武夷山稻田生境越冬节肢动物群落的物种组成

2005年12月至2006年3月,采用吸虫器结合人工剥查的方法,对福建省武夷山稻田生境内的越冬节肢动物群落进行系统调查。共采集到节肢动物117种(或类),隶属于3纲13目58科,其中捕食性昆虫15种,蜘蛛23种,寄生性天敌29种,害虫27种,中性昆虫23种。     

Using species distribution models to locate animal aggregations: a case study with Hippodamia undecimnotata (Schneider) overwintering aggregation sites

1. The protection of animals' aggregation sites is increasingly seen as a key conservation strategy. However, to efficiently protect aggregation sites, they need to be accurately located. Species distribution models (SDMs) are an important tool in biological conservation to predict spatial distribution of species and they are used here to predict the distribution of the aggregation sites of a ladybird (Coleoptera: Coccinellidae) species. 2. Hippodamia undecimnotata forms spectacular overwintering aggregations at the same locations every year across southern and eastern Europe. In this study, an SDM was developed and its performance tested for H. undecimnotata aggregations in southwest France. Moreover, the study looked at how environmental variables correlate with ladybirds' abundance in the aggregation sites. 3. The occurrence of aggregations was best described by one model including isolated prominent object, pesticide risk, altitude and vegetation coverage. Furthermore, ladybird abundance at the aggregation sites is positively correlated with altitude. The SDM occurrence model performance was found to be high (area under the curve = 0.92 and true skill statistic = 0.78). 4. It is suggested that H. undecimnotata may be an umbrella species, because some aggregation sites were also used by other ladybird species. Therefore, the protection of the aggregation sites of this species may benefit several other species. 5. This study provides nature conservation stakeholders with a tool to locate overwintering aggregations, a first step towards the protection of these sites.     

Thermal biology of Typhlodromips montdorensis: implications for its introduction as a glasshouse biological control agent in the UK

The recent unexpected local establishment of a non‐native predatory mite, Neoseiulus californicus (McGregor) (Acari: Phytoseiidae), in the UK prompted us to undertake this study, which investigated the thermal biology of an alien species Typhlodromips montdorensis (Schicha) (Acari: Phytoseiidae). Laboratory and field experiments on its cold tolerance were used to assess its establishment potential outside of glasshouse environments in the UK. Currently, T. montdorensis is being tested as a glasshouse biological control agent against thrips and spider mites, but is not yet licensed for release in the UK. Typhlodromips montdorensis has a developmental threshold of between 10.3 and 10.7 °C, and a thermal budget of between 108.7 and 105.3 degree‐days when estimated by weighted and simple linear regression, respectively. Under outdoor conditions, T. montdorensis could theoretically complete up to six generations a year. The supercooling points of female and larval T. montdorensis were ?22 to ?24 °C with 100% pre‐freeze mortality apparent in both acute and chronic low temperature exposures. Typhlodromips montdorensis were unable to enter diapause under a selected laboratory regime. No reproduction occurred in the field from November to March, with 100% mortality within 7–14 days of release during this period. It is concluded that T. montdorensis would be a ‘safe candidate’ for introduction as a glasshouse biological control agent in the UK.     

Mechanisms underlying the effects of fall dormancy on the cold acclimation and winter hard- iness of Medicago sativa

As a global planting forage legume, alfalfa (Medicago sativa) is a valuable material to study the evolutionary and ecological mechanisms on plant adaptation to freezing due to their contrasting winter hardiness induced by fall dormancy (FD). This paper reveals that FD is an important growth characteristic that is adaptative to short-day and reducing temperature in late autumn, followed by a higher overwintering rate. Alfalfa cultivars are grouped into 11 FD ratings (numbered from 1 to 11), and this phenomenon is related to the extensive spread and cultivation for thousands of years in the globe. Alfalfa cultivars are under different climate habitats for a long time, leading to FD adaptive evolution, which provides rich genetic resources for human. In general, adaptative process associated with cold acclimation and winter hardiness in alfalfa is affected by FD, thus differences in winter hardiness exist among alfalfa cultivars. So far, regulation of FD by light and temperature and effects of FD on physiological and ecological processes involved in cold acclimation have been reported largely. However, signal transduction and the regulatory network associated with gene expression, especially the molecular mechanisms by which antifreeze proteins function in cold adaptation, are still poorly understood. Several scientific problems that need to be addressed in the future studies are highlighted in this review.     

温湿度对黄刺蛾越冬代成虫羽化的影响

研究温度、相对湿度等主要环境因子对黄刺蛾Cnidocampa flavescens(Walker)越冬代成虫羽化的影响。结果表明,20~30℃是成虫羽化的最适宜温度范围,其羽化率分别可达82.7%~87.3%,15℃和35℃下羽化率显著较低。高相对湿度对成虫羽化有利,RH80%和90%下羽化率分别为84.0%、81.0%,羽化率比RH70%以下显著提高。不同温度对黄刺蛾羽化进度有一定影响,在15,20,25,30,35℃下,其羽化高峰期分别出现在第5周、第4周、第2周、第2周和第3周;分别用直线回归和Logisitic回归模拟天数与累计羽化进度的关系,2种模型均极显著。用直线回归模型计算,越冬成虫在25℃下的理论羽化截止日期最早,时间为6月3日。     

不同棉蚜种群对棉花和黄瓜的适合度分化

通过室内转接试验,研究来源于越冬寄主花椒、木槿、石榴和夏寄主棉花、黄瓜共5个棉蚜Aphids gossypii Glover种群对棉花和黄瓜的适合度。结果表明:花椒棉蚜、木槿棉蚜、棉花棉蚜转接到棉花上的成虫留居率和种群繁殖率均明显地高于黄瓜;黄瓜棉蚜转接到棉花上的成虫留居率和种群繁殖率均显著地低于黄瓜;石榴棉蚜转接到棉花上的种群繁殖率显著低于黄瓜,但成虫留居率在2种寄主之间没有明显差异。     

