地肤提取物对山楂叶螨体内几种酶活性的影响

采用生化方法测定地肤三氯甲烷提取物对山楂叶螨体内谷胱甘肽-S-转移酶、羧酸酯酶、单胺氧化酶、Ca2 -ATP酶活性的影响.结果表明:地肤提取物处理山楂叶螨后,螨体内谷胱甘肽-S-转移酶、羧酸酯酶等解毒酶活性被激活,谷胱甘肽-S-转移酶、羧酸酯酶都是昆虫体内重要的代谢解毒酶系,它们参与了昆虫对内源或异源有毒物质的代谢解毒,特别是对杀虫剂的解毒,这表明地肤提取物中存在对山楂叶螨有毒的物质,从而引起了螨体的解毒作用,来维持正常的生理功能.而单胺氧化酶、Ca2 -ATP酶的活力受到一定程度的抑制.Ca2 -ATP酶的被抑制,可能会破坏细胞内外Ca2 的平衡,影响神经细胞的兴奋和传导,引起神经传递的阻断;单胺氧化酶被抑制,使螨体内神经胺积累,也会造成神经传递的阻断,从而导致螨体的死亡.以上结果表明地肤作为新型植物源农药具有良好的开发前景.     

马尾松针叶中挥发性成分的鉴定及其对马尾松毛虫的触角电位反应

马尾松Ｐｉｎｕｓ ｍａｓｓｏｎｉａｎａ针叶的挥发物由溶剂提取和真空蒸馏制得。用气相色谱和气相色谱－质谱，由挥发物中鉴定出了２０种成分。它们主要是单萜烯、单萜烯醇、单萜烯乙酸酯和倍半萜烯。用正常和剪除触角的雌蛾研究针叶挥发物在马尾松毛虫Ｄｅｎｄｒｏｌｉｍｕｓ ｐｕｎｃｔｕｔａｓ产卵场所选择中的作用。试验表明正常雌蛾在针叶上的产卵量要比剪除触角的高得多。触角电位（ＥＡＧ）研究表明无论是交配的还是未交配     

Plant species diversity of homegardens of Cuba and its significance for household food supply

The cultivation of different plants in homegardens for self-sufficiency has a long tradition in Cuba, but knowledge about homegardens in Cuba is small. To analyse this more deeply, cultivated plants of 31 homegardens were surveyed in three villages in eastern Cuba in 2001. Two of the study villages were located in a humid area with an annual precipitation of about 2200 mm. The third village was situated in a semiarid area with about 450 mm precipitation. The plants studied in the homegardens included those for human consumption such as fruits, vegetables, tubers and cereals as well as spices and medicinal plants. In total, 101 different plant species were found with an average number of 18 to 24 species per homegarden for the three villages. A broad range of species was found in all villages, because irrigation is used under semiarid conditions, which lead to a relative high similarity in species composition between the villages. But, also differences due to the climatic situation became evident, particularly with the medicinal plants. In general, homegarden production provided a broad and diverse basis for self-sufficiency of the households. Although homegarden production showed to be only a small source of income, it is particularly important because of low-paid outside work and minimal food provision of the state.This revised version was published online in November 2005 with corrections to the Cover Date.     

Insect inhabitants of old larval galleries of<Emphasis Type="Italic"> Saperda populnea</Emphasis> (L.) (Coleoptera: Cerambycidae) in Bulgaria

