

【目的】为明确贵州褐飞虱Nilaparvata lugens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2013-2015年采自贵州黄平、桐梓和开阳3地的褐飞虱种群对6种杀虫剂(吡虫啉、噻虫嗪、异丙威、噻虫胺、啶虫脒和醚菊酯)的抗性。【结果】贵州褐飞虱种群对不同的杀虫剂存在着抗性差异。与敏感品系相比,2013-2015年间3地田间褐飞虱种群对吡虫啉、噻虫嗪、异丙威、噻虫胺的抗性均达到中等水平抗性,抗性倍数(resistance ratio,RR)分别为21.88~95.38,10.91~69.36,13.00~57.23和23.11~39.54倍;而对啶虫脒和醚菊酯仍处于敏感阶段,RR分别为0.47~0.75和0.41~0.85倍。【结论】褐飞虱对吡虫啉和噻虫嗪的抗性较高,可能与近年来广泛地大量使用有关。本研究的抗性动态监测结果对贵州稻区褐飞虱的杀虫剂种类调整及施药策略等具有重要指导作用。     

褐飞虱对吡虫啉的抗性机理和靶标分子毒理学

褐飞虱Nilaparvata lugens是水稻最重要的害虫之一,长期依赖化学防治导致了该害虫对不同类型杀虫剂抗性的产生,对新烟碱类杀虫剂吡虫啉高水平抗性的产生更是造成了巨大的粮食生产损失。近年来在褐飞虱对吡虫啉抗性机理,以及在抗药性机理研究推动下吡虫啉作用靶标褐飞虱神经系统烟碱型乙酰胆碱受体（nicotinic acetylcholine receptors, nAChRs）毒理学等方面取得了许多研究进展。nAChRs是昆虫神经系统中最重要的神经递质受体,是几类重要杀虫剂的作用靶标,其中以新烟碱类杀虫剂为代表。通过对比敏感品系和室内连续筛选获得的高抗吡虫啉品系,在褐飞虱两个nAChRs亚基Nlα1和Nlα3中均发现了抗性相关点突变Y151S,该突变导致了受体与吡虫啉结合亲和力的显著下降,而对内源神经递质乙酰胆碱的亲和力影响很小。Nlα1与褐飞虱另外两个亚基Nlα2和Nlβ1共聚成一个受体,构成吡虫啉低亲和力结合位点;Nlα3与褐飞虱另外两个亚基Nlα8和Nlβ1共聚成一个受体,构成吡虫啉高亲和力结合位点。不仅褐飞虱nAChRs与吡虫啉抗性相关,某些nAChRs附属蛋白也直接影响褐飞虱对吡虫啉的抗性,如Lynx蛋白。关于褐飞虱nAChRs组成、抗药性相关变异、受体附属蛋白对抗药性的影响等方面的研究,均为国内外前沿报道,不仅有助于对新烟碱类杀虫剂抗性机理的理解,对昆虫nAChRs毒理学同样具有很大的推动作用。     

华中地区五种水稻品种对褐飞虱生活史和种群动态的影响

【目的】通过研究华中地区5种主栽水稻品种对褐飞虱Nilaparvata lugens (St?l)生活史和种群动态的影响,评价褐飞虱个体和种群对5种水稻品种的取食适应性特征,为华中地区主栽水稻的应用推广和褐飞虱的防控提供数据参考。【方法】利用两性生命表理论,研究华中地区5种水稻("深两优3117"、"金优957"、"齐两优908"、"丰优989"、"汕优63")对褐飞虱生活史参数的影响,并用软件模拟5种水稻喂饲下褐飞虱种群动态发生情况。【结果】不同水稻品种对褐飞虱4-5龄若虫的影响最大,取食"齐两优908"后褐飞虱发育历期较其他水稻品种显著延迟(P0.05);"汕优63"和"金优957"饲喂下的褐飞虱产卵量显著低于其它3种水稻品种(P0.05);"齐两优908"喂饲处理下,褐飞虱成活率较其他4种水稻品种显著降低(P 0.05)。褐飞虱在5种水稻品的净增值率(R0)由高到低依次为"丰优989""深两优3117""汕优63""金优957""齐两优908"。【结论】华中地区5种主栽水稻品种,"齐两优908"对褐飞虱成活率具有显著的降低效果;褐飞虱取食"丰优989"和"深两优3117"后种群净增值率最高。     

