广州小斑螟发生与环境因子的关系

广州小斑螟是红树林的一种灾害性的食叶害虫.通过室内饲养和野外观察,对广州小斑螟的发生和环境因素的关系进行了详细的研究.结果表明,随着龄级的增加,取食量增大;在不同样地不同滩位的虫口密度差异性规律不同;在单株白骨壤的不同方位虫口密度差异显著,正南方向虫口密度最高,正西、正北虫口密度最低;在单株白骨壤的中上部明显高于下部;广州小斑螟大龄幼虫较耐水淹,水淹6h的死亡率为0;不同地区温度的差异可导致广州小斑螟的发育进度的不同.     

灭幼脲Ⅲ号、苏云金杆菌防治广州小斑螟药效试验

广州小斑螟Oligochroa cantonella(Caradja)是红树林的主要害虫,主要为害白骨壤Avicennia marina,在深圳市福田红树林保护区每年发生2～3代,其幼虫附着于叶片背面,取食下表皮和叶肉,留下薄薄的上表皮,给防治带来困难.     

硅对镉胁迫下红树白骨壤酚类代谢的影响

采用水培方式研究硅对重金属镉胁迫下白骨壤幼苗酚类代谢影响,探讨硅对白骨壤耐受重金属胁迫的影响,结果表明,低浓度镉胁迫(Cd 0.5 mg·L-1)下,随着外源硅的增加,叶片和根系丙二醛含量降低,但Si 50 mg·L-1处理中各器官总酚含量最高,硅对各器官单宁含量影响不显著;高浓度镉(Cd 5 mg·L-1)导致白骨壤叶片和根系膜脂过氧化,使得丙二醛含量显著高于对照,外源硅的添加显著降低了白骨壤叶片和根系丙二醛积累,Si 100mg·L-1显著增加了各器官中总酚含量和单宁含量,根系丙二醛含量与根系总酚含量呈显著负相关,叶片丙二醛含量与叶片单宁含量呈显著负相关,表明硅显著刺激高镉胁迫下白骨壤植物组织中酚类物质代谢,增加根系和叶片的抗氧化性,进而增加白骨壤对镉的耐受性。     

小叶女贞新害虫黄环绢须野螟生物学特性

黄环绢须野螟Palpitaannulata(Fabricius)是小叶女贞(LigustrumquihouiCarr.)上新出现的一种害虫,严重危害小叶女贞叶片,造成植株枯萎、死亡,同时也危害金叶女贞(L.vicaryi)。该虫在湖南省衡阳地区1年发生3代,以蛹在土中越冬。越冬代成虫和第1、2代成虫分别于4月下旬、5月下旬和6月下旬出现。成虫产卵于嫩梢顶端叶片上,卵期3d,幼虫期9～12d。5月上旬和6月上旬分别是第1代和第2代幼虫盛发期,危害最重。越冬代成虫羽化期喷药是防治该虫的关键,在成虫期和幼虫期分别用40%氧化乐果乳油、50%辛硫磷乳油1000～1200倍或25%溴氰菊酯乳油2500～3000倍稀释液喷洒寄主叶面,可控制该虫危害。     

香樟害虫——橄绿瘤丛螟的生物学特性

研究发现嘉兴地区危害香樟树的丛螟科害虫为橄绿瘤丛螟Orthaga olivacea(Warren),对该虫的生物学特性和发生规律做了研究。该虫较为喜欢危害5~10年生香樟树,多头幼虫聚集在一起取食叶片,并缀合受害叶片成鸟巢状虫苞。在嘉兴地区1年发生2代。根据计算幼虫可分为7龄,符合Dyer生长规律。     