The complex of insect inhabitants of old larval galleries of Saperda populnea (L.) (Coleoptera: Cerambycidae) was studied during the period 2000–2003 in 18 localities in Bulgaria. As a result, 32 insect species were reared from old S. populnea galls: Metopoplax origani (Kolenati) (Heteroptera: Lygaeidae), Malachius sp. (Coleoptera: Malachiidae), Agrilus pratensis pratensis (Ratzeburg) (Coleoptera: Buprestidae), Xylocleptes bispinus (Duftschmidt) (Coleoptera: Scolytidae), Crossocerus cetratus (Shuckard), Crossocerus megacephalus (Rossi), Crossocerus nigritus (Lepeletier & Brullé), Crossocerus acanthophorus (Kohl), Passaloecus brevilabris Wolf, Passaloecus gracilis (Curtis), Psenulus schencki (Tournier), Solierella compedita compedita (Piccioli), Trypoxylon figulus figulus (Linnaeus), Trypoxylon fronticorne fronticorne Gussakovskij (Hymenoptera: Crabronidae), Cleptes schmidti Linsenmaiser, Trichrysis cyanea (Linnaeus) (Hymenoptera: Chrysididae), Clistopyga incitator (Fabricius), Ctenochira sanguinatoria (Ratzeburg), Liotryphon crassisetus (Thomson), Nemeritis fallax (Gravenhorst), Mesochorus georgievi Schwenke, Campoletis sp. (Hymenoptera: Ichneumonidae), Charmon extensor (Linnaeus) (Hymenoptera: Braconidae), Eupelmus urozonus Dalman (Hymenoptera: Eupelmidae), Perilampus aeneus (Rossius) (Hymenoptera: Perilampidae), Trichiocampus grandis (Lepeletier) (Hymenoptera: Tenthredinidae), Janus luteipes (Lepeletier) (Hymenoptera: Cephidae), Cydia corollana (Hübner) (Lepidoptera: Tortricidae), Fiebrigella brevibucca (Duda) (Diptera: Chloropidae), Eustolomyia hilaris (Fallén) (Diptera: Anthomyiidae), Senotaina sp. (Diptera: Sarcophagidae) and Heringia vitripennis (Meigen) (Diptera: Syrphidae). Amongst them, 27 species were established as new inhabitants of old S. populnea galls. Five species (C. schmidti, N. fallax, M. georgievi, P. aeneus and J. luteipes) were recorded for the first time in Bulgaria. The dwellers of old S. populnea galls belong to the following ecological groups: insects using galls as a place to develop (3 species); insects nidificating in empty galls (10 species); insects using old galls as a pupating place (1 species); insects using empty galls as overwintering shelters (3 species); predators and parasites of primary dwellers of empty galls (13 species); or insects with uncertain ecological status (2 species).     

The Role of Mangroves in Retaining Penaeid Prawn Larvae in Klang Strait,Malaysia

The mangrove-fringed Klang Strait, Malaysia, retains approximately 65 billion penaeid prawn larvae annually prior to their settlement in coastal nursery grounds. This phenomenon appears to be due principally to tidal currents and lateral trapping in mangrove-fringed channels, the wind playing an insignificant role.     

Evaluation of Bacillus thuringiensis Berliner as an alternative control of small hive beetles, Aethina tumida Murray (Coleoptera: Nitidulidae)

Small hive beetles, Aethina tumida Murray, are parasites and scavengers of honeybee colonies, Apis mellifera L., and have become an invasive species that can cause considerable damage in its new distribution areas. An effective subspecies of Bacillus thuringiensis Berliner (=Bt) would provide an alternative to chemical control of this pest. Therefore, we tested three different Bt strains [B. thuringiensis, var. aizawai (B401^®), B. thuringiensis var. kurstaki (Novodor^®) and B. thuringiensis var. San Diego tenebrionis (Jackpot^®)] and Perizin^® (3.2% coumaphos), each applied on combs with a pollen diet fed to pairs of adult beetles. This evaluates the products for the suppression of successful small hive beetle reproduction. While none of the tested Bt strains showed a significant effect on the number of produced wandering larvae, we could confirm the efficacy of coumaphos for the control of small hive beetles. We further show that it is also efficient when applied with a lower concentration as a liquid on the combs. We suggest the continued search for efficient Bt strains naturally infesting small hive beetles in its endemic and new ranges, which may become a part of the integrated management of this pest.     

