柞树白粉病传染规律及防治的研究

 柞树白粉病是柞树的主要病害,在我国的大部分有柞林的省份都有发生和危害,严重的影响柞树的生长发育和放养柞蚕。1977~1980年,我们对此病的病原菌的生物学特性和传染规律及防治方法等进行了研究。本文报道的是病原菌形态观察、传染规律及其与环境条件和树种的关系、对柞树生长和养柞蚕的影响及有效的防治方法:6月下旬~7月上旬,往柞树上喷布0.05~0.1%浓度的霉锈净或甲菌定,大面积防治效果分别达到78.4~92.5%和75.5~87.5%,对柞树和柞蚕无药害。     

黄土高原地区冬、春小麦对气候变化的适应度评价

以整个黄土高原地区为研究区域,建立作物的气候变化适应度模型,通过数理统计和地理空间分析方法,分析了自1960—2011年来,区域冬、春小麦对水分、温度、光照的适应度时空变化特征,并进行了适应度分区。结果表明：区域冬小麦全生育期的综合适应度达到了较强适应水平,有减小趋势;除返青—拔节期在中度适应水平外,其他生育期均为较强适应水平。春小麦全生育期的综合适应达到较强适应水平,有升高趋势;灌浆—成熟期最大,达到了较强适应水平;播种—出苗期最小,只达到中度适应水平。区域综合适应度由西北向东南呈增加趋势且与水分适应度分布的相关性最大,与温度适应度的相关性相对较小,与日照适应度的空间分布呈负相关;其倾向率在西部、西北和东北地区呈增加趋势;在南部和东南部呈减少趋势。冬小麦在返青—拔节期,春小麦在播种—出苗期需要加强人工管理,以增强其适应度;且气候变化对北部的春麦种植较为有利,而对南部的冬麦种植不利。     

天山不同海拔雪岭云杉径向生长对气候变化的响应

为研究不同海拔雪岭云杉(Picea schrenkiana)径向生长对气候要素的响应关系,分别在新疆伊犁尼勒克喀什河流域森林低、中、高海拔采集雪岭云杉树芯样本,建立不同海拔雪岭云杉树轮宽度年表。树轮年表与气象资料相关分析结果显示:影响3个采样点树木径向生长的气候因子主要是平均气温和相对湿度,对降水响应微弱。高、低海拔树轮径向生长对气温和相对湿度的响应相同,均对气温正响应,与相对湿度负响应,中海拔则与高低海拔相反。自1991年研究区气候突变后,雪岭云杉径向生长发生“生长分异”,高、低海拔树轮宽度指数呈显著下降,而中海拔呈显著上升。气候突变点前后,树木径向生长主要对气温和相对湿度响应关系不稳定,中海拔对5—9月的气温的正相关和对相对湿度的负相关显著增强,而低、高海拔主要与7—8月的气温转为显著负相关,与1—2月、7—8月相对湿度的正相关显著加强。根据雪岭云杉对气候要素的响应模式,气温的快速升温会加快水分蒸发,相对湿度随之下降,从而引起的干旱加剧对低、高海拔林区雪岭云杉生长产生负面影响,而适宜的增温可能对森林中部雪岭云杉生长具有促进作用。     

Insecticide resistance in Egyptian populations of the cotton whitefly,Bemisia tabaci (Hemiptera: Aleyrodidae)

Three collections of Bemisia tabaci were taken from cotton and vegetable crops at the beginning of the growing season in Egypt. These displayed marked resistance to the carbamates carbosulfan (ca 20- to 50-fold) and aldicarb (ca 40- to 80-fold) and moderate resistance to the pyrethroids cypermethrin (ca 10- to 30-fold) and lambda-cyhalothrin (ca 10- to 25-fold). They displayed no resistance to the organophosphates profenofos and pirimiphos-methyl, or to imidacloprid. Another population, collected at the end of the growing season, differed markedly in its response. In this population, resistance to carbosulfan remained high (ca 40-fold), resistance to profenofos and cypermethrin was increased (ca 20- and 50-fold respectively) and a slight resistance to imidacloprid was detected (ca 6-fold). Resistance to cypermethrin and profenofos was shown to be similar among adults and nymphs. Irrespective of collection date, none of the populations showed resistance to pyriproxyfen. These Egyptian populations were compared with two representative Israeli populations. The differences between their resistance profiles is discussed in terms of their collection date, their geographical proximity and the patterns of insecticide use at their sites of collection.     

