柑橘大实蝇羽化出土及橘园成虫诱集动态研究

【背景】柑橘大实蝇是柑橘类果树上的重要害虫。预测该虫的羽化出土进度、掌握成虫发生动态是指导橘同成虫期防治的重要依据。【方法】本研究通过在25℃恒温、室内常温和室外网室3种条件下饲养柑橘大实蝇的蛹,以逐日观察成虫羽化出土数量;在重庆武隆、四川江油等5个地区共设置240个麦克菲尔（MePhail）诱集器,以糖酒醋液和水解蛋白为诱饵诱集成虫,得到柑橘大实蝇成虫羽化出土的逐日数量和橘园成虫诱集的逐期数量。【结果】用逻辑斯带模型拟合成虫羽化出土和橘园成虫诱集动态,结果表明,成虫的始盛期、高峰期和盛末期在25℃恒温条件下分别为4月25日、28日和30日,盛期的持续时间为6d;在室内常温条件下分别为5月3日、7日和10日,盛期的持续时间为8d;在室外网室条件下分别为5月8日、14日和18日,盛期的持续时间为11d;橘园诱集成虫分别为6月2日、14日和26日,盛期的持续时间为25d。【结论与意义】随着羽化期温度的提高,柑橘大实蝇羽化出土期提前,历期缩短,羽化整齐。虽然网室成虫羽化和橘园成虫诱集都处于室外条件,但后者的始盛期、盛期和盛末期比前者分别迟了36、30和22d。因此,建议采用室外网室饲养蛹的方法监测柑橘大实蝇成虫的发生期,若仅凭橘园诱集成虫的数据,因其滞后性十分明显,对指导柑橘大实蝇成虫防治的意义不大。     

三峡河谷地区柑橘大实蝇羽化、交配及产卵习性

对柑橘大实蝇Bactrocera(Tetracus) minax(Enderlein)的羽化、交配与产卵习性进行初步观察。结果表明,柑橘大实蝇的出土始期为每年的5月8日~5月14日,高峰为5月12日~5月18日,末期为5月30日~6月4日,近几年出土时间有所提前。在早熟蜜柑上主要产卵于果腰部,深度约为4.5mm;在中晚熟蜜柑上主要产卵于果蒂部,深度约为4.1mm;在脐橙上主要产卵于果脐部,深度约为9.7mm;在柚上主要产卵于果蒂和果腰部,深度约为13.0mm。观察结果也与以往记载有所不同。     

柑橘大实蝇觅食高峰期成虫量与产卵痕率的关系模型研究

【目的】通过研究柑橘大实蝇Bactrocera minax觅食高峰期成虫发生量与产卵痕率的关系,为柑橘大实蝇的预测预报和综合防治提供理论指导。【方法】通过调查柑橘大实蝇觅食高峰期在全田、橘园、杂树林、橘园与杂树林交界带和橘园中心的诱虫量和产卵痕率,建立二者在不同观测区域上的回归方程,为根据柑橘大实蝇觅食高峰期成虫发生量来预测产卵痕率,进而根据产卵痕率确定成虫期防治指标提供理论基础。【结果】除了果园周边杂树林中柑橘大实蝇觅食高峰期成虫诱捕量的线性回归与非线性回归的分析均不理想,不适宜用于产卵痕率的预测外,其他观测区域柑橘大实蝇觅食高峰期成虫诱捕量与果实产卵痕率建立的线性回归与非线性回归方程的拟合效果好,可以作为产卵痕率的预测模型。但不同区域的拟合效果存在差异,其中橘园中心成虫量与产卵痕率回归方程拟合效果(R~2=0.957 5,RMSE=1.623)最好,其他依次分别是:整个橘园成虫量(R~2=0.945 4, RMSE=1.859),全田成虫量(R~2=0.898 2,RMSE=2.535),交界带成虫量(R~2=0.851 5,RSME=3.038)。【结论】这些回归方程均能够较好的预测产卵痕率。考虑到防治需要,可以在橘园中心设置诱捕点,以觅食高峰期的成虫量(x)预测产卵痕率(y),y=0.031 3x~3-1.306 5x~2+17.206 0x-17.036,达到为柑橘大实蝇预测预报和综合防治提供理论指导的目的。     

河北省草本植物物候特征及其对气候变暖的响应

以1981—2006年河北省8个国家农业气象观测站的草本植物物候观测资料和47个气象站的地面观测资料为基础,运用EOF和REOF等统计学方法,研究了河北省草本植物物候期的变化特征及其对气候变暖的响应。结果表明:河北省草本植物展叶始期总体呈提前趋势,其中东部沿海平原提前趋势最大,中南部平原次之,西北部山区最小;黄枯始期主要表现出推迟趋势,生长季长度以延长趋势为主;春季气温对展叶始期的影响显著,河北省春季气温上升1℃,草本植物展叶始期提前4.1d;各站点生长季倾向率与年均温倾向率呈正相关,即年均温升幅大的站点,生长季延长的幅度也较大;草本植物物候变化特征及其对气候变暖的响应与木本植物基本一致,研究结果对丰富河北省物候与气候变化关系研究具有一定意义。     

