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1.
双斑长跗萤叶甲在玉米田的种群消长规律   总被引:1,自引:0,他引:1  
【目的】明确双斑长跗萤叶甲Monolepta hieroglyphica(Motschulsky)的发生规律,为双斑长跗萤叶甲的预测预报和综合治理提供科学依据。【方法】2011年通过田间系统调查对山西省忻州市和晋中市玉米田的双斑长跗萤叶甲的种群消长动态进行了系统研究。【结果】在山西省忻州市的玉米田,越冬卵在5月下旬开始孵化,幼虫以玉米根系为食,6月中旬为幼虫的发生高峰期,部分老熟幼虫开始化蛹,6月下旬成虫开始羽化出土,为害玉米叶片,8月初成虫种群数量达到最高峰,8月中旬以后随着玉米花丝大部分萎蔫,叶片开始衰老,玉米田间的成虫种群数量也急剧下降。10月中旬玉米田成虫基本消失,但是在杂草上还能发现少量的成虫。在山西省晋中市,玉米的生育期比忻州市晚10 d左右,双斑长跗萤叶甲的发生期也相对晚一些,但是种群数量的发生发展趋势基本是一样的。双斑长跗萤叶甲成虫在靠近杂草的玉米田边比在玉米田中部的发生更重,而在成虫的发生高峰期,田边和田中间的种群密度无显著性差异。【结论】双斑长跗萤叶甲在山西省1年发生1代,在山西省忻州市的发生期比晋中市的要早10 d左右,这与两地玉米田的不同的土壤性质、灌溉方式、玉米生育期等因素有关。  相似文献   

2.
蠋敌对双斑长跗萤叶甲成虫的捕食功能研究   总被引:1,自引:0,他引:1  
在室内研究了捕食性天敌蠋敌对双斑长跗萤叶甲成虫的捕食功能反应.结果表明,蠋敌对双斑长跗萤叶甲成虫的捕食功能符合HollingⅡ模型,日最大捕食量为20.4头双斑长跗萤叶甲成虫,捕食一头双斑长跗萤叶甲成虫需要2.94min,功能系数为0.5169;蠋敌成虫个体间相互干扰对捕食效应的影响可以用E=0.4046*P-0.3914模拟;蠋敌若虫对自身密度的功能反应可以用A=0.3034p-0.5357模拟.经卡方检验,其理论值与实测值无统计学差异.  相似文献   

3.
温度对双斑长跗萤叶甲成虫寿命及繁殖的影响   总被引:4,自引:1,他引:3  
双斑长跗萤叶甲Monolepta hieroglyphica(Motschulsky)已成为新疆北疆棉区的一重大新害虫,在室内5个恒温下(19、22、25、28和31℃)研究了温度对双斑长跗萤叶甲成虫寿命及生殖力的影响。结果表明,在19、22、25、28和31℃下雌雄成虫平均寿命分别为64.1、60.8、55.6、42.1和34.7d,雌虫平均寿命明显长于雄虫;温度对雌成虫产卵前期、产卵期及产卵量有影响,在前述19~31℃5个温度下,其平均产卵量分别为29.2、82.1、93.8、73.4和63.1粒/雌。  相似文献   

4.
双斑长跗萤叶甲的发育起点温度与有效积温   总被引:1,自引:1,他引:0  
双斑长跗萤叶甲Monolepta hieroglyphica(Motschulsky)已成为新疆北疆棉区的一重大新害虫,至今该虫各虫态的发育历期都不清楚。在室内5个恒温下(19,22,25,28和31℃),利用有效积温法则和"最小二乘法"对双斑长跗萤叶甲各虫态的发育起点温度和有效积温进行研究。结果表明,卵期、幼虫期、蛹期和产卵前期的发育起点温度分别为9.8,10.8,12.6和10.1℃;有效积温分别为1 182.2,401.2,111.9和269.0日.度;整个世代完成发育所需要的有效积温为1 971.6日.度,预测在新疆北疆1年发生1代。  相似文献   

