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21.
果树介壳虫寄生蜂资源的研究 总被引:4,自引:0,他引:4
介壳虫是果树的重要害虫,研究利用寄生蜂的自然控制作用是果树介壳虫生物防治和综合治理的重要途径。本论述了果树介壳虫寄生蜂资源的研究,报道了小蜂总科寄生蜂5科25属63种。 相似文献
22.
J. Francisco-Ortega H. J. Newbury B. V. Ford-Lloyd 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1993,87(1-2):264-270
Random Amplified Polymorphic DNA (RAPD) was used to generate molecular markers to trace the origin of the fodder legume tagasaste (Chamaecytisus proliferus (L. fil.) Link ssp. palmensis (H. Christ) Kunkel) in the Canary Islands. Results from multivariate analyses of data through Two Way Indicator Species Analysis (TWINSPAN) and Detrended Correspondence Analysis (DECORANA) showed that genotypes collected on the island of La Palma exhibited a wider range of variation than those from the other islands. This supports the existing hypothesis that tagasaste originated on La Palma and emphasizes the importance of conserving and evaluating germ plasm from this island. 相似文献
23.
Petra Sumasgutner Susan J. Cunningham Arne Hegemann Arjun Amar Hannah Watson Johan F. Nilsson Martin N. Andersson Caroline Isaksson 《Global Change Biology》2023,29(9):2399-2420
Climate change and urbanisation are among the most pervasive and rapidly growing threats to biodiversity worldwide. However, their impacts are usually considered in isolation, and interactions are rarely examined. Predicting species' responses to the combined effects of climate change and urbanisation, therefore, represents a pressing challenge in global change biology. Birds are important model taxa for exploring the impacts of both climate change and urbanisation, and their behaviour and physiology have been well studied in urban and non-urban systems. This understanding should allow interactive effects of rising temperatures and urbanisation to be inferred, yet considerations of these interactions are almost entirely lacking from empirical research. Here, we synthesise our current understanding of the potential mechanisms that could affect how species respond to the combined effects of rising temperatures and urbanisation, with a focus on avian taxa. We discuss potential interactive effects to motivate future in-depth research on this critically important, yet overlooked, aspect of global change biology. Increased temperatures are a pronounced consequence of both urbanisation (through the urban heat island effect) and climate change. The biological impact of this warming in urban and non-urban systems will likely differ in magnitude and direction when interacting with other factors that typically vary between these habitats, such as resource availability (e.g. water, food and microsites) and pollution levels. Furthermore, the nature of such interactions may differ for cities situated in different climate types, for example, tropical, arid, temperate, continental and polar. Within this article, we highlight the potential for interactive effects of climate and urban drivers on the mechanistic responses of birds, identify knowledge gaps and propose promising future research avenues. A deeper understanding of the behavioural and physiological mechanisms mediating species' responses to urbanisation and rising temperatures will provide novel insights into ecology and evolution under global change and may help better predict future population responses. 相似文献
24.
中国优质水果资源的分布与适宜生态环境 总被引:3,自引:0,他引:3
根据农业部在80年代两次组织评选出的全国189个优质水果产地的生态环境资料,用微型电子计算机系统建立数据库,统计分析柑桔、苹果和梨优质产品的构成比例、产区分布地域及其适宜的环境指标和主栽品种的生态适应性,为果树良种区域化栽培与选育提供依据。 相似文献
25.
Jeffries et al. (2018) investigated testing for a treatment difference in the setting of a randomized clinical trial with a single outcome measured longitudinally over a series of common follow-up times while adjusting for covariates. That paper examined the null hypothesis of no difference at any follow-up time versus the alternative of a difference for at least one follow-up time. We extend those results here by considering multivariate outcome measurements, where each individual outcome is examined at common follow-up times. We consider the case where there is interest in first testing for a treatment difference in a global function of the outcomes (e.g., weighted average or sum) with subsequent interest in examining the individual outcomes, should the global function show a treatment difference. Testing is conducted for each follow-up time and may be performed in the setting of a group sequential trial. Testing procedures are developed to determine follow-up times for which a global treatment difference exists and which individual combinations of outcome and follow-up time show evidence of a difference while controlling for multiplicity in outcomes, follow-up, and interim analyses. These approaches are examined in a study evaluating the effects of tissue plasminogen activator on longitudinally obtained stroke severity measurements. 相似文献
26.
