单对汰选方法在加速抗高效氯氟氰菊酯棉铃虫品系汰选中的应用

通过设计杂合种群单对杂交方式,研究了加速获得抗性品系的方法。以高效氯氟氰菊酯群体汰选后抗性倍数为4.9倍的棉铃虫种群及其同源对照种群为材料,同时设置常规群体汰选方法与单对汰选方法,研究单对汰选方法在加速抗高效氯氟氰菊酯棉铃虫品系汰选中的作用。结果表明,群体汰选两代后抗性倍数由4.9倍提高到7.4倍, 而单对汰选两代后抗性倍数由4.9倍提高到27.3倍。表明在常规群体汰选中穿插几代单对汰选方法可明显加快棉铃虫种群对高效氯氟氰菊酯的抗性汰选进程。     

某些阳离子在大豆胞囊线虫生防系统中的作用

室内测定了不同浓度的 6种阳离子 :钼、硼、锌、铜、锰和铁对大豆胞囊线虫卵的孵化、大豆种子发芽和根系生长 ,以及对线虫生防菌———厚垣轮枝菌菌丝生长的影响。结果发现 ,在供试所有浓度下 ,铜、锰和铁明显抑制大豆胞囊线虫的卵孵化 ,锌具明显刺激作用 ;在供试浓度水平较低时 ,铜、锰和铁对大豆种子发芽及根系生长有轻微抑制 ,锰的抑制较为明显 ,但均不影响进一步发育 ;在供试浓度较低时 ,铜、锰和铁对厚垣轮枝菌菌丝生长无任何影响。铜可作为线虫生防制剂的添加剂。     

十种常用农药与球孢白僵菌的生物学相容性

球孢白僵菌孢子粉与10种常用农药相容性的测定结果显示,随着孢子浓度上升,所试农药对孢子的抑制作用均有不同程度的增强。在1/10田间常规使用浓度下,百菌清和代森锰锌均能抑制或杀死孢子(萌发率<1％)。除阿维菌素外,所有杀虫剂均与白僵菌孢子相容,在常规使用浓度的10倍稀释液中孢子萌发率达90％以上。吡虫啉、蚜虱灵、灭多威和氟虫腈与孢子的相容性最好,其中吡虫啉和蚜虱灵对孢子萌发率的影响不明显随药剂浓度的变化而变化,即使在田间常规使用浓度下孢子萌发率也在95％以上,而阿维菌素与白僵菌的相容性极差。因此,应用白僵菌制剂防治害虫,选择生物学相容性好的农药以低剂量与白僵菌制剂混用,既可使菌剂增效,又可大幅度降低化学药剂用量。     

Pest Management in Traditional Tropical Agroecosystems: Lessons for Pest Prevention Research and Extension

Based on current agroecological theory and IPM practices, this review explores the role of traditional practices, involving site selection, soil management, timing of planting and harvesting, crop resistance, intercropping, weed management, harvest residue management, post-harvest management, natural enemies management, mechanical control, repellents and traps in the natural regulation of potential pests. In synthesis, the literature suggests that although pest management professionals focus their efforts on pest control, the preventative approach taken by traditional farmers is more effective. Potential constraints to the implementation of this preventive pest management approach include:(1) lack of integration of ecological theory and pest management, (2) lack of cooperation among social and biological scientists, and (3) lack of real efforts to work with farmers as equals and support mechanisms that protect their knowledge. This revised version was published online in July 2006 with corrections to the Cover Date.     

Identification of ALS inhibitor‐resistant Amaranthus biotypes using polymerase chain reaction amplification of specific alleles

Summary Polymerase chain reaction (PCR) amplification of specific alleles (PASA) was adapted as a molecular marker‐based method for the rapid detection of point mutations in Amaranthus retroflexus and Amaranthus rudis leading to ALS inhibitor resistance. Two pairs of primers were designed for the specific amplification of alleles of the ALS gene of susceptible and resistant biotypes. The allele‐specific primer matched the desired allele, but mismatched the different allele at its 3′ end. Differentiation was carried out by comparison of the amplified DNA fragments in gel electrophoresis after PASA‐PCR. In A. rudis, differentiation was possible with one PCR and genomic DNA as probe. A ‘nested’ PCR was necessary for the differentiation of sensitive and resistant A. retroflexus. PASA is useful for the identification of resistant weed biotypes and also as a monitoring tool to map resistance occurrence and distribution. Advantages include the fast and clear separation of those plants with and without mutations at an early stage of development, its easy and consistent performance and quick results compared with existing resistance detection tests. These advantages, when combined with management strategies, enable further activities to reduce herbicide resistance.     

