蚕豆象综述

中国是世界上最大的蚕豆生产国,而蚕豆象是为害蚕豆的主要害虫,通常感染率为3%~100%,造成巨大的经济损失。信息化学物质是生物释放的能引起其他生物行为或生理反应的化学物质,在昆虫取食、寻找配偶、定向寄主、产卵等活动中起着极其重要的作用。根据国内外相关研究,从分布、形态特征、生活史、发育策略及化学生态学等方面对蚕豆象作了全面的综述,重点介绍了信息化学物质在蚕豆象综合防治中的应用前景,为蚕豆象绿色防控提供了新的思路。

斑痣悬茧蜂寄生、发育和生殖特征与寄主幼虫日龄的关系

【目的】"圆屋顶形"假说认为,对单寄生性姬蜂和茧蜂适合度而言,中间龄期幼虫寄主的品质高于更早和更晚龄期幼虫。该假说得到许多研究支持,但这些研究常以寄主幼虫脱皮划分虫龄,很少观测生殖特征,从而难以确切和全面描述适合度随寄主生长发育变化而变化的关系。本研究旨在检验"圆屋顶形"假说。【方法】本研究以斜纹夜蛾Spodoptera litura不同日龄幼虫为寄主,观测斑痣悬茧蜂Meteorus pulchricornis寄生和发育特征,并测定成蜂生殖力。【结果】线性回归分析表明,雌蜂对中间日龄寄主幼虫的寄生率大于对两端日龄寄主幼虫的寄生率;蜂卵至成虫的存活、成虫体型大小及其生殖力(产卵量)等适合度相关特征均表现出中间日龄寄主幼虫处理大于两端日龄幼虫处理。【结论】研究结果支持"圆屋顶形"假说。

Effects of light intensity on activity in four sympatric anuran tadpoles

Though light conditions are known to affect the development and anti-predation strategies of several aquatic species, relatively little is known about how different species react to light, or how light can affect these species during different points in their life-cycle. In this study, we used four sympatric anuran tadpoles （Bufo gargarizans, B. melanostictus, Pelophylax nigromaculatus and Microhyla fissipes） as animal system to examine species-specific activities of the underdoing different light intensity treatments, so as to better understand how they respond to light. We exposed four different species of tadpoles to 1660 and 14 lux light intensity treatments and then measured several parameters including development stage, body length and tail length, and as well as their basic activities. The results of this observation and analysis showed that the activities of tadpoles were significantly greater in B. gargarizans and B. melanostictus than in P. nigromaculatus and M. fissipes; and were also significantly greater during times of high light intensity as compared to during low light intensity. Moreover, the observed relationship between species and light intensity was significant. The activities ofB. gargarizans and B. melanostictus tadpoles were greater in high light, while the activity of P. nigromaculatus tadpoles was greater in low light intensity, while M. fissipes tadpoles showed no differences in either low or high intensity light. Furthermore, the activities orB. gargarizans, B. melanostictus and M. fissipes tadpoles in terms of developmental stage, body size or tail length did not seem to differ with light intensity, but during early larval developmental period of P. nigromaculatus, the activity of tadpoles was negatively correlated with development stage, but irrelevant to either body size or tail length in different light intensities. These results lead us to conclude the observed activities of the four sympatric anuran tadpoles are closely correlated with their specific anti-predation strategies.

Analysis of Art Education Innovation Strategy in Colleges and Universities in We Media Era

the education in colleges and universities is influenced with the coming of we media era and the art education in colleges and universities is presenting diversifled development trend. Therefore, under the background of we media, it is of great significance to strengthen the innovation strength of art education in colleges and universities and create a group of innovative art talents. Problems existed in art education in colleges and universities have been analyzed briefly and solutions for the problems have been proposed, in this way, the innovation level of art education in colleges and universities can be improved and the innovation ability of students can be cultivated.

From deception to frankness： Benefits of ontogenetic shift in the anti-predator strategy of alder moth Acronicta alni larvae

Animals can avoid predation by masquerading as objects that are not food to their predators. Alder moth Acronicta alni larvae go through an impressive ontogenetic change from masquerade to highly conspicuous appearance： early larval stages resemble bird droppings but in the last instar the larval coloration changes into striking yellow-and-black stripes. We hypothe- sized that such a change may be driven by differential predation favoring dissimilar anti-predator strategies in different life stages We show with a series of laboratory assays that larvae are distasteful to birds regardless of their developmental stage, suggesting that ontogenetic color change is not driven by the differential chemical defense. Birds showed higher variance in hesitation to- ward conspicuous prey; some individuals hesitated long time before attacking whereas all birds attacked instantly masqueraded prey. We also found that the activity level of the larvae increased with age, which fits to the fact that larvae need to move from foliage to pupation sites. In the field by using artificial larvae resembling the two life-history stages we found predation risk to vary during the season： In early summer larger yellow-and-black larvae were attacked most, whereas later in the summer small ＇bird-dropping-larvae＇ suffered the highest predation. We conclude that the ontogenetic switch from masquerading to aposema- tism is adaptive most likely because actively moving prey cannot mimic immotile objects and thus, aposematism during the ac- tive and vulnerable period when larvae are searching for pupation sites becomes beneficial

Multi-stemming strategies of Quercus glauca in an evergreen broad-leaved forest: when and where

Aims Multi-stemming supports plants’resilience to disturbances and then contributes to soil stabilization and forest function,especially in mountain habitats.Many questions remain about(i)the ontogenetic phase at which multiple stems can occur,(ii)how habitat drivers affect multi-stemming and(iii)whether ontogenetic phase and habitat drivers interact.We asked these questions for Quercus glauca(ring-cupped oak),the dominant species and sprouter across large warm-temperate areas of Asia;its multi-stemmed trees reflect individual survival,population regeneration and forest ecosystem stability.Methods In a 5-ha permanent plot of subtropical evergreen broad-leaved forest in eastern China,we examined the temporal patterns and spatial distribution of multi-stemmed trees of Q.glauca within 99 quadrats of 20 m×20 m.Important Findings There were three temporal modes for multi-stemming among the Q.glauca trees and most of them appeared to produce multiple stems from an early stage.Environmental disturbances related to slope convexity appear to be the main drivers of multi-stemming of Q.glauca.Moreover,the closer to the ridge,the earlier the multi-stemming occurs.Thus,also for other woody species in other forests and climate zones,ontogeny and environmental drivers promoting disturbance(not only geomorphology,but also extreme weather events,soil drought,fire),as well as soil fertility,need to be considered in combination to better understand multi-stemming and its consequences for community structure.