竹裂爪螨毛竹种群与慈竹种群对不同寄主植物的适应性及其生殖隔离

对危害毛竹(Phyllostachys pubescens)和慈竹(Neosinocalamus affinis)的竹裂爪螨(Schizotetranychus bambusae)两个种群进行相互间的食性选择和生殖隔离试验．结果表明,由于两种竹子叶片在物理结构上差异较大。尤其是慈竹叶片背面具有成排细茸毛,导致竹裂爪螨毛竹种群不能在慈竹叶上完成世代发育;竹裂爪螨慈竹种群能取食,危害毛竹叶片,但由于寄主转换后,对其生长发育不利,导致存活率低,繁殖力弱．两种群取食各自嗜食的寄主植物时,基本生物学特性存在差异,27℃条件下,当毛竹种群以毛竹为食时,种群的内禀增长率(rm)、周限增长率(λ)、净增殖率(Ro)分别为0．1415、1．1520和15．6298;慈竹种群以慈竹为食时,rm、λ、Ro分别为0．0993、1．1044、10．0622;慈竹种群取食毛竹叶片时,rm、λ、Ro分别为0．0391、1．0399和2．5542．生殖隔离试验表明,两种群间能互相正常交配,且互相交配的时间与两种群自交时的交配时间(1次)差异不明显．同一种群交配产生的后代,其性比均在2：1左右,而不同种群杂交产生的后代全部为雄性(竹裂爪螨为孤雌产雄),这表明两种群在长期的寄主植物选择压力下已形成一定的生殖隔现象．     

食物对竹裂爪螨生长发育及繁殖的影响

根据笔竹生长特性,用1年生竹、2年生竹、3年生竹和4年生竹的离体叶片作为食料,研究食用对竹爪螨（Schizoterranchus bambusae Peck)生长发育及繁殖的影响。试验结果表明,该螨各螨态的发育历期在4种食料组间存在显著差异或极显著差异,其中幼螨至成螨历期（雌螨）分别为5．00、5．10、6．31和5．03d;取食3年生竹叶片时,幼螨－成螨的存活率、单雌平均产卵量显著小于其余3组,分别为70．81％和14．71粒／雌。试验进一步研究了不同受害程度的毛竹叶片对竹裂爪生长发育及繁裂的影响,结果表明该螨各螨态的发育历期、雌成螨的寿命及敏殖力都因叶片的受害和蔼不同而存在显著差异或极显著差异,这表明了该螨种群在发展过程中,因对叶片的取食危害,通过对自身营养条件的恶化而存在着较强的负反馈作用。     

天敌竹盲走螨在纯竹林中种群数量锐减的原因研究

本项研究针对我国南方毛竹林,近年害螨突发性成灾的现象,进行调查与研究,结果表明：纯竹林害螨总量平均高于混交林289．28％,混交林天敌竹盲走螨(Typhlodromus bambusae Ehara)总量平均高于纯竹林263．56％;混交林益、害螨比例为1：13,而纯竹林益、害螨比例是1：118。研究表明纯竹林地面垦复、劈草,使得以芒草为生的芒草裂爪螨(Schizotetranychus mistanthi Saito)种群数量急剧下降,导致乡土优势种竹盲走螨缺乏中间食物,难以维持种群。在毛竹——芒草混生的毛竹林(含其它树种)由于毛竹上害螨和林下芒草裂爪螨受到共同天敌——竹盲走螨的控制维持着稳定的益、害种群数量,虽然有害螨,但不成灾,在纯竹林由于地面垦复、劈草破坏原有已形成的生物链,导致毛竹害螨失去天敌控制而突发性成灾,证明纯竹林中天敌锐减是导致毛竹害螨暴发成灾的重要因素。     

竹缺爪螨生态学初步研究

本报道严重危害毛竹生长和害螨－－竹缺爪螨在不同温度下生长,发育历期以及在竹林间种群动态。结果表明：在20－35℃范围内随着温度升高其发育历期缩短,温度与发育历期呈直线回归关系：Y全代＝651573-1.6250X（=-0.98);光照是影响竹缺爪螨的卵,幼螨存活及成螨产卵量的重要因素。在竹林间,毛竹换叶,降雨量,天敌数量是影响竹缺爪螨种群消长的和重要因素,最后提出综合防治的措施。     

