QUANTITATIVE DYNAMICS OF LARCH CATERPILLAR (DENDRALIMUS SUPERANS [BULLER]) AND THE BIOLOGICAL CONTROL

METHoDSoFlNVESTIGATIONIna24yearso1dlarchp1antation,asampleplotwassetup,inwhichloosam-pletreeswereselected.ThenumberoflarchcaterpillarsoneachsampletreewerecountedperiodicaI1y,whilethesameinves-tigationswerea1sodoneinlarchplanta-tionswithsameecologica1conditionssur-roundingthesamplep1ot.Asacontrol,ac-cordingtothedeve1opmentalprogressandlivinghabitsoflarchcaterpiIIar,thewholegenerationwasdividedintosevendevel0pmentaIstages:egg,firstinstar,thirdinstar(beforeoverwintering),fourthinstar(aft…     

Causes of outbreak of the larch caterpillar (Dendrolimus superans Butler) in Daxingan Mountain and its control strategy

In 1991, in Daxingan Mountain, an outbreak of larch caterpillar (Dendrolimus superans Butler) happened on large areas of more than one million hectares, where stands of larch were seriously damaged because needles on the trees were almost eaten up by the pest, causing enormous economic losses. Analysis of data collected indicated that the main cause of the outbreak of larch caterpillar on large areas was that, after thirty years of exploitation, mature and overmature forests decreased rapidly, middle-aged and young forests incresed in large amount, significant changes occurred in individual ecological conditions of stands, especially those tended, with decreasing canopy density and better light condition in the forest, and all these were adventageous to the outbreak of the pest. In addition, in recent years, the climatic condition in Daxingan Mountain changed significantly. The yearly average temperature raised gradually and the soil surface temperature in April and October increased year by year, which were advantageous to the outbreak of larch caterpillars. In short, the significant changes in the ecological conditions in Daxingan Mountain provided suitable conditions for the outbreak of the larch caberpillar, and after several years of increase in population number, the larch caterpillar outbroke into a serious disaster on vast areas. In the paper, composite control strategy was also discussed.     

潮安县松毛虫发生规律及防治对策探讨

马毛松毛虫Dendrolimus punctatus Walker是我国森林的一种重要害虫，分布广、繁殖快、危害严重。在自然情况下，马尾松毛虫的大发生常表现出一定的周期性。但在人为干涉（防治）条件下，情况有时变得十分复杂。本文结合潮安县近30年的松毛虫发生、危害和防治情况以及与这相关的各种数据和资料，进行比较分析，试图从中了解和掌握本地区松毛虫的发生规律以及相应的防治对策，把松毛虫长期控制在有虫不成灾水平。     

落叶松枯梢病发生规律及防治技术

落叶松枯梢病Ｇｕｉｇｎａｒｄｉａｌａｒｉｃｉｎａ（Ｓａｗａｄａ）ＹａｍａｍｏｔｏｅｔＫ．Ｉｔｏ是我国北方落叶松人工林危害严重的病害。其发生与地形地势、风、树冠垂直高度、林分因子有关。加强检疫,适地适树造林,适时化防,把防治技术贯穿于造林、管理全过程的防治措施是有效的。     

肉桂双瓣卷蛾种群动态及综合治理研究

通过室内饲养和林间调查相结合的方法,研究了肉桂双瓣卷蛾的种群动态。该虫的发生、消长猖獗成灾与温度、湿度、林分结构和组成、林龄及天敌等环境因子有密切关系。提出了采取预防为主,营林技术措施为基础,生物防治为主导,科学地采取生物、人工、化学防治和保护利用天敌等的综合治理措施,可有效控制其危害。     

几种生物杀虫剂对杨扇舟蛾种群的控制作用

应用昆虫生命表技术,评价4种生物杀虫剂对杨扇舟蛾种群的控制作用。结果表明,0.3%印楝素乳油、1.8%阿维菌素乳油和Bt乳剂对杨扇舟蛾种群直接毒杀作用较好,但只施用1次不能将1代杨扇舟蛾种群趋势指数(I)降至1.000以下。0.3%印楝素乳油+Bt乳剂、0.3%印楝素乳油+1.8%阿维菌素乳油,对杨扇舟蛾的联合控制作用显著,I值均小于1.000,同时表明4种生物杀虫剂对天敌无毒副作用。     

