植物与草食动物之间的协同适应及进化

通常协同进化是指一个物种 (或种群 )的遗传结构由于回应于另一个物种 (或种群 )遗传结构的变化而发生的相应改变。广义的理解 ,协同进化是相互作用的物种之间的互惠进化。生物之间、特别是植物与草食动物之间的协同适应与进化 ,已经成为生物进化、生态、遗传等学科十分关注的问题 ,可能成为生物学中各学科研究的交汇点或结点。作者具体阐述了 :(1)生物之间协同进化的研究意义 ,包括对生物学与生态学的价值 ;(2 )生物之间协同进化研究的限制或困难 ,诸如时间、研究对象、进化等级尺度和研究方法的限制 ;(3)植物与草食动物之间协同进化的主要研究对象 (系统 ) ,即昆虫传粉系统、昆虫诱导植物反应系统、种子散布系统、以及大型草食动物采食与植物反应系统 ;(4 )植物与草食动物之间协同进化的主要研究内容 ,包括适应特征 (性状 )——物种的可塑性 ,以及适应机制——物种适应过程与策略两个方面 ;(5 )植物与草食动物之间协同进化研究的存在问题及研究方向     

植食性哺乳动物与植物协同进化研究进展

从动物-植物协同进化模式,植物对动物采食反应及动物对植物防卫的适应对策等方面综述了以植物次生化合物为媒介的植食性哺乳动物-植物协同进化的研究进展,动物与植物的协同进化模式包括成对协同进化,扩散协同进化,躲避-辐射协同进化,多样性的协同进化,平行分枝进化,互惠进化等模式,植物不仅以超补偿反应,物理防卫作为对植食性动物采食的应答,延长植食性动物的觅食时间,降低植食性动物的觅食效率,更能以其派生的次生化合物抑制动物的摄食,进而影响其消化,代谢及生长等生理生态特征,动物通过改变觅食行为,调整对各食物项目的相对摄入量,减少次生化合物的摄入量,动物还通过氧化,还原,络合,改变消化道内环境,形成相应的降解酶,改变代谢率等途径降低次生化合物对其的负作用。     

Six new species of Philiris R?ber, 1891 (Lepidoptera,Lycaenidae) from Papua New Guinea

Six new species of the large lycaenid genus Philiris Röber, 1891 (Philiris petrieisp. n., Philiris bubalisatinasp. n., Philiris baitetasp. n., Philiris radicalasp. n., Philiris hindenburgensissp. n. and Philiris parsonsisp. n.), from Papua New Guinea, are described and illustrated, as are the early stages of the former taxon, with Litsea sp. near callophyllantha K. Schum (Lauraceae) recorded as the larval food plant. The holotypes of all but the latter are deposited in the ANIC, with that of P. parsonsi located in the BMNH. The external facies and male genitalia of all new species are compared in detail to putative known related species, and the types of these, in nearly all cases, are also illustrated.     

Papain protects papaya trees from herbivorous insects: role of cysteine proteases in latex

Many plants contain latex that exudes when leaves are damaged, and a number of proteins and enzymes have been found in it. The roles of those latex proteins and enzymes are as yet poorly understood. We found that papain, a cysteine protease in latex of the Papaya tree (Carica papaya, Caricaceae), is a crucial factor in the defense of the papaya tree against lepidopteran larvae such as oligophagous Samia ricini (Saturniidae) and two notorious polyphagous pests, Mamestra brassicae (Noctuidae) and Spodoptera litura (Noctuidae). Leaves of a number of laticiferous plants, including papaya and a wild fig, Ficus virgata (Moraceae), showed strong toxicity and growth inhibition against lepidopteran larvae, though no apparent toxic factors from these species have been reported. When the latex was washed off, the leaves of these lactiferous plants lost toxicity. Latexes of both papaya and the wild fig were rich in cysteine-protease activity. E-64, a cysteine protease-specific inhibitor, completely deprived the leaves of toxicity when painted on the surface of papaya and fig leaves. Cysteine proteases, such as papain, ficin, and bromelain, all showed toxicity. The results suggest that plant latex and the proteins in it, cysteine proteases in particular, provide plants with a general defense mechanism against herbivorous insects.     