松果梢斑螟对虫害诱导寄主防御的抑制作用

以松果梢斑螟（Dioryctria pryeri）-油松（Pinus tabuleaformis）（2年生球果和新梢）为研究对象,探讨梢斑螟幼虫对油松球果小卷蛾（Gravitarmata margarotana）先期虫害诱导寄主防御的抑制作用,以及虫害诱导的负防御机制。结果表明,双萜松脂酸作为油松球果和新梢的主要组成和诱导性防御物质,梢斑螟虫害后球果双萜松脂酸极显著增加,10 d后降低到正常水平;而新梢虫害后,松脂酸显著增加,后随新梢基础含量而增加,10 d后虫害新梢松脂酸显著高于球果。梢斑螟幼虫以小卷蛾虫害球果、健康球果和新梢等部位为食料,均为梢斑螟5龄幼虫下唇腺葡萄糖氧化酶（Glucose oxidase,GOX）活性最高,极显著高于4龄和3龄幼虫;且同一龄期,小卷蛾虫害球果中的梢斑螟幼虫GOX活性最高,显著高于新梢和健康球果中幼虫酶活性。研究发现,虫害后萜类防御物质随幼虫GOX活性升高呈下降趋势。梢斑螟幼虫RNA和P含量比较发现,取食小卷蛾虫害球果、健康球果和新梢3种食料,均为梢斑螟3龄幼虫最高,5龄幼虫最小,差异极显著;但同一龄期,3种食料发育的幼虫,其RNA和P含量间无显著差异。这些结果说明,小卷蛾幼虫的先期危害,诱导了寄主防御,但后来的梢斑螟幼虫通过下唇腺GOX抑制了寄主的诱导防御,使其生长率与健康球果和新梢中的幼虫基本一致。     

瓜螟对寄生植物的选择和季节消长

瓜螟Diaphania indica Saunders是葫芦科植物的重要害虫.试验表明幼虫最嗜食冬瓜叶,其次是黄瓜、丝瓜和西瓜,对南瓜和蒲爪叶取食较少.雌蛾产卵时对植物有选择行为.在杭州每年从7月中旬起最多发生四代.十一年黑光灯下资料表明.灯下始蛾不早于七月上旬,终蛾不迟于十一月下旬,蛾蜂在八月下旬.卵、幼虫、预蛹和蛹历期(天)与日平均温度(℃)的关系分别是:Y_e=18.500—0.550X,Y₁=35.203—0.901X,Y_p＆p=59.705—1.785X.拟澳洲赤眼蜂(Trichogramma confusum)和瓜螟小室姬蜂(Scenocharops sp.)是首次报道的瓜螟寄生蜂,前者年平均寄生率达54.2±38.2%.另发现瓜螟绒茧蜂(Apanteles sp.)、扁股小蜂(Elasmus sp.)和病毒.     

三种泌盐红树植物对盐胁迫的耐受性比较

在盐度 0、5、15、2 5和 35 (% )下种植泌盐红树植物老鼠 (Acanthus ilicifolius)、桐花树 (Aegiceras corniculatum)和白骨壤(Avicennia marina)的繁殖体 ,以繁殖体萌发、幼苗生长、叶片泌盐量、叶片组织液盐含量和蒸腾蒸发量为指标 ,比较其对盐胁迫的耐受性。盐度提高对胎生种类桐花树和白骨壤的萌根速率无显著影响 ,但高盐度明显抑制非胎生种类老鼠的萌根。白骨壤的萌苗率不受盐度影响 ,但 2 5以上的盐度导致桐花树和老鼠的萌苗率下降。在盐度范围 5～ 35内 ,白骨壤幼苗的茎高生长随盐度的增加而减少 ,但减少量比桐花树小 ,而老鼠的减少量最大。老鼠因盐度提高而导致的叶片长度的减少量最大。在盐度提高的情况下 3种植物均具有泌盐量增加的效应 ,在任一盐度下泌盐能力的顺序均为白骨壤 >桐花树 >老鼠。淡水培养时 ,3种红树植物的叶片组织液盐含量 (约 2 % )均高于环境盐度 0。在盐度范围 5～ 35内 ,白骨壤的叶片组织液盐含量维持在较稳定的水平 (4 .3%～ 5 .0 % ) ,桐花树的变化范围为 2 .4 %～ 4 .5 % ,老鼠 2 .3%～ 5 .3%。淡水培养时 ,3种植物的蒸腾蒸发量类似 ,但盐性条件下白骨壤的蒸腾蒸发量显著高于桐花树和老鼠。随着盐度的增加 ,老鼠的蒸腾蒸发量下降最多。这些结果均表     