我国北方农业旱灾的危害特点与减灾对策

总结了建国后50 a我国北方15省区的农业旱灾危害特点,并分析了旱灾对农、林、牧业的主要危害,提出我国北方通过提高灌溉工程效益,有计划扩大灌溉面积、发展灌溉节水农业、合理调整农业生产结构和布局、强化旱作农业新技术的研究与应用、建立抗旱服务体系、重视旱灾监测预警系统建设等的减灾对策与措施。     

西辽河断流问题及解决对策

西辽河断流的发生具有周期规律性,90年代后期进入新的断流高峰,断流发生的频率和持续的时间较之前周期有所增加,而且有继续断流的趋势,形势严峻。断流不仅引起一系列生态和环境问题,还严重制约流域经济社会发展。通过分析发现,西辽河断流与支流断流有密切联系,流域降水减少、水利工程拦截和社会经济用水增加都是断流的重要原因。并提出从四个方面缓解断流的对策:加强水源地保护,减少支流断流;合理调度水库,强化流域管理;调整产业结构,提高用水效率;开辟新水源,提高水资源的再生能力。     

Q‐collect: results of a European Union project to improve the status of reference collections important for plant health

The ability of National Plant Protection Organizations (NPPOs) and their affiliated laboratories to quickly and reliably detect and identify organisms is critical for the effective performance of phytosanitary measures. Plant pest diagnostics is also essential to support the phytosanitary certification of consignments of plants and plant products exported from the EU. Access to reference material has been identified as a limitation on the ability of laboratories to develop and validate diagnostic tests and ensure the reliability of diagnostics. The EU FP7 Q‐collect project worked to establish the state of the art of current phytosanitary collections, to identify gaps and propose minimum quality standards, to facilitate access to specimens and to design and build networks of reference collections. The main results of the project are presented in this paper.     

Working with the horticultural industry to limit invasion risks: the Swiss experience

Building relationships with stakeholders involved in species introductions is increasingly considered as an effective means to mitigate invasion risks. The horticultural industry is of particular importance to the regulation of alien plants. This paper presents the initial experiences with a recently implemented environmental policy called ‘Duty to Inform’ which aims to limit the risk of plant invasions through alien horticultural plants in Switzerland. The Duty to Inform requires horticulturalists to inform their customers about risks of black‐listed plants and watch list plants. In a joint effort with the Swiss horticultural industry and Swiss authorities, the authors examined customers’ acceptance of plant labels as a means to supply information, and horticulturalists’ attitudes towards the Duty to Inform regulation, and their willingness to act pro‐environmentally. Plant labels were found to be an effective means to inform customers about plant invasion risks and appropriate handling of risk species. The results indicate that among Swiss horticulturalists the awareness of the invasive species problem and the willingness to act is high. Horticulturalists had positive attitudes towards the Duty to Inform regulation and other actions to reduce invasion risks. The authors suggest that these positive attitudes might stem from an active participation of horticulturalists in the development of invasive species regulations in Switzerland.     

灰飞虱对几种杀虫剂的抗性

采用稻苗浸渍法测定了灰飞虱对7种常用杀虫剂的抗性。2011年监测了我国江苏、浙江、安徽三省9个灰飞虱种群对噻虫嗪、烯啶虫胺、毒死蜱、吡蚜酮、噻嗪酮、高效氯氰菊酯及氟虫腈的抗性。结果表明:灰飞虱对噻虫嗪都处于敏感阶段(0.6~2.2倍);对烯啶虫胺处于敏感阶段(0.8~3.0倍);对毒死蜱产生了中-高水平抗性(17.5~83.6倍);对吡蚜酮为敏感到低水平抗性(1.9~5.5倍);对噻嗪酮的抗性为高-极高水平(136.4~271.1倍);对高效氯氰菊酯的抗性为低-中等水平(5.2~34.9倍);对氟虫腈为低水平抗性(0.9~8.0倍)。基于灰飞虱对7种药剂的抗性情况,对田间治理灰飞虱合理使用药剂进行了讨论。     