5.
双斑长跗萤叶甲是新疆北疆棉花的主要害虫之一。本研究旨在探索短时高温对双斑长跗萤叶甲成虫生理生化的影响。在室内研究了不同高温(33℃、37℃、41℃、45℃)不同时间(0.5 h、1.5 h、2.5 h、6 h、12 h)处理后,双斑长跗萤叶甲成虫体内总蛋白含量、过氧化物酶(POD)及过氧氢酶(CAT)的变化规律。双斑长跗萤叶甲成虫总蛋白在37℃处理12 h时,蛋白含量最高,41℃处理12 h时有所下降,45℃时双斑长跗萤叶甲只能存活1.5 h,但蛋白含量仍高于对照(26℃)。POD活性随温度升高先升高后降低。在33℃处理6 h时,活性最高,在41℃处理12 h时,活性最低。CAT活性在同一时间不同温度处理中呈先降后升再降趋势。在37℃处理1.5 h时活性达到最高,在41℃处理12 h时活性最低。在同一温度不同处理时间中,CAT活性在33℃时先升高后降低,在37℃、41℃时随时间的延长先升高后降低,在45℃时持续降低,且显著低于对照(26℃)。双斑长跗萤叶甲总蛋白及保护酶的活性与温度密切相关,据此推测高温下双斑长跗萤叶甲成虫死亡的原因与保护酶系统被破坏有关。  相似文献   

6.
[目的]明确齐齐哈尔市玉米田双斑长跗萤叶甲Monolepta hieroglyphica成虫发生规律,为该害虫的预测预报和综合防治提供科学依据.[方法]2017-2019年,通过在齐齐哈尔市玉米田间罩网,定点观察双斑长跗萤叶甲成虫羽化动态、虫体大小、发生数量与温度及降雨量的关系.[结果]成虫羽化出土始见期在7月上中旬,初期羽化出土的成虫虫体偏小;7月下旬-8月上旬为成虫羽化出土高峰期,虫体的长度与宽度明显增大,8月上中旬,羽化出土的成虫虫体达到最大值;8月中旬以后羽化出土成虫数量明显下降,成虫虫体的长度与宽度逐渐减小;到8月下旬-9月上旬只有少量的成虫羽化出土,成虫虫体的大小与初期羽化出土期的相近;9月中旬以后零星羽化出土的成虫虫体大小达到最小值;9月下旬以后未见有成虫羽化出土,10月上旬田间成虫消失.双斑长跗萤叶甲成虫羽化出土持续时间在61-74 d,平均1 m2玉米田羽化出土的成虫12.0-97.8头.温度对双斑长跗萤叶甲成虫羽化出土始见期、盛发期、持续时间影响较大,5-7月温度高有利于成虫羽化出土.降雨量对羽化出土的双斑长跗萤叶甲成虫总量影响较大,6-8月降雨量大羽化出土的成虫数量减少.[结论]齐齐哈尔玉米田双斑长跗萤叶甲成虫在7月上中旬羽化出土,8月上中旬达到高峰,与当地玉米抽雄吐丝期相遇,8月中旬后成虫羽化数量明显减少,8月下至9月初仅有零星羽化出土,9月下旬无新羽化出土,10月上旬田间成虫消失.成虫虫体大小与羽化时期密切相关,以羽化盛期的虫体最大.温度和降水影响成虫的羽化时间和数量.  相似文献   

7.
利用扫描电镜观察了双斑长跗萤叶甲Monolepta hieroglyphica (Motschulsky)成虫触角及其感器的形态与分布.结果表明:双斑长跗萤叶甲成虫触角为线状,由柄节、梗节和鞭节组成,鞭节有9节,其中,雄虫的触角比雌虫长;感器类型有毛形感器(1型、2型和3型)、刺形感器、锥形感器(1型和2型)、腔锥形感器、B(o)hm氏鬃毛、钟形感器共9种.雌雄成虫触角感器类型无差异,但雄虫触角上的感器分布要比雌虫的稠密.  相似文献   

8.
孟玲  徐军 《昆虫知识》2007,44(5):711-715
豚草条纹萤叶甲Ophraella communa LeSage是恶性入侵豚草(Ambrosia artemisiifolia L.)的天敌,用频次分布拟合和多种聚集指数测度等方法对该叶甲的成虫、幼虫和蛹、卵的空间分布型进行研究。结果表明,豚草条纹萤叶甲卵、幼虫+蛹、成虫的空间分布符合负二项分布,种群个体的空间分布为聚集分布。用几种衡量聚集度的指标,对上述各虫态分布的聚集程度进行测定;然后计算出各虫态田间最适理论抽样数。  相似文献   

9.
利用扫描电镜观察了双斑长跗萤叶甲Monolepta hieroglyphica(Motschulsky)成虫触角及其感器的形态与分布。结果表明:双斑长跗萤叶甲成虫触角为线状,由柄节、梗节和鞭节组成,鞭节有9节,其中,雄虫的触角比雌虫长;感器类型有毛形感器(1型、2型和3型)、刺形感器、锥形感器(1型和2型)、腔锥形感器、Bhm氏鬃毛、钟形感器共9种。雌雄成虫触角感器类型无差异,但雄虫触角上的感器分布要比雌虫的稠密。  相似文献   