历经几代真菌人的艰苦奋斗,《中国真菌志》目前已出版65卷,其中子囊菌类有35卷、担子菌类26卷、接合菌类1卷、卵菌1卷、黏菌2卷;上述卷册记录923属9 228种及种下分类群。编研涉及大型和小型的类群、腐生菌、食药用菌、菌根真菌、作物和林木病原菌、捕食性真菌、虫生菌、菌生真菌以及毒菌等。编研过程中发现并发表了大量新分类群,丰富了对菌物物种多样性的认知。归纳已有成果,已立项卷册应加快编研和出版进度;资源调查与分类学研究需进一步加强,按分类群(专科、专属)继续开展编研工作,注重拟参编类群的前期研究积累;以下分类群值得在后续工作中予以关注:水霉目等部分卵菌、壶菌类、座囊菌纲部分类群、盘菌纲和锤舌菌纲中尚未参编的主要类群、伞菌纲中具有小型子实体的类群等。由于分类系统在不断更新和完善,已出版卷册中使用的部分名称和分类地位的处理需依据被大多数学者所公认的分类系统给予适时的订正。期待建设一支继往开来的菌物分类学研究队伍,不断取得令世人瞩目的编研成果,为我国菌物资源利用和物种保护提供科学依据。 相似文献
27.
28.
本文对特种油料植物的种质资源研究进行综述,这些植物包括含长链脂肪酸的Crambe,Limnanthes,Lunaria,短链脂肪酸的Cuphea,Lauraceae,羟基脂肪酸的Lesquerella,环氧脂肪酸的Vernonia,Stokesia,以及液体蜡酯的simmondsia等科、属的植物。 相似文献
29.
本文报道曲霉属及其相关的有性型属、即散囊菌属和裸胞壳属的分类群共15个,其中新变种1个,我国新记录3个。它们是:日本曲霉小囊变种(新变种),赭曲霉,蜂蜜曲霉,孔曲霉,埋藏曲霉(新记录),佩特曲霉(新记录)、亮白曲霉,阿姆斯特丹散囊菌,谢瓦散囊菌,腊叶散囊菌,赤散囊菌,匍匐散囊菌原变种,构巢裸胞壳,无冠裸胞壳和刺孢裸胞壳(新记录) 相似文献
30.
Food and water resources used by the Madagascan hissing-cockroach mite,Gromphadorholaelaps schaeferi
We determined the food source and water balance properties of the hissing-cockroach mite, Gromphadorholaelaps schaeferi. The food source for mites was identified using Evans blue dye by direct injection into a fasting host cockroach, Gromphadorhina portentosa, or by incorporation into cockroach food. No coloration was observed in mites on dye-injected cockroaches, but coloration was present in mites when only the food for the cockroaches had been stained. Thus, the mites are scavengers of cockroach food, and are not parasitic as previously thought. Our results demonstrate that the mites can absorb water from the air anywhere between 0.84 and 0.93 a
v
(%RH/100), and wax-block experiments revealed that the mouth is the site of uptake. The mites are normally clumped together on the host, typically in between the cockroach's legs and around the spiracles. Water loss rates for mites in groups (0.16% h-1) were far lower than for isolated mites (0.30% h-1), suggesting a group effect with regard to water balance. Above the transition temperature of 30°C rate of water loss was rapid. The sites occupied by mites on the cockroach's body seem to be highly specific for feeding and absorption of water vapour. 相似文献