短时温和低温对柑橘大实蝇1～4级蛹羽化的影响

柑橘大实蝇Bactrocera minax(Enderlein)是我国柑橘类的重要害虫。与恒定的相对高温相比,冬季自然低温长期作用利于柑橘大实蝇蛹的存活。但短时的温和低温(发育起点以上,25℃室温以下)对柑橘大实蝇1~4级蛹存活的影响尚不明确。[目的]本研究旨在探索不同时长的短时温和低温对柑橘大实蝇1-4级蛹存活的影响。[方法]利用短时温和低温暴露处理柑橘大实蝇不同级别(1,2~3,4级)蛹,考察其在10、15、20℃下暴露2、4、8h后的成虫羽化率。采用双因素方差分析法分析温度和时长对柑橘大实蝇蛹存活的影响,利用LSD法比较温度或时长的单独作用效果。[结果]温度和时长对柑橘大实蝇1级蛹和4级蛹无交互作用,对2~3级蛹有极显著交互作用。柑橘大实蝇1级蛹短时暴露于15°℃和20℃下的成虫羽化率(66.79%,59.93%),2~3级蛹在10°℃和15°℃下暴露4h和8h的成虫羽化率(10°℃:50.59%,58.80%;15℃:54.96%,55.61%),4级蛹短时暴露于10、15、20℃下的成虫羽化率(52.10%,53.30%,51.62%),与CK的成虫羽化率(25℃恒温下42.81%)相比,均显著提高。[结论]特定短时低温利于柑橘大实蝇蛹的存活,柑橘大实蝇不同级别的蛹对短时温和低温的敏感性不同,结果可为柑橘大实蝇蛹的保存、成虫发生动态的精准预测提供依据。     

白星花金龟室内外繁育技术研究

[目的]根据新疆气候特点和白星花金龟Protaetia brevitarsis Lewis生物学特性,探究在新疆人工繁育白星花金龟的可行性及潜力,以期为白星花金龟在新疆的人工繁殖和转化利用畜禽粪便提供科学依据.[方法]以牛粪为繁育基质,在适宜季节分别在室内外保育白星花金龟的蛹及作为成虫产卵基质,最终统计比较室内外成虫的羽化及产卵情况.[结果]室外露天条件更利于白星花金龟的羽化,老熟幼虫做土室26 d后羽化出成虫,比室内及室外棚下处理提前4d.在化蛹30d后进入羽化高峰期,持续13d,羽化率83％.成虫雌雄比接近1∶1,雌虫羽化时间早于雄虫1-3 d.白星花金龟成虫室内外产卵量差异不显著(P＜0.05),室内单雌产卵量109.80粒,室外105.94粒,成虫羽化后30-35 d进入产卵高峰期,第60天室内外成虫产卵量显著下降(P＜0.05),甚至不产卵.[结论]白星花金龟规模化人工繁育在新疆是可行性的,在室外自然条件和室内控温条件下白星花金龟繁育的效果差异不显著.     

沈阳城市森林主要树种物候对气候变暖的响应

采用统计和线性回归方法,探讨了近40年来沈阳城市森林主要树种物候对气候变暖的响应.结果表明,沈阳城市森林树木休眠期长短与冬季气温密切相关,适宜的寒冷条件有利于解除树木休眠期;树木萌动期早晚与冬季和早春气温高低呈显著的负相关关系,冬春季气温越高,芽萌动越提前.树木爆芽后15 d左右开始展叶,展叶早晚主要受展叶前的春季气温高低的影响,但与冬季气温没有相关关系.始花前2～8旬,特别是2～4旬气温对始花期影响最显著,春季气温升高始花期提前. 树木芽萌动期、展叶始期与寒冷指数（CI）呈显著正相关关系,而开花始期与CI没有相关关系.沈阳城市森林树木对气候变暖的响应,主要表现在年均温升高1 ℃,芽萌动期提前9 d,展叶始期提前10 d,开花始期提前5 d.     