昆虫对拟除虫菊酯类杀虫剂的代谢抗性机制研究进展

随着拟除虫菊酯类杀虫剂在卫生和农业害虫防治中的广泛应用,昆虫对此类杀虫剂产生抗性的报道越来越多。目前已明确昆虫对拟除虫菊酯类杀虫剂的抗性机制包括表皮穿透率下降、靶标抗性以及代谢抗性,其中代谢抗性机制较为普遍,而且其与昆虫对多种杀虫剂的交互抗性关系密切。目前,随着基因组、转录组以及蛋白质组学等新技术的发展及应用,昆虫对拟除虫菊酯类杀虫剂的代谢抗性机制研究也取得了很多新进展。昆虫体内细胞色素P450酶（P450s）、羧酸酯酶（CarE）及谷胱甘肽S-转移酶（GSTs）等重要解毒酶系的改变均与昆虫对拟除虫菊酯类杀虫剂的代谢抗性有关,其中这3类解毒酶的活性及相关基因表达量的变化是昆虫对此类杀虫剂产生代谢抗性的主要原因。明确昆虫对拟除虫菊酯类杀虫剂的代谢抗性机制,对合理使用此类杀虫剂及延缓抗药性的产生均具有重要意义。本文在总结拟除虫菊酯类杀虫剂代谢路径及相关生物酶研究概况的基础上,综述了近年来有关昆虫对此类杀虫剂代谢抗性机制研究的主要进展。     

Modeling dose-response relationships in biological control: partitioning host responses to the pathogen and biocontrol agent

ABSTRACT Breeding plants to improve the effectiveness of biocontrol agents is a promising approach to enhance disease suppression by microorganisms. Differences in biocontrol efficacy among cultivars suggest there is genetic variation for this trait within crop germplasm. The ability to quantify host differences in support of biological control is influenced by variation in host response to the pathogen and the dose of pathogen and biocontrol agent applied to the host. To assess the contribution of each of these factors to successful biocontrol interactions, we measured disease over a range of pathogen (Pythium) and biocontrol agent (Bacillus cereus UW85) inoculum doses. We fit dose-response models to these data and used model parameter estimates to quantify host differences in response to the pathogen and biocontrol agent. We first inoculated eight plant species separately with three species of Pythium and evaluated three dose-response models for their ability to describe the disease response to pathogen inoculum level. All three models fit well to at least some of the host-pathogen combinations; the hyperbolic saturation model provided the best overall fit. To quantify the host contribution to biological control, we next evaluated these models with data from a tomato assay, using six inbred tomato lines, P. torulosum, and UW85. The lowest dose of pathogen applied revealed the greatest differences in seedling mortality among the inbred lines, ranging from 40 to 80%. The negative exponential (NE) pathogen model gave the best fit to these pathogen data, and these differences corresponded to model parameter values, which quantify pathogen efficiency, of 0.023 and 0.091. At a high pathogen dose, we detected the greatest differences in biocontrol efficacy among the inbred lines, ranging from no effect to a 68% reduction in mortality. The NE pathogen model with a NE biocontrol component, the NE/NE biocontrol model, gave the best fit to these biocontrol data, and these reductions corresponded to model parameter values, which quantify biocontrol efficiency, of 0.00 and 0.038, respectively. There was no correlation between the host response to the pathogen and biocontrol agent for these inbred lines. This work demonstrates the utility of epidemiological modeling approaches for the study of biological control and lays the groundwork to employ manipulation of host genetics to improve biocontrol efficacy.     

A genomics approach to crop pest and disease research

Genome-wide analyses of gene function and gene expression are beginning to yield valuable information in many areas of biological research, and these genomic tools are now being applied to crop pest and disease research. DNA sequencing of cDNA libraries to generate sets of expressed sequence tags (ESTs) are allowing gene compendiums for crop diseases to be compiled. Annotation of such data collections is also providing a wealth of functional information about gene products through similarities to proteins with known function. The next phase of the functional genomics era will be to employ large-scale techniques to knock out or silence genes in order to synthesize gene-specific mutants for phenotypic analysis and to use micro-array methodology to analyze global gene expression, protein turnover and protein processing during the processes of parasitism and colonization. Application of these technologies promises to accelerate the pace that biological information relevant to crop protection accrues. The ability of researchers to assimilate this information into complex models and workable hypotheses is, thus, set to revolutionize the way we study pests and diseases of crop plants.     