植食性昆虫的组成和波动对红树林群落演替的影响

为了解红树植物植食性昆虫在不同季节、不同潮位和不同寄主植物上的种类、密度差异和主要特点及其对红树植物树冠层所造成的影响,进而分析植食性昆虫对红树植物群落演替的影响,在山口红树林保护区设置5个断面,分别于雨季(7月)和旱季(2月),在每个断面的高潮位(H)、中潮位(M)和低潮位(L)针对不同植物抽样,统计叶片被食率,记录植食性昆虫的种类和密度。植食性昆虫共有23种,其中鳞翅目有13种,半翅目8种,鞘翅目1种,直翅目1种,真螨目1种。主要昆虫种类有海榄雌瘤斑螟(Ptyomaxia sp.)、毛颚小卷蛾(Lasiognatha cellifera)、白囊袋蛾(Chalioides kondonis)、广翅蜡蝉(Ricania sp.)、潜叶蛾(Phyllocnistis sp.)和蛎盾蚧(Lepidosaphes sp.)。雨季和旱季的密度均为广翅蜡蝉较高(7.31头·枝-1);不同断面红树植物叶片被食率旱季为C5C2≥C3≥C1,雨季为C5C2≥C3≥C1C4;不同潮位的叶片被食率旱季为中潮位≥高潮位低潮位,雨季为中潮位低潮位≥高潮位;不同树种的叶片被食率旱季为秋茄≥桐花树≥红海榄≥白骨壤,雨季为秋茄桐花树白骨壤≥红海榄≥木榄≥无瓣海桑≥海漆。红树植物叶片上的昆虫多为小型个体,植食性为主,多具有卷叶习性和粘附特征;蚂蚁、寄生蜂和捕食性蜘蛛等天敌类昆虫种类较少,昆虫密度一旦增加,较大可能会变成害虫,从而对树冠层的稳定造成较大的影响。植食性昆虫可在一定程度上推动红树林群落的演替。     

汞胁迫对白骨壤(Avicennia marina)幼苗生理生态的影响

为了解红树植物的重金属抗性机制,对白骨壤(Avicennia marina)幼苗进行不同浓度Hg2+(1、5、10、50、100 mg·L-1)的胁迫实验,测定并分析了Hg2+胁迫对白骨壤幼苗叶片的光合作用和抗氧化酶活性的影响.结果表明:叶片净光合速率随着胁迫时间的延长而降低,高浓度(≥150 mg·L-1)Hg2+胁迫下叶片的净光合速率低于中低浓度胁迫,且高浓度胁迫的叶片净光合速率在48 h后快速下降;叶片净光合速率与胞间二氧化碳浓度呈极显著负相关,叶绿素含量随Hg2+浓度的增加而降低.气孔导度在不同浓度胁迫下反应不同,低浓度Hg2+对白骨壤幼苗光合的影响可能是气孔因素,中高浓度Hg2+对白骨壤幼苗光合作用的抑制主要是非气孔因素.低浓度Hg2+胁迫,白骨壤幼苗叶片SOD、POD活性升高,表现了一定的抗逆性,而高浓度表现为抑制作用,基本在100 mg·L-1 Hg2+胁迫下活性达到最低值.说明Hg2+可以抑制白骨壤叶片的光合活性,高浓度Hg2+胁迫削弱了白骨壤的活性氧清除能力,植物极易受到伤害.     

乌蔹莓鹿蛾的生物学特性

乌蔹莓Cayratia japonica(Thunb.)Gagn.是一种多年生攀援性恶性杂草,对绿篱、草坪、观赏灌木危害较大。乌蔹莓鹿蛾Amatasp.是一种以乌蔹莓为食料的单食性昆虫,以老熟幼虫在残枝落叶上作茧越冬,翌年5月上中旬化蛹,中下旬羽化,每头雌蛾平均产卵块3个,每卵块有卵几十粒至100粒不等,平均每块含卵42粒,卵期7～9天,幼虫分5龄,历期14～18d,蛹期10～14d。在江苏扬州1年可发生不完全的4代。幼虫对乌蔹莓各器官的偏嗜性程度为:花蕾>叶>果。乌蔹莓鹿蛾对乌蔹莓有明显的控制作用。     

Two new species of Acizzia Crawford (Hemiptera: Psyllidae) from the Solanaceae with a potential new economic pest of eggplant, Solanum melongena

Two new species of Acizzia Heslop-Harrison (Hemiptera: Psyllidae) from the plant family Solanaceae in eastern Australia are described. Acizzia solanicola sp. n. can damage eggplant, Solanum melongena (Solanaceae), in commercial crops and gardens in eastern Australia. It is a new, potentially serious commercial pest species, of which the nymphs induce malformation of leaves, produce copious amounts of viscous waste and cause leaf wilting, premature leaf senescence and crop loss. These psyllids have a unique and characteristic method of disposing of honeydew and this is illustrated for the first time. Acizzia alternata sp. n. is recorded from the weed, wild tobacco bush, Solanum mauritianum , but appears to cause little damage. These comprise the first record of a pest psyllid on eggplant and the first record of Acizzia from the Solanaceae. The parasitoid, Psyllaephagus sp. (Hymenoptera: Encyrtidae), is recorded parasitising nymphs of A. solanicola sp. n., and is here proposed as a potential biological control agent against it.     