重庆地区柑桔大实蝇系统监测研究

柑桔大实蝇Bactrocera minax是柑桔类植物果实的重要害虫,以往对该虫的发生监测仅局限于通过果园诱集和室内外养蛹监测成虫的发生期。本研究综合应用室外养蛹、桔园系统调查、成虫诱集和蛆果解剖等技术手段,以期了解柑桔大实蝇的产卵进度、幼虫发育进度、蛆果落地进度、幼虫化蛹进度以及蛹的羽化进度。研究结果表明,重庆地区柑桔大实蝇产卵盛期为6月下旬-7月上旬,高峰期为6月下旬末-7月初;一龄、二龄和三龄幼虫的发生盛期分别为9月中旬-10月初、10月上旬-下旬和10月中旬-11月初;受害蛆果落地盛期为10月上旬-下旬,与二龄和三龄幼虫的发生盛期吻合;室外养蛹的成虫羽化盛期为5月上旬-中旬末,但果园成虫诱集的盛期为6月中旬-下旬,较室外养蛹的成虫发生盛期推迟30 d左右,对出现此种情况的原因作者做了初步分析。研究结果还表明,各虫态的累计发生进度均可用逻辑斯缔方程拟合,从而可计算出各虫态发生进度为16%、50%和84%的始盛期、高峰期和盛末期。研究结果对于柑桔大实蝇的发生期预测和防治具有重要指导意义。     

半闭弯尾姬蜂羽化、交配及产卵行为观察

在22℃,相对度60％～70％的实验室条件下,研究了半闭弯尾姬蜂Diadegma semiclausum的羽化、交配与产卵行为。结果表明：半闭弯尾姬蜂蜂蛹从开始羽化到羽化结束历经4d,羽化高峰期出现在羽化的第3d,羽化数量为25头,占全部羽化数量的58．82％;第3d中羽化高峰出现在8：00～13：00,羽化数量为16．5头,占全天羽化数量的66．00％。半闭弯尾姬蜂交配过程大致分为3个阶段：准备阶段、交配阶段、结束阶段;交配后开始产卵,产卵过程大致分为寄主寻找和确定、穿刺和产卵、产卵结束和梳理。     

柑橘大实蝇的产卵特性

通过田间调查,明确柑橘大实蝇Bactrocera (Tetradacus) minax (Enderlein)的产卵特性和在3种寄主植物上产卵的时间动态。柑橘大实蝇对杂柑为害率最高,3个寄主品种均以中层北面果实受害严重。柑橘大实蝇最喜在直径为(3.3±0.2)cm的果实上产卵。     

Foreign exploration for Scirtothrips perseae Nakahara (Thysanoptera: Thripidae) and associated natural enemies on avocado (Persea americana Miller)

Scirtothrips perseae Nakahara was discovered attacking avocados in California, USA, in 1996. Host plant surveys in California indicated that S. perseae has a highly restricted host range with larvae being found only on avocados, while adults were collected from 11 different plant species. As part of a management program for this pest, a “classical” biological control program was initiated and foreign exploration was conducted to delineate the home range of S. perseae, to survey for associated natural enemies and inventory other species of phytophagous thrips on avocados grown in Mexico, Guatemala, Costa Rica, the Dominican Republic, Trinidad, and Brazil. Foreign exploration efforts indicate that S. perseae occurs on avocados grown at high altitudes (>1500 m) from Uruapan in Mexico south to areas around Guatemala City in Guatemala. In Costa Rica, S. perseae is replaced by an undescribed congener as the dominant phytophagous thrips on avocados grown at high altitudes (>1300 m). No species of Scirtothrips were found on avocados in the Dominican Republic, Trinidad, or Brazil. In total, 2136 phytophagous thrips were collected and identified, representing over 47 identified species from at least 19 genera. The significance of these species records is discussed. Of collected material 4% were potential thrips biological control agents. Natural enemies were dominated by six genera of predatory thrips (Aeolothrips, Aleurodothrips, Franklinothrips, Leptothrips, Scolothrips, and Karnyothrips). One genus each of parasitoid (Ceranisus) and predatory mite (Balaustium) were found. Based on the results of our sampling techniques, prospects for the importation of thrips natural enemies for use in a “classical” biological control program in California against S. perseae are not promising.     

Taxonomic status of the species of the green algal genusNeochloris

Komárek has recently reviewed the various species assigned to the green algal genusNeochloris Starr (Chlorococcales, Chlorococcaceae) and removed those with uninucleate vegetative cells to a new genus,Ettlia. Watanabe & Floyd, unaware ofKomárek's work, also reviewed the species ofNeochloris and distributed them among three genera—Neochloris, Chlorococcopsis gen. nov., andParietochloris gen. nov.—on the basis of details of the covering of the zoospore and the arrangement of the basal bodies of the flagellar apparatus. This paper reconciles these two treatments and makes additional recommendations at the ranks of genus, family, order, and class.     

Die GattungKarschia — Bindeglied zwischen bitunicaten Ascomyceten und lecanoralen Flechtenpilzen?

The genusKarschia, in the earlier sense, including saprophytes and parasites on lichens, has been thought to be a non-lichenized parallel genus of the lichen genusBuellia. Modern workers included it on the one hand inBuellia, on the other hand combined it with bitunicate ascomycetes. It is now proved thatKarschia is heterogeneous and contains but superficially similar members both of the genusBuellia of theLecanorales and of typical or masked bitunicateAscomycetes. Therefore, it can not be regarded as a link betweenLecanorales andDothideales. The type species ofKarschia belongs to theDothideales.

