НОВЫЙ ВИД РОДА NOTOPYGOS(AMPHINOMID AE,POLYCHAETA)ИЗ ЮЖНО-КИТАЙСКОГО МОРЯ С ОСТРОВОВ СИШАЦЮНЬДАО(ПАРАСЕЛЬСКИЕ ОСТРОВА)

1956—58.     

不同生长期内马铃薯块茎中酶作用下的淀粉转变之研究

在这篇论文中,引用了在不同生长期内马铃薯块茎提取液水解作用与磷酸化作用以及合成酶与磷酸葡萄糖变位酶活性的研究材料。用马铃薯块茎製备提取液,在两个时期来研究该提取液:第一次是在七月,即马铃薯开花的时候,那时马铃薯具有小的块茎;第二次是在收穫之後,与测定磷酸化酶和磷酸葡萄糖变位酶的活性的同时,测定块茎中澱粉含量,而且在提取液中测定还原性物质的含量。试验是用三个马铃薯品种进行的,即“劳尔赫”、“普列斯库里斯基”和“十月儿童”。对块茎提取液磷酸解作用的研究表明:块茎提     

Statures in Han populations of China

<正>Dear Editor,Shortly after initiating the"Physical Anthropological Research on Han Chinese"research project,we applied uniform sampling methods as well as methods and instruments of measurement to obtain a complete set of measurements of physical anthropological indicators among Han populations across China.Among these measurements,body stature was a key indicator.Currently,there should be reliable     

Aphid populations showing differential levels of virulence on Capsicum accessions

The green peach aphid,Myzus persicae,is one of the most threatening pests in pepper cultivation and growers would benefit from resistant varietices.Previously,we identified two Capsicum acessions as susceptible and three as resistant to M.persicae using an aphid population originating from the Netherlands(NL).Later on we identified an aphid population originating from a diferent gcographical region(Switserland,SW)that was virulent on all tested Capsicum acessions.The objeetive of the current work is to describe in detail diferent aspects of the interaction between two aphid populations and two sclected Capsicum acessions(one that was susceptible[PB2013046]and one that was resistant[PB2013071]to population NL),including biochemical processes involved.Electrical penetration graph(EPG)recordings showed similar feeding activities for both aphid populations on PB2013046.On acession PB2013071 the aphid population sw was able to devote significantly more time to phloem ingestion than population NL.We also studied plant defense response and found that plants of acession PB2013046 could not induce an accumulation of reactive oxygen species and callose formation after infestation with either aphid population.However,plants of PB2013071 induced a stronger defense response after infestation by population NL than after infestation by population SW.Based on these results,population SW of M.persicae seems to have overcome the resistance of PB2013071 that prevented feeding of aphids from NL population.The potential mechanism by which SW population overcomes the resistance is discussed.     

Influence of visual targets and landmarks on honey bee foraging and waggle dancing

Animals use diverse sensory stimuli to navigate their environment and to recognize rewarding food sources.Honey bees use visual atributes of the targeted food source,such as its color,shape,size,direction and distance from the hive,and the landmarks around it to navigate during foraging.They transmit the location information of the food source to other bees if it is highly rewarding.To investigate the relative importance of these attributes,we trained bees to feeders in two different experiments.In the first experiment,we asked whether bees prefer to land on(a)a similar feeder at a different distance on the same heading or on(b)a visually distinct feeder located at the exact same location.We found that,within a short foraging range,bees relied heavily on the color and the shape of the food source and to a lesser extent on its distance from the hive.In the second experiment,we asked if moving the main landmark or the feeder(visual target)influenced recruitment dancing for the feeder.We found that foragers took longer to land and danced fewer circuits when the location of the food source,or a major landmark associated with it,changed.These results demonstrate that prominent visual atributes of food sources and landmarks are evidently more reliable than distance information and that foraging bees heavily utilize these visual cues at the later stages of their journey.     

伤寒杆菌营养缺陷型活菌苗

<正> 一般公认,使用弱毒沙门氏菌活菌苗来抵御沙门氏菌的全身感染,其保护作用要比注射死菌苗好。 有证据表明,对于人的伤寒以及各种家畜的沙门氏菌感染来说情况也是如此。通过引入1个或1个以上分子特性已知的突变,导致机理清楚的毒力丢失而形成的无毒株作为活菌苗,似要比一些机理不清楚或不完全清楚而减毒了的菌株好得多。获得此类菌株的方法之一是诱发对一些代谢物有依赖性的不可逆突变。本实验室已经构建了好几株这样的伤寒杆菌突变株,其中的一株541Ty及其Vi-阴性变异株543Ty已进行了志愿者试验。下面介绍涉及使用营养缺陷型菌苗的一些原则以及对所构建的鼠伤寒沙门氏和都柏林沙门氏芳香簇依赖株的结果,即其效果能     

