沙棘木蠹蛾卵和幼虫空间分布的地统计学分析

沙棘木蠹蛾(H olcocerushippophaecolus Hua,Chou ,Fang et Chen)是近几年在内蒙古、辽宁、山西、宁夏和陕西等地大面积爆发的一种钻蛀性害虫,其危害发生在幼虫期,主要危害沙棘(H ippophae rhamnoidea)的根干部。为了有效地控制其危害,深入了解种群的空间结构,利用地统计学方法分析了两种受害程度不同的林分内沙棘木蠹蛾幼虫种群和重度受害林分内卵块的空间分布特性。结果表明:两种受害程度不同的林分内,沙棘木蠹蛾的危害具有显著差异,轻度受害林分内无虫样本所占的比例较大,达70 % ,而重度受害林分内不到2 0 % ;虫口密度在轻度受害林分内超过6头/株的只有6 .9% ,而重度受害林分内高达31.9%。根据全方向的变异函数曲线图分析得知:重度受害林分和轻度受害林分内幼虫种群的空间依赖范围分别为7.3m和87.4 18m,而局部空间连续性强度分别为0 .914和0 .178。重度受害林分内幼虫表现较强的空间聚集性,而轻度受害林分则表现为随机分布。在重度受害林分中,单株沙棘树上沙棘木蠹蛾卵块数量最多的为11个,最少的为1个,有卵株率达72 %。分别采用四种不同的理论模型来拟合卵块的实际变异曲线图,得知其全方向的变异函数曲线为指数型,空间依赖范围大小为3.6 m,局部空间连续性强度为0 .876 ,卵块在重度受害林分中呈现较强     

沙棘木蠹蛾的幼虫空间分布与抽样技术

利用常用的聚集度指标 ,对沙棘木蠹蛾HolcocerushippophaecolusHua ,Chou ,FangetChen幼虫的分布进行了分析。结果显示 ,该幼虫的空间分布格局为聚集型分布。通过Iwao的m - x回归检验方程 ,确定了其最适抽样数和最佳样方大小。采用对角线、之字型、五点式、棋盘式和平行线等 5种抽样方法对沙棘木蠹蛾幼虫的抽样技术分别进行了研究 ,结果表明 :最佳的抽样方法为棋盘式。     

沙棘木蠹蛾成虫种群发生动态与性诱剂诱捕剂监测技术

【目的】沙棘木蠹蛾Eogystia hippophaecolus(Hua,Chou,Fang et Chen)是严重危害沙棘林的重大钻蛀性害虫。在辽宁建平,4年1代,幼虫16龄。本试验旨在研究辽宁建平沙棘木蠹蛾的成虫发生规律,明确其幼虫虫口数量与成虫诱捕量之间的关系,为建立基于"3S"和昆虫性信息素诱捕耦合的虫灾监测技术提供基础数据。【方法】于栽植的健康沙棘根部接入不同虫龄的幼虫,统计可发育为老熟幼虫,入土化蛹并羽化为成虫的幼虫龄期范围。设定样地,采用随机抽样法调查各样地幼虫数量并悬挂性信息素诱捕器对成虫进行监测。将成虫诱捕量与不同龄期范围的幼虫数量进行曲线回归分析,获得监测林间幼虫数量的最优模型。【结果】5月下旬时已达12~16龄的幼虫均可在当年发育为老熟幼虫,入土化蛹并羽化为成虫。沙棘木蠹蛾在辽宁建平经历3个羽化高峰,在不同乡镇,其成虫期长短有较大差别(76~95 d不等)。当年13~16龄幼虫数量与成虫诱捕量的二次函数拟合效果最佳,即y=0.001x2+0.321x+38.783,R2=0.649,P0.05。【结论】明确了沙棘木蠹蛾幼虫在辽宁建平当年可入土化蛹并羽化为成虫的龄期范围,确定了其在3个试验地的成虫期和羽化高峰,构建了通过性信息素诱捕成虫以监测林间幼虫虫口数量的数学模型,为航空、航天遥感的虫灾监测提供技术支撑。     