广西大明山格木种群的空间分布格局与数量动态特征

在广西大明山保存较为完好的格木天然林内设置1块1 hm2固定样地,从种群空间格局、年龄结构、静态生命表和存活曲线4个方面研究种群的空间分布格局和数量动态特征。结果表明：大明山格木种群从幼龄和中幼龄到大树阶段,其空间分布格局由聚集分布逐渐变为随机分布,但总体上呈聚集分布格局;该格木种群年龄结构大致呈金字塔形,属于增长种群,考虑潜在干扰影响时种群仍处于稳定状态;种群内幼苗丰富,死亡率高,以3～4龄级种群数量变化最为剧烈,是种群动态变化的关键时期,后面龄级的个体比例较低,死亡率较早期明显下降;种群生存分析显示,死亡率、死亡密度和危险率均随龄级增加呈下降趋势,早期生存压力明显高于中后期,格木种群存活曲线为 Deevey存活曲线Ⅲ型。     

杨树烂皮病菌颉颃菌株的初步筛选与分子鉴定

对杨树烂皮病菌的平板对峙试验结果表明,6种颉颃真菌中木霉的抑菌率最高为51%,而颉颃细菌4个菌株的抑菌率均在60%左右,说明颉颃细菌的抑菌效果明显高于颉颃真菌;对B137等4株颉颃细菌的分子鉴定认为,1株为枯草芽孢杆菌(Bacillus subtilis),2株为解淀粉芽孢杆菌(Bacillus amyloliquefaciens),还有1株为苏云金杆菌(Bacillus thuringiensis,Bt);解淀粉芽孢杆菌和苏云金杆菌对杨树烂皮病菌有较好的颉颃效果。     

佳多频振式杀虫灯在松毛虫预测预报及防治中的应用

应用佳多频振式杀虫灯对松毛虫Dendrolimus spp.进行预测预报和防治试验,结果证明对松毛虫成虫有诱集作用,完全可以用于对松毛虫的监测.在利用佳多频振式杀虫灯进行马尾松毛虫Dendrolimus punctatus Walker防治试验中,取得了平均85%以上的防治效果,成本远低于其他防治措施的成本.     

Population dynamics and considerations for the conservation of the rare Cycas fairylakea in China

Quantitative dynamics and viability of a rare and wild Cycas fairylakea population were studied with a time-specific life table,a Leslie matrix model and a survival function in order to provide scientific guidance for its protection.The results of the timespecific life table show that this C.fairylakea population suffered a high death rate in three age classes,i.e.,age class I(0-15 years), V(61-75 years)and VI(76-90 years).The Leslie matrix model suggests that the number of plants would decline from the present 1613 to 59 per hectare in 150 years.Furthermore,the viability analysis indicates that seedlings have the highest mortality density rate and that middle-aged plants(i.e.,61-75 years,76-90 years)have high mortality density rate and hazard rate.These conditions affect natural regeneration of the population and lead to a lack of seedlings which in turn causes the extinction of the population.An in situ conservation of the population should be established and protection measures taken as soon as possible.     

中国特有植物四合木种群结构及动态研究

研究了四合木种群的径级结构、冠幅结构,高度结构和年龄结构,运用静态生命表描述了四合木种群年龄结构动态变化规律。研究表明：四合木种群株数随径级、高度级的变化呈“山峰型”,植株数随冠幅变化成倒“Ｊ”型,现实的四合木种群年龄结构呈“凸”型。四合木种群的死亡率ｑｘ,致死力ｋｘ随龄级增大而增高,存活率ｌｘ随龄级增大而降低。其存活曲线接近于ＤｅｅｖｅｙⅠ型。利用Ｌｅｓｌｉｅ矩阵定量模拟种群动态,发现在受外界干     

Influence of food supplementation on the fitness of two biological control agents: a predatory nabid bug and a bollworm pupal parasitoid