Prospects of using Metarhizium anisopliae to check the breeding of insect pest, Oryctes rhinoceros L. in coconut leaf vermicomposting sites

During vermicomposting of coconut leaves by the earthworm Eudrilus sp., Oryctes rhinoceros L. (rhinoceros beetle), an insect pest of palms, was found to breed in the decomposing organic material. Metarhizium anisopliae var. major was tried as a biocontrol agent for management of this pest. The effect of pathogen at spore loads of 10(3), 10(4) and 10(5) per 10 g of substrate was tested in laboratory on Eudrilus sp. kept with O. rhinoceros grubs and on Eudrilus sp. alone for the pathogenic capability of the fungus on the pest and its possible toxicity towards the vermin. The efficacy of the entomopathogen was also tested in the field in vermicomposting tanks. In laboratory bioassay, 100% mycosis of O. rhinoceros grubs could be obtained while the entomopathogen had no toxic effect on the earthworms. There was a positive change in the number and weight of the earthworms on treatment with M. anisopliae. In the field, application of M. anisopliae reduced O. rhinoceros grubs in the vermicomposting tanks upto an extent of 72%. In conclusion, M. anisopliae could effectively control O. rhinoceros in vermicomposting sites and was non-hazardous to the vermicomposting process as well as the Eudrilus sp.     

A new species of Chironomus Meigen, 1803 (Diptera,Chironomidae) from the southeast of Brazil

The article describes the larva, pupa, adults and karyotype of Chironomus reissi, sp. n., which live on leaf detritus beds of small temporary waters in the southeast of Brazil. The species belongs to the pseudothummi cytocomplex with the chromosome arm combination AE, BF, CD, G.     

Evaluation of spinning disc technology for the application of entomopathogenic nematodes against a foliar pest

Two spinning disc spray application systems, the Micron Herbaflex and Micron Ulva+, were assessed for their potential for the application of infective juveniles (IJs) of entomopathogenic nematodes (EPNs) against larvae of the diamondback moth (DBM), Plutella xylostella. The effect of initial concentration of IJs on subsequent infection was examined for three species of EPNs: Steinernema sp. (M87), Steinernema sp. (SSL85), and Heterorhabditis sp. Increasing the concentration of IJs generally resulted in a significant increase in both DBM mortality and the mean number of nematodes per larva following spray application with the Micron Herbaflex sprayer. Application with the Micron Ulva+ was examined using two different initial concentration of IJs, which generally resulted in an increase in DBM mortality and intensity of infection. The effect of changing the flow rate to the Ulva+ was also examined. This generally resulted in increased DBM mortality as flow rate was increased but there was little change in the mean number of nematodes per host larva. The effect of addition of a number of adjuvants to the spray solution on subsequent infection showed that DBM mortality by the IJs was not significantly affected but that the mean number of nematodes infecting was significantly enhanced by some of the adjuvants. Desiccation survival studies with IJs of Heterorhabditis sp. following application with both sprayers onto Chinese cabbage leaf discs, with or without the addition of an adjuvant, showed that the survival time of 50% of IJs was over 3 h. Infection of DBM larvae was also assessed following desiccation on Chinese cabbage leaf discs. High levels of infection were attainable, in terms of resultant DBM mortality, for at least 150 min following spray application.     

