夹竹桃天蛾的生物学特性

夹竹桃天蛾Daphnis nerii(Linnaeus)是夹竹桃上的重要害虫,具有间歇性爆发的特点。该虫在湖南省衡阳地区1年发生2～3代,以蛹在寄主附近的枯枝落叶层、表层松土及土壤缝穴中越冬。越冬代成虫于6月上旬出现,6月中下旬产卵。6月下旬第1代幼虫孵化;第1代成虫于7月中旬出现,7月下旬产卵。第2代幼虫8月上旬孵化,8月下旬至9月上旬幼虫危害最历害,9月中旬开始化蛹,化蛹持续到10月中旬。第2代蛹发生分化,一部分成为越冬蛹,另一部分则羽化为成虫。第2代成虫于10月上旬开始产下第3代卵。10月上旬第3代幼虫开始孵化,11月中旬第3代幼虫开始化蛹、越冬。     

浙江省余姚地区松褐天牛的生活世代

松褐天牛Monochamus alternatus Hope是松材线虫(Bursaphelenchus xylophilus)病的主要传播媒介,明确松褐天牛的发生世代及成虫羽化规律对于松材线虫病的防控有着重要意义。本研究利用"塑料薄膜包裹松树树干、定期解除包裹供天牛产卵"的方法,系统研究了余姚地区松褐天牛的产卵规律及成虫的羽化规律。研究结果表明,成虫产卵期为5月上旬至8月下旬,高峰期出现在6月下旬至8月中旬。松褐天牛在浙江余姚多数为1年1代,部分为2年1代,95%以上的成虫集中在产卵后的第2年羽化,少数在第3年羽化。成虫自5月上旬开始羽化,高峰期出现在5月中旬到6月中旬,7月中旬羽化基本结束。     

二种脊漠甲的室内生物学特性观察

在宁夏银川利用室内自然条件比较观察了莱氏脊漠甲Pterocoma reitteri Frivaldszky和洛氏脊漠甲Pterocoma loczyi Frivaldszky的生物学特性。莱氏脊漠甲2年发生1代,以成虫和幼虫越冬,越冬幼虫于翌年6月下旬至9月上旬化蛹,羽化成虫7月上旬开始出现;洛氏脊漠甲2年发生1代,以成虫和幼虫越冬,越冬幼虫于翌年3月中、下旬出土活动,并在5月下旬至7月下旬化蛹,羽化成虫6月上旬出现。2种脊漠甲的幼虫在室内饲养条件下均有自相残杀的习性。     

核桃小吉丁虫研究初报

核桃小吉丁虫足陕西省核桃主要害虫。一年发生一代,以老熟幼虫在受害枯枝中过冬,极少数在活枝上越冬。4月中旬至6月底为化蛹期,盛期为4月底至5月初。蛹期平均27.7天,最短16天,最长39天。成虫羽化后在蛹室中停留4—20天才咬破皮层钻出枝外。5月上旬至7月上旬为成虫出现期,盛期为5月下旬至6月上旬。幼虫化蛹结束时亦即成虫出现高峰。成虫出枝后取食核桃叶,约经半个月补充营养期开始产卵。产卵需要较高的温度和强光,卵多产在伸出树冠外围的长枝条上叶痕附近。成虫生活期平均35.3天,最长可达83天。6月上旬至7月下旬为卵出现期。卵期多为10天。6月中旬至8月上旬为幼虫孵化期,7月上旬为孵化盛期。幼虫多在二、三年生枝条皮层中串圈为害。受害严重时树叶变黄、脱落,枝条干枯。8月下旬幼虫老熟后开始钻入木质部,做一蛹室,在蛹室中过冬,至10月底大部幼虫进入了越冬阶段。     

筛阿鳃金龟的生物学特性及其防治

筛阿鳃金龟是龙眼、荔枝的主要害虫,在广西南宁每年发生1代,以成虫越冬。翌年3月下旬或4月上旬成虫出土取食为害,直至5月中下旬成虫开始交配产卵,8月下旬或9月上旬为幼虫化蛹盛期,9月中下旬为成虫羽化盛期,随之出土取食为害,11月下旬入蛰。其主要以成虫为害植株的新梢嫩叶,而且每年出现两次为害高峰期,分别在当年9～10月和翌年4～5月。用40％氧乐果或50％甲胺磷乳油800～1000倍稀释液喷雾,防治效果显著。     