保护祁连山水资源,稳定河西生态平衡

甘肃河西地区地处欧亚大陆腹地,气候极端干燥,年平均降水量约40—200mm。水源缺乏,农、林、牧生态系统十分脆弱。雪线与冰川后退,总经流减少11.77%,泉水减少17.8%。祁连山森林遭受破坏,森林面积减少16.5%,因此,恢复与稳定河西生态系统是发展河西工农业生产,改善人民生活环境的首要战略任务。主要措施是:防止雪线和冰川后退,保护和扩大祁连山水源涵养林,大力营造绿洲农田防护林,保护和封育荒漠天然植被,改善现有水利设施,加强水利工程建设,减少水份的散失量、提高水资源的合理利用率。     

对国家春小麦西北旱地区域试验的几点认识

本文通过4a的实地调查和对区域试验结果的统计分析，针对国家春小麦西北旱地区域试验存在问题的分析，提出在均衡布点的基础上，要加强区试点基础设施建设、提高管理水平、保持试验地块的稳定性、提高旱地试验出苗率、注意病虫害的防治、增加辅助对照品种和提高人员素质等。     

介孔活性炭表面改性对两种农用抗生素吸附性能的影响

研究了介孔活性炭通过用硝酸和氨水进行表面改性后对2种农用抗生素——阿维菌素和井冈霉素吸附性能的影响。结果表明:硝酸可增加介孔活性炭表面的酸性亲水基团,从而增加了对亲水性药物井冈霉素的吸附量,但却降低了对疏水性药物阿维菌素的吸附量;但当硝酸质量分数超过55%、温度超过60 ℃时,硝酸的强氧化作用会破坏活性炭的部分孔隙结构,使其对井冈霉素的吸附量有所下降。与之相反,氨水则因减少了介孔活性炭表面的酸性亲水基团而对阿维菌素的吸附量有所上升。利用SAS统计软件进行相关性分析,证实介孔活性炭表面酸性基团数量、尤其是羧基的数量与其对井冈霉素和阿维菌素的吸附量呈极显著相关,相关系数分别为0.560 2和-0.873 7。由此推断:增加介孔活性炭表面的酸性亲水基团,可以在一定程度上增加活性炭对亲水性药物的吸附量;而增加疏水性基团,则可以增加其对疏水性药物的吸附量。     

Subjective components of mildew assessment on spring barley

The severity of mildew on barley is usually assessed visually and this leads to variation between different scorers. Field assessments by four assessors were analysed to determine the nature and degree of subjective discrepancies between assessors. Two inexperienced assessors failed to detect a major effect of nitrogen due to differences in the interpretation of a scoring system. A computer-based training programme was evaluated for standardising assessments, and was found to improve assessors' accuracy. Linear regression analysis was used here to resolve the error variance into components representing the accuracy and precision of the assessors. Plots of the cumulative differences between the estimate of disease severity by each assessor and the best estimate were used to display how the discrepancies varied with the level of disease. Some modifications to the barley field scoring system are suggested to improve comparability between assessors.     

Resistance in winter wheat lines to deoxynivalenol applied into florets at flowering stage and tolerance to phytotoxic effects on yield

In Europe and North America, deoxynivalenol (DON) is the most prevalent mycotoxin associated with wheat head blight caused by Fusarium graminearum and Fusarium culmorum. Because DON is toxic to plants and enhances the ability of the pathogen to spread within a spike, wheat lines with resistance to DON should be more resistant to head blight. Resistance to DON has been associated with resistance gene Fhb1 that confers resistance to spread within a spike. The objectives of this study were to determine if wheat lines resistant to head blight were also resistant to DON, if genes other than Fhb1 confer resistance to DON, and to identify lines able to fill grain in the presence of DON. Susceptible controls and diverse North American and European winter wheat lines with resistance to head blight were screened for molecular markers linked to known head blight resistance genes, and evaluated in a greenhouse for resistance to DON and relative yield after application of DON to spikes at flowering. Fhb1 appeared to have the unique ability to confer resistance to DON, as measured by the number of DON‐bleached primary florets. However, this resistance did not protect plants from the phytotoxic effects of DON on kernel formation as measured by the relative yield of treated spikes. Furthermore, measuring the relative yield loss following DON application may be useful for identifying lines with tolerance to head blight.     

