不同烟草品种对烟实夜蛾和棉铃虫产卵引诱作用的研究

田间调查表明,烟实夜蛾和棉铃虫混合种群在黄花烟草上的落卵量显著高于红花烟草,其百株卵量是红花烟草上的6~20倍.室内分析了烟草叶片挥发物和叶片浸洗物对2种夜蛾产卵行为的影响,结果表明,黄花烟草叶片粗提物对烟实夜蛾产卵有明显的引诱作用,烟实夜蛾在涂有黄花烟草叶片挥发物或叶片浸洗物纱布上的落卵量是红花烟草上的2~10倍;而棉铃虫则更喜欢趋向于红花烟草,在涂有红花烟草叶片挥发物或叶片浸洗物纱布上的落卵量是黄花烟草上的2~6倍.     

Explaining farmers’ reluctance to adopt green manure cover crops planting for sustainable agriculture in Northwest China

Green manure cover crops (GMCCs) planting has a potential for mitigating greenhouse gas emissions (GHG) in agroecosystems and provides important ecosystem services, thereby achieving the Sustainable Development Goals (SDGs) stipulated by the United Nations. However, the advantages of cultivating GMCCs on arable land are not widely recognized. For example, in the whole of China, the GMCCs planting area is less than 3.5% of total arable land. The aim of this study is to explore reasons for the low adoption rate of GMCCs planting. Using best–worst scaling (BWS) approach, farmers ranked their preferred conservation practices including three types of GMCC cropping systems. Taking Gansu Province in Northwest China as a case study, a survey with 276 farmers was conducted. The findings indicated that three factors are related to the low adoption rate of GMCCs: 1) farmers preferred improving farmland irrigation facilities and substituting chemical fertilizers with organic rather than planting GMCCs; 2) lack of awareness and understanding of government policy on GMCCs and limited access to training courses; 3) financial support and subsidies from the government are insufficient. This study provides insights and strategic implications for policymakers on how to further promote GMCCs in the future.     

沼气反应器中自动加热恒温系统主要工作部件的参数选择

自动加热恒温系统是沼气反应装置的主要工作部件,该系统设计的好坏,将决定料液是否能够高效稳定地产生沼气。而系统设计的好坏取决于工作原理是否正确、结构是否合理、主要工作部件的参数选择是否正确。为此,本文详细论述了自动加热恒温系统的结构、工作原理,合理确定了主要工作部件的参数,为本系统的加工、制造提供了理论依据。     

植物挥发物对蛾类昆虫行为影响的研究进展

概述了植物挥发物在蛾类昆虫定向、求偶、交配、产卵及幼虫取食等行为过程中的作用.指出植物挥发物对蛾类昆虫行为影响研究中存在以单个化合物对昆虫行为的调控作用研究为主,混合组分间相互作用机理、多生态因子对植物挥发物作用效果的影响、天敌昆虫在害虫治理中的作用等研究较少,理论成果未能与防治实践相结合等问题.提出应加强同种或同类挥发物对不同性别或不同生理状态下昆虫的作用效果差异及植物挥发物与蛾类性信息素协同作用等方面的研究,以便有针对性地进行害虫防治.     

不同水稻品种对白背飞虱产卵的影响

在自由选择试验中,白背飞虱(Sogatella furcifeta)在水稻品种上的产卵量与接虫12或24h后的栖息量呈极显著正相关;中抗品种Mudgo上的产卵量显著高于其它品种。在非自由选择试验中,感虫品种TN1和品系“9101”上的产卵量显著高于抗性和中抗品种(包括Mudgo)。分别罩笼时,Mudgo上的产卵量和取食量分别显著或极显著低于TN1;同罩一笼,产卵量差异不显著,取食量仍极显著低于TN1。稻株内游离氨基酸分析表明:白背飞虱的产卵量与亮氨酸和丙氨酸的含量呈极显著正相关,与赖氨酸,蛋氨酸,苯丙氨酸和天冬酰氨的含量呈显著正相关。     