     

Systematic significance of mature embryo of bamboos

The mature embryo of seven species belonging to five genera of Indian bamboos is described. In all these the basic pattern of embryo organisation is same: the scutellar and coleoptilar bundles are not separated by an internode, the epiblast is absent, the lower portion of the scutellum and the coleorhiza are separated by a cleft and the margins of embryonic leaves overlap. The features unique to fleshy fruited bamboos are: presence of a massive scutellum, the juxtaposition of plumule and radicle and the occurrence of a bud in the axil of the coleoptile. The fleshy fruit bearing bamboos should be classified into one group, the tribeMelocanneae. Evidence is provided to recognise additional groups in the subfamilyBambusoideae.     

Phylogeny of cardinalfishes (Teleostei: Gobiiformes: Apogonidae) and the evolution of visceral bioluminescence

The cardinalfishes (Apogonidae) are a diverse clade of small, mostly reef-dwelling fishes, for which a variety of morphological data have not yielded a consistent phylogeny. We use DNA sequence to hypothesize phylogenetic relationships within Apogonidae and among apogonids and other acanthomorph families, to examine patterns of evolution including the distribution of a visceral bioluminescence system. In conformance with previous studies, Apogonidae is placed in a clade with Pempheridae, Kurtidae, Leiognathidae, and Gobioidei. The apogonid genus Pseudamia is recovered outside the remainder of the family, not as sister to the superficially similar genus Gymnapogon. Species sampled from the Caribbean and Western Atlantic (Phaeoptyx, Astrapogon, and some Apogon species) form a clade, as do the larger-bodied Glossamia and Cheilodipterus. Incidence of visceral bioluminescence is found scattered throughout the phylogeny, independently for each group in which it is present. Examination of the fine structure of the visceral bioluminescence system through histology shows that light organs exhibit a range of morphologies, with some composed of complex masses of tubules (Siphamia, Pempheris, Parapriacanthus) and others lacking tubules but containing chambers formed by folds of the visceral epithelium (Acropoma, Archamia, Jaydia, and Rhabdamia). Light organs in Siphamia, Acropoma, Pempheris and Parapriacanthus are distinct from but connected to the gut; those in Archamia, Jaydia, and Rhabdamia are simply portions of the intestinal tract, and are little differentiated from the surrounding tissues. The presence or absence of symbiotic luminescent bacteria does not correlate with light organ structure; the tubular light organs of Siphamia and chambered tubes of Acropoma house bacteria, those in Pempheridae and the other Apogonidae do not.     

Biological control of three floating water weeds,<Emphasis Type="Italic">Eichhornia crassipes,Pistia stratiotes</Emphasis>, and <Emphasis Type="Italic">Salviniamolesta</Emphasis> in the Republic of Congo

Since 1999, four specific weevils (Coleoptera, Curculionidae) were released in the Republic of Congo against three exotic floating water weeds: Neochetina eichhorniae Warner and N. bruchi Hustache against water hyacinth, Neohydronomus affinis Hustache against water lettuce, and Cyrtobagous salviniae Calder and Sands against water fern. Recoveries of exotic weevils were made from all 24 release sites except one, and all four species have established and spread (up to 800 km for water hyacinth weevils). Within a few years of releases, control of water fern and water lettuce was such that fishing and navigation could be resumed, while reductions of water hyacinth populations were only beginning.     

A molecular phylogeny of Hebeloma species from Europe

In order to widen the scope of existing phylogenies of the ectomycorrhizal agaric genus Hebeloma a total of 53 new rDNA ITS sequences from that genus was generated, augmented by sequences retrieved from GenBank, and analysed using Bayesian, strict consensus and neighbour joining methods. The lignicolous Hebelomina neerlandica, Gymnopilus penetrans, and two species of Galerina served as outgroup taxa. Anamika indica, as well as representatives of the genera Hymenogaster and Naucoria, were included to test the monophyly of Hebeloma, which is confirmed by the results. Hebeloma, Naucoria, Hymenogaster and Anamika indica cluster in a strongly supported monophyletic hebelomatoid clade. All trees largely reflect the current infrageneric classification within Hebeloma, and divide the genus into mostly well-supported monophyletic groups surrounding H. crustuliniforme, H. velutipes, H. sacchariolens, H. sinapizans, and H. radicosum, with H. sarcophyllum being shown at an independent position; however this is not well supported. The section Indusiata divides with strong support into three groups, the position of the pleurocystidiate Hebeloma cistophilum suggests the possible existence of a third subsection within sect. Indusiata. Subsection Sacchariolentia is raised to the rank of section.