Suitability Assessment of Mononychellus tanajoa(Acari:Tetranychidae) in Yunnan Based on Maxent Model

[Objective] This study aimed to analyze the potential geography distribution of M.tanajoa in Yunnan.[Method] The suitability of M.tanajoa in Yunnan was studied in this paper using Maxent and ArcGIS,based on the biological data and known distribution of M.tanajoa,and meteorological data from years of 1950-2000 in WorldClim.[Result] The results showed that there were four levels of suitability assessment of M.tanajoa in Yunnan,in which western and eastern areas are in the most suitability,including part areas of Simao,Lincang,Baoshan,Nujiang,Diqing,Qujing and Wenshan areas.[Conclusion] The potential geographic distribution of M.tanajoa in Yunnan defined in this paper constructed the theory basis and technical support for scientifically forming of quarantine policy and measure for M.tanajoa in China.

Effects of High Temperature on Activities of Some Protective Enzymes in Mononychellus tanajoa

[Objective] Mononychellus tanajoa is a mite speices recently invaded into China in 2008. Temperature is one of the most important ecological factors affecting the growth and reproduction of M. tanajoa. The objective of the current study was to reveal the effects of high temperature incubation on the activities of some protective enzymes in M. tanajoa at different growth stages. The results would contribute to the understanding of the adaptable distribution of M. tanajoa after its invasion into China, the mechanisms in its invasion, diffusion and ecological adaptation, and the monitor- ing, early warning and effective prevention of its damage. [Method] Six protective enzymes, Le. polyphenol oxidase （PPO）, peroxidase （POD）, ascorbate oxidase （AsA- POD）, catalase （CAT）, superoxide dismutase （SOD） and esterase （EST）, were cho- sen to study their activities after the mites at different growth stages were incubated at a extremely high temperature of 42 ~C for a certain period of time up to 24 h. The activities were measured by spectrophotometric endpoint assay method. [Results] Enzyme activities in M. tanajoa were affected by the high temperature incubation. However, differences in enzyme activity changes were found among different protec- tive enzymes and among different growth stages of M. tanajoa. Activities of PPO, POD, AsA-POD and CAT were significantly increased in the larval mites and female adult mites of M. tanajoa. CAT activity was significantly decreased in protonymph and deutonymph of M. tanajoa. Activities of PPO, POD and AsA-POD in protonymph and deutonymph showed no obvious difference from the control. [Conclusion] The activity changes of some protective enzymes in M. tanajoa following high-temperature treatment are part of its anti-stress reaction mechanism. In mite protonymph and deutonymph, activities of PPO, POD and AsA-POD are similar to the untreated con- trol which may be associated with the thermostability of M. tanajoa. It is concluded that, the long-time stress of extreme temperature may result in the increase of the thermostability of mite individuals, the enhancement of the population thermal stability and subsequently lead to rapid expansion of the population.

Validation of Molecular Tools for Monitoring the Entomopathogen Neozygites Tanajoae(Entomophthorales:Neozygitaceae) Used for Biological Control of Cassava Green Mite in Africa

Neozygites tanajoae is an entomopathogenic fungus which has been used for biocontrol of the cassava green mite(Mononychellus tanajoa,CGM)in Africa. Establishment and dispersal of Brazilian isolates which have been introduced into some African countries in recent years to improve CGM control was followed with specific PCR assays.Two primer pairs,

木薯单爪螨全球潜在地理分布的MaxEnt预测

木薯单爪螨(Mononychellus tanajoa Bondar)是木薯产区重要的毁灭性害螨之一,是世界上重要的具有检疫意义的有害生物。本文利用MaxEnt软件预测全球范围内气候条件适宜该虫存活的区域,在此基础上结合寄主分布预测了木薯单爪螨的全球潜在地理分布。预测结果显示,在104个木薯种植国家或地区中,除了非洲北部和亚洲部分木薯种植国外,该螨在其余国家或地区的生存适宜值均大于10,为该螨的潜在地理分布区,加强这些区域的调查监测对保护当地木薯种植有重要意义。

卵高温胁迫对木薯单爪螨发育与繁殖的影响研究

为探讨木薯单爪螨的生态适应性机理,揭示其种群扩散蔓延机制,开展了卵高温胁迫对木薯单爪(螨中雌处生性理长百不发分同育率时与)间及繁(后殖0.代5的、成1影、螨2响、寿4研、命8究、。1。6、结将24果木h表薯)后明单置:爪卵于螨高室卵温温在处(2梯5理℃度显)下高著饲温影养(响3,0木观℃薯、察3单3其℃爪卵、3螨孵6℃的化、发率39育、℃发与、育4繁2历℃殖期)人。、工随后气着代候温性度比箱的升高和处理时间的延长,木薯单爪螨的发育历期显著延长,卵孵化率、后代雌性百分率与后代雌成螨热寿高最温命敏处显感理著时下2h间降以。。上因温(此包度,括越卵高2高h,)温对后胁木在迫薯2显5单℃著爪下影螨均响发不木育能薯与孵单繁化爪殖和螨的完的影成生响任长越何发显发育著育与,历尤繁期其殖;对,4从2卵℃而和高可幼温能螨1影h的为响发木木育薯薯;卵单单爪经爪螨螨42种卵℃群的变化。本研究结果可为木薯单爪螨扩散蔓延范围及生态适应性提供理论依据,为科学制定中国针对木薯单爪螨的检疫政策和防控措施,以防其进一步扩散蔓延提供理论依据和前期工作基础。

木薯单爪螨发生与生物防治研究进展

木薯单爪螨是一种严重危害木薯生长和影响木薯产量的害螨,对木薯产业的发展构成较大威胁。本研究归纳了木薯单爪螨在国内外的发生情况,包括传播过程、危害机制、影响单爪螨危害的因子等方面,并重点从生物防治的角度阐述了该螨害的防治研究进展;分析了单爪螨、木薯本身以及环境条件是影响木薯单爪螨危害的三大因素;提出今后可从单爪螨对木薯生理生化特征的影响、木薯单爪螨生物防治的机理如与植物、环境互作的关系、天敌组合等方面进行深入研究。