水稻品种对白背飞虱取食及产卵行为的影响

以感虫品种Taichung Native 1(TN1)和Rathu Heenati(RHT)为对照,以取食量、产卵痕数、产卵量和卵孵化率为测定指标,研究了白背飞虱(Sogatella furcifera)在6个水稻品种上的取食与产卵行为的差异性.结果表明,水稻品种对白背飞虱的抗性表现出3种类型,即拒取食性为主、拒产卵性为主和拒取食性兼有拒产卵作用;水稻品种对白背飞虱拒取食和拒产卵作用间有一定相关性;水稻感、抗品种间卵的孵化率(发育率)无明显差异;在水稻抗白背飞虱产卵性的研究中,延长饲养时间是十分必要的.     

斑须蝽对寄主的选择性研究

斑须蝽是近几年大田作物发生危害较重的害虫之一,为了更好的对斑须蝽进行综合防治,进行了斑须蝽的寄主选择性研究。在实验室条件下利用四壁嗅觉仪测定了疯须蝽对玉米、向日葵、烟草、马铃薯、大豆的嗅觉反应,发现斑须蝽对大豆的选择趋向最明显;野外调查发现,斑须蝽对5种作物均取食为害,但对不同寄主取食偏好性不同,5种寄主植物中,斑须蝽最喜食大豆,在其它4种寄主上的取食选择性差异不大,室内试验和田间调查结论一致,斑须蝽对大豆的选择趋向性更强。     

Tracing possible drivers of synchronously fluctuating species catches in individual logbook data

Abstract Recreational fisheries statistics can provide valuable information on the dynamics of fish stocks and their exploitation. For some reservoirs in the Czech Republic, there are conspicuous synchronous fluctuations in catches of different species that might be caused by fishing skills and strategies. This study describes a method that could detect signatures of such phenomena in individual logbooks. It classifies anglers by species reported during 1 year and compares the resulting angler groups by group size, fishing effort, catch per unit effort (CPUE) and annual catch. The method is illustrated by data from one reservoir, showing that the number of generalist anglers who caught several species was higher than expected. Generalists also had higher catches and effort but lower CPUE than specialists who caught only one of the species. The results indicate that generalist anglers with a low degree of specialisation and high effort could contribute to long‐term correlations in species catches.     

杨树受光肩星天牛危害程度与树皮厚度的关系

为了解天牛对杨树的危害，分析了几种杨树上光肩星天牛排粪孔数与树皮厚度，树高的关系。发现在一定范围内，光肩星天牛在大径阶杨树上产卵与树皮厚度之间存在密切的负相关性。小径阶杨树上天牛产卵多在中下部，同样是由于树皮厚度所致。树皮厚度较树高与天牛产卵量关系更为密切，存在天牛产卵的最适树皮厚度。     

Movement and behaviour of large southern bluefin tuna (Thunnus maccoyii) in the Australian region determined using pop‐up satellite archival tags

Pop‐up satellite archival tags (PSATs) were deployed on 52 large (156–200 cm length to caudal fork) southern bluefin tuna (Thunnus maccoyii) in the western Tasman Sea during the austral winters of 2001–2005. Southern bluefin tuna (SBT) were resident in the Tasman Sea for up to 6 months with movements away from the tagging area occurring at highly variable rates. The data indicated a general tendency for SBT to move south from the tagging area in the Western Tasman Sea. Four individuals migrated west along the southern continental margin of Australia and into the Indian Ocean. Three individuals moved east into the central Tasman Sea, with one individual reaching New Zealand. We also describe the first observed migration of an SBT from the Tasman Sea to the Indian Ocean spawning grounds south of Indonesia. Individuals spent most of their time relatively close to the Australian coast, with an estimated 84% of time spent in the Australian Fishing Zone. SBT favored temperatures between 19 and 21°C, adjusting their depth to the vertical temperature distribution. Distinct diurnal diving patterns were observed and adjustment of depth to maintain constant ambient light levels over a 24‐h period. The findings of this study are a significant advance toward greater understanding of the spatial dynamics of large SBT and understanding the connectivity between distant regions of their distribution.