10.
封面照片     
正照片示双斑长跗萤叶甲Monolepta hieroglyphica (鞘翅目:叶甲科)成虫在玉米Zea mays (禾本科)花丝上群聚取食。双斑长跗萤叶甲主要以成虫在玉米叶片、花丝及幼嫩籽粒,特别是取食咬断玉米花丝,甚至把花丝咬食光,导致玉米不能正常授粉灌浆或授粉推迟,影响结实和灌浆,咬食子粒诱发玉米穗腐病的发生,严重影响玉米的产量和品质。本期报道了中国南方双斑长跗萤叶甲地理种群遗传结构及Wolbachia感染研究(pp. 730-742)。本照片由王振营于2012年9月摄于黑龙江291农场。  相似文献   

11.
Between 1974 and 1978, 2,842 identifications of plant-parasitic nematodes were made from more than 1,700 soil and plant samples collected in eight provinces of South Viet Nam. Species in nine genera—Helicotylenchus, Criconemoides, Meloidogyne, Pratylenchus, Tylenchorhynchus, Hoplolaimus, Hirschmanniella, Xiphinema, and Rotylenchulus—comprised 96.1% of the identifications; the remaining 3.9% were species of 11 genera. Fourteen genera were associated with rice which was grown on about 2,500,000 ha in 1970. Of these, Ditylenchus, Hirschmanniella, and Meloidogyne were most important. Ditylenchus angustus caused severe damage to about 50,000 ha of flooded rice in the Mekong Delta in 1976. Hirschmanniella spp. were found in all samples examined from flooded rice fields. Meloidogyne spp. were common in rice seedbeds, upland rice, and rice not kept flooded continuously. Meloidogyne and Pratylenchus spp. were found in roots of 22 of the 32 crop plants sampled. Little or no attempt was made in South Viet Nam to control nematodes.  相似文献   

12.
Parasitic nematodes from the Berlin (ZMB) and Vienna (NMW) Museum collections referred to the genus Filaria Mueller, 1787 by von Linstow or Molin were studied. Three samples were in good condition and the specimens redescribed. Litomosa hepatica (von Linstow, 1897) n. comb., sample ZMB Vermes Entozoa 3368, from the megachiropteran Pteropus neohibernicus, Bismarck Archipelago, resembles L. maki Tibayrenc, Bain & Ramanchandran, 1979, from Pteropus vampyrus, in Malaysia, but the buccal capsule differs. Both species display particular morphological characters which differ from species of Litomosa parasitic in microchiropterans. The remaining material originates from Brazil. The spicule morphology of Litomosoides circularis (von Linstow, 1899) Chandler, 1931, sample ZMB Vermes Entozoa 1059 from Hesperomys spec. (= Holochilus brasiliensis), Porto Alegre, confirms that it belongs to the sigmodontis group; the microfilaria presents characters of the genus Litomosoides, e.g. body attenuated at both extremities and salient cephalic hook. Taxonomic discussions by others confirm that species of Litomosoides belonging to the sigmodontis group and described subsequently are distinct from L. circularis. Litomosoides serpicula (Molin, 1858) Guerrero, Martin, Gardner & Bain, 2002, is redescribed, sample NMW 6323 from the bat Phyllostoma spiculatum (= Sturnira lilium), Ypanema. It is very close to L. brasiliensis Almeida, 1936, type host Moytis sp., but distinguished by a single ring in the buccal capsule, rather than two, supporting previous conclusions that the taxon L. brasiliensis, as generally regarded, may represent a complex of species. Samples NMW 6322 and NMW 6324, from other bats and also identified by Molin (1858) as Filaria serpicula, contain unidentifiable fragments of Litomosoides incertae sedis. Filaria hyalina von Linstow, 1890, sample ZMB Vermes Entozoa Q 3905 from Sorer vulgaris (= Sorex araneus), is incertae sedis because it contains two unidentifiable posterior parts of male, which might be an acuarid, Stammerinema sp. Filaria vesperuginis von Linstow, 1885, sample ZMB Vermes Entozoa Q 3929, from the bat Vesperugo serotinus (= Eptesicus serotinus), contains encysted nematode larvae and is a nomen dubium.  相似文献   

