英德跳生物学特性和防治研究

英德跳是我国森林昆虫竹节虫目的一新虫种。在广东省英德县首次发现危害黎蒴栲林成灾得名。若虫和成虫危害黎蒴栲为主的壳斗科树叶，以成虫危害最烈。该虫在英德县１ａ发生２～３代，世代重叠。以第１、２代成虫产的卵在枯枝落叶层下越冬，翌年２月下旬卵开始孵化，５月中、下旬为越冬代成虫高峰期。在５月上、中旬使用３％６６６烟剂１５ｋｇ／ｈｍ２防治，效果达８５％以上，使用绿僵茵１．５×１０１３个／ｈｍ２孢子防治，效果可达７０％以上。     

诱发桃形李煤污病的主导因子和防治方法

诱发桃形李煤污的主导因子是梨园蚧危害，该虫在浙江浦江１年３代，以受精雌成虫越冬。防治方法：２月中下旬，用３￣５度石硫合剂全面喷洒；４月中下旬，５０％杀螟松８００￣１０００倍液喷洒；６月中下旬，５０％甲基托布津０００倍液喷洒；１１月份，５０％久效膦６￣１０倍涂干。     

榆少锤角叶蜂的研究

榆少锤角叶蜂是严重危害榔榆、白榆叶片的新害虫。该虫１ａ发生１代，老熟幼虫钻入杂灌草丛根际或疏松浅土层中结茧，以预蛹越冬。翌年３月下旬化蛹，４月上旬羽化交尾交卵，幼虫期为３２．７８±２．２７ｄ，每头幼虫平均取食量为２５９０３．８３±６７７８．５５ｍｍ２，５月下旬相继老熟下树结茧过夏越冬。成虫产卵主要在低矮小树或大树下层枝条叶片上。该虫体表光滑裸露，抗药性弱，只要防治时机恰当，一般农药均可取得良好效果。以５％氯氰菊脂、２．５％敌杀死１∶３０００或８０％敌敌畏、９０％晶体积敌百虫１∶８００为佳。     

竹箩舟蛾的研究

竹箩舟蛾是竹子的重要食叶害虫,分布于我国南方产竹各省,在浙江省１ａ３～４代,均以蛹于土表下越冬。成虫发生期分别为４月上旬～５月上旬、６月上旬～７月上旬、７月下旬～８月下旬、９月下旬～１０月中旬。幼虫危害期分别为４月下旬～６月中旬、６月中旬～８月上旬、８月中旬～１０月上旬,以第３代蛹越冬者幼虫可延至１０月下旬,第４代为１０月中旬、１１月下旬。第３代幼虫各龄食叶量分别为１．５７、７．７３、１６．３６、５７．０２、５７９．７８ｃｍ＾２,幼虫期共取食竹叶６６２．４６ｃｍ＾２。雌性幼虫期食叶量比雄性多１２％～１５％,每头成虫产卵量为１６１～２８６粒。天敌有赤眼蜂、黑卵峰、姬蜂、寄蝇等。并提出了相应的防治方法。     

紫薇绒蚧的发生规律与防治

紫薇绒蚧又名石榴绒蚧，主要危害紫薇、石榴，是城市园林观赏树木的主要害虫之一，以雌成虫及若虫危害紫薇的嫩枝，受害轻者树势衰弱，严重时枝条上布满虫体刺吸植物汁液，并导致煤污病，造成紫薇黄叶、落叶，枝条干枯。近几年，紫薇绒蚧在我区紫薇树上发生严重。据调查，一般株害率在６０％～７０％，严重的株害率达１００％，极大的影响了紫薇树的生长及观赏价值。一、发生规律紫薇绒蚧在本地１年发生２代，以第２代的２龄幼虫在紫薇枝条皮缝皮下或空蜡囊中越冬。次年３月中下旬越冬若虫开始取食发育，４月中旬雌雄明显分化，４月底５月初雄虫羽化，交尾后死亡，５月中旬雌虫开始产卵，５月下旬进入产卵盛期，卵期５～７天，６月上旬为卵孵盛期。若虫孵化后，在枝干树皮缝隙及不光滑的部位定居，７～８天后进入２龄期，２龄若虫在枝干上寻找幼嫩部位定居。７月中旬出现第１代成虫，８月上中旬进入２代若虫孵化盛期，１０月下旬以２龄若虫越冬。二、防治措施紫薇绒蚧成虫有蜡质分泌物，药剂防治效果差。因此，必须根据其生物学特征和发生规律，抓住关键时间，进行综合防治。一是加强检疫，调运苗木时要严格检疫，防止紫薇绒蚧蔓延。二是结合冬季修剪，彻底剪除带虫枝条，消灭越冬虫源。三是在紫薇树发芽...     