The complete mitochondrial genome of Paracymoriza prodigalis (Leech, 1889) (Lepidoptera), with a preliminary phylogenetic analysis of Pyraloidea

The complete mitochondrial genome sequence is determined for Paracymoriza prodigalis (Leech, 1889). The 15,326 bp circular molecule possesses a gene organization and order identical to other sequenced Pyraloidea mitochondrial genomes. All tRNAs have the typical clover-leaf structure except for tRNA^Ser(AGN), which lacks the dihydrouridine (DHU) arm. The A+T-rich region of 343 bp includes the features common to the Lepidoptera, including the ‘ATAGA’ followed by an 19-bp poly-T stretch, but the tandem repeat sequences often appearing in available insects are not found. Phylogenetic relationships of eight subfamilies of 14 Pyraloidea species were constructed based on 13 PCGs of mitochondrial genomes using Bayesian inference (BI) and maximum likelihood (ML) methods. These phylogenies of the subfamilies within Pyraloidea accord well with morphological phylogenetic analysis except for the position of Schoenobiinae.     

Trichomes in Camptotheca acuminata Decaisne (Nyssaceae): Morphology,distribution, structure,and secretion

Camptotheca acuminata is a main source of the anti-cancer drug camptothecin (CPT). In this species, several studies have observed non-glandular trichomes (NGTs) and glandular trichomes (GTs). It has been assumed that GTs contain CPT, yet this has not been proven and no information is available on the accumulation of other secondary metabolites. The objective of this study was to describe the morphology, distribution and structure of C. acuminata trichomes and to investigate the chemical nature of the substances secreted by GTs. Light and fluorescence microscope, scanning electron microscope (SEM) and transmission electron microscope (TEM) were used to determine the morphology, distribution and structure of GTs and NGTs. Thin layer chromatography (TLC) and high-performance liquid chromatography (HPLC) analyses were carried out to confirm the presence of CPT in GTs, and histochemical tests were performed to investigate the presence of other secondary metabolites. C. acuminata possesses two types of GTs (GT1 and GT2), which differ in terms of their morphology, pattern of distribution and accumulated substances. The chemical analyses demonstrated that both GT1 and GT2 accumulate CPT. Histochemical analysis showed that phenols accumulate in the vacuole of GT2s. No isoprenoids were detected in GTs.     

Molecular detection of trophic links in a complex insect host-parasitoid food web

Previously, host-parasitoid links have been unveiled almost exclusively by time-intensive rearing, while molecular methods were used only in simple agricultural host-parasitoid systems in the form of species-specific primers. Here, we present a general method for the molecular detection of these links applied to a complex caterpillar-parasitoid food web from tropical rainforest of Papua New Guinea. We DNA barcoded hosts, parasitoids and their tissue remnants and matched the sequences to our extensive library of local species. We were thus able to match 87% of host sequences and 36% of parasitoid sequences to species and infer subfamily or family in almost all cases. Our analysis affirmed 93 hitherto unknown trophic links between 37 host species from a wide range of Lepidoptera families and 46 parasitoid species from Hymenoptera and Diptera by identifying DNA sequences for both the host and the parasitoid involved in the interaction. Molecular detection proved especially useful in cases where distinguishing host species in caterpillar stage was difficult morphologically, or when the caterpillar died during rearing. We have even detected a case of extreme parasitoid specialization in a pair of Choreutis species that do not differ in caterpillar morphology and ecology. Using the molecular approach outlined here leads to better understanding of parasitoid host specificity, opens new possibilities for rapid surveys of food web structure and allows inference of species associations not already anticipated.     