宽额螯蜂的幼期形态及生物学特性研究

宽额螯蜂Dryinus latus Olmi在山东商河寄生恶性席瓢蜡蝉Sivaloka damnosus Chouet Lu若虫,具有捕食和寄生的双重控制作用。首次明确该蜂寄主,记述其幼期形态特征、生活史、生活习性。在山东商河1年发生2代,以4龄老熟幼虫在茧内越冬。翌年4月下旬至5月上旬为化蛹盛期,5月中旬越冬代成虫开始出现,捕捉寄主若虫补充营养。成虫主要产卵于恶性席瓢蜡蝉3～5龄若虫前后翅芽下紧贴体背的淡绿色组织上。第1代卵历期平均78.1h,幼虫孵化至脱囊平均历时209.5h,产卵至脱囊平均历时280.0h,蛹期平均386.4h。幼虫作茧于枝条、叶片或地面枯叶上,茧外缀有枝条表皮或叶片碎屑。7月下旬至8月上旬出现第1代成虫,第2代幼虫8月上旬开始脱囊结茧越冬。野外寄生率27.8%～45.7%,控制作用显著。     

内蒙古荒漠草原亚洲小车蝗的种群动态

2010—2011年于内蒙古乌兰察布市四子王旗格根塔拉草原对亚洲小车蝗Oedaleus asiaticus(B.-Bienko)种群动态进行了研究。结果表明,亚洲小车蝗种群空间格局为随机分布;亚洲小车蝗于6月中旬开始孵化出土,1～3龄蝗蝻高峰期在6月中下旬至7月初,终见期在7月下旬;4～5龄蝗蝻于6月下旬始见,高峰期在7月上中旬,终见期在7月末;成虫于7月上旬始见,高峰期在7月中旬至8月下旬,终见期在9月上旬。应用最优分割法将亚洲小车蝗种群动态划分为3个阶段:(1)6月中旬,为蝗蝻开始出土期,数量稀少,空间格局为聚集分布或随机分布;(2)6月下旬至7月上中旬,为蝗蝻发生盛期,密度低时为随机分布,密度高时为聚集分布;(3)7月中下旬至9月上旬,为成虫发生期,空间格局为随机分布。     

跗粗角萤叶甲的生物学特性

跗粗角萤叶甲Diorhabda tarsalis Weise是甘草上的重要食叶害虫,成虫、幼虫危害甘草叶片及幼嫩组织。该虫在河北省保定1年发生3代,以成虫在土缝、洞穴或者枯枝落叶下面的疏松层中越冬。翌年4月下旬越冬成虫开始活动,4月下旬至5月上旬交配产卵,卵产于寄主根部10～15mm的疏松土层。第1代、第2代和第3代幼虫分别于5月中旬、7月上旬和8月上旬孵化,各代幼虫均能对寄主造成严重为害,幼虫3龄。记述该虫的寄主、生活年史、发育历期、生活习性,并提出防治建议。     

杨树粒肩天牛的生物学特性

杨树粒肩天牛在福建省2a发生1代;老熟幼虫在第2年4月下旬至5月初开始化蛹,成虫出现期始于5月底6月初,6月中下旬到7月上旬为盛发期,9月上旬只见个别成虫;产卵期始于6月中旬,6月下旬至7月中旬为产卵高峰期;幼虫孵化期为6月下旬到8月中旬,7月上中旬为为盛发期;幼虫不越冬。杨树粒肩天牛成虫为补充营养所取食的树种较集中,主要是构树与桑树。杨树粒肩天牛幼虫对杨树危害严重,但成虫却不喜欢取食杨树,用杨树饲养的粒肩天牛成虫寿命很短,仅3-19d,不产卵;而以桑树为补充营养的雌成虫的平均寿命为55d、雄26.5d;以构树为补充营养的雌成虫的平均寿命为78d、雄45.5d,补充桑树与构树的粒肩天牛成虫均可正常产卵。雌雄成虫一生可多次交尾。雌虫有多次产卵现象,单雌每天产卵数量1-12粒不等。     

东北地区大豆田天敌昆虫优势种类分析

2005~2007年,对中国哈尔滨地区大豆田天敌昆虫开展系统调查。共发现5目、12科、33种天敌昆虫。龟纹瓢虫Propylaea japonica(Thunberg)、异色瓢虫Harmonia axyridis(Pallas)、隐翅甲Ischnosoma sp.成虫和花蝽Oriussp.为大豆田优势种天敌昆虫。其中,隐翅甲Ischnosomasp.成虫于6月上旬至下旬田间发生。花蝽Oriussp.成虫6月下旬至8月下旬发生,异色瓢虫成虫6月下旬至9月下旬发生。龟纹瓢虫幼虫、异色瓢虫幼虫和花蝽Oriussp.若虫多于6月下旬至8月下旬,即大豆生育中期发生;龟纹瓢虫成虫田间发生期较长,大豆生育期中6月中旬至9月下旬均有发生。     

Cytoplasmic dynein-dependent vesicular transport from early to late endosomes [published erratum appears in J Cell Biol 1994 Feb;124(3):397]