Parasitoid complex (Hymenoptera, Braconidae, Aphidiinae) of Aphis craccivora Koch (Hemiptera: Aphidoidea) in Iran

The parasitoids (Hymenoptera, Braconidae, Aphidiinae) of the cowpea aphid, Aphis craccivora Koch, were investigated throughout two far distant provinces, Tehran and Sistan-Baluchestan. Colonies of the cowpea aphid were collected from different host plants and reared under laboratory conditions until the parasitoids emerged. The aphids were parasitized by an expected range of parasitoids. The species were Aphidius colemani Viereck, Lysiphlebus fabarum (Marshall), Lysiphlebus confusus Tremblay and Eady, Lysiphlebus testaceipes (Cresson), Binodoxys acalephae (Marshall), Binodoxys angelicae (Haliday), Praon volucre (Haliday) and Ephedrus persicae Froggatt. L. testaceipes is reported here for the first time in Iran. The most common species was L. fabarum followed by B. acalephae and L. confusus. A key is provided for identification and host plant associations are considered.     

The role of competitors for <Emphasis Type="Italic">Chrysomela lapponica</Emphasis>, a north Eurasian willow pest,in pioneering a new host plant

The Palaearctic leaf beetle Chrysomela lapponica usually feeds upon willows in the northern region of its occurrence. However, in Central Europe, some populations are known that have specialised on birch. In this study, we investigated the significance of other herbivores occurring together on the same host plants as possible exploitative competitors of C. lapponica. Two populations were studied: a population from Finland specialised on the willow Salix borealis, and a population from the Czech Republic, specialised on the birch Betula pubescens. Abundances of folivorous and suctivorous insects on both host plants were recorded at both population sites. The willow leaf beetle Phratora vitellinae was the most abundant herbivorous insect at both study sites on willow. A field study was conducted to examine the effects of P. vitellinae on the performance of C. lapponica. The presence of P. vitellinae larvae on the same twig upon which C. lapponica larvae were feeding did not affect increase of body weight in C. lapponica larvae. Thus, the high resource availability of both willows and birches suggest that interspecific competition is unlikely to be a selection factor driving the evolution of host shift in C. lapponica.     

危害云杉的卷蛾三新种

青海云杉是甘肃省祁连山林区的主要树种，曾遭受多种害虫侵害，经作者研究发现其中有卷蛾三新种，本文对它们进行比较详尽的新种记述。     

Tree cavities in riverine forests: What determines their occurrence and use by hole-nesting passerines?

We assessed: (1) the relative importance of different macro- and microhabitat characteristics for explaining the occurrence of tree cavities and their occupancy by hole-nesting passerines and (2) the role of woodpeckers as keystone species in riverine aspen and birch stands in central Estonia. In 1999–2003, multiple surveys were carried out in 16 stands with a total area of 104 ha. Of the 713 tree-holes found, 483 were considered suitable for secondary cavity-nesters. The mean density was 4.1 ± 3.0 (S.D.) suitable cavities ha⁻¹ (including 2.0 ± 1.3 suitable for hole-nesting passerines). Woodpeckers had excavated 88% of suitable cavities. The density of breeding woodpeckers explained 78% of variance in the density of woodpecker-excavated cavities (mean = 28 holes per pair) and 51% of natural cavities. Woodpecker-excavated and natural cavities occurred in very similar conditions, determined mostly by tree species, decay and size, stand type, as well as the vicinity of other cavities. Ninety-six of 161 occupancy cases of cavities were by passerines, which – probably to reduce the risk of nest predation or physical destruction – preferred small natural cavities in live trees. We conclude that riverine areas are important centres of cavity supply in forested regions and the value of woodpeckers as keystone species comes mostly from the large quantity, but not quality, of the cavities they provide. The results imply that: (1) for cavity-nesters, large (DBH > 30 cm) broadleaved trees, both live and dead, are the most important to retain during forestry operations in hemiboreal riverine forests and (2) woodpecker censuses may indicate cavity abundance, particularly if woodpecker-holes dominate among all cavities.