花椒跳甲生物学特性及防治初步研究

花椒跳甲Ｐｏｄａｇｒｉｃｏｍｅｌａｓｈｉｒａｈａｔａｉ（Ｃｈａｊｏ）在河南林州一年发生２代，以成虫在土壤内越冬，翌年４月上旬开始出土，５月下旬产卵，６月上旬第１代幼虫开始危害，危害期１３一２０天。９月中旬出现第２代幼虫，１０月上旬第２代成虫羽化，取食１０一１５天，于１０月中下旬开始入土越冬。化学防治在成虫产卵盛期进行，用溴氰菊酯、杀灭菊酯、水胺硫磷喷雾效果可达９０％以上。     

黄杨粕片盾蚧生物学特性,发生动态及其防治研究

黄杨粕片盾蚧在北方严重为害小叶黄杨，１ａ发生２代，多以成虫、部分以２龄若虫越冬。第１代１龄若虫高峰日为５月１２日－６日，第２代１龄若虫盛期为７天下旬，以第１代发生较为整齐。该蚧虫在小叶黄杨上主要分布于１ａ生枝叶，并以１龄若虫逐年向新生枝呈主动扩散，在较大范围内扩展较快，在３－４ａ内可造成严重为害。对其防治的关键时期是１龄若虫活动期和雄成虫期。喷洒４０％氧化乐果１０００倍液、洗衣粉５００倍液防治１龄     

东方绛蚧生物学及防治研究

东方绛蚧ＫｅｒｍｅｓｏｒｉｅｎｔａｌｉｓＳｈｉｅｔＬｉｕ一年１代，１０月中、下旬以２龄若虫在芽基、枝干裂缝等部位越冬。第二年３月下旬开始为害，雌若虫在原处脱皮２次进入成虫期，雄若虫转移到枝干或地面杂草处作茧，经预蛹和蛹期，５月上旬羽化为成虫，５月下旬是雌成虫产卵和卵孵化高峰。１龄若虫初期是化学药剂防治的有利时机     

云南松纵坑切梢小蠹危害及生物学特性研究

纵坑切梢小蠹在云南分布很广，８０年代以来，在昆明，红河，楚雄３地，州３０个县的云南松人工林内猖獗危害，直接经济损失６０００余万元。该虫在云南１ａ一代，全年危害，无明显的越冬现象，每年５￣１１月蛀梢，１１￣翌年５月蛀干，树皮下各虫态种群高峰期出现在２￣５月，此时是清理蠹害木的最佳时期，成虫干转梢及由梢转干在林间扬飞期１￣１４ｄ，集中扬飞３￣４ｄ，扬飞期对防治成虫有重要意义。     

沙棘蛀士害虫柳蝙蛾的生物学特性及防治

柳蝙蛾是一种新的沙棘蚊干害虫,属鳞翅目,蝙蝠蛾科。在黑龙江省绥棱地区一般２年发生１代,少数１年发生１代,以孵和幼虫越冬,越冬幼虫从４月下旬开始危害至７月下旬;越冬卵孵化后,幼虫７月中旬至８月上旬开始钻蛀危害至１０月,然后以幼虫在树干基部越冬。采用２０％的速灭杀丁乳油,８０％敌敌畏乳油,在幼虫钻蛀前进行地面喷药防治,结合虫道“注液法”防治,防效可达９３．３％－１００．０％。     