沙棘主要蛀干害虫种群生态位

沙棘木蠹蛾(H olcocerus h ipp ophaecolusHua,Chou,F ang et Chen)是近几年在我国内蒙古、辽宁、山西、宁夏、陕西和甘肃等地大面积爆发的一种钻蛀性害虫,主要以幼虫危害沙棘(H ipp ophae rham noid ea)的根部和干部。在宁夏,沙棘除受到沙棘木蠹蛾的危害,还受到红缘天牛(A sias ha lod end ri Pa llas)的严重危害,该虫主要危害沙棘的干部。作者根据种群生态位理论,从时间、空间等资源利用上,定量地描述了沙棘木蠹蛾与红缘天牛种群之间的联系和竞争共存机制,结果表明:沙棘木蠹蛾幼虫主要分布在根部和干部80~120cm的范围内,不同时期,幼虫具有从干部向根部转移危害的习性;而红缘天牛主要分布在干部40~120cm的范围内,不同时期,幼虫没有转移危害的习性。沙棘木蠹蛾和红缘天牛的时间生态位和空间生态位宽度均较大,发生期较长,在沙棘上的活动范围较广,而不同时期内沙棘木蠹蛾的空间生态位宽度变动较红缘天牛大,其在沙棘上的活动范围在不同时期有较大的变动,而红缘天牛则较小。空间生态位重叠较小,在沙棘上的分布趋于分离,对空间资源的需求具有较大的差异,而时间生态位重叠较大,在沙棘的生长季节均能同时危害,危害期长但不具有明显的危害高峰期。两种害虫在空间生态位上的种间竞争强度较小,而在时间生态位上的种间竞争强度较大,在整个发生期内,两种害虫均能同时危害沙棘,但其位置有较大差异,在沙棘根部和干部40cm范围内,两种害虫几乎不能共存。     

沙棘木蠹蛾的人工饲养

采用A、B和C 3种饲料饲养沙棘木蠹蛾Holcocerushippophaecolus,A饲料成分为水、玉米粉、豆粉、蔗糖、琼脂、酵母粉、山梨酸钾、对羟基苯甲酸甲酯 ;B饲料成分为水、玉米粉、豆粉、琼脂、酵母粉、抗坏血酸、苯甲酸钠 ;C饲料成分为大豆粉、沙棘木粉、蔗糖、琼脂、维生素混合液、酵母浸粉、抗坏血酸、防腐剂混合液、无机盐。其中 ,B饲料防腐能力较差 ,饲养 1 2周后放弃。A和C 2种饲料能使沙棘木蠹蛾幼虫体重持续增长 ,饲养前期A饲料平均体重增量是C饲料的 1 6倍 ,A和C 2种饲料化蛹率分别为83. 3 %和 66. 7% ,羽化率分别为 3 0 % ,1. 6 7%。选择在沙土中结茧化蛹 ,能显著提高饲养成功率。     

性诱剂在沙棘木蠹蛾监测和控制中的应用

利用性诱剂在全国7个省9个地区对沙棘木蠹蛾Holcocerus hippophaecolus Hua,Chou,Fang etChen进行连续3年的野外监测和控制,结果表明：沙棘木蠹蛾性诱剂具有较好的野外监测和诱集效果,其中,平均诱蛾量最高的达26.6头/诱捕器,日诱蛾量最高的为45.9头/d,诱捕器之间的最佳设置距离为120 m,诱捕效率达50%以上。沙棘木蠹蛾性诱剂已成为沙棘木蠹蛾控制中最重要的措施之一,具有广阔的推广应用前景。     

沙棘木蠹蛾幼虫龄期的初步研究

通过测量沙棘木蠹蛾Holcocerus hippophaecolusHua,Chou,FangetChen幼虫的头壳宽、体长、体宽、上颚长和宽等指标,确定其幼虫共有16龄,不同龄幼虫的头壳宽值符合Dyar氏发现的幼虫头壳宽增长规律。同时,探讨了不同龄幼虫的臀足趾钩数、前胸侧毛L1、L2和L3以及腹足大小等指标之间的关系,结果表明:除臀足趾钩数在不同龄幼虫间的数量变化无明显规律,无法用于幼虫的龄期划分外,其它指标均呈现较明显的线性回归关系,初步判断,这些指标可以用于沙棘木蠹蛾不同龄期幼虫的划分。     

芦笋木蠹蛾的生物学特性

芦笋木蠹蛾Isoceras sibirica(Alpheraky)是危害芦笋的重要害虫。该虫在山西省运城市1年发生1代,以老熟幼虫在土中结薄茧越冬。翌年3~4月老熟幼虫由深土层上移至地表土壤结茧化蛹。4月中下旬为化蛹高峰。5月上中旬为蛹羽化高峰期。6月上旬为卵孵化高峰期。幼虫为害期为5月下旬至10月下旬。对该虫的形态、生活习性和发生规律作了描述和报道。     

