新入侵害虫--刺桐姬小蜂

刺桐姬小蜂Quadrastichus erythrinae Kim是一种新入侵害虫,近两年来,该虫陆续在中国台湾和美国夏威夷等地发生.2005年7月,深圳出入境检验检疫局在广东省深圳市某景区的杂色刺桐上首次发现刺桐姬小蜂.为了防止疫情扩散,农业部、国家林业局和国家质检总局联合发布公告,将刺桐姬小蜂列为我国进境植物检疫性和林业检疫性有害生物.     

深圳刺桐姬小蜂的发生与为害

刺桐姬小蜂（Quadrastichus eryhrinae Kim）2005年7月在深圳首次发现。2005年8月，农业部、国家林业局和国家质检总局联合发布第538号公告，将刺桐姬小蜂列为中华人民共和国进境植物检疫有害生物和全国林业检疫性有害生物，并采取限制刺桐植物进口和检疫控制措施。因此，深圳市有关部门组织开展了全市范围的刺桐姬小蜂疫情普查和扑灭行动。     

刺桐姬小蜂危害鸡冠刺桐荚果的观察

刺桐姬小蜂能危害刺桐树的叶、叶柄、嫩芽和幼枝,作者最近观察到该虫还能危害鸡冠刺桐花和荚果.刺桐姬小蜂寄生在新抽出的花蕾和新结的幼果中,作者从荚果中找到了该虫的幼虫、蛹及正在羽化的成虫.该虫在深圳可全年发生.本文总结了受害鸡冠刺桐荚果虫瘿的种类与形成过程,指出虫瘿能导致荚果出现条形果、锤形果、打结形果、细腰形果、肿大形果等类型,并对各类型的形成过程进行分析.     

刺桐姬小蜂的防治试验

本文报道营林措施和化学药剂防治刺桐姬小蜂的试验结果,以剪除受害枝叶后钻孔施药或根埋施药的防治效果最好,防治效果达到96.0%～97.1%.单独使用树体杀虫剂的防治效果只有79.0%,单独采取剪除受害枝叶的防治效果为93.8%.     

新入侵有害生物刺桐姬小蜂初报

2005年7月25日,深圳出入境检验检疫局技术人员在深圳市日常疫情调查时发现一景区杂色刺桐（Erythrina variegata）叶片上布满虫瘿,取样送实验室检验。经对虫样检查和饲养观察,虫瘿内有大量蜂类幼虫和蛹。7月28～31日共收集到寄生蜂成虫362头。根据该虫的形态特征、寄主和危害特点,鉴定为刺桐姬小蜂（Quadrastichus erythinae Kim,英文名为erythria gall wasp,我国台湾省称为刺桐釉小蜂）,为中国大陆新纪录种。8月6日,该虫鉴定结果分别得到浙江大学和中国科学院寄生蜂专家复核确认。     

金脉刺桐嫩枝上刺桐姬小蜂虫瘿分布规律研究

刺桐姬小蜂Quadrastichus erythrinae Kim是重要外来入侵害虫,危害刺桐属多种植物。本文调查研究了金脉刺桐嫩枝上刺桐姬小蜂虫瘿的数量分布和空间格局。结果显示,金脉刺桐嫩枝上靠近生长点(芽头)一端刺桐姬小蜂虫瘿数量较多,15 cm以内占90%以上,距离越远越少,其虫瘿数量比率(Y)和枝条长度(X)关系方程为Y=72.577e-0.138X。对频次分布的分析结果显示,刺桐嫩枝上虫瘿主要以虫瘿集体形式出现。获得的虫瘿空间格局主要参数平均拥挤度M*、丛生指数I、聚块性指数M*/M等均显著大于1,表明虫瘿是聚集分布且聚集程度较强。建立的Iwao M*-M方程为M*=1.75+3.51M、Taylor幂函数法则模型为lg s2=0.554+1.828lgx珋。     

溴甲烷对刺桐姬小蜂的熏蒸效果

研究了溴甲烷熏蒸对刺桐姬小蜂的检疫处理效果。研究结果表明,刺桐姬小蜂的死亡率随熏蒸剂量增加而增高。在同一剂量处理下,虫瘿外刺桐姬小蜂的死亡率显著高于虫瘿内刺桐姬小蜂的死亡率。当熏蒸剂量≥40 g/m³时,刺桐姬小蜂幼虫、蛹和成虫均全部死亡。在推荐熏蒸剂量处理下,刺桐植株未受到不利影响。     

刺桐姬小蜂的生物学特性与检疫

本文分别介绍了刺桐姬小蜂的发生与分布以及生物学特性,着重介绍了2005年7月中国大陆(深圳)首次发现该虫后对其为害、羽化、交配与产卵、发育与致瘿、鸡冠刺桐荚果内虫瘿的形成过程、越冬习性等生物学特性进行观察与研究的结果,分析了其经济重要性,研究、提出并采取了一系列检疫扑灭措施.     

刺桐姬小蜂在中国的适生区分析

运用CLIMEX的气候相似系数法,对入侵害虫刺桐姬小蜂在中国的适生区进行了分析和预测,结果表明:中国大陆有18个省区45个市、县(地区)适合该虫生存,大体分布于18.14°N～36.00°N,98.30°E～121.36°E范围内,这些地区也是刺桐属植物的主要分布区。     

杂色刺桐叶片上刺桐姬小蜂虫瘿的分布与抽样技术

本文调查并分析了杂色刺桐(Erythrina variegata Linn.)叶片上刺桐姬小蜂(Quadrastichus erythrinae Kim)虫瘿的分布规律,结果表明:叶片上的虫瘿主要分布于靠近叶柄的主脉两侧下部区域,多以1~2个虫瘿联体的形式存在;杂色刺桐叶片上刺桐姬小蜂虫瘿呈聚集分布,分布形式为负二项分布,分布的基本成分为个体群,且个体群大小随着虫瘿密度的增加而增大;虫瘿具有密度依赖性,聚集是昆虫本身习性和环境共同引起的。根据Iwao的方法,本文还确定了虫瘿最适抽样模型和最适抽样量,并列出了序贯抽样表。     

@RISK在有害生物定量风险评估中的应用

定性风险评估和定量风险评估是有害生物风险分析的主要方法,@RISK是进行定量风险评估的重要软件工具之一。本文在回顾有害生物定性风险评估与定量风险评估概念、关系及优缺点的基础上,综合分析了国内外使用@RISK软件针对植物病原物和害虫进行定量风险评估的发展现状,并就@RISK的未来应用提出了相关建议。     

有害生物的定性与定量风险分析

本文从有害生物风险分析的历史及最新发展探讨了定性与定量有害生物风险分析的概念、关系及各自的优缺点,介绍了定量有害生物风险分析理论及其实施的过程、方法等,最后给出一个定量方法的实例：中国进口美国小麦的TCK风险分析。     

有害生物风险分析研究概述

随着世界各国间经济贸易往来的日益频繁,外来有害生物的危害也愈发严重。有害生物风险分析的开展有利于积极主动实施有害生物防控策略,保护我国农林生产、生态环境和人民健康安全,并促进对外经济贸易发展。本文概述了有害生物风险分析的基本内涵和近期国内外研究现状,对常用的有害生物风险分析研究方法进行了总结和归纳,并介绍了目前有害生物风险分析工作的研究进展。此外,本文提出了有害生物风险分析工作中存在的问题,并针对存在的问题进行了讨论。     

Susceptibility of European bread and durum wheat cultivars to Tilletia indica

Representative European wheat cultivars were tested under quarantine containment for their susceptibility to Tilletia indica, the cause of Karnal bunt of wheat. Fifteen winter and 15 spring wheat ( Triticum aestivum ) and 11 durum wheat ( Triticum durum ) cultivars were inoculated by boot injection just prior to ear emergence to test their physiological susceptibility. Selected cultivars were then re-tested by spray inoculation after ear emergence to determine their morphological susceptibility, which is a better predictor of field susceptibility. At maturity, the ears and seeds were assessed for incidence and severity of disease. For the physiological susceptibility tests, 13/15 winter wheat cultivars were infected and the percentage of infected seeds ranged from 1 to 32%. For spring cultivars, 13/15 cultivars were infected and the percentage of infected seeds ranged from 1 to 48%. For the durum cultivars, 9/11 were infected and the percentage of infected seeds ranged from 2 to 95%. Across all cultivars, 35/41 were infected. Based on historical Karnal bunt susceptibility categories using coefficients of infection, one cultivar was classed as highly susceptible, three as susceptible, 11 as moderately susceptible, 20 as resistant and only six as highly resistant. The spray-inoculation morphological susceptibility tests broadly confirmed the physiological susceptibility results, although lower levels of infection were observed. Overall, the range of susceptibility was similar to that found in cultivars grown in Karnal bunt affected countries. The results demonstrate that European wheat cultivars are susceptible to T. indica and thus could potentially support the establishment of T. indica if introduced into Europe.     

祁连山自然保护区云杉阿扁叶蜂风险评估

本文采用国内林业检疫性有害生物评估指标体系和分析方法，对祁连山自然保护区云杉阿扁叶蜂潜在的风险进行定性、定量分析与评估，结果表明，云杉阿扁叶蜂在祁连山自然保护区为中度危险性森林有害生物。     

荔枝主要害虫及其防治

荔枝的主要害虫有荔枝蝽蟓（ＴｅｓｓａｒａｔｏｍａｐａｐｉｌｌｏｓｎＤｒｕｒｙ）,荔枝蒂蛀虫（Ｃｏｎｏｐｏｍｏｒｐｈａｓｉｎｅｎｓｉｓ）荔枝龟背天牛（ＡｒｉｓｔｏｂｉａｆｅｓｔｄｏＶｏｅｔ）荔枝叶瘿纹（Ｄａｓｉｎｅｒｕｓａｐ．）荔枝瘿螨（ＥｒｉｏｐｈｙｅｓｌｉｔｃｈｉｉＫｅｉｆｅｒ）等。果农采用的防治方法包括农业防治,生物防治,化学防治等,国内外目前仍依赖化学防治,荔枝的主要害虫都有相应的重要天敌。     

我国有害生物风险分析(PRA)的历史与现状

本文回顾了中国有害生物风险分析工作将近一个世纪的历史 ,介绍了以动植物检疫实验所为主完成的 3 8个风险分析报告、繁殖材料风险分析工作进展和最近完成的小麦矮腥黑穗病菌定量风险分析 ,在总结最近 2 0年PRA工作的基础上 ,提出了我国PRA工作中存在的问题及对策     

Sweetpotato infestation by Cylas spp. in East Africa: I. Cultivar differences in field infestation and the role of plant factors

Sweetpotato weevils ( Cylas spp.) constitute a major constraint upon sweetpotato production and utilization world-wide. Attempts to breed for resistance to Cylas spp. have had limited success. However, there are reports of variation in the susceptibility to weevil attack in the field among cultivars in East Africa. Field trials were conducted at two sites (Ukiriguru and Kibaha) in Tanzania and at one site (Serere) in Uganda to determine the extent to which sweetpotato cultivars presently available in East Africa consistently differ in their susceptibility to field infestation by Cylas spp. and to identify the plant factors that determine the levels of susceptibility. Several methods to assess levels of field infestation were tested, and their relative merits are discussed. Significant cultivar differences in susceptibility to Cylas spp. infestation were observed for four out of six trials carried out over 2 years. The exceptions were cases where infestation levels were either very low or very high. Linear regression models of infestation suggest that the following plant characteristics are associated with low susceptibility to Cylas spp. infestation: increased distance of roots from the soil surface, fewer soil cracks, fewer exposed roots and a high foliage yield. Both the distance of the roots from the soil surface (shortest weevil distance) and foliage yield differ significantly between cultivars. The former cannot be approximated by measurement of root neck length, but must be measured in situ .