Many arthropod predators and parasitoids exhibit either stage-specific or lifetime omnivory, in that they include extra-floral nectar, floral nectar, honeydew or pollen in their immature and/or adult diet. Access to these plant-derived foods can enhance pest suppression by increasing both the individual fitness and local density of natural enemies. Commercial products such as Amino-Feed^®, Envirofeast^®, and Pred-Feed^® can be applied to crops to act as artificial-plant-derived foods. In laboratory and glasshouse experiments we examined the influence of carbohydrate and protein rich Amino-Feed UV^® or Amino-Feed, respectively, on the fitness of a predatory nabid bug Nabis kinbergii Reuter (Hemiptera: Nabidae) and bollworm pupal parasitoid Ichneumon promissorius (Erichson) (Hymenoptera: Ichneumonidae). Under the chosen conditions, the provision of either wet or dry residues of Amino-Feed UV had no discernable effect on immediate or longer-term survival and immature development times of N. kinbergii. In contrast, the provision of honey, Amino-Feed plus extrafloral nectar, and extrafloral nectar alone had a marked effect on the longevity of I. promissorius, indicating that they were limited by at least carbohydrates as an energy source, but probably not protein. Compared with a water only diet, the provision of Amino-Feed plus extrafloral nectar increased the longevity of males and females of I. promissorius by 3.0- and 2.4-fold, respectively. Not only did female parasitoids live longer when provided food, but the total number of eggs laid and timing of deposition was affected by diet under the chosen conditions. Notably, females in the water and honey treatments deposited greater numbers of eggs earlier in the trial, but this trend was unable to be sustained over their lifetime. Egg numbers in these treatments subsequently fell below the levels achieved by females in the Amino-Feed plus extrafloral nectar and cotton extrafloral nectar only treatments. Furthermore, there were times when the inclusion of the Amino-Feed was beneficial compared with cotton extrafloral nectar only. Artificial food supplements and plant-derived foods are worthy of further investigation because they have potential to improve the ecosystem service of biological pest control in targeted agroecosystems by providing natural enemies with an alternative source of nutrition, particularly during periods of prey/host scarcity.     

板栗红蜘蛛的危害及其防治

板栗红蜘蛛主要危害板栗叶片，常造成板栗严重减产。用20%三氯杀螨醇，或40%毒死蜱，或40%氧化尔果乳油防治，施药3d后防治效果均达90%以上，施药6d后，40%氧化乐果乳油的防治效果达100%。     

五指山地区海南苏铁种群结构特征与动态

海南苏铁是海南岛特有种和国家I级重点保护植物,对研究热带植物区系具有重要意义。受生境缺失及人为干扰等因素影响,海南苏铁在海南岛的种群数量呈缩减态势。采用种群年龄结构、静态生命表、存活曲线及种群动态量化分析等方法,对五指山地区不同生境下的海南苏铁种群进行了研究。结果表明:1)研究样地内的海南苏铁为稳定种群,低龄级和中龄级个体数占有一定的优势,但不同样地种群年龄结构存在一定的差异。2)静态生命表结果显示,3个样地整体上表现出随着龄级的增加高龄级个体数量减少的趋势,但样地A和样地B在幼龄级时有大量的个体数死亡。研究区内海南苏铁的存活曲线更趋近于Deevey-II型。3)种群动态量化分析结果表明,海南苏铁为低增长型的稳定种群,而样地A和样地B种群对外界干扰的敏感性要明显强于样地C。整体而言,五指山地区的海南苏铁种群当前仍处于一种稳定的状态。     

东莞莲花山毛棉杜鹃种群结构动态分析

采用相邻格子法设置1 200 m2样地调查广东省东莞市莲花山毛棉杜鹃(Rhododendron moulmainense) 所在群落。通过绘制种-面积曲线和拟合方程计算确定了毛棉杜鹃所在群落实际取样最小面积为900 m2。通过计算重要值来分析毛棉杜鹃所在群落的物种组成;将林木以胸径分级,以径级结构代替年龄结构,采用匀滑技术编制静态生命表,绘制存活曲线、死亡曲线和消失曲线,分析毛棉杜鹃种群结构和动态趋势。结果表明：调查群落优势种是毛棉杜鹃,林层结构简单,物种以地带性森林演替前期树种为主;毛棉杜鹃种群的径级分布呈倒“J”型,属增长型种群,种群在4龄级（大树）阶段发生波动;毛棉杜鹃主要通过萌蘖方式进行繁殖,萌蘖对幼树的贡献明显;毛棉杜鹃种群存活曲线趋向于Deevey-Ⅲ型。     

