有机体之间化学相互作用的研究及其应用

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我国新担子菌类补遗

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洞庭湖滩血吸虫易感地带保水生态灭螺的试验研究

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云南省虫六新种（目：亚目）

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生态农业与乡村经济持续发展

生态农业与乡村经济持续发展张壬午,计文瑛,孙鸿良（天津农业部环境保护研究所,３００１９１）（中国农科院,北京１０００８１）ＥｃｏｌｏｇｉｃａｌＡｇｒｉｃｕｌｔｕｒｅａｎｄＳｕｓｔａｉｎａｂｌｅＤｅｖｅｌｏｐｍｅｎｔｏｆＲｕｒａｌＥｃｏｎｏｍｙ￥．ＺｈａｎｇＲｅｎｗｕ;ＪｉＷｅｎｙｉｎｇ（Ａｇｒｏ－ｅｎｖｉｒｏｎｍｅｎｔＰｒｏｔｅｃｌｉｏｎＩｎｓｔｉｔｕｔｅ,Ｔｉａｎｊｉｎ３００１９１）,ＳｕｎＨｏｎｇｌｉａｎｇ（ＣｈｉｎｅｓｅＡｃａｄｅｍｙｏｆＡｇｒｉｃｕｌｔｕｒａｌＳｃｉｅｎｃｃｓ,Ｂｅｉｊｉｎｇ１０００８１）．ＣｈｉｎｅｓｅＪｏｕｒｎａｌｏｆＥｃｏｌｏｇｙ,１９９３,１２（２）：１９—２０．ＴｈｉｓｐａｐｅｒｂｒｉｅｆｌｙｐｒｅｓｅｎｔｓｔｈｅｃｕｒｒｅｎｔｄｅｖｅｌｏｐｍｅｎｔｏｆｅｃｏｌｏｇｉｃａｌａｇｒｉｃｕｌｔｕｒｅｉｎＣｈｉｎａａｎｄｃｏｍｐａｒｅｓｗｉｔｈｔｈｅ＇＇ｓｕｓｔａｉｎａｂｌｅａｇｒｉｃｕｌｔｕｒｅａｎｄｒｕｒａｌｄｅｖｅｌｏｐｍｅｎｔ＇＇（ＳＡＲＤ）ｐｕｔｆｏｒｗａｒｄｂｙＦＡＯ,Ｃｈｉｎａ’ｓｓｕｓｔａｉｎａｂｌｅａ－ｇｒｉｃｕｌｔｕｒｅｉｓｎｏｔｏｎｌｙａｎｉｎｇｅｎｉｏｕｓ     

云衫针层孔菌化学成分的研究

从云衫针层孔菌Ｐｈｅｌｌｉｎｕｓ ｙａｍａｎｏｉ（Ｔａｍｚ．）ｓｈａｗ分离得到１２个化合物,借助光谱分析鉴定为：８,１１,１３－ａｂｉｅｔａｄｉｅｎ－１８－ｏｉｃ ａｃｉｄ（１）,１,２－ｂｅｎｚｅｎｅｄｉ－ｃａｒｂｏｘｙｌｉｃ ａｃｉｄｂｉｓ（２－ｅｔｈｙｌ－ｈｅｘｙｌ）ｅｓｔｅｒ（２）,ｅｒｇｏｓｔｅｒｏｌ ｐｅｒｏｘｉｄｅ（３）,ｅｒｇｏｓｔａ ７,２２（Ｅ）－ｉｄｅｎ－３－ｏｌ（４）,ｅｒｇｏｓｔａ ７,２２（Ｚ）－ｄｉｅｎ－３－ｏｌ（５）,ｏｃｔａｄｅｃａｎｏｉｃ ａｃｉｄ－１,３－ｐｒｏｐａｎｅｄｉｙｌ ｅｓｔｅｒ（６）,ｏｃｔａｄｅｃａｎｏｉｃ ａｃｉｄ（７）,８（１９）,１４－ｌａｂｄａｄｉｅｎ－１３－ｏｌ（８）,ｅｒｇｏｓｔａ－４,６,８（１４）,２２－ｔｅｔｒａｅｎ－３－ｏｎｅ（９）,化合     

部分裸子植物叶片总蛋白分析

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架棚中酚类化合物的研究

从架棚（ＣｅｒａｔｏｓｔｉｇｍａｍｉｎｕｓＳｔａｐｆｅｘＰｒａｉｎ）的乙酸乙酯部分分离得到１４个酚类化合物。经波谱技术,特别是２ＤＮＭＲ技术鉴定,其中化合物ｐｌｕｍｂｏｃａｔｅｃｈｉｎｓＡ（１）和Ｂ（２）为新化合物。其他１２个化合物被分别鉴定为ｐｌｕｍｂｏｌａｃｔｏｎｅＡ（３）、ｐｌｕｍｂａｂｉｃａｃｉｄ（４）、ｉｓｏｓｈｉｎａｎｏｌｏｎｅ（５）、ｅｐｉｓｏｓｈｉｎａｎｏｌｏｎｅ（６）、Ｎｔｒａｎｓｃａｆｅｏｙｌｔｙｒａｍｉｎｅ、Ｎｔｒａｎｓｆｅｒｕｌｏｙｌｔｙｒａｍｉｎｅ、ａｐｏｃｙｎｉｎ、ｖａｎｉｌｉｃａｃｉｄ、ｓｙｒｉｎｇｉｃａｃｉｄ、ｇａｌｏｃａｔｅｃｈｉｎ、（＋）ｃａｔｅｃｈｉｎ和１,２,６ｔｒｉＯｇａｌｏｙｌｇｌｕｃｏｓｅ。     

宽阔水自然保护区的虫草及其相关真菌I.

本文报道采用贵州省宽阔水自然保护区的９种虫草,它们是多壳虫草新咱（ＣｏｒｄｙｃｅｐｓｐｏｌｙｃａｒｐｉｃａＬｉａｎｇ＆Ｌｉｕｓｐ．ｎｏｖ）,鼠尾虫草新种（ＣｏｒｄｙｃｅｐｓｍｕｓｉｃａｕｄａｔａＬｉａｎｇｅｔＬｉｕｓｐ．ｎｏｖ）针孢虫草（ＣｏｒｄｙｃｅｐｓａｃｉｃｕｌａｒｉｓＲｅｖ．ｅｘＢｅｒｋ．）罗伯茨虫草（