Parasitoid associated with Liriomyza huidobrensis (Diptera: Agromyzidae) outbreaks in tomato fields in Brazil

1. The knowledge of natural factors that affect pest populations is essential in predicting the occurrence of pest outbreaks and in developing integrated pest management programmes. Natural enemies, climatic elements and host plants are among the most important factors affecting pest dynamics.
2. Tomato (Solanum lycopersicum) is the second most consumed vegetable worldwide. The pea leaf miner Liriomyza huidobrensis (Diptera: Agromyzidae) is a major pest to the tomato in Brazil.
3. This study aimed to determine the main natural factors that regulate L. huidobrensis populations in tomato fields in Brazil.
4. Liriomyza huidobrensis densities were evaluated by directly counting the number of active mines on the basal leaf of the middle section of the plant canopy, and predators and parasitoids were assessed using the leaf‐beating‐against‐a‐tray technique. Eight commercial tomato fields were assessed over two years. The phenological growth stages of the tomato plants (vegetative and reproductive) were noted during the assessments.
5. Liriomyza huidobrensis populations peaked between the middle and end of the planting season.
6. Opius sp. (Hymenoptera: Braconidae) was the main natural enemy of L. huidobrensis.
7. Our results suggest that phenological growth stage and Opius sp. are associated with population dynamics of L. huidobrensis in tomato fields.
8. Therefore, integrated pest management programmes should aim to preserve populations of the parasitoid Opius sp.

     

用ELISA方法研究稻田节肢动物的食物关系

应用酶联免疫吸附试验双抗体夹心法,研究了稻田节肢动物,包括19种捕食性天敌、4种主要水稻害虫及1种中性昆虫之间的食物关系。在检测的19种捕食者中,有15种捕食了白背飞虱,11种捕食了褐飞虱。其中食虫沟瘤蛛、拟水狼蛛、八斑鞘蛛、粽管巢蛛、四斑锯螯蛛和拟环纹豹蛛对两种稻飞虱的捕食阳性率较高。有7种捕食了稻纵卷叶螟幼虫,其中粽管巢蛛、褶管巢蛛、拟环纹豹蛛、青翅蚁形隐翅虫和印度细颈步甲的捕食阳性率较高。拟环纹豹蛛、浙江豹蛛和拟水狼蛛对稻蝗若虫有较高的阳性率。13种捕食者捕食了摇蚊,摇蚊作为替代或补充猎物,对稻田捕食性节肢动物亚群落的重建和发展具有重要意义。在实验检测的基础上,构建了被检测节肢动物猎物与捕食者间的食物关系图。     

A review of the biology and control of the vine weevil, Otiorhynchus sulcatus (Coleoptera: Curculionidae)

At the turn of the century, damage by Otiorhynchus sulcatus was sporadic and limited to small areas. Increasing horticultural intensification and the adoption of husbandry techniques favourable to the weevil, such as the use of polythene mulches, increased its pest status. The development of the early inorganic pesticides reduced the number of serious outbreaks of this pest and weevil control was further improved by the development of the persistent organochlorine insecticides in the 1940's. The banning of a number of the more persistent insecticides over recent years has now left the horticultural industry in a very vulnerable position. O. sulcatus is now a pest on a range of horticultural crops throughout the temperate regions of the world. Infestations are most common in Europe (where it originated) and the USA, and nearly 150 plants species have been identified as potential hosts to O. sulcatus. Damage is most frequently caused by the root feeding larval stage. Populations as low as one larva plant can kill sensitive species such as Cyclamen. Severe damage by the leaf feeding adults is less common, although low levels of damage or contamination by adults may be unacceptable in certain situations. There is one generation a year. Oviposition by the flightless parthenogenetic females occurs over the summer months with oviposition rates of c. 500 and 1200 eggs adult^-1for outdoor and laboratory populations, respectively. O. sulcatus mainly overwinters as larvae, although significant numbers of adults may survive in areas where winter temperatures are not too severe. A number of natural enemies, such as hedgehogs, frogs and predatory beetles, help to maintain O. sulcatus populations at a low level in natural environments, but they are less successful in intensive horticultural systems where persistent chemicals have been heavily relied on to maintain the population below the economic threshold level. Increasing environmental concern is now forcing growers to consider new pest control strategies. Controlled release formulations of non-persistent products, such as fonofos and chlorpyrifos, have shown potential as control agents for O. sulcatus larvae. Biological control agents, such as insect parasitic nematodes, have been developed commercially and new microbial control agents are in the process of development. Most of the new control products are directed towards control of O. sulcatus larvae. Adult vine weevils are nocturnal and a much more difficult target for the new control agents. It is likely that an integrated approach to pest control will be required to maintain O. sulcatus populations below their economic threshold level.