Improving the evaluation of multiple-dowel-type connection strength

Our study focuses on predicting the ultimate short-term load carrying capacity of timber-to-timber connections with dowel-type fasteners. The wide range of possible configurations in practice makes the resolution of these values by tests unrealistic. Moreover, different current regulations do not consider some specific failure mechanisms. In many countries, the reduction of resistance involved by this phenomenon is taken into account by considering an effective number of dowels (n_ef) smaller than the actual number of dowels (n) in the connection. However, these different regulations disagree on the values of n_ef and on other points (spacing, partial coefficient of security, formulas). These discrepancies in design rules invite the fundamental research on this topic and, therefore, new methods are sought in order to estimate the load carrying capacities of the connections. In the light of these, our approach consists of predicting the load carrying capacity with the neural network numerical tool. The results obtained by this analysis tool are satisfactory, although the model remains complex. Subsequently, we focus on the simplification of this numerical model with classical regression techniques in order to implement it in a design code.     

<Emphasis Type="Italic">Ophiostoma</Emphasis> species associated with bark beetles infesting three <Emphasis Type="Italic">Abies</Emphasis> species in Nikko,Japan

Ophiostoma species were isolated from bark beetles and Abies mariesii, A. veitchii and A. homolepis attacked by the beetles in Nikko, Tochigi, central Honshu, Japan. One to two Ophiostoma species were frequently isolated from each species of bark beetle. Ophiostoma subalpinum was the most common associate of Cryphalus montanus. Ophiostoma sp. B as well as O. subalpinum was a common fungus associated with Polygraphus proximus. Ophiostoma europhioides was isolated from Dryocoetes hectographus and D. autographus as one of the common associates. Ophiostoma sp. J and Ophiostoma sp. S were frequently isolated from D. autographus and D. striatus, respectively. These fungi seem to have specific relationships with particular bark beetles. Ophiostoma sp. B, Ophiostoma sp. J and Ophiostoma sp. S have unique morphological characteristics and appear to be new species. Five trees of A. veitchii, approximately 43 years old, were inoculated with five Ophiostoma species to assess the relative virulence of the fungi. Ophiostoma subalpinum, Ophiostoma sp. B, and O. europhioides had relatively higher virulence than the other species studied.     

Decomposition and nutrient loss from prunings of different contour hedgerow species in tea plantations in the sloping highlands of Sri Lanka

Contour hedgerows of multipurpose tree species in the sloping tea lands of Sri Lanka are expected to reduce soil erosion and also add significant amounts of plant nutrients to the soil via periodic prunings. The objective of this experiment was to characterize the biomass decomposition pattern and quantify the amount of nutrients added through prunings of six tree species (Calliandra calothyrsus, Senna spectabilis, Euphatorium innulifolium, Flemingia congesta, Gliricidia sepium and Tithonia diversifolia) currently being used in hedgerows associated with tea. Withered leaf and stem prunings (50 g) were enclosed in 2-mm litter bags, placed at 5-cm depth and retrieved after one, three, six, nine and 12 weeks. Loss of initial dry weight, N, P and K was measured. Single exponential decay function adequately described both dry weight and nutrient loss. Tree species differed significantly in their rate of breakdown with decomposition constants (k) varying from 0.0299 to 0.2006 week⁻¹ for leaves and from 0.0225 to 0.0633 week⁻¹ for stems. Gliricidia showed the highest k for leaves with the rest in the following descending order: Senna > Tithonia ≥ Euphatorium > Calliandra > Flemingia. A similar pattern was observed for loss of all nutrients with Calliandra and Flemingia always having lower k values than the rest. Although N immobilization was not observed, immobilization of P and K was observed during the first week of incubation in some species, particularly in stem prunings. Annual biomass of prunings differed significantly between tree species in the following descending order: Calliandra > Senna > Flemingia > Tithonia > Gliricidia > Euphatorium. Calliandra added the greatest amount of nutrients annually to the soil with Euphatorium adding the least. Calliandra prunings provided the annual total K requirement and 49% of the N requirement of mature tea. However, none of the species provided more than 5% of the P requirement. It is concluded that among the tree species tested, Calliandra and Flemingia are the most suitable for contour hedgerows in tea plantations of this agroclimatic region because of their higher soil nutrient enrichment capacity and slower decomposition rates which would minimize leaching losses. This revised version was published online in June 2006 with corrections to the Cover Date.     