Fate of plant-derived secondary metabolites in three moth species (Syntomis mogadorensis,Syntomeida epilais,andCreatonotos transiens)

Summary Larvae of three moth species were compared with respect to strategies used to cope with secondary metabolites (allelochemicals) present in their diet.Syntomeida epilais is monophagous and accepted only oleander (which contains cardenolides, CG). CG were detected as stored products in the larvae and also in the faeces and exuviae. Pure CG (digoxin and gitoxin) which do not occur in oleander fed on oleander leaves were sequestered as the oleander CG.Syntomis mogadorensis is polyphagous: given a choice larvae avoided plants with a high load of allelochemicals. Upon shortage of preferred plants they ate a wide variety of plants which contain alkaloids, terpenes, or phenolics. Of these allelochemicals, alkaloids and CG were mainly recovered in the faeces and only minute fractions in the larvae.Creatonotos transiens larvae behaved similarly toSyntomis in terms of polyphagy and non-resorption. However, the larvae took up and stored pyrrolizidine alkaloids (PA) such as heliotrine selectively.Creatonotos is thus polyphagous (a generalist) but also a PA-specialist which exploits PA as defensive agents, as a morphogen for the male pheromone gland, and as a precursor for the male pheromone.Abbreviations CG cardiac glycosides - IG iridoid glycosides - PA pyrrolizidine alkaloids - GLC gas liquid chromatography - MS mass spectrometry     

A new species of Lesticus Dejean, 1828 (Coleoptera,Carabidae) from the Finisterre Range,Papua New Guinea and a key to the genera of pterostichine-like Harpalinae of New Guinea

Lesticus finisterrae (Carabidae: Pterostichini) sp. n. (type locality: Finisterre Range, Papua New Guinea), is described and characters to differentiate it from other “Trigonotomi” species are given. A key to the genera of pterostichine-like Harpalinae of the island, including all genera of Morionini, Cratocerini, Drimostomatini, Abacetini, Loxandrini and Pterostichini, is provided. The genus Rhytisternus (Pterostichini) is for the first time reported from New Guinea, represented by the likely adventive species Rhytisternus laevis (Macleay). The previously unknown male of Stegazopteryx ivimkaensis Will (Drimostomatini) is described.     

Contributions to the Cladocera fauna from Papua New Guinea

Twenty-eight taxa of the Cladocera are identified in collections from Papua New Guinea, 17 being new records for New Guinea, bringing the total number of Cladocera taxa reported for this region to 39. Most of the taxa are circumtropical. One species (Sarsilatona papuana) is endemic to Papua New Guinea and northern Australia. The species list includes two species that are normally listed as Holarctic:Alonella nana andAlona rustica. Widespread genera such asDaphnia, Pleuroxus, Disparalona, Acroperus were strikingly absent from the Papua New Guinean material.     

Purification and Characterization of Six Kiwifruit Proteases Isolated with Two Ion-exchange Resins,Toyopearl-SuperQ and Bakerbond WP-PEI

Kiwifruit (Actinidia chinensis) contains a cysteine protease, actinidin, and it was suggested to contain two components, A1 and A2. However, the separation of two components was not shown, and the comparison of the two components has not been thoroughly done.

We have now shown that actinidin can be separated into six proteases, named KP1, KP2, KP3, KP4, KP5, and KP6, by improved polyacrylamide gel electrophoresis at pH 4.0. Each kiwifruit protease was purified with two ion-exchange resins, Toyopearl-SuperQ and Bakerbond WP-PEI. Before the purification of kiwifruit proteases, excess p-chloromercuribenzoate was added to crude kiwifruit protease to prevent the autodigestion.

Each kiwifruit protease had a molecular mass of 23,500 and the same amino terminal sequences from the first to the thirteenth. They had different pI’s. These six kiwifruit proteases were divided into two groups by the effects of DTT and Zn²⁺ on the activity.

These results indicated that the six components must be A1, A2, and four previously unknown proteases. Thus we have separated the kiwifruit proteases which were thought to be two, into six components.