小线角木蠹蛾幼虫适应不同寄主的转录组学分析

【目的】通过比较小线角木蠹蛾Streltzoviella insularis Staudinger幼虫取食不同寄主后的肠道转录组,旨在挖掘幼虫对寄主适应的相关基因,为探究小线角木蠹蛾幼虫对寄主的适应机制提供分子生物学数据。【方法】采用Illumina二代测序技术,测定小线角木蠹蛾幼虫取食3种不同寄主树种（洋白蜡、银杏和国槐）15 d后的肠道转录组,使用BLAST软件对unigene序列进行GO和KEGG富集,通过比较分析筛选出幼虫对寄主适应的相关基因。【结果】取食国槐与取食洋白蜡的小线角木蠹蛾幼虫的差异表达基因数量有916个,取食银杏与取食洋白蜡的小线角木蠹蛾幼虫的差异表达基因数量为1 163个,取食银杏与国槐的小线角木蠹蛾幼虫的差异表达基因数量为1 621个;其中,上调表达的差异基因与解毒代谢、水解酶和转运蛋白等密切相关;取食不同寄主的幼虫肠道差异基因中,解毒酶（17个）和消化酶（20个）的差异基因数量都明显多于保护酶（5个）。本研究筛选出2个解毒酶基因、3个消化酶基因和1个保护酶基因,可作为小线角木蠹蛾幼虫对寄主适应机制的重点研究对象。【结论】本研究初步揭示了小线角木蠹蛾幼虫响应不同寄主的差异表达基因,为进一步探究小线角木蠹蛾对寄主的适应机制提供了基础依据。     

脐腹小蠹形态特征和生物学特性

脐腹小蠹Scolytus schevyrewi Seme.是榆树的一种重要蛀干害虫。本研究在宁夏盐池县通过室内观察和林间调查相结合,研究了脐腹小蠹的形态特征及其生活史、成虫寿命、习性、交尾行为等生物学特性。结果显示:脐腹小蠹虫在宁夏盐池县一年发生2代,以老熟幼虫或蛹越冬,老熟幼虫约占98.2%,蛹约占1.8%。越冬幼虫于5月上旬开始化蛹,5月中旬为化蛹盛期,5月下旬开始羽化,6月上旬为羽化盛期。第2代幼虫于6月底、7月初开始化蛹,7月下旬达羽化盛期,8月上旬羽化结束;脐腹小蠹雌成虫平均寿命为(27.14±3.74)d,雄成虫的平均寿命为(16.86±4.13)d,差异显著(P<0.05);此外,脐腹小蠹无滞育现象;脐腹小蠹的4种天敌,分别是榆小蠹长茧蜂Elachistocontrum sp.、虱形螨Pedieuloids ventricosus Newport、拟截斑郭公虫Thansimus sp.和蠼螋Labidura sp.。     

Spatial distribution of Holcocerus hippophaecolus (Lepidopetera: Cossidae) pupae in a seabuckthorn (Hippophae rhamnoides) stand.

The seabuckthorn carpenter moth,Holcocerus hippophaecolus,which has a generation time of four years,is recently becoming one of the major pests of the seabuckthorn (Hippophae rhamnoides) in Inner Mongolia,Liaoning,Shanxi,Ningxia and Shaanxi of China (Hua et al.,1990).The larvae of the H.hippophaecolus mainly damage the stems and roots of the seabuckthorn,and the mature larvae pupate in the soil.The spatial distribution of the pupae was analyzed by using biostatistics and geostatistics in order to effectively control the insect and further study the spatial distribution of the population.Results show that most of the pupae (90%) had an eclosion time span from early June to the end of July.The sex ratio of the pupae was nearly 1:1 in the woodland samples.In addition,24.3% of the 971 trees investigated had pupae and it ranged from 0 to 4 per tree within a distance of 1.3 m from the base of the stem.90% of the pupae were aggregated within a distance of 1 m from the base of the stem.The pupae show intense spatial aggregation in the sampled woodland which had an 11.1 m spatial dependence and a 90.7% intensity in the local spatial continuity.Moreover,the population presented an intensive spotted distribution and many aggregated spots were found in the woodlands.As for the relationship between grid size and variogram of the pupae,the variations in the range,the intensity of local spatial continuity and the sill were all very low or non-existent when the grid size was 5 m,6 m or 7 m.Whereas,the value of the decisive coefficient was the biggest when the grid size was 5 m making it the ideal grid size.     