Parasitic Ichneumonoidea on the horse chestnut leaf miner, Cameraria ohridella (Lepidoptera: Gracillariidae) in Slovakia

Parasitic Hymenoptera from the suprafamily Ichneumonoidea attacking the horse chestnut leafminer Cameraria ohridella Deschka & Dimic (Lepidoptera: Gracillariidae) were studied in southwest Slovakia during 2000 and 2001. The search for such species resulted in the determination of eight ichneumonid species, Gelis agilis (Fabricius), Itoplectis alternans (Gravenhorst), I. clavicornis (Thompson), I. maculator (Fabricius), Scambus annulatus (Kiss), S. brevicornis (Gravenhorst), Zatypota percontatoria (Müller), Adelognathus sp. and a braconid Colastes braconius Haliday. The most abundant species was S. annulatus. All these species recorded are polyphagous and often facultative hyperparasitoids, except C. braconius, which departs from this norm in not being hyperparasitic. The presence of more diversified native parasitoids and hyperparasitoids from the Ichneumonoidea predicate a slow successive adaptation of the parasitoid fauna to the invasive host, Cameraria ohridella.     

Potential to harness superior nutritional qualities of exotic baobabs if local adaptation can be conferred through grafting

Baobab leaves form an important part of the local diet in Sahel countries and elsewhere in Africa. Existing leaf nutritional data and agroforestry performance information are based solely on Adansonia digitata L., the baobab of continental Africa. The introduction potential of Adansonia species from the center of diversity in Madagascar and from Australia remains untapped. To assess this potential, the mineral contents and B₁ and B₂ vitamin levels of dried baobab leaves were determined for five-year old trees of A. digitata, A. gibbosa (A. Cunn.) Guymer ex D. Baum, A. rubrostipa Jum. & H. Perrier (syn. A. fony Baill.), A. perrieri Capuron and A. za Baill. grown in an introduction trial in Mali. Nutritional data were evaluated against survival and vigor to identify promising germplasm. Leaf vitamin and crude protein contents were highest in the Madagascar species, especially A. rubrostipa (B₁ 88 mg 100 g⁻¹, B₂ 187 mg 100 g⁻¹, protein 20.7% dry weight). However, the local species far outperformed the introductions in survival, tree height, basal diameter and resistance to termites. We suggest grafting as a way of harnessing the vigor of well-adapted local baobab varieties to the superior nutritional profiles of A. rubrostipa and others. Cross-species grafting tests in Adansonia were successful, thus creating new agroforestry possibilities with different scion/rootstock combinations.     

<Emphasis Type="Italic">Bursaphelenchus mucronatus</Emphasis> (Nematoda: Aphelenchoididae) vectored by <Emphasis Type="Italic">Monochamus </Emphasis><Emphasis Type="Italic">urussovi</Emphasis> (Coleoptera: Cerambycidae) in Hokkaido,Japan

Bursaphelenchus mucronatus Mamiya et Enda has been recovered for the first time from adults of the cerambycid beetle, Monochamus urussovi (Fischer), in Hokkaido, Japan. The nematode was also recovered from the inner bark of Picea jezoensis (Siebold et Zuccarini) Carrière and Abies sachalinensis (Fr Schmidt) Masters infested with M. urussovi larvae. PCR–RFLP analysis indicated that B. mucronatus in Hokkaido is the European type.     