杀虫剂胁迫下褐飞虱迁飞虫和本地虫后代体内粗脂肪、可溶性糖及氨基酸含量的比较

为了解迁飞种群与居留种群后代发生再猖獗的生理生化差异,探讨再猖獗的机制,比较研究了在两个水稻品种（TN1和协优963）上施用杀虫剂后褐飞虱Nilaparvata lugens (Stål)迁飞虫和本地虫后代3龄、5龄若虫和成虫体内可溶性糖和粗脂肪含量以及迁飞成虫与其后代成虫体内游离氨基酸含量的变化。结果表明： 施药以及未施药处理(对照)TN1水稻品种上的迁飞后代3龄、5龄若虫和成虫体内的可溶性糖含量均显著高于本地虫。与可溶性糖含量相比,施药以及对照TN1水稻品种上的迁飞后代3龄、5龄若虫和成虫体内的粗脂肪含量均显著低于本地虫。协优963上3龄、5龄若虫体内可溶性糖含量的变化趋势与TN1上相同。对照水稻上迁飞成虫的粗脂肪含量显著高于本地种群,迁飞与本地3龄、5龄若虫间粗脂肪含量没有显著差异。杀虫剂处理后的水稻上迁飞后代5龄若虫和成虫体内粗脂肪含量显著高于本地虫。方差分析结果也显示,可溶性糖和粗脂肪含量的变化在虫源和杀虫剂,虫源和杀虫剂浓度以及杀虫剂类型和浓度方面有显著交互作用。两种水稻品种上,迁飞当代成虫体内的游离氨基酸含量显著低于其后代成虫。在经3种杀虫剂处理后,TN1上施用三唑磷后成虫体内的氨基酸含量显著高于施用溴氰菊酯和吡虫啉的处理,而协优963上施用溴氰菊酯和吡虫啉显著高于施用三唑磷的处理。本研究结果对深入阐明农药诱导褐飞虱再猖獗的机制具有参考价值。     

湖北稻区褐飞虱田间种群对常用杀虫剂抗药性监测

【目的】明确目前褐飞虱Nilaparvata lugens田间种群对常用防治药剂的抗性现状,为制定褐飞虱的科学用药策略提供科学依据。【方法】于2009-2014年采用稻茎浸渍法监测了湖北褐飞虱武穴梅川、枣阳十里铺、孝感陈店、鄂州长港和武汉江夏稻田的褐飞虱田间种群对11种杀虫剂的敏感性。【结果】湖北稻区褐飞虱田间种群已对吡虫啉(抗性倍数RR=101.8~1 239.4)、噻嗪酮(RR=15.9~1 326.3)产生高水平抗性;对噻虫嗪(RR=24.9~146.5)产生中等水平至高水平抗性;对噻虫胺(RR=9.9~16.5)、呋虫胺(RR=13.5~15.9)、乙虫腈(RR=18.3~60.4)、毒死蜱(RR=17.4~29.8)、异丙威(RR=13.9~46.0)产生中等水平抗性;对啶虫脒(RR=5.1~9.9)产生低水平抗性;对噻虫啉(RR=3.9~7.1)处于敏感至低水平抗性水平;对醚菊酯(RR=1.3~4.9)处于敏感水平。此外,褐飞虱对噻虫嗪、噻嗪酮抗性上升明显,同时褐飞虱对吡虫啉抗性也有上升的趋势。【结论】仍需暂停吡虫啉、噻嗪酮在水稻上防治稻飞虱,严格限制吡蚜酮在水稻上的使用次数;醚菊酯可作为吡虫啉、噻嗪酮和吡蚜酮的替代药剂或轮换药剂。     