Spatial distribution of Holcocerus hippophaecolus (Lepidoptera: Cossidae) pupae in a seabuckthorn (Hippophae rhamnoides) stand

The seabuckthorn carpenter moth, Holcocerus hippophaecolus, which has a generation time of four years, is recently becoming one of the major pests of the seabuckthorn (Hippophae rhamnoides) in Inner Mongolia, Liaoning, Shanxi, Ningxia and Shaanxi of China (Hua et al., 1990). The larvae of the H. hippophaecolus mainly damage the stems and roots of the seabuckthorn, and the mature larvae pupate in the soil. The spatial distribution of the pupae was analyzed by using biostatistics and geostatistics in order to effectively control the insect and further study the spatial distribution of the population. Results show that most of the pupae (90%) had an eclosion time span from early June to the end of July. The sex ratio of the pupae was nearly 1:1 in the woodland samples. In addition, 24.3% of the 971 trees investigated had pupae and it ranged from 0 to 4 per tree within a distance of 1.3 m from the base of the stem. 90% of the pupae were aggregated within a distance of 1 m from the base of the stem. The pupae show intense spatial aggregation in the sampled woodland which had an 11.1 m spatial dependence and a 90.7% intensity in the local spatial continuity. Moreover, the population presented an intensive spotted distribution and many aggregated spots were found in the woodlands. As for the relationship between grid size and variogram of the pupae, the variations in the range, the intensity of local spatial continuity and the sill were all very low or non-existent when the grid size was 5 m, 6 m or 7 m. Whereas, the value of the decisive coefficient was the biggest when the grid size was 5 m making it the ideal grid size.     

Spatial distribution of Holcocerus hippophaecolus (Lepidoptera: Cossidae) pupae in a seabuckthorn (Hippophae rhamnoides) stand

The seabuckthorn carpenter moth, Holcocerus hippophaecolus, which has a generation time of four years, is recently becoming one of the major pests of the seabuckthorn (Hippophae rhamnoides) in Inner Mongolia, Liaoning, Shanxi, Ningxia and Shaanxi of China (Hua et al., 1990). The larvae of the H. hippophaecolus mainly damage the stems and roots of the seabuckthorn, and the mature larvae pupate in the soil. The spatial distribution of the pupae was analyzed by using biostatistics and geostatistics in order to effectively control the insect and further study the spatial distribution of the population. Results show that most of the pupae (90%) had an eclosion time span from early June to the end of July. The sex ratio of the pupae was nearly 1:1 in the woodland samples. In addition, 24.3% of the 971 trees investigated had pupae and it ranged from 0 to 4 per tree within a distance of 1.3 m from the base of the stem. 90% of the pupae were aggregated within a distance of 1 m from the base of the stem. The pupae show intense spatial aggregation in the sampled woodland which had an 11.1 m spatial dependence and a 90.7% intensity in the local spatial continuity. Moreover, the population presented an intensive spotted distribution and many aggregated spots were found in the woodlands. As for the relationship between grid size and variogram of the pupae, the variations in the range, the intensity of local spatial continuity and the sill were all very low or non-existent when the grid size was 5 m, 6 m or 7 m. Whereas, the value of the decisive coefficient was the biggest when the grid size was 5 m making it the ideal grid size. __________ Translated from Acta Ecologica Sinica, 2006, 26(10): 3232–3237 [译自: 生态学报]     

Genetic structure in the seabuckthorn carpenter moth (Holcocerus hippophaecolus) in China: the role of outbreak events, geographical and host factors

Understanding factors responsible for structuring genetic diversity is of fundamental importance in evolutionary biology. The seabuckthorn carpenter moth (Holcocerus hippophaecolus Hua) is a native species throughout the north of China and is considered the main threat to seabuckthorn, Hippophae rhamnoides L. We assessed the influence of outbreaks, environmental factors and host species in shaping the genetic variation and structure of H. hippophaecolus by using Amplified Fragment Length Polymorphism (AFLP) markers. We rejected the hypothesis that outbreak-associated genetic divergence exist, as evidenced by genetic clusters containing a combination of populations from historical outbreak areas, as well as non-outbreak areas. Although a small number of markers (4 of 933 loci) were identified as candidates under selection in response to population densities. H. hippophaecolus also did not follow an isolation-by-distance pattern. We rejected the hypothesis that outbreak and drought events were driving the genetic structure of H. hippophaecolus. Rather, the genetic structure appears to be influenced by various confounding bio-geographical factors. There were detectable genetic differences between H. hippophaecolus occupying different host trees from within the same geographic location. Host-associated genetic divergence should be confirmed by further investigation.     