温度对竹盲走螨实验种群数量消长的影响

在16、20、24、28和32℃5种恒温条件下以竹裂爪螨为食料对竹讯走螨（Typhlodromus bambusae E-hara)进行饲养,观察其生长发育各螨期的存活及成螨繁殖情况,进而组建竹盲走螨在5种恒温条件下实验种群的特定年龄生命表,并用Morris模型和Weibull频数分布函数探讨了温度对竹盲走螨实验种群数量变动的影响。结果表明,每雌平均产卵量在24℃时最大,为32.26粒,低于或高于24℃平均每雌产卵量均呈下降趋势。种群趋势指数（I)温度（T）之间呈二次函数关系（I＝－98.7747 9.6914T-0.2033T^2),理论上当温度为23.83℃时,种群趋势指数最大,繁殖一代后种群数量为上一代数量的16.74倍。通过Morris模型分析,表明每雌产卵量是影响该实验种群趋势指数的最重要因子。在试验温度范围内,竹盲走螨实验种群存活曲线均属Deevey Ⅰ型。     

苹果园二斑叶螨种群的空间格局

种群空间格局的研究是昆虫生态学的重要内容,它不仅揭示出种群的空间结构特征,而且还是确定抽样技术和资料代换的基础,二斑叶螨是苹果园的重要害螨,应用4种聚集度指标和Iwao法分别考查了该螨在苹果树内的空间格局及动态规律,结果表明,二斑叶螨在树内不同方向和高度上均以个体群的形式存在,个体群的分布为聚集分布,其中上层和南面树冠的聚集度最高,而下层和内部树冠的聚集度最低,造成这种差异与该螨的生物学特性和环境条件的异质性有关,不论螨体在上层,中层或下层树冠,都明显地表现出前期高聚块,6月中旬以后聚集强度逐渐降低的趋势。     

苹果全爪螨的空间分布格局及时序动态

苹果全爪螨是影响我国苹果生产的重要害虫之一.为明确其在苹果树冠上的时空格局,在2007年5-11月整个生长季节,采用不同方位、不同层面随机取样的方法调查害螨数量.应用聚集度指标法和Iwao回归测度法分析苹果全爪螨在苹果树上的分布型及其变化动态.结果表明:苹果全爪螨在苹果树冠整体范围内前期和中期符合负二项分布,呈聚集型,基本成分为个体群,且个体间相互吸引.聚集强度随种群密度的消长而波动,表现出高密度、低聚块及低密度、高聚块的规律,并且在树冠的不同方位和不同层面上存在一定差异:个体群的聚块性南部最高,西部最低;树冠中、下层高于上层,内层高于外层.     

柑橘全爪螨种群空间格局的地学统计学分析

应用地学统计学方法分析了柑橘园主要害螨柑橘全爪螨Panonychus citri（McGregor）种群的空间格局及其动态。结果表明,柑橘全爪螨种群具有空间相关性,变程介于1．10～21．0m,其半变异函数主要符合高斯模型,表现为聚集分布,其中3月、8月和9月的聚集强度较大;种群空间格局动态显示,4月、10月为该种群的两个发生高峰期,柑橘全爪螨种群数量快速上升扩散。地学统计学方法能够应用于柑橘全爪螨种群的空间格局分析,并有助于对该害螨进行发生预测与控制处理。     

土耳其斯坦叶螨自然种群生命表的研究

用分代隔离的方法,研究土耳其斯埋叶螨（Tetranychus turkestani Ugrov et Nikolsdi)6个世代的种种特定定年龄生命表。通过对其种群生命表的IPC指数分析得出：捕食性天敌和气候因子是影响土耳其斯坦叶螨种群数量消长的主要因素。天敌捕食和气候因子作用可分别使土耳其斯坦群种趋势指数降低17．9862和2．2793倍。     

Effects of the Nest Web and Female Attendance on Survival of Young in the Subsocial Spider Mite Schizotetranychus Longus (Acari: Tetranychidae)

The subsocial spider mite Schizotetranychus longus lives gregariously in woven nests on leaves of Sasa bamboo. Adults of both sexes defend their young against the predatory mite Typhlodromus bambusae. The effects of web and female attendance of this species on offspring survival were evaluated in a natural forest. Experimental removal of web and females revealed that S. longus young suffered greater mortality than in the control. Furthermore, the web made by parent females had a positive effect on offspring survival, possibly through preventing predators from intruding into the nest. Attendance of a female in a nest also had an effect on improving the survival rate of her offspring over a short period. We could not detect any function of the web and female other than protection against predators at least for the 5 day period of the experiment. The nest web of S. longus has an important function in the survival of young by preventing the entry of pedestrian predators (generalist) and females may play a role in defending against specialized predators which can intrude into the nests.     

Population Dynamics of Tetranychus Kanzawai (Acari: Tetranychidae) on Hydrangea

The seasonal occurrence of Tetranychus kanzawai Kishida populations on hydrangea (Hydrangea macrophylla) was studied at two different localities in Ibaraki, Japan, during a three-year period. There were two types of seasonal population trends: one with a population peak from May to June, and the other with the spring peak in June and the autumn peak in September–October. Each year the populations on hydrangea plants abruptly declined just after the spring peak. Predators showed a delayed density-dependent numerical response. The population crashed even in the absence of predators, suggesting that the predators had nothing to do with the June decline. Furthermore, the rate of development from larva to adult and the fecundity in adult females on detached hydrangea leaves decreased markedly just prior to the abrupt decline in density in June. Consequently, seasonal changes in plant quality (perhaps influenced by secondary compounds) seem to contribute to the drastic decline of T. kanzawai density on hydrangea in June.     