种群生存力分析（PVA）的方法与应用

随着人们对资源的加速利用,生境丧失和破碎化导致物种濒危问题日益严重.以岛屿生物地理学为理论起源的种群生存力分析（PVA）,通过分析和模拟种群动态过程并建立灭绝概率与种群数量之间的关系,为濒危物种保护提供了重要的理论依据和研究途径.在过去的几十年中,种群生存力分析已成为保护生物学中一项重要的研究内容.目前种群生存力分析发展稳定,但对其实际预测能力和准确性尚存质疑,应用方面也有待进一步发展.种群生存力分析的进一步完善还需要在理论和方法上的创新,特别是籍于景观生态学和可持续性科学的理念,将空间分析手段、经济社会因素纳入到物种和种群的预测和管理上,从而使其 具有更完整的理论基础和更高的实用价值.为此,本文对种群生存力分析的历史、基本概念、研究方法、模型应用和准确性进行了综述,并提出了有关的研究展望.     

Population structure,population history and DNA barcoding of fruit fly Bactrocera latifrons (Hendel) (Diptera: Tephritidae)

The fruit fly Bactrocera latifrons (Hendel) is an important pest of commercially significant plants such as chili, tomato and eggplant. The species is native to South and Southeast Asia, but has now invaded Japan, Hawaii and Africa. In this study, mitochondrial DNA sequences were used to infer genetic structure and demographic history of B. latifrons. The efficiency of DNA barcodes for identification of B. latifrons was also tested. Ninety‐three specimens infesting four host‐plant species were obtained from 11 sampling locations in Thailand. The mitochondrial haplotype network revealed no major divergent lineage, which was consistent with a phylogenetic analysis that found strong support for the monophyly of B. latifrons. Population pairwise F_ST revealed that most (65%) comparisons were not significantly different, suggesting a high rate of gene flow. Analysis of molecular variance (amova ) found no significant genetic differentiation among populations from different host‐plant species. Sharing of several haplotypes among flies from different host‐plants indicates that the flies were moved freely across the plant species. Demographic history analysis revealed that the population has undergone recent expansion dating back to the end of the last glaciation. Thus, the results indicate that both ongoing and historical factors have played important roles in determining the genetic structure and diversity of B. latifrons. DNA barcoding analysis revealed that B. latifrons specimens were clearly differentiated from other species with 100% correct identification. Therefore, cytochrome oxidase I (COI) barcoding sequences could be effectively used to identify this important pest species, which could encourage monitoring and control efforts for this species.     