We have used an in vitro fusion assay to study the mechanisms of transport from early to late endosomes. Our data show that the late endosomes share with the early endosomes a high capacity to undergo homotypic fusion in vitro. However, direct fusion of early with late endosomes does not occur. We have purified vesicles which are intermediates during transport from early to late endosomes in vivo, and analyzed their protein composition in two-dimensional gels. In contrast to either early or late endosomes, these vesicles do not appear to contain unique proteins. Moreover, these vesicles undergo fusion with late endosomes in vitro, but not with each other or back with early endosomes. In vitro, fusion of these endosomal vesicles with late endosomes is stimulated by polymerized microtubules, consistent with the known role of microtubules during early to late endosome transport in vivo. In contrast, homotypic fusion of early or late endosomes is microtubule-independent. Finally, this stimulation by microtubules depends on microtubule-associated proteins and requires the presence of the minus-end directed motor cytoplasmic dynein, but not the plus-end directed motor kinesin, in agreement with the microtubule organization in vivo. Our data strongly suggest that early and late endosomes are separate, highly dynamic organelles, which are connected by a microtubule-dependent vesicular transport step.     

Evidence for the retention of genetic variation in Erodium seed dormancy by variable rainfall

Summary The periodic occurrence of summer/early autumn precipitation in the California annual grassland can result in the formation of early and late emerging cohorts of Erodium botrys and E. brachycarpum. The occurrence of early rainfall and the timing of such rainfall are highly variable from year to year. A series of field watering experiments in 1980–81 were used to simulate early emergence conditions that would result from significant rainfall (1 cm) occurring in mid-July, late August, and mid-September. Net reproduction was used to estimate fitness differentials between Erodium cohorts emerging in response to a watering treatment (early emerging cohorts) and Erodium cohorts emerging with the onset of winter rains in mid-October (late emerging cohorts). Survival was lower and gross reproduction was higher among early emerging cohorts than late emerging cohorts. For both species, net reproduction of the early cohort was lower than that of the late cohort under the July watering treatment and higher than that of the late cohort under the August watering treatment.Early cohorts, formed in response to rainfall in mid-September, 1982, were also compared demographically to later cohorts emerging in October. Compared to late cohorts, net reproduction, gross reproduction and survival were higher for the early cohorts.Common garden experiments indicate that differences in the duration of seed dormancy between the progenies of early and late emerging plants reflect a significant genetic component. Progency produced by early cohorts of E. brachycarpum from all three watering treatments possessed more extended seed dormancy than progeny of late cohorts. In E. botrys, progeny from early cohorts emerging in response to the July watering treatment were also more dormant than late progeny. In contrast, early cohorts of E. botrys emerging in response to the September watering treatment produced seed less dormant than seed produced by late cohorts. When combined with demographic data, indicating that fitness differentials between early and late cohorts varied with changes in the date of early emergence, genetic results suggest that year to year variation in early rainfall may act to retain genetic variation in the duration of seed dormancy.     

Juvenile Barn Swallows Hirundo rustica L. from late broods start autumn migration younger,fuel less effectively and show lower return rates than juveniles from early broods

Long‐distance migratory passerines may exhibit different post‐fledging rearing times between their early and late broods due to limited time and energy resources. This could affect the migratory fuelling behaviour, condition and fitness of juvenile birds. We analysed long‐term (13‐year) biometric data (body mass, fat score) on Barn Swallows ringed at the nest and later recaptured during their initial stages of autumn migration. The return rates of early‐ and late‐born juveniles after overwintering in Africa were further compared to estimate their fitness. We found that juveniles from late broods started migrating south on average 11 days younger compared with juveniles from early broods. Body masses of nestlings did not differ between early and late broods, but juveniles from late broods were in better condition after leaving the nest, possibly due to a longer period of parental care. Having started migration, juveniles from late broods were, however, less efficient in accumulating energy than juveniles from early broods. A younger departure age, together with less efficient fuelling of late brood juveniles, may partly explain the 39% lower return probability and hence lower fitness value of late‐brood juveniles. Our study is the first to show that juveniles from the early and late broods exhibit different fuelling behaviour and departure strategies (in terms of age and timing), which may be reflected in the fitness value of offspring.     

Evolution of late H2A, H2B, and H4 histone genes of the sea urchin, Strongylocentrotus purpuratus.