贵州雷公山秃杉的种群结构和空间分布格局

在贵州雷公山秃杉分布区域选择6类典型样地,运用相邻格子法,对秃杉种群进行生态学调查,采用空间序列代替时间序列的方法,编制种群的特定时间生命表与存活曲线,并应用均值(-X)、聚集度指数(I)、聚集指数(Ca)、扩散系数(C)、负二项分布指数(K)等聚集强度指数分析种群分布格局,为贵州雷公山秃杉种群的保护提供一定的理论依据。研究结果表明:(1)秃杉种群年龄结构呈金字塔形,幼苗严重不足,成年阶段个体较为丰富,种群有衰退趋势;(2)秃杉种群的死亡率qx从Ⅰ龄级至Ⅶ龄级增大,其中在Ⅴ龄级与Ⅵ龄级有两次死亡高峰,存活曲线基本接近DeeveyⅡ型;(3)种群分布格局整体上呈聚集分布。     

Spatial distribution and coincidence of Neoseiulus californicus and Tetranychus urticae (Acari: Phytoseiidae, Tetranychidae) on strawberry

In strawberry greenhouses in La Plata (Buenos Aires, Argentina), Tetranychus urticae is a major pest and Neoseiulus californicus is its most important established phytoseiid predator. The purpose of this study was to determine the spatial distribution and coincidence of N. californicus and T. urticae on strawberry. T. urticae populations exhibited density variations that were followed, with some temporal delay, by those of the predator. In general terms, N. californicus exhibited lower aggregation than T. urticae. The index of dispersion (I) of T. urticae had values significantly greater than 1 in 100% of the sampling dates. The percentage of infested leaflets increased with prey density in a curvilinear way, ranging from 80 to 100% when density was higher than 100 individuals/leaflet. N. californicus had values of I higher than unity in 86.7% (G1) and 53.8% (G2) of the cases. TaylorÕs b and IwaoÕs values were greater than 1 for both populations, this indicating aggregation. IwaoÕs results showed larger aggregation units of T. urticae (=53.24) than of N. californicus (=3.61), probably due to its higher fecundity and oviposition behaviour of laying eggs in clumps. Both populations were overdispersed, although in general terms, N. californicus exhibited lower aggregation than T. urticae. This would create refuges for the prey, thus increasing the persistence of the system. Index of coincidence of predator (Ic) was high most of the time even at low densities of both populations, decreased abruptly at the end of an interaction cycle and was similar at greenhouse and plant spatial scales. The high spatial coincidence of N. californicus with T. urticae suggests an important dispersal capacity of the predator and a high ability to detect leaflets with prey. The refuge index for the prey decreased with predator density and was higher at greenhouse scale than at plant scale, both at similar predator densities. At greenhouse scale and despite high predator density, the prey had a 10%-refuge, which would lead to the system persistence. Results of the present study suggest that N. californicus is a promising established natural enemy for controlling T. urticae on strawberry.     

Population dynamics of the citrus red mite, Panonychus citri (McGregor) (Acari: Tetranychidae) in Japanese pear orchards

In spring a population of the citrus red mite (Panonychus citri),a non-diapausing species, migrated to a Japanese pear orchard, mainly from nearby Japanese holly trees, but in autumn most of the mites starved to death while the rest returned to the holly trees. In the Japanese holly trees, the population of mites reached their maximum density in late May1993 and in mid-June 1994 on overwintered leaves and moved to newly opened leaves in mid-June 1993 and late June 1994. The mites tended to disperse abruptly in early June or mid-June and again towards the end of June. The mites inhabiting the holly trees appeared to migrate to the Japanese pear trees in June but their densities on pear leaves remained low until mid-August. In the pear orchard, the mites initially tended to increase on pear leaves near the holly trees and then gradually spread to other leaves farther away from the holly trees. Their highest density in the pear orchard occurred in mid-October. When pear leaves were inoculated with two or five female adults at different times from May to September, the leaves inoculated before mid-August showed no increase in the number of mites. A possible cause for the suppression of the population increase on pear leaves from June to mid-August is discussed. This revised version was published online in November 2006 with corrections to the Cover Date.     