龟纹瓢虫广东种群和北京种群的耐热性比较研究

本文以龟纹瓢虫Propylea japonica (Thunberg)的广东和北京两地区种群为材料,对其进行了在不同温度（26℃～36℃）下的发育历期、存活率、种群性比、产卵量的试验观察及对蛹重、幼虫致死高温、亚致死高温预处理、可溶性蛋白质含量的测定等。结果显示：（1）34℃以上温度对两种群龟纹瓢虫的各世代历期均产生了不同程度的影响。广东种群,34℃下的4龄幼虫、成虫产卵前期和世代历期开始延长,在36℃时除1龄幼虫和蛹外,其它虫态的发育历期均比34℃时的显著延长;北京种群,在36℃时,2龄和4龄幼虫的发育历期开始表现为显著延长。雄性比例,在26℃～36℃范围内随着温度上升而增大,至36℃时,两种群成虫均为雄性。从产卵量看,两种群在34℃下急剧下降。（2）在供试条件下,两种群各龄期的存活率,在36℃下开始明显下降,其中对低龄幼虫和卵期影响最大。广东种群卵的孵化率从26℃时的64.3%下降到34℃时的42.3%, 36℃下的则降为20.7%,下降了67.8％;北京种群卵的孵化率从26℃处理的58.0%, 下降到34℃处理的44%,36℃处理仅为12.3%,下降了78.8％。（3）广东种群和北京种群各龄幼虫致死温度相同,分别为1、2龄幼虫44℃、3龄幼虫45℃、4龄幼虫46℃。经39℃亚致死高温预处理150 min后,广东种群和北京种群4龄幼虫在46℃下的存活率分别提高了72%和43.5%。（4）在26℃～34℃之间,随着温度的上升,成虫和4龄幼虫体内可溶性蛋白的含量上升。在常温下生长的4龄幼虫和成虫经39℃、41℃和43℃热激1 h后,4龄幼虫体内可溶性蛋白含量上升,成虫体内可溶性蛋白含量却下降。广东种群4龄幼虫和成虫经39℃热激后可溶性蛋白含量最高,而北京种群经43℃热激后含量最高。本文结果初步明确了龟纹瓢虫对较高温度的忍耐性,发现在36℃下龟纹瓢虫广东种群和北京种群的生长发育和繁殖会受到严重阻碍,对其发育历期、性比、产卵量、存活率等均有不良影响;广东种群和北京种群在31℃下3龄幼虫的发育历期、36℃下世代存活率、经过亚致死高温预处理后的耐热性、热激后虫体内蛋白含量等均存在显著差异。, -bidi-font-family: 'Times New Roman'; mso-bidi-font-size: 12.0pt; mso-font-kerning: 1.0pt; mso-ansi-language: EN-US; mso-fareast-language: ZH-CN; mso-bidi-language: AR-SA">热激1 h后,4龄幼虫体内可溶性蛋白含量上升,成虫体内可溶性蛋白含量却下降。广东种群4龄幼虫和成虫经39℃热激后可溶性蛋白含量最高,而北京种群经43℃热激后含量最高。本文结果初步明确了龟纹瓢虫对较高温度的忍耐性,发现在36℃下龟纹瓢虫广东种群和北京种群的生长发育和繁殖会受到严重阻碍,对其发育历期、性比、产卵量、存活率等均有不良影响;广东种群和北京种群在31℃下3龄幼虫的发育历期、36℃下世代存活率、经过亚致死高温预处理后的耐热性、热激后虫体内蛋白含量等均存在显著差异。, -bidi-font-size: 12.0pt; mso-font-kerning: 1.0pt; mso-ansi-language: EN-US; mso-fareast-language: ZH-CN; mso-bidi-language: AR-SA; mso: 'Times New Roman'">热激1 h后,4龄幼虫体内可溶性蛋白含量上升,成虫体内可溶性蛋白含量却下降。广东种群4龄幼虫和成虫经39℃热激后可溶性蛋白含量最高,而北京种群经43℃热激后含量最高。本文结果初步明确了龟纹瓢虫对较高温度的忍耐性,发现在36℃下龟纹瓢虫广东种群和北京种群的生长发育和繁殖会受到严重阻碍,对其发育历期、性比、产卵量、存活率等均有不良影响;广东种群和北京种群在31℃下3龄幼虫的发育历期、36℃下世代存活率、经过亚致死高温预处理后的耐热性、热激后虫体内蛋白含量等均存在显著差异。, -bidi-font-family: 'Times New Roman'; mso-bidi-font-size: 12.0pt; mso-font-kerning: 1.0pt; mso-ansi-language: EN-US; mso-fareast-language: ZH-CN; mso-bidi-language: AR-SA">热激1 h后,4龄幼虫体内可溶性蛋白含量上升,成虫体内可溶性蛋白含量却下降。广东种群4龄幼虫和成虫经39℃热激后可溶性蛋白含量最高,而北京种群经43℃热激后含量最高。本文结果初步明确了龟纹瓢虫对较高温度的忍耐性,发现在36℃下龟纹瓢虫广东种群和北京种群的生长发育和繁殖会受到严重阻碍,对其发育历期、性比、产卵量、存活率等均有不良影响;广东种群和北京种群在31℃下3龄幼虫的发育历期、36℃下世代存活率、经过亚致死高温预处理后的耐热性、热激后虫体内蛋白含量等均存在显著差异。     

Population dynamics of hypolimnetic rotifers in the Pluss-see (North Germany)

The hypolimnetic rotifer populations of the Pluss-see (Keratella hiemalis, Filinia terminalis, Filinia hofmanni) show similar patterns of changing population parameters indicating that they respond to particular environmental signals in the same way.     