Sea urchins possess several distinct sets of histone genes, including "early" genes, maximally active in cleavage and blastula stages, and "late" genes, active from the late blastula stage onwards. We determined the nucleotide sequences of six sea urchin (Strongylocentrotus purpuratus) late histone genes located on four genomic segments. Comparative analysis of these sequences identified several conserved elements in 5' flanking regions, including the sequences ATGPyATANTATA shared by all late genes and GGCGGGAAATTGAAAA shared by two late H4s. Comparisons of protein-coding sequences of late H4 and H2B genes with their early counterparts showed that silent sites have diverged to the theoretical maximum, indicating that early and late histone gene classes diverged at least 200 million years ago. Since extant echinoderms evolved from a common ancestor at about that time, it is likely that early and late histone gene sets are characteristic of all echinoderm groups. Amino acid sequences derived from nucleotide sequences of late H2A and H2B gistone genes differ substantially from amino acid sequences of their late counterparts. Most such differences are in highly mutable positions. A few, however, occur in positions that do not mutate frequently and thus may reflect functional differences between the early and late forms of the H2A and H2B proteins.     

Analysis of postinspiratory activity of phrenic motoneurons with chemical and vagal reflexes

We examined the effects of chemical and reflex drives on the postinspiratory inspiratory activity (PIIA) of phrenic motoneurons using a single-fiber technique. Action potentials from "single" fibers were recorded from the C5 phrenic root together with contralateral mass phrenic activity (also from C5) in anesthetized, paralyzed, and artificially ventilated cats with intact vagus and carotid sinus nerves. Nerve fibers were classified as "early" or "late" based on their onset of discharge in relation to mass phrenic activity during hyperoxic ventilation. Only the early fibers displayed PIIA but not the late fibers, even when their activity began earlier in inspiration with increased chemical drives. Isocapnic hypoxia increased, whereas hyperoxic hypercapnia shortened the duration of PIIA. Pulmonary stretch and "irritant" receptors inhibited PIIA. Hypercapnia and stimulation of peripheral chemoreceptors by lobeline excited both early and late units to the same extent, but hypoxic ventilation had a less marked excitatory effect on late fiber activity. Irritant receptor activation increased the activity of early more than late fibers. Hyperoxic hyperventilation eliminated late phrenic fiber activity, whereas early fibers became tonically active. Bilateral vagotomy abolished this sustained discharge in eight of nine early units, suggesting the importance of vagal afferents in producing tonic firing during hyperventilation. These results suggest that early and late phrenic fibers have different responses to chemical stimuli and to vagally mediated reflexes; late units do not discharge in postinspiratory period, whereas early fibers do; the PIIA is not affected in the same way by various chemical and vagal inputs; and early units that exhibit PIIA display tonic activity with hyperoxic hypocapnia.     

西藏飞蝗的生物学特性

西藏飞蝗Locusta.migratoria tibetensis Chen在四川甘孜州1年发生1代,某些地方(乡城县)1年发生不完整的2代,即以卵越冬,翌年3月下旬开始孵化出土,4月中、下旬为孵化盛期,1~3龄始盛期为4月中旬~5月中旬,高峰期为5月下旬,7月上旬初始羽化,7月下旬~8月上旬为羽化盛期,8月上旬始见产卵,8月下旬~9月上旬为产卵盛期,第1代成虫较早产下的卵块在条件适宜的情况下可于当年9月上旬孵化出土,但孵化出的蝗蝻不能越冬。该虫卵、全蝻期及全世代的发育起点温度分别为14.2,16.1,14.6℃,有效积温为179.1日.度、360.0日.度、787.8日.度。在18,21,24,27和30℃等5种恒温条件下其平均世代历期214.4,133.3,79.2,66.3和50.7d。     

Transport through the yeast endocytic pathway occurs through morphologically distinct compartments and requires an active secretory pathway and Sec18p/N-ethylmaleimide-sensitive fusion protein.

Molecules travel through the yeast endocytic pathway from the cell surface to the lysosome-like vacuole by passing through two sequential intermediates. Immunofluorescent detection of an endocytosed pheromone receptor was used to morphologically identify these intermediates, the early and late endosomes. The early endosome is a peripheral organelle that is heterogeneous in appearance, whereas the late endosome is a large perivacuolar compartment that corresponds to the prevacuolar compartment previously shown to be an endocytic intermediate. We demonstrate that inhibiting transport through the early secretory pathway in sec mutants quickly impedes transport from the early endosome. Treatment of sensitive cells with brefeldin A also blocks transport from this compartment. We provide evidence that Sec18p/N-ethylmaleimide-sensitive fusion protein, a protein required for membrane fusion, is directly required in vivo for forward transport early in the endocytic pathway. Inhibiting protein synthesis does not affect transport from the early endosome but causes endocytosed proteins to accumulate in the late endosome. As newly synthesized proteins and the late steps of secretion are not required for early to late endosome transport, but endoplasmic reticulum through Golgi traffic is, we propose that efficient forward transport in the early endocytic pathway requires delivery of lipid from secretory organelles to endosomes.