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14.
A broad multilocus phylogenetic analysis (MLPA) of the representative diversity of a genus offers the opportunity to incorporate concatenated inter-species phylogenies into bacterial systematics. Recent analyses based on single housekeeping genes have provided coherent phylogenies of Aeromonas. However, to date, a multi-gene phylogenetic analysis has never been tackled. In the present study, the intra- and inter-species phylogenetic relationships of 115 strains representing all Aeromonas species described to date were investigated by MLPA. The study included the independent analysis of seven single gene fragments (gyrB, rpoD, recA, dnaJ, gyrA, dnaX, and atpD), and the tree resulting from the concatenated 4705 bp sequence. The phylogenies obtained were consistent with each other, and clustering agreed with the Aeromonas taxonomy recognized to date. The highest clustering robustness was found for the concatenated tree (i.e. all Aeromonas species split into 100% bootstrap clusters). Both possible chronometric distortions and poor resolution encountered when using single-gene analysis were buffered in the concatenated MLPA tree. However, reliable phylogenetic species delineation required an MLPA including several “bona fide” strains representing all described species.  相似文献   

15.
Microbial transformation of zaluzanin-D   总被引:2,自引:0,他引:2  
Microbial transformation of zaluzanin-D using different fungi gave 11,13-dihydrozaluzanin-C, zaluzanin-C, 4,16,11,13 - tetrahydro zaluzanin-C, estafiatone, dihydroestafiatol and dihydroestafiatone.  相似文献   

16.
The late-third-instar labial disc is comprised of two disc-proper cell layers, one representing mainly the ventral half of the anterior compartment (L-layer) and the other, the dorsal half of the anterior compartment and most, if not all, of the posterior compartment (M-layer). In the L-layer, Distal-less represses homothorax whereas no Distal-less-dependent homothorax repression occurs in the M-layer where Distal-less is coexpressed with homothorax. In wild-type labial discs, clawless, one of the two homeobox genes expressed in distal cells receiving maximum (Decapentaplegic+Wingless) signaling activity in leg and antennal discs, is specifically repressed by proboscipedia. A fate map, inferred from data on basic patterning gene expression in larval and pupal stages and mutant phenotypes, indicates the inner surface of the labial palpus, which includes the pseudotracheal region, to be a derivative of the distal portion of the M-layer expressing wingless, patched, Distal-less and homothorax. The outer surface of the labial palpus with more than 30 taste bristles derives from an L-layer area consisting of dorsal portions of the anterior and posterior compartments, each expressing Distal-less. Our analysis also indicates that, in adults and pupae, the anterior-posterior boundary, dividing roughly equally the outer surface of the distiproboscis, runs along the outer circumference of the inner surface of distiproboscis.  相似文献   

17.
The present generic concept of Phoma is broadly defined, with nine sections being recognised based on morphological characters. Teleomorph states of Phoma have been described in the genera Didymella, Leptosphaeria, Pleospora and Mycosphaerella, indicating that Phoma anamorphs represent a polyphyletic group. In an attempt to delineate generic boundaries, representative strains of the various Phoma sections and allied coelomycetous genera were included for study. Sequence data of the 18S nrDNA (SSU) and the 28S nrDNA (LSU) regions of 18 Phoma strains included were compared with those of representative strains of 39 allied anamorph genera, including Ascochyta, Coniothyrium, Deuterophoma, Microsphaeropsis, Pleurophoma, Pyrenochaeta, and 11 teleomorph genera. The type species of the Phoma sections Phoma, Phyllostictoides, Sclerophomella, Macrospora and Peyronellaea grouped in a subclade in the Pleosporales with the type species of Ascochyta and Microsphaeropsis. The new family Didymellaceae is proposed to accommodate these Phoma sections and related anamorph genera. The present study demonstrated that Phoma radicina, the type species of Phoma sect. Paraphoma and Phoma heteromorphospora, the type species of Phoma sect. Heterospora can be assigned to the Phaeosphaeriaceae and Leptosphaeriaceae respectively.  相似文献   

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20.
Antennapedia is one of the homeotic selector genes required for specification of segment identity in Drosophila. Dominant mutations that ectopically express Antennapedia cause transformation of antenna to leg. Loss-of-function mutations cause partial transformation of leg to antenna. Here we examine the role of Antennapedia in the establishment of leg identity in light of recent advances in our understanding of antennal development. In Antennapedia mutant clones in the leg disc, Homothorax and Distal-less are coexpressed and act via spineless to transform proximal femur to antenna. Antennapedia is negatively regulated during leg development by Distal-less, spineless, and dachshund and this reduced Antennapedia expression is needed for the proper development of distal leg elements. These findings suggest that the temporal and spatial regulation of the homeotic selector gene Antennapedia in the leg disc is necessary for normal leg development in Drosophila.  相似文献   

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