竹盲走螨、胡瓜钝绥螨对毛竹害螨的控制作用研究

应用实验种群生命表数据分析毛竹林本土优势种竹盲走螨和引进种胡瓜钝绥螨对毛竹4种害螨南京裂爪螨、竹裂爪螨、竹缺爪螨、竹刺瘿螨的控制能力。结果表明①胡瓜钝绥螨取食上述4种害螨的世代存活率分别为90．4％、77．55％、87．93％、81．63％，每雌总产卵量分别为38．12粒、45．77粒、35．59粒、30．26粒，而乡土优势种竹盲走螨取食上述4种害螨的世代存活率分别为95．23％、100％、87．7％、80．48％，每雌总产卵量分别为44．5、46．8、41．15、20．1粒；②竹盲走螨以南京裂爪螨为猎物时其内禀增长率(0．155)与引进种胡瓜钝绥螨(0．154)相近，均明显高于南京裂爪螨(0．1089)；③竹盲走螨以竹裂爪螨为猎物其内禀增长率(0．152)与胡瓜钝绥螨(0．152)相同但明显低于竹裂爪螨(0．192)；④竹盲走螨以竹缺爪螨为猎物时其内禀增长率为(0．148)明显低于引进种胡瓜钝绥螨(0．175)和其猎物(0．185)；⑤竹盲走螨取食竹刺瘿螨易大量逃跑，雌螨产卵量低，引进种胡瓜钝绥螨取食竹刺瘿螨能正常生长发育，但是其内禀增长率(0．144)明显低于其取食上述其余3种害螨的内禀增长率，产卵量高于当地种竹盲走螨，并描述1998年以来每年5—6月助迁人工繁殖的胡瓜钝绥螨控制毛竹害螨蔓延的效果。     

木兰围场天然次生油松林年龄结构及更新动态研究

通过对天然次生油松林下更新状况的调查,编制静态生命表、绘制存活曲线,研究分析河北木兰围场自然保护区内不同立地条件(坡底、坡中、坡顶)下天然油松次生林的年龄结构和更新动态,结果表明:(1)影响天然次生油松林更新的主要因子是郁闭度、灌草盖度。较高郁闭度、较高湿度更利于油松更新,幼苗更新密度最大值达4.192株/m2。(2)该保护区不同立地条件下油松种群年龄结构均为增长型年龄锥体;0~10a生个体数最多,坡中处最多达525株;生命期望最大值集中于10~20a龄级,该龄级属于生理旺盛期,应予以保护。(3)不同立地条件下油松种群的存活曲线变化趋势相似,油松存活率均在10~20a生间急剧下降;在20~60a生间,除坡底30~60a生存活曲线逐渐下降外,坡中和坡顶的存活曲线均大体趋于稳定,但60a生后3块标准地存活曲线均大幅下降,其中坡底处油松种群在70a存活率最小,为0;整体而言,存活率由大到小依次为坡顶、坡底、坡中。     

Effect of temperature on development and fecundity of Aphis gossypii Glover (Homoptera: Aphididae) on cucumber

The developmental time, survivorship and reproduction of Aphis gossypii Glover was evaluated on detached cucumber leaves at nine constant temperatures ranging from 15±1°C to 35±1°C in 2.5°C increments in the laboratory. Developmental periods of immature stages ranged from 10.8 days at 15°C to 4.1 days at 30°C and 32.5°C. Constant 35°C was lethal to immature stages of A. gossypii. The lower developmental threshold for the cotton aphid was estimated at 6.0°C and it required 92.6 degree–day development for a first instar to become adult. The average reproduction rate was 82.1 nymphs female^–1 at 25°C and 2.3 nymphs female^–1 at 32.5°C. The mean generation time of the population ranged from 6.8 days at 32.5°C to 22.8 days at 15°C. The highest per capita growth rate (r_m=0.526) occurred at 25°C and the lowest at 15°C (r_m=0.208) and 32.5°C (r_m=0.132). It was evident that temperatures over 30°C prolonged development, increased mortality of immature stages, shortened adult longevity and reduced fecundity. The optimal range of temperature for population growth of A. gossypii on cucumber was very broad and ranged between 22.5°C and 30°C.     

五加异个木虱越冬代成虫田间动态与防治技术

五加异个木虱是危害短梗五加的专食性害虫,为掌握该害虫越冬代成虫的田间动态和防治技术,使用不同手段处理地面并悬挂黄色粘虫板诱捕成虫。结果显示:与未悬挂粘虫板的地块相比,悬挂粘虫板的自然状态、清理地面、覆盖地膜3种处理地块五加异个木虱虫瘿数量分别降低82.23%、93.19%、98.50%;在悬挂粘虫板的3种处理中,以覆盖地膜处理的防治效果最好。建议于越冬代成虫活动前,在田间清理地面枯枝落叶并覆盖地膜,以实现五加异个木虱的无公害防治。