温湿度对中华通草蛉越冬成虫存活的影响

室内研究了不同温湿度对中华通草蛉 (Chrysoperla sinica)越冬成虫存活的影响。试验采用因子二次正交旋转组合设计的要求安排 ,研究了越冬成虫在不同的温度组合条件下储存不同时间后的存活率 ,并得到了在不同时间后 ,成虫存活率与温湿度间的二次回归模型。结果表明 ,在试验条件下 ,越冬成虫存活的最佳条件组合是温度为 5℃和相对湿度为 75 % ,此条件下储存90 d的越冬成虫存活率达 85 %以上 ;温度对成虫存活率的影响最大 ,湿度次之 ,温湿度的交互作用最不重要。利用温湿度与存活率之间的回归方程 ,分析并得出了适宜于越冬中华通草蛉成虫存活的条件为温度 5～ 9℃ ,相对湿度 70 %～ 85 % ,温度和湿度过高或过低均不利于成虫的存活     

Winter survival and oviposition before and after overwintering of a parasitoid wasp, Ooencyrtus nezarae Ishii (Hymenoptera: Encyrtidae)

Winter survival and oviposition before and after overwintering in Ooencyrtus nezarae, an egg parasitoid of phytophagous heteropterans, were examined in Osaka, Japan. Eggs of Riptortus clavatus parasitized by O. nezarae were kept under natural photoperiod and temperature. When honey was supplied, some female adults emerging from early September to late November overwintered. The percentage of overwintering individuals increased as the date of adult emergence advanced. Most female adults supplied with honey and hosts oviposited soon after emergence, then stopped laying eggs. Female adults emerging in mid‐October and early November laid eggs and then overwintered. The induction of diapause in the field seems to vary greatly depending on host availability. Without honey, the survival time of female adults was very short, whether host eggs were supplied or not. After overwintering, most females began to lay eggs in early May if host eggs were supplied, and they produced both male and female progeny. In the study area, a legume field in Osaka, parasitization by O. nezarae was observed from early July to November.     

空心莲子草叶甲对越冬保护的响应与控害效能

空心莲子草叶甲Agasicles hygrophila是入侵杂草空心莲子草Alternan thera philoxeroide的重要天敌,冬春季低温冰冻是影响其安全越冬的关键胁迫因子。为了探明采取保护措施是否能提高越冬后的种群基数问题,在低温冰冻天气来临前,用塑料膜覆盖网室构建空心莲子草与空心莲子草叶甲保护生境(PH),分低温期(2009年1月21日至4月9日)、升温期(4月15日至5月1日)与自然生境(NH)中叶甲成虫初现期(从6月1日至29日)3个阶段,调查比较PH与NH两类生境中空心莲子草叶甲种群数量、结构、空间生态位分布特征及控害效能。结果表明:在保护生境中,低温期空心莲子草叶甲不休眠,且能安全越冬,当晴天温度较高时,成虫主要在直立茎或嫩枝上活动取食、补充营养,而在阴雨低温天气则停留在匍匐草层或土壤表层、缝隙中,少活动。随着气温回升,成虫转移到直立茎生态位上活动取食,并于4月上旬开始产卵繁殖,种群数量迅速增加,对空心莲子草的地上部分有较好的控制效果。在自然生境中,直到6月初才见少量成虫活动,此时草生长茂密,较低的空心莲子草叶甲种群难以发挥生防因子的作用。比较两种生境中6月1日与6月15日的控草效果显示,空心莲子草株高增长率分别为:PH-13.91%,NH-2.94%,NH中空心莲子草株高极显著高于PH,且单株生物量的控制率为PH(47.56%)极显著高于NH(4.89%)。在6月15日与29日的调查表明,单株叶片控制效果PH极显著优于NH,PH中的空心莲子草茎上均无叶,叶片或被取食殆尽、或被害后干枯脱落。茎被害率、茎蛀孔数与蛀茎率均为PH极显著高于NH。结果说明覆膜保护能显著提高叶甲越冬种群基数,使其提前进入繁殖期,从而能更有效地控制生境中的空心莲子草。     

异色瓢虫越冬聚集行为对其能量代谢的影响

异色瓢虫以成虫滞育越冬,越冬期间聚集行为尤为显著。为探讨异色瓢虫越冬聚集行为的适应意义,本研究利用便携式红外线CO2分析仪测定了6 种聚集度（分别用1头、2头、5头、10 头、20头和50头表示）下异色瓢虫越冬成虫的呼吸量,并通过呼吸量计算得到各聚集度下的呼吸速率（Respiration rate, Rr）和能量代谢速率（Metabolism rate, Rm）。结果表明: 不同聚集度间异色瓢虫越冬成虫的呼吸速率和能量代谢速率均存在显著性差异,相关性分析表明Rr和Rm值与聚集度之间呈显著负相关。即随着聚集度的增加,越冬成虫的呼吸速率和能量代谢速率呈逐渐降低的趋势。此外,利用“Y”形嗅觉仪测定了异色瓢虫实验种群和越冬种群成虫对不同味源的选择趋性,表明异色瓢虫均对各自的群体表现出趋性,而其越冬聚集行为的发生需要一种特殊的气味物质。本研究表明聚集行为可以有效降低异色瓢虫的新陈代谢速率,减少能量消耗,有利于其种群成功越冬,这对其越冬来说具有非常重要的意义。