褐梗天牛幼虫和成虫空间分布的地统计学研究

褐梗天牛(Arhopalus rusticus Linnaeus)是一种对松、杉、柏等林木危害非常严重的蛀干害虫,主要危害针叶树的衰弱木以及火灾后的枯立木,是继松褐天牛之后携带拟松材线虫能力最强的蛀干害虫。为了更好地控制其危害,深入地研究其种群空间格局,运用地统计学方法分析了3块受害程度不同的油松林内褐梗天牛幼虫和成虫的空间分布特性。结果表明:3种受害程度不同的林分内,褐梗天牛的危害具有显著差异,轻度受害林分内有虫株率为30.8%,中度受害林分内有虫株率为44.3%,而重度受害林分内高达78.3%。根据变异函数曲线图分析得知:轻度受害林、中度受害林和重度受害林内褐梗天牛幼虫种群空间分布最优拟合模型分别为高斯模型、高斯模型和指数模型,成虫的种群空间分布最优拟合模型均为线性模型。在3种林分中褐梗天牛幼虫数量具有明显的空间依赖性,轻度受害林、中度受害林和重度受害林内幼虫数量的空间依赖范围分别是19.10、11.97、61.98m,其空间连续性强度分别是0.646、0.784和0.500;成虫的空间依赖范围分别是43.08、43.23、44.17m,其空间连续性强度分别是0.044、0.021和0.171,但其成虫的数量在空间呈随机分布,没有表现出空间依赖性。根据垂直分布图分析得出:褐梗天牛幼虫和成虫在油松上主要集中聚集在某个高,然后随着高度增加密度降低,随着高度接近地面密度也降低。用Kriging插值法生成的空间分布图显示幼虫在空间分布上具有明显的聚集性,其聚集中心主要集中在林地中心,由林地中心株向整个林地扩散,而成虫则表现为随机分布。     

The arrangement of resources in patchy landscapes: effects on distribution, survival, and resource acquisition of chironomids

The spatial arrangement of resources in patchy habitats influences the distribution of individuals and their ability to acquire resources. We used Chironomus riparius, a ubiquitous aquatic insect that uses leaf particles as an important resource, to ask how the dispersion of resource patches influences the distribution and resource acquisition of mobile individuals in patchy landscapes. Two experiments were conducted in replicated laboratory landscapes (38×38 cm) created by arranging sand and leaf patches in a 5×5 grid so that the leaf patches were either aggregated or uniformly dispersed in the grid. One-day-old C. riparius larvae were introduced into the landscapes in one of three densities (low, medium, high). In experiment 1, we sampled larvae and pupae by coring each patch in each landscape 3, 6, 12, or 24 days after adding larvae. In experiment 2, emerging adults were collected daily for 42 days from each patch in each landscape. In aggregated landscapes, individuals were aggregated in one patch type or the other during a particular developmental stage, but the ”preferred” type changed depending on developmental stage and initial density. Adult emergence was lower by about 30% in all aggregated landscapes. In dispersed landscapes, individuals used both types of patch throughout their life cycles at all initial densities. Thus, patch arrangement influences the distribution of mobile individuals in landscapes, and it influences resource acquisition even when average resource abundance is identical among landscapes. Regardless of patch arrangement, high initial density caused accumulation of early instars in edge patches, 75% mortality of early instars, a 25% increase in development time, and a 60% reduction in adult emergence. Because mortality was extremely high among early-instar larvae in high-density treatments, we do not have direct evidence that the mechanism by which patch arrangement operates is density dependent. However, the results of our experiments strongly suggest that dispersion of resource patches across a landscape reduces local densities by making non-resource patches available for use, thereby reducing intraspecific competition. Received: 20 July 1999 / Accepted: 28 January 2000     

Parasitoid complex of the bird cherry ermine moth Yponomeuta evonymellus in Korea

The parasitoid complex of Yponomeuta evonymellus L. (Lepidoptera: Yponomeutidae), the bird cherry ermine moth (BCEM), was sought in South Korea with the goal of identifying its potential biological controls. Thirteen primary and two secondary parasitoids were found. Diadegma armillatum (Grav.), Herpestomus brunnicornis Grav. (Icheumonidae), and Zenillia dolosa (Meigen) (Tachinidae) were the most important parasitoids causing 3.5%, 7.1%, and 7.7% of the combined parasitism of the host larvae and pupae, respectively. The composition of parasitoid species was more diverse in larvae than in pupae; 10 species were reared from larvae, compared to six from pupae. The parasitoid complex contributed to the relatively low mortality levels of Yponomeuta evonymellus with the combined total rate of parasitism of 29.6% for the host larvae and pupae. This level is below that found in some European populations (50%) and is not greater than the larval rate of parasitism (31%) found in the congeneric apple ermine moth in Korea. This low rate of parasitism is partly attributed to the parasitism by Ageniaspis fuscicollis (1%) detected in Yponomeuta evonymellus, which is similar to that detected in Yponomeuta evonymellus in European reports. This is the first report of the parasitoid complex attacking the BCEM in Korea.