基于cpDNA rps16序列分析兰考泡桐与白花泡桐和毛泡桐的遗传关系

【目的】通过测序法分析兰考泡桐与白花泡桐和毛泡桐在叶绿体rps16序列上的遗传差异,旨在分析三者之间在叶绿体基因上的变化特点和规律,探讨其种间的遗传关系。【方法】选取兰考泡桐、白花泡桐和毛泡桐各15个样本,对其提取的DNA用PCR扩增获得特异片段,并将其纯化与测序。利用软件Clustal X 2.0对所得序列进行排序;运行MEGA 4软件,进行多序列比对,分析其序列特征,并计算出K2P遗传距离。【结果】(1)对获得的rps16序列进行测定分析,得兰考泡桐序列长度分别为932 933 bp;白花泡桐序列长度为932 bp;毛泡桐序列长度分别为916918 bp。对所得rps16序列进行排序后的长度为938 bp,平均GC含量为34.31%。3个种所代表的个体之间共有10个变异位点,占整个序列长度的1.07%。其中有9个变异位点属于碱基插入或缺失类型,占变异位点总数的90%,占整个序列长度的0.96%。有1个变异位点属于碱基替换类型,占整个变异位点总数的10%,占整个序列长度的0.11%。(2)整个rps16片段的序列共有10个变异位点,其中兰考泡桐与白花泡桐在总的变异位点上,具有一致的碱基位点9个,占总变异的90%。而兰考泡桐与毛泡桐相比,没有相同的碱基。【结论】根据三种泡桐的rps16序列的序列特征和变异位点的分析,表明在叶绿体遗传方面,兰考泡桐具有与白花泡桐更多相似的遗传物质,其亲缘关系较近。综上所述,推测兰考泡桐与白花泡桐可能来自同一母系遗传。     

Rehabilitation of diseased cacao fields in Peru through shade regulation and timing of biocontrol measures

The objective of this case study was to test the effectiveness of biocontrol for the rehabilitation of abandoned, diseased (moniliasis, witches' broom and black pod) cocoa and to develop testable hypotheses regarding the effect of shade and biocontrol timing. Three trial fields differed in their shade regimes. Biocontrol was administered starting either at flowering or pod filling. Disease incidence and yield were compared with cultural control alone. Biocontrol reduced moniliasis from 49% to 25%, independent of the shading regime and application time. Witches' broom was most severe without shade and unaffected by biocontrol. No significant effects on black pod were observed. Although biocontrol increased percentage healthy fruit independent of shading and timing, only the shaded plot with biocontrol from flowering onwards responded with increased yield. Our hypothesis is: 'In the rehabilitation of abandoned cacao, only fields under sustainable shade management and early onset of biocontrol can realise their production potential.' This revised version was published online in June 2006 with corrections to the Cover Date.     

Populations of adult fungus gnats and shore flies in British Columbia container nurseries as related to nursery environment,and incidence of fungi on the insects

Adult fungus gnat and shore fly populations were monitored in four container nurseries near Victoria, British Columbia. In general, populations of both insects were larger in summer than in winter. Also, both insects were more abundant in the nursery with a plastic-covered, soil floor, which favored moisture accumulation and build up of algae, liverworts and mosses, than in nurseries with other types of floors such as cement. Results of fungus isolations revealed that gnats and flies both harbor the seedling pathogens Botrytis cinerea and species of Fusarium and Phoma, plus several non-pathogenic fungi. The results are discussed in relation to nursery sanitation practices, their effects on gnat and fly populations, and some possible roles of these insects in seedling disease epidemiology.     

Insecticidal activity of certain medicinal plants

The methanol extracts of eight species of medicinal plants were tested for insecticidal activity in third instar larvae of Egyptian cottonworm (Spodoptera littoralis). All extracts showed a certain degree of larval toxicity. The extracts of Ocimum basilicum, Origanum majorana and Salvia officinalis appeared to be highly toxic. The extracts significantly affected the growth indexes [relative growth rate (RGR), efficiency of conversion of ingested food (ECI), efficiency of conversion of digested food (ECD)].