Sieve element occlusion provides resistance against Aphis gossypii in TGR-1551 melons

Feeding behavior and plant response to feeding were studied for the aphid Aphis gossypii Glover on susceptible and resistant melons(cv.Iroquois and TGR-1551,respectively).Average phloem phase bout duration on TGR-1551 was<7% of the duration on Iroquois.Sixty-seven percent of aphids on TGR-1551 never produced a phloem phase that attained ingestion(EPG waveform E2)in contrast to only 7% of aphids on Iroquois.Average bout duration of waveform E2(scored as zero if phloem phase did not attain E2)on TGR-1551 was<3% of the duration on Iroquois.Conversely,average bout duration of EPG waveform El(sieve element salivation)was 2.8 times greater on TGR-1551 than on Iroquois.In a second experiment,liquid nitrogen was used to rapidly cryofix leaves and aphids within a few minutes after the aphids penetrated a sieve element.Phloem near the penetration site was then examined by confocal laser scanning microscopy.Ninety-six percent of penetrated sieve elements were occluded by protein in TGR-1551 in contrast to only 28% in Iroquois.Usually in TGR-1551,occlusion was also observed in nearby nonpenetrated sieve elements.Next,a calcium channel blocker,trivalent lanthanum,was used to prevent phloem occlusion in TGR-1551,and A.gossypii feeding behavior and the plants phloem response were compared between lanthanum-treated and control TGR-1551.Lanthanum treatment eliminated the sieve element protein occlusion response and the aphids readily ingested phloem sap from treated plants.This study provides strong evidence that phloem occlusion is a mechanism for resistance against A.gossypii in TGR-1551.     

High levels of arbuscular mycorrhizal fungus colonization on Medicago truncatula reduces plant suitability as a host for pea aphids (Acyrthosiphon pisum)

This study sheds light on a poorly understood area in insect-plant-microbe interactions,focusing on aphid probing and feeding behavior on plants with varying levels of arbuscular mycorrhizal(AM)fungus root colonization.It investigates a commonly occurring interaction of three species:pea aphid Acyrthosiphon pisum,barrel medic Medicago truncatula,and the AM fungus Rhizophagus irregularis,examining whether aphid-feeding behavior changes when insects feed on plants at different levels of AM fungus colonization(42% and 84% root length colonized).Aphid probing and feeding behavior was monitored throughout 8 h of recording using the electrical penetration graph(EPG)technique,also,foliar nutrient content and plant growth were measured.Summarizing,aphids took longer to reach their 1st sustained phloem ingestion on the 84% AM plants than on the 42% AM plants or on controls.Less aphids showed phloem ingestion on the 84% AM plants relative to the 42% AM plants.Shoots of the 84% AM plants had higher percent carbon(43.7%)relative to controls(40.5%),and the 84% AM plants had reduced percent nitrogen(5.3%)relative to the 42% AM plants(6%).In conclusion,EPG and foliar nutrient data support the hypothesis that modifications in plant anatomy(e.g.,thicker leaves),and poor food quality(reduced nitrogen)in the 84% AM plants contribute to reduced aphid success in locating phloem and ultimately to differences in phloem sap ingestion.This work suggests that M.truncatula plants benefit from AM symbiosis not only because of increased nutrient uptake but also because of reduced susceptibility to aphids.     

Diapause affects cuticular hydrocarbon composition and mating behavior of both sexes in Drosophila montana

Envipnmental cues,mainly photoperiod and temperature,are known to control female adult reproductive diapause in several insect species.Diapause enhances female survival during adverse conditions and postpones progeny production to the favorable season.Male diapause(a reversible inability to inseminate receptive females)has been studied much less than female diapause.However,if the males maximized their chances to fertilize females while minimizing their energy expenditure,they would be expected to be in diapause at the same time as females.We investigated Drosophila montana male mating bchavior under short-day conditions that induce diapause in females and found the males to be reproductively inactive.We also found that males reared under long-day conditions(reproducing individuals)court reproducing postdiapause fermales,but not diapausing ones.The diapausing fies of both sexes had more long-chain and less short-chain hydrocarbons on their cuticle than the reproducing ones,which presumably increase their survival under stressful conditions,but at the same time decrease their attractiveness.Our study shows that the mating behavior of females and males is well coordinated during and afier overwintering and it also gives support to the dual role of insect cuticular hydrocarbons in adaptation and mate choice.     

苯二氮加强γ-氨基丁酸的作用原理

美国国立精神卫生研究院临床前药理实验室主任、国际《神经药理学》杂志主编E.Gosta 教授于1980年10月应邀访问中国,在北京、西安、上海、杭州等地进行多次学术报告。我们请作者将报告内容压缩整理后予以介绍,这是其中的一篇。