油松种群自然更新格局的研究

种群的空间格局系指某一种群个体在其生存空间内相对静止的散布形式。它是种群的重要属性之一,是种的生物学特性对其所生存的环境条件在特定时期适应和选择的结果。空间格局的阐明,无论在理论生态学的研究上抑或     

比哈小爪螨实验种群生命表的研究

本文研究了比哈小爪螨5个温度梯度的实验种群生命表.结果表明15 ℃时内禀增长率和周限增长率均最小,分别为0.0235和1.0238,种群倍增时间最长(29.47 d);35 ℃时内禀增长率和周限增长率均最大,分别为0.3069和0.3592,种群倍增时间最短(2.26 d),说明高温有利于该螨种群的增长.25 ℃时净增殖率最大(56.30).35 ℃的世代生长周期最短(11.97 d).15 ℃时其寿命最长(98.90±20.77 d),35 ℃时寿命最短(19.00±3.11 d).最高平均产卵量71.60粒/雌和最高日平均产卵量4.10粒/雌/天均在25 ℃时出现.15 ℃时平均产卵量最低(8.80粒/雌),日平均产卵量仅有0.34粒/雌/天.最大日产卵量出现在35 ℃时(12.00粒/雌/天).     

Population dynamics of phytophagous and predatory mites (Acari: Tetranychidae, Eriophyidae, Phytoseiidae) on bamboo plants in Fujian, China

The seasonal cycle and population dynamics of Schizotetranychus nanjingensis Ma and Yuan, Aponychus corpuzae Rimando (Tetranychidae), Aculus bambusae Kuang (Eriophyidae) and their natural enemy Typhlodromus bambusae Ehara (Phytoseiidae) were studied during 1996–1998 in moso bamboo forests in Nanping, Fujian, China. Damage to bamboo leaves was often caused by mixed populations of the three phytophagous species, which displayed different seasonal dynamics: S. nanjingensis fed actively and reproduced in May and from late July to late October (aestivating from June to mid July), Ap. corpuzae was active and reproduced from mid July to late November, and Ac. bambusae from July to next February. During Spring S. nanjingensis was the dominant species with the greatest niche width, but in Summer Ac. bambusae and Ap. corpuzae became dominant and had greater niche widths. In Autumn, Ac. bambusae decreased but both S. nanjingensis and Ap. corpuzae mites increased and the latter became dominant. In winter all species decreased sharply in number. The two spider mite species (S. nanjingensis and Ap. corpuzae) had high niche overlaps in all four seasons. Niche overlaps between the eriophyid Ac. bambusae and the two spider mites were similarly high except during the spring when Ac. bambusae was absent. The predatory mite (T. bambusae) had higher niche overlap with Ap. corpuzae than with others during Autumn and Winter, but during Spring and Summer niche overlap was higher with S. nanjingensis.     

南京方山朴树种群结构与分布格局研究

采用相邻格子样方法对南京方山国家地质公园朴树种群结构和分布格局进行了研究。结果表明：（1）各样地朴树种群的年龄结构基本相似,Ⅰ、Ⅱ级幼苗普遍较少,幼苗贮备严重不足。种群个体分布多集中在Ⅲ级,Ⅳ级以上种群个体分布渐趋减少。（2）从静态生命表可以看出,由于Ⅰ、Ⅱ级幼苗、幼树数量偏少,导致种群Ⅰ、Ⅱ龄级的死亡率为负值,而Ⅶ、Ⅷ龄级的死亡率最大。部分龄级存在着不同程度的个体缺失,存活曲线呈明显下凹和断点波折,种群整体呈衰退趋势。（3）利用负二项参数（K）、扩散系数（C）、扩散型指数（I_δ）、Cassie指标（C_a）、丛生指数（I）、平均拥挤度指数（m^*）和聚块性指标（m^*/m）等参数对种群的空间格局进行了研究,表明朴树种群的空间分布格局为集群分布,但不同样地种群的集聚程度存在一定差异。     

Population dynamics of Panonychus osmanthi (Acari: Tetranychidae) on two Osmanthus species

Panonychus osmanthi is a non-diapausing species of spider mite that superficially resembles P. citri. It infests Osmanthus species, which are evergreen roadside and garden trees. The population dynamics of P. osmanthi were studied on Osmanthus aurantiacus and O.×fortunei during a three-year period. Seasonal changes in P. osmanthi populations were fundamentally the same in each year, although their density differed greatly from year to year. TheP. osmanthi population was bimodal, with one peak in spring (May–June) and another in winter (November–January). Populations abruptly declined after the spring peak. Predators showed a delayed density-dependent response to changes in spider mites from spring to summer, whereas in autumn and winter, predators were few because they had entered diapause. To determine the effect of predators on the rapid decline of spider mites just after the spring peak, the predators were removed by treating the trees with a synthetic pyrethroid. As a result, spider mite density did not decline after the spring peak and remained at a high level during the June-August period when spider mite density is usually very low. This suggests that predators play an important role in the drastic decline of P. osmanthi density just after the spring peak. This revised version was published online in July 2006 with corrections to the Cover Date.