小菜蛾对溴氰菊酯抗性选育及其机理

本研究用溴氰菊酯在室内以点滴法处理小菜蛾４龄幼虫，连续继代药剂淘汰选育其抗药性，至Ｆ６５代，抗药性提高到１１６３倍，已形成高抗生品系。其抗性的形成发展趋势为前期相对缓慢，中期较快，后期迅速增长。于１９９２、１９９３、１９９４年分别以氯氰菊酯、敌敌畏、杀虫双、灭虫剂有明显 正交互抗性，对其它非菊酯类杀虫虫没有产生交互抗性。用聚丙烯酰胺凝胶电泳地（ＰＡＧＥ）测定表明，小菜蛾对溴氰菊酯抗性的产生可能与非     

Differential susceptibility to abamectin and two bioactive avermectin analogs in abamectin-resistant and -susceptible strains of Colorado potato beetle, Leptinotarsa decemlineata (Say) (Coleoptera: Chrysomelidae)

As resistance to currently used insecticides increases in the Colorado potato beetle (CPB), Leptinotarsa decemlineata (Say), abamectin and its 4″-epi and 8,9-oxide analogs may serve as likely replacements if proven effective. We previously selected an abamectin-resistant strain of CPB (AB-F) that is suitable for the determination of cross-resistance to these two bioactive avermectin analogs. Using bioassay and logit analysis, the present work shows that, on average and following normalization by weight, the larval stages of the insecticide-susceptible SS strain are equally sensitive to the toxic action of abamectin and its 4″-epi and 8,9-oxide analogs, indicating that all three compounds retain high bioactivity towards the susceptible larval stages. Abamectin and the two analogs also are similar in toxicity to the larval stages of the AB-F strain. However, the AB-F larval stages are significantly less sensitive on average to these insecticides than the SS larval stages, indicating resistance to abamectin and cross-resistance to both the two analogs tested. Likewise, adults of the AB-F strain are significantly less sensitive to the toxic action of abamectin and the two analogs compared to SS adults, also indicative of resistance and cross-resistance. Abamectin is significantly more toxic, however, to both SS and AB-F adults, respectively, than either of the two analogs. The reduction in sensitivity was particularly evident in SS adults to both the 4″-epi and 8,9-oxide analogs. Additionally, adults of the SS strain are significantly less sensitive to the toxic action of abamectin and the two analogs when compared to SS larval stages. There is no significant differences, however, in the toxicity of these three insecticides, respectively, between larval and adults stages of the AB-F strain. This phenomenon results in lower resistance ratio (RR) values calculated for the two avermectin analogs compared to those calculated for abamectin regardless of the insect stage examined but is particularly evident and significant in the adult stage. This relative decrease in resistance levels is primarily associated with SS adults that are less sensitive to the toxic action of these insecticides. The decrease in abamectin toxicity is apparently due to significantly increased levels of P450 associated with SS adults versus forth instars and to similar levels in adults of the SS and AB-F strains. Because abamectin resistance in CPB is due in large part to enhanced oxidative metabolism of abamectin, it is likely that the SS adults are more tolerant to abamectin due to an enhanced level of oxidative detoxification. Finally, neither abamectin nor the two analogs are structurally protected at the specific molecular locations, C₃″, C₂₄, and C₂₆ carbons, which leads to enhanced oxidative metabolism, resistance and cross-resistance. Structurally-protected avermectin analogs at these vulnerable intramolecular sites are likely to be more effective insecticides in suppressing the development of oxidative detoxification-based resistance to abamectin, as would the use of oxidative synergists.     

我国部分地区鲜食辣椒及其加工品中辣椒轻斑驳病毒的调查

本研究利用RT-PCR技术对我国部分地区鲜食辣椒和辣椒加工品中的辣椒轻斑驳病毒Pepper mild mottle virus(PMMoV)进行了调查。其中,鲜食辣椒样品(249份)中PMMoV检出率为75.5%;147份辣椒加工品中有97份检测到PMMoV,且所采集的每一类别的辣椒制品中都有阳性样品。调查结果表明:PMMoV不仅广泛分布于我国辣椒种植区,而且在多种辣椒加工品中的检出率也较高。该研究进一步明确了PMMoV的来源及可能的传播途径,为该病毒的防控提供了理论依据。