Seasonal population dynamics of Paraquimpevia tenevvima (Linstow) (Nematoda) in the European eel Anguilla anguilla (Linnaeus) in three localities of southwest England

Seasonal population dynamics of Puraquzmperia tenerrima (Linstow) in the European eel Anguillu anguillu (Linnaeus) have been investigated in three localities in Devon, southwest England. The nematode is common and exhibits very similar seasonal patterns in changes of prevalence and abundance in the three localities. The population increases over winter through to late spring or early summer as the recruitment of the new generation occurs throughout this period. Reproduction of the nematode starts in spring. A sharp decrease of prevalence and abundance accompanies or follows reproduction, and infection levels are very low in autumn and early winter. The dispersion pattern of the nematode varies with the infection levels from over-dispersion in spring and early summer to almost random dispersion in autumn and winter. It is suggested that P. tenerrimu is a common specific parasite of eels, especially in small streams or rivers and that insect larvae or species of crustaceans might serve as intermediate hosts for the nematode.     

Population genetics of the diamondback terrapin (Malaclemys terrapin)

We examined the population genetic structure of the diamondback terrapins (Malaclemys terrapin), within and among estuaries. Based on mark-recapture studies, these estuarine turtles have high site fidelity that is likely to make them vulnerable to local extinctions. We tested if observed site fidelity of adults would be reflected in intraestuarine population genetic structure of six highly polymorphic microsatellite loci (five tetranucleotide and one dinucleotide). No evidence was found for population structuring within the Charleston estuary nor among three different estuaries in South Carolina. We then examined four other terrapin populations from North Carolina to New York, as well as from the Florida Keys and from Texas. With increasing geographical distance, genetic differentiation increased from South Carolina through New York, but overall values were low. The dinucleotide locus contributed significantly more to the genetic differentiation of some population comparisons than any of the other loci. Interestingly, terrapins from South Carolina to New York were much more genetically similar to those from Texas (rho = 0.154) than to those from Florida (rho = 0.357). We attribute this pattern to extensive translocations of terrapins during the early 20th century to replenish diminished populations and to provide turtle farms with stocks. Terrapins collected in Texas were especially sought for shipment to the northeastern US because of their larger size. Our study indicates no population structure within or among adjacent estuaries. Thus, the mark-recapture information from adult and subadult feeding locations is a poor predictor of population genetic structure. Additionally, it appears that past human activities may have drastically altered the genetics of current populations. Finally, our data suggest that translocation of eggs or head starting of terrapins within estuaries or among adjacent estuaries is acceptable from a genetic standpoint.     

An Evaluation of Sex-Age-Kill (SAK) Model Performance

ABSTRACT The sex-age-kill (SAK) model is widely used to estimate abundance of harvested large mammals, including white-tailed deer (Odocoileus virginianus). Despite a long history of use, few formal evaluations of SAK performance exist. We investigated how violations of the stable age distribution and stationary population assumption, changes to male or female harvest, stochastic effects (i.e., random fluctuations in recruitment and survival), and sampling efforts influenced SAK estimation. When the simulated population had a stable age distribution and λ > 1, the SAK model underestimated abundance. Conversely, when λ < 1, the SAK overestimated abundance. When changes to male harvest were introduced, SAK estimates were opposite the true population trend. In contrast, SAK estimates were robust to changes in female harvest rates. Stochastic effects caused SAK estimates to fluctuate about their equilibrium abundance, but the effect dampened as the size of the surveyed population increased. When we considered both stochastic effects and sampling error at a deer management unit scale the resultant abundance estimates were within ±121.9% of the true population level 95% of the time. These combined results demonstrate extreme sensitivity to model violations and scale of analysis. Without changes to model formulation, the SAK model will be biased when λ ≠ 1. Furthermore, any factor that alters the male harvest rate, such as changes to regulations or changes in hunter attitudes, will bias population estimates. Sex-age-kill estimates may be precise at large spatial scales, such as the state level, but less so at the individual management unit level. Alternative models, such as statistical age-at-harvest models, which require similar data types, might allow for more robust, broad-scale demographic assessments.     

The influence of soil type and moisture on pupal survival of Bactrocera tryoni (Froggatt) (Diptera: Tephritidae)

Abstract  Larvae of the Queensland fruit fly, Bactrocera tryoni , pupate in the soil, but the influence of soil variables on B. tryoni pupal mortality is not known. For other tropical tephritid species, soil moisture has been identified as a major pupal mortality factor. In the laboratory, we tested the effects of soil moisture and soil type on pupal survival through a factorial experiment which used three soil types (loamy sand, loam, sandy clay) and seven soil moisture levels (0%, 10%, 25%, 50%, 75%, 90% and 100%). Minor, but significant, differences in pupal mortality were observed between the soil types, but the most significant factor affecting pupae was extremes of soil moisture. Eighty-five percent pupal mortality occurred at 0% soil moisture and 30% mortality at 100% soil moisture: very low levels of mortality occurred at all intermediate levels. We detected a significant interaction between soil type and moisture level but cannot explain it. In a follow-up experiment, we demonstrated that prepupal wandering larvae of B. tryoni could discriminate between different moisture levels, with significantly greater pupation in loam soil at 75% soil moisture than at either 0% or 100% soil moisture. Results are used to modify a pupal mortality/soil moisture equation used in a recently published DYMEX model of B. tryoni population dynamics .     

甜菜夜蛾对虫酰肼抗性的生化机制

为了解甜菜夜蛾Spodoptera exigua (Hübner)对虫酰肼的抗性生化机制, 采用活体测定法测定了甜菜夜蛾虫酰肼敏感种群、汰选种群和武汉自然种群体内解毒酶［羧酸酯酶（CarE）和谷胱甘肽-S-转移酶（GSTs)］、保护酶［过氧化氢酶(CAT)、 过氧化物酶（POD）和超氧化物歧化酶（SOD) ］以及与表皮形成相关的表皮酚氧化酶(PO)和几丁质酶的活性。结果表明: 汰选种群和自然种群CarE比活力分别是敏感种群的1.20和2.67倍, GSTs比活力分别是敏感种群的2.34和0.96倍。汰选种群CarE的Km值与敏感种群相比差异显著, 但V_max值无明显差异; 自然种群Km值和V_max值与敏感种群、汰选种群均存在极显著差异。酯酶同工酶电泳酶谱在迁移率、谱带数目、酶带染色深浅等方面均存在明显差异, 分析结果与CarE活力测定、酶动力学研究结果相符。与敏感种群相比, 汰选种群CAT和POD比活力差异不显著, SOD比活力显著增高; 自然种群3种酶比活力均显著增高; 自然种群和汰选种群均是SOD酶活力的变化较CAT和POD明显。汰选种群PO和几丁质酶比活力比敏感种群分别上升了37.64%和27.37%, 自然种群比活力分别上升了59.63%和60.29%。自然种群和汰选种群PO酶动力学常数均与敏感种群存在显著差异。     

Spatio-temporal population genetics of the Danish pine marten (Martes martes)

A spatio-temporal study of genetic variation in the Danish pine marten ( Martes martes ) populations from the Jutland peninsula and from the island of Sealand was performed using 11 microsatellite markers. Samples obtained from 1892 to 2003 were subdivided into historical (prior to 1970) and recent (from 1970) groups. As compared with the historical samples, there was a significant loss of genetic variation in the recent Jutland population, but not in Sealand. Effective population sizes were estimated using Bayesian-based software (TMVP). Historical effective population sizes were 5897 (90% highest probability density, HPD, limits: 1502–6849) in Jutland and 1300 (90% HPD limits: 224–5929) in Sealand, whereas recent effective population sizes were 14.7 (90% HPD limits: 10.9–23.5) in Jutland and 802 (90% HPD limits: 51.8–5510) in Sealand. Significant genetic differentiation ( F _ST) was found between the two historical samples, between the two recent samples, and between the historical and the recent sample in Jutland; whereas the F _ST value between the historical and the recent sample in Sealand was not significant. The significant genetic differentiation between the historical and the recent samples indicates changes in the genetic compositions over time, and the higher F _ST values between the two recent samples, as compared with the two historical samples, indicates that the populations in Sealand and Jutland have drifted apart within a short time span. No deviation from Hardy–Weinberg equilibrium was found within populations, indicating no further substructuring.  © 2008 The Linnean Society of London, Biological Journal of the Linnean Society , 2008, 93 , 457–464.