对桉树枝瘿姬小蜂不同抗性的3个桉树品种枝叶挥发物分析

为了探明不同抗感桉树枝瘿姬小蜂桉树品种(系)挥发物化学成分及其含量的差异,运用气相色谱-质谱联用技术(GC-MS)对不同抗性的3个桉树品种(系)的枝叶进行化学成分分析。分别从高感虫品种201-2、高抗虫品种广1和稍感虫品种雷11的嫩叶中检测到20,22和25种化学成分,其中相对含量超过0.5%的主要化学成分分别有9,8和13种,分别占挥发物总量的82.36%,60.31%和60.79%;3个桉树种挥发物含有8种共同成分;201-2、广1和雷11特有成分分别有12,7和12种,分别占总含量的14.24%,2.1%和13.29%。结果表明,对桉树枝瘿姬小蜂不同抗性的3个桉树品种挥发物具有较大差别。     

桉树枝瘿姬小蜂对不同桉树品系及颜色的选择

在室内条件下,研究桉树枝瘿姬小蜂Leptocybeinvasa雌成虫对不同桉树品种（系）气味及颜色的行为趋性,并在室外条件下研究了该虫对各桉树品个（系）产卵选择情况。结果表明：①桉树枝瘿姬小蜂对13个桉树品种（系）挥发性气味的趋性存在明显的差异,其中对10个品种（系）有不同程度的正趋性,尤其是对尾赤桉Eucalyptusuro—phlla×E．camaldalensisDH201．2的趋性最强,而对韦赤桉E．wetareusis×Ecamaldulensis GL3和大花序桉Ecloeziana则表现出负趋性或不选择性;②不同色卡对桉树枝瘿姬小蜂的引诱效果差异明显,其中纯白色（RAL9010）和信号黄（RAL1003）引诱效果较好,选择系数分别为0．29和0．28;⑧不同桉树品种（系）上的桉树枝瘿姬小蜂产卵刻痕数明显不同,每叶平均产卵刻痕数由大到小依次为尾赤桉DH201—2,巨桉EgrandisQG3,尾巨按Europhyllax E．grandisDH32—29,尾叶桉Europhylla U6,巨尾桉EgrandisxE．urophyllaGL9,尾巨桉DH32_26,邓恩桉Edunnii,尾巨桉DH32．28,尾细桉E．urophyllaxE．tereticornisM1,柳桉E．saligna,巨桉JG1。其中尾赤按DH201—2上的产卵刻痕数明显大于其他品种（系）,而韦赤桉GL3和大花序桉2个品种上没有发现产卵刻痕。     

桉树枝瘿姬小蜂与寄主及寄生蜂体内细菌相似性研究

【目的】研究桉树枝瘿姬小蜂、寄主桉树及其天敌孟氏胯姬小蜂三者体内细菌的相似性,明确内生细菌在桉树枝瘿姬小蜂入侵过程中的作用,为桉树枝瘿姬小蜂入侵和爆发机制研究提供参考。【方法】以巨园桉DH201-2叶柄和叶脉,无羽化孔虫瘿组织,南宁桉树枝瘿姬小蜂幼虫和雌成虫,四川桉树枝瘿姬小蜂雌成虫和孟氏胯姬小蜂成虫为材料,利用Illumina HiSeq 2500平台进行高通量测序方法,对桉树枝瘿姬小蜂、寄主桉树及其天敌孟氏胯姬小蜂三者体内细菌的多样性进行比较分析。【结果】在桉树枝瘿姬小蜂、寄主桉树及其天敌孟氏胯姬小蜂三者体内共发现24个门,55个纲,126个目,225个科和497个属的细菌。Alpha多样性分析表明,巨园桉DH201-2和无羽化孔虫瘿组织体内细菌的丰富度和多样性最高;桉树枝瘿姬小蜂幼虫和成虫体内菌群具有一定的相似性;桉树枝瘿姬小蜂成虫体内菌群组成与孟氏胯姬小蜂成虫体内菌群组成相似。变形菌门（Proteobacteria）是所有样本的优势菌门;甲基杆菌属（Methylbacillus）为巨园桉DH201-2的优势菌属,链球菌属（Streptococcus）为无羽化孔虫瘿组织内生菌的优势菌属,立克次氏体（Rickettsia）为桉树枝瘿姬小蜂幼虫,成虫和孟氏胯姬小蜂成虫内生菌的优势菌属。【结论】桉树、桉树枝瘿姬小蜂和孟氏胯姬小蜂三者体内细菌具有一定相似性,表明三者在共有细菌之间具有密切联系。     

Screening of 19 genotypes of Eucalyptus spp. Against gall wasp (Leptocybe invasa) in North-western India

The present study was carried out at Punjab Agricultural University,Ludhiana,India.Nineteen clones of Eucalyptus spp.were evaluated for tolerance to gall wasp.The total number of galls per plant were recorded at 1 month after planting(MAP) and the number of galls per branch were recorded at 4 and 7 MAP.Gall wasp incidence(number of galls) was recorded on a whole plant basis during the seedling stage and the number of galls were recorded from the upper,middle and lower crown places at 4 and 7 MAP.Categorization was done on the basis of relative gall-wasp damage by keeping in view the total number of galls per plant and branch(leaves and petiole).No clone was found free from gall damage.Clones C-526,P-23 and P-103 were the least attacked by the gall wasp.Incidence as indicated by number of galls caused by Leptocybe invasa on eucalypts was higher in March than in December.     

广西博白桉树枝瘿姬小蜂生物学特性研究

通过野外调查和室内饲养观察,对桉树枝瘿姬小蜂的成虫羽化、生活史、越冬情况、年虫口变化、生活习性等生物学特性进行了初步研究。该虫在广西博白1 a发生4～5代,世代重叠,以4～5代虫瘿(含各种虫态)越冬,3—7月为成虫羽化高峰和扩散期,全年大部分时间均有成虫羽化。     

桉树枝瘿姬小蜂对苗圃不同枝树品系袋苗的感虫性测定

选择目前广东省推广面积较大的12种桉树品系袋苗,进行桉树枝瘿姬小蜂感虫性的选择性测定和强迫性测定.结果表明DH201-2虫瘿数量极显著高于其它桉树品系,广林9、32-29、W5、雷林11、广州1号、184、186、雷林17、U6、石岭1号和邓恩桉桉树品系之间差异未达到显著.     

不同抗虫品系桉树叶片背面组织的电镜观察

应用电子扫描显微镜对不同抗虫品系桉树叶片的下表皮进行观察,结果表明:在健康的桉树叶片中,气孔的长度与抗虫呈负相关,灰度值与抗虫性存在一定关系。在受害植株中,中感品系受害叶片的气孔长度极显著大于未受害叶片,而高感品系则有缓慢缩小的趋势。受害后的叶片背面,气孔密度都略有减少,邓恩桉表现为极显著变化,巨桉QG8和巨圆桉DH201-2的变化不显著。蜡质的堆积圈的相对高度,在受害后都减低。在未受害叶片中,高抗、高感品系密被蜡质;高抗品系主脉细胞细长,主脉由粗短细胞组成;中感品系的蜡质呈薄膜状。高感品系植株的受害叶片气孔周围的蜡质晶体呈熔融状态,覆盖了部分气孔面积,受害主脉粗短,叶缘界限不清晰。中感品系的蜡质则向外熔融扩散,增大了气孔的裸露,主脉细胞融合,叶缘有沉淀物。研究结果表明,叶片的气孔长度短,主脉细胞细长的品系抗虫性较强。     

桉树枝瘿姬小蜂发育起点温度与有效积温的研究

文章通过人工接种和连续跟踪调查,对桉树枝瘿姬小蜂的发育历期、发育起点温度和有效积温进行了研究.结果表明,在20.5 ～28.6 ℃之间,随着温度的升高,发育历期缩短;桉树枝瘿姬小蜂的成虫、虫瘿和世代的发育起点温度分别为10.79,10.25,10.21℃,有效积温分别为53.42,749.73,811.75 d·℃.该虫在广西壮族自治区南宁市2009年发生代数的理论值为5.23代,与实际观察结果一致.     

Impact of Eucalyptus gall wasp,Leptocybe invasa infestation on growth and biomass production of Eucalyptus grandis and E. saligna seedlings in Tanzania

A study was carried out to determine the impact of Leptocybe invasa infestation on growth and biomass production of Eucalyptus grandis W. Hill ex Maiden and E. saligna Smith seedlings in Tanzania. Three- month old seedlings were infested with L. invasa. Twenty two weeks post infestation, heights of infested E. grandis seedlings were reduced by 39.6%, while diameters were reduced by 11.3% compared to uninfested seedlings. On the other hand, the heights of infested E. saligna seedlings were reduced by 38.2% and diameters were reduced 7.7% compared to uninfested seedlings. Dry weight biomass reduction of infested seedlings was significantly higher on stem and leaves than roots and branches of both E. grandis and E. saligna. The impact of L. invasa infestation on growth and biomass production was higher in E. grandis than E. saligna. Prevention and control of L. invasa infestation should be given priority. Similar future trials should examine other commercially grown Eucalyptus species in Tanzania.     

基于模糊综合评价法的桉树枝瘿姬小蜂虫害风险评估研究

为满足决策支持系统对桉树枝瘿姬小蜂虫害风险评估及获取量化结果的需要,根据已知桉树枝瘿姬小蜂生物学性状和传播规律,建立了桉树枝瘿姬小蜂虫害风险模糊评价体系,提出了基于模糊综合评价的虫害风险评估方法。利用该方法对广西黄冕林场一新增桉树项目进行了虫害风险评估,并分析了不同虫害预防措施的效果,所得结果与事实吻合。这表明,该方法是一种有效的桉树枝瘿姬小蜂虫害风险评估方法。