双孢蘑菇性亲和性相关分子标记的初步筛选

以传统的形态，生理生化分析和最新的DCS－PDMA性亲和性测定方法为基础， 结合群体分离分析和RAPD技术来源于同一双孢蘑菇异核体菌株的12个不育同核原生质体个体进行分析，筛选与性亲和性相关的分子标记。研究结果表明，供试的12个不育同核原生质体个体被分成两大类性亲和性类型，其中一类（A^ ）包括不育同核原生质体个体B、C、D、E、F、G、H、I、J、L，另一类（A^-）则仅仅包括不育同核原生质体个体K和M，同时筛选到一个与性亲和性相关的分子标记OPA16 1500。从而为间地利用双孢蘑菇本身特有的交配型作标记来指导杂交育种工作和进一步将性亲和性基因定位分离克隆奠定了坚实的基础。     

Olive processing wastes for weed control

The herbicidal effect of olive processing wastes (OPW) on some weed species in wheat, maize and sunflower was investigated in the Aegean region of Turkey. In trials with maize and sunflower, OPW was applied as an air‐dried solid form at 3 and 4.5 kg m^?2. It provided an effectiveness level on Portulaca oleracea of 63–98%. In trials with wheat, OPW was applied as solid and liquid forms, each at two different doses, namely 4.5 and 6 kg m^?2 (solid), and 5 and 10 L m^?2 (liquid). Solid OPW provided a reduction in total weed coverage of 75% and 81% at doses of 4.5 and 6 kg m^?2, respectively. The weed coverage reduction by liquid OPW was 39% and 62% with 5 and 10 L m^?2, respectively. Apart from 12–26% reduction of the number of germinating seeds, OPW showed no toxic effects on maize and sunflower. Wheat was affected in the initial stages but no adverse effect was detected at harvest. It can be concluded that the herbicidal effect of OPW may be considered as an alternative to chemical weed control in some important summer crops (maize and sunflower) and for most of the weeds in winter wheat.     

Seasonal distribution of phytoplasmas in Australian grapevines

The distribution and persistence of phytoplasmas were determined in Australian grapevines. Phytoplasmas could be detected using the polymerase chain reaction (PCR) from shoots, cordons, trunks and roots throughout the year, and phytoplasmas appear to persistently infect Australian grapevines from year to year. Phytoplasmas were not always detected in samples from the same sampling area from one sampling period to the next. Phytoplasma detection by PCR was improved by sampling from shoots, cordons and trunks, especially during October (early spring). The diseases expressed by the 20 grapevines used in the distribution and persistence studies were monitored. Australian grapevine yellows disease (AGY) was expressed by 17/20 grapevines at some time during the study, whilst only 4/20 and 15/20 grapevines expressed restricted growth disease (RG) and late season leaf curl disease (LSLC), respectively. All grapevines with RG and LSLC also had AGY. The three diseases were persistently expressed in some grapevines and remission of disease was observed in others. The results of PCR detection in the same grapevines indicated that phytoplasmas were more frequently detected in AGY-affected grapevines that also expressed RG and LSLC compared with grapevines expressing AGY alone. Phytoplasmas were detected in symptomless plant material but less frequently compared with AGY-affected material.     

我国农药残留快速检测技术的研究与应用现状

本文简述了目前农药残留快速检测技术的研究概况，分析了农药残留快速检测技术在我国的实际应用情况。     

Rapid detection of Phytophthora cinnamomi using PCR with primers derived from the Lpv putative storage protein genes

Phytophthora cinnamomi is an ecologically and economically important pathogen. In this study, PCR assays were developed with primer pair LPV2 or LPV3 for rapid detection and identification of this organism. Both primer pairs were selected from putative storage protein genes. The specificity of these primer pairs was evaluated against 49 isolates of P. cinnamomi , 102 isolates from 30 other Phytophthora spp., 17 isolates from nine Pythium spp. and 43 isolates of other water moulds, bacteria and true fungi. PCR with both primer pairs amplified the DNA from all isolates of P. cinnamomi regardless of origin. The LPV3 primers showed adequate specificity among all other species tested. The LPV2 primers cross-reacted with some species of Pythium and true fungi, but not with any other Phytophthora species. PCR with the LPV3 primers detected the pathogen at levels of a single chlamydospore or 10 zoospores in repeated tests. The PCR assay was at least 10 times more sensitive than the plating method for detection of the pathogen from artificially infested soilless medium, and, to a lesser extent, from naturally infected plants. PCR with LPV3 primers can be a useful tool for detecting P. cinnamomi from soilless media and plant tissues at ornamental nurseries, whereas the LPV2 primers can be an effective alternative for identification of this species from pure culture. Applications of these assays for detection of P. cinnamomi in other environments were also discussed.