宁夏灵武市沟眶象发生特点

系统调查沟眶象Eucryptorrhynchus chinensis(Olivier)在宁夏灵武市的发生情况和特点发现:沟眶象以成虫和幼虫在土壤中越冬,成虫有2个发生高峰期,越冬结束后以成虫越冬的沟眶象出土出现第1个高峰期,以幼虫越冬的沟眶象经化蛹羽化出土出现第2个高峰期;幼虫危害臭椿根部形成的瘤状物可以作为鉴别沟眶象危害的特征;沟眶象幼虫在土壤中垂直分布范围集中在0～45 cm深土层,约占80%;成虫出土孔集中在距臭椿树干基部75 cm范围内,占88%。据此建议土壤施药化学防治沟眶象时,施药深度不宜低于45 cm,施药点距树干基部水平距离不得少于75 cm,且树周各个方向均需施药。每年10月末沟眶象开始"入土"、翌年4月末开始"出土",在沟眶象"入土"结束后但未冻土之前的11中旬和土壤解冻之后但尚未"出土"前的4月中旬,这两个时期土壤施药防治效果较好;防治沟眶象的同时,还应适时采取打孔注药、熏蒸等措施防治臭椿(Ailanthus altissima(Mill.)Swingle)树干内的臭椿沟眶象Eucryptorrhynchus brandti(Harold)。     

取食臭椿不同部位对沟眶象和臭椿沟眶象成虫消化解毒酶的影响

沟眶象Eucryptorrhynchus scrobiculatus和臭椿沟眶象E.brandti是取食单一寄主臭椿Ailanthus altissima不同部位的钻蛀性害虫。二者成虫羽化后交配之前均需补充营养,且取食臭椿不同部位(叶柄、1年生枝、2～3年生枝、主干)对其雌成虫生殖系统发育的影响差异显著。就臭椿沟眶象雌成虫而言,只有取食主干才能够产卵;而对沟眶象雌成虫来说,则只有取食2～3年生枝的无法产卵。本研究使用臭椿的4种不同部位(叶柄、1年生枝、2～3年生枝、主干)饲喂这两种象甲成虫,利用ELISA试剂盒测定两种象甲的3种解毒酶(谷胱甘肽转移酶、羧酸酯酶和细胞色素P450)和3种消化酶(胰蛋白酶、淀粉酶、脂肪酶)的酶活性。结果表明,两种象甲中后肠的6种酶活性在取食不同寄主部位后发生显著性差异。其中,臭椿沟眶象雌成虫取食主干显著降低其中后肠的CarE酶活性,沟眶象雌成虫取食2～3年生枝能显著提高中后肠的CarE酶活性,同时降低中后肠AMY酶活性。本文明确了寄主植物不同部位对这两种象甲成虫中后肠消化解毒酶活性的影响,分析了两种象甲初羽化雌成虫补充营养造成生殖系统发育差异的原因,对后续...     

臭椿沟眶象幼虫消化道解剖方法

臭椿沟眶象幼虫消化道柔软脆弱,尤其是1龄与2龄幼虫的消化道纤细易断,解剖难度较大。本文介绍了臭椿沟眶象幼虫消化道的具体解剖方法,根据不同龄期幼虫脂肪含量与消化道韧性差异,对1-2龄和3-7龄幼虫,分别使用纵切法和剥离法解剖。结果表明:臭椿沟眶象幼虫消化道分为前肠、中肠和后肠。前肠为窄而细的管状,没有明显的嗉囊和前胃。中肠分为2部分,前部膨大,后部为光滑的管状。后肠由回肠和直肠组成。马氏管6根。这两个方法提高了此幼虫消化道解剖的效率与成功率,希望能为具有体壁柔软、消化道脆弱易损等特点昆虫幼虫的消化道解剖提供借鉴与参考。     

沟眶象触角感器的扫描电镜观察

应用扫描电镜观察沟眶象触角感器的类型、数量和分布。结果表明,沟眶象触角上共有5类10种感器,分别为4种锥形感器、2种刺形感器、2种毛形感器、1种栓锥形感器和1种柱形感器。根据感器的分布、形态特征结合已有的文献描述,推测了感器可能的功能。触角感器在每节上的数量和分布不同,在背腹面的分布差异不显著。雌雄成虫触角上感器总的数量存在显著差异。     

臭椿沟眶象成虫越冬场所选择的关键因子

昆虫成虫越冬前会选择合适的越冬场所,为了更好地控制臭椿沟眶象Eucryptorrhynchus brandti(Harold)成虫,需要了解其越冬场所的特点,找出影响其越冬场所选择的关键因素,以便开展越冬场所管理和翌年发生预测。在宁夏臭椿沟眶象发生区,采用平行线取样方法中的随机调查法调查臭椿沟眶象越冬场所(寄主、寄主树下植被、土壤温湿度)、越冬的树干方位、越冬位置距树干距离等情况。用皮尔逊相关性与多元统计分析方法确定影响其越冬的主要因素为胸径(X_1)、流胶孔数(X_2)、羽化孔数(X_2)、土壤湿度(X_3)、越冬土壤深度(X_5)、越冬树干方位(X_7)对臭椿沟眶象越冬成虫数量有显著影响(P≤0.05),建立的多元回归模型为Y=-26.267+0.258X_1-1.138X_2+5.276X_3+0.824X_5+20.191X_7-0.707X_(10),R~2=0.586,正判率为63.4%。对越冬成虫数量的实测值与预估值进行t-检验,发现预估值与实测值之间无显著差异(P=0.103≥0.05)。建立的多元回归模型,能够预测翌年害虫发生情况,利用其选择越冬场所的特点,为开展臭椿沟眶象潜所诱杀提供理论依据。     

基于沟眶象属两近缘种不同虫态转录组的气味受体基因鉴定及表达分析

[目的]基于沟眶象属Eucryptorrhynchus两近缘种沟眶象E.scrobiculatus和臭椿沟眶象E.brandti不同虫态的转录组数据进行气味受体(odorant receptor,OR)基因的鉴定及表达特征分析,补充两种象甲的气味受体信息,为之后的功能研究提供理论依据.[方法]从沟眶象(幼虫、蛹和成虫)...     

沟眶象

<正>沟眶象为鞘翅目Coleoptera象虫科Curculionidae昆虫。分布在北京、天津、山东、河北、河南、江苏、陕西、辽宁、甘肃、四川等地,危害臭椿、千头椿等。成虫体长18.5 mm,略发光,前胸、鞘翅基部的大部分及鞘翅端部1/3处密被乳白色和赭色鳞片,额略窄于喙基部,喙的中隆线两侧各有两个明显的沟。成虫以嫩梢、叶片、叶柄为食,造成树木折枝、伤叶、皮层损坏;幼虫咬食皮层,随     

三种杀虫剂对昆虫病原线虫侵染臭椿沟眶象幼虫能力的影响

昆虫病原线虫在20世纪初后已发展成为生物防治领域研究热点之一,作为生防制剂被广泛使用,且可与杀虫剂混用.臭椿沟眶象Eucryptorrhynchus brandti是重要的林木蛀干害虫,对宁夏农田防护林主要树种臭椿Ailanthus altissima造成严重危害.目前臭椿沟眶象的主要防治方法之一是化学防治,但效果不理...     

沟眶象转录组微卫星特征分析

本研究基于高通量测序获得的沟眶象Eucryptorrhynchus chinensis(Olivier)转录组数据,采用MISA(Micro Satellite)软件对其简单序列重复(simple sequence repeat,SSR)位点进行了高通量发掘。对筛选得到的1 kb以上的Unigene(17590条,占Unigene总数的26.98%)进行了SSR分析,结果发现含SSR的序列有1665条,共发现1823个SSR,平均32.52 kb出现一个SSR。沟眶象微卫星主要以三碱基重复类型为主(637,34.94%),其次为单碱基重复(576,31.60%)。共发现104种碱基重复基元,所占比例最高的为(A/T)n(30.39%),其次为(AT/AT)n(6.91%)。沟眶象SSR的平均长度为15.74 bp,长度大于20 bp的SSR仅占总数的12.70%。研究还发现沟眶象微卫星出现的频率和其长度呈极显著负相关(P0.01),相关系数为-0.572。研究结果为开发高多态性微卫星引物来进行沟眶象功能基因组学、种群遗传结构、种群遗传多样性等研究奠定了基础。     

Occurrence and development of Eucryptorrhynchus brandti and E. chinensis (Coleoptera: Curculionidae) on Ailanthus altissima trees subjected to different levels of mechanical damage

Eucryptorrhynchus brandti (Harold) and E. chinensis (Oliver) are herbivores of Ailanthus altissima (Mill.) Swingle (tree of heaven) in China. Eucryptorrhynchus brandti has been recommended as a potential biological control agent of A. altissima in North America. In China, the majority of adults of both species were found on tree trunks 0–5 m above the ground, from May to September. In October and November, most adults were found at the base of A. altissima trees. Trees were subjected to different levels of mechanical injury: very low mechanical injury, one to two 0.015 m² bark sections were removed; low, two to four bark sections were removed; moderate, 8 to 22 bark sections removed; high, tree was girdled; and extreme, tree was felled and the remaining stump was sampled. Very low and low mechanical injury trees had very few adult emergence holes with few larvae developing beyond the first or second instar after 29 months. The health of these trees remained good. An increase in adult emergence holes occurred in moderately injured trees that appeared as healthy as very low to low mechanically injured trees. This may indicate that only a small increase in tree stress can increase the adult emergence rate and thus hasten a decline in tree health. Moderate, high and extreme mechanically injured trees had significantly more emergence holes/m than very low and low injured trees and late larval stages were present. The development of Eucryptorrhynchus species was more successful the greater the degree of mechanical injury. Based on this study both Eucryptorrhynchus species appear to be secondary pests of A. altissima in China.     

Assessing potential biological control of the invasive plant, tree-of-heaven, Ailanthus altissima

Tree-of-heaven, Ailanthus altissima, is a deciduous tree indigenous to China and introduced into North America and Europe. It is a serious threat to ecosystems in introduced areas, as the plant is very competitive, and also contains allelopathic chemicals that may inhibit growth of surrounding native plants. In addition, the plant contains secondary chemicals that make it unpalatable to some insects. In this paper we assess potential biological control of this plant by reviewing literature associated with natural enemies of the plant from both its native and introduced regions in the world. Our literature surveys revealed that 46 phytophagous arthropods, 16 fungi, and one potyvirus were reported attacking tree-of-heaven, some apparently causing significant damage in China. Two weevils, Eucryptorrhynchus brandti and E. chinensis, are major pests of the plant in China and are reportedly restricted to tree-of-heaven, showing promise as potential biological control agents. Nymphs and adults of a homopteran insect, Lycorma delicatula and larvae of two lepidopteran species, Samia cynthia and Eligma narcissus, may also cause severe damage, but they are not host specific. Two rust fungi, Aecidium ailanthi J. Y. Zhuan sp. nov. and Coleosporium sp. have been reported on tree-of-heaven in China and are also promising potential candidates for biological control of the plant. Nine insect herbivores and 68 fungi are associated with tree-of-heaven in its introduced range in North America, Europe, and Asia. An oligophagous insect native to North America, the ailanthus webworm, Atteva punctella, may be a potential biocontrol agent for the plant. Among the fungal species, Fusarium osysporum f. sp. perniciosum, caused wilt of tree-of-heaven in North America and may have the potential to control the plant, but its non-target effect should be carefully evaluated. Our review indicates that there is potential for using insects or pathogens to control tree-of-heaven.     

中华食蜂郭公虫的生物学特性和行为观察

中华食蜂郭公虫Trichodes sinae Chevrolat是西鄂尔多斯地区重要传粉昆虫火红拟孔蜂Hoplitis pyrrhosoma Wu的寄生性天敌。文章报道中华食蜂郭公虫除成虫外各虫态的形态特征、生活史及幼虫和成虫的行为等生物学特性。该虫在西鄂尔多斯地区1年发生1代,越冬幼虫于4月上旬开始化蛹,5月中旬陆续羽化出巢,成虫取食植物补充营养后,开始交尾、产卵。1龄幼虫能够寻找并钻入火红拟孔蜂的巢室,取食火红拟孔蜂幼虫,直至结茧化蛹。室温条件下,卵期约6~8d,幼虫期约260~280d,蛹期约40~50d;雄虫寿命约28~30d,雌虫寿命约35~40d。     

谢氏宽漠王的生物学特性及行为

谢氏宽漠王Mantichorulasemenowi是荒漠半荒漠地区的有害昆虫之一。该文主要探讨了该虫的生物学特性和部分行为。该虫 2年发生 1代 ,世代不整齐 ,以成、幼虫越冬。卵期 1 0～ 1 8d ,幼虫共有 7龄 ,化蛹时间为 6月下旬至 8月上旬 ,蛹经过 1 1～ 1 7d羽化为成虫。食性杂。喜光 ,活动有明显的节律性。     

葱斑潜蝇生物学特性研究

葱斑潜蝇在山东1年发生6－7代,以蛹于10月在地表5cm左右土中越冬。4月下旬越冬代蛹开始羽化,羽化高峰在5－6月,4月下旬始幼虫,5月中旬出现第1代成虫,世代重叠发生,盛发期在6－9月,完成1代需17－31天,其中卵期2－5天,幼虫期3－9天,蛹期11－18天,成虫活动高度多在1m以下,取食,产卵喜在大葱心部第2,3叶,平均单雌产率109．3粒。幼虫潜食主植物的叶片而形成潜道。温度20－32℃、湿度60％－90％利于其生长发育,危害和繁殖。恒温下测得全世代的的发育起点温度为10．0℃,有效积温为361．1日度,土壤含水量5％－15％适宜蛹羽化。寄生性天敌有幼虫幼虫期寄生的姬小蜂6种,寄生率达40％;幼虫一蛹期寄生的金小蜂1种、茧蜂2种,寄生率为28．4％－79．4％。     

葱斑潜蝇的生物学特性

葱斑潜蝇 1年发生 4～ 5代 ,世代重叠严重。以蛹在土中越冬 ,翌年 5月初越冬蛹羽化 ,5月上旬越冬代成虫开始产卵。室内自然变温饲养 ,得到全世代的发育起始温度为 10 .34℃ ,有效积温为 2 57.2 5日度。该虫主要以幼虫潜食叶肉造成危害。周年发生 ,呈春、秋季两个高峰 ,以春季为重。田间天敌主要是潜蝇姬小蜂 Diglyphus sp.、稀网姬小蜂 Euplectrus sp.以及金小蜂科 Pteromalidae中的一种寄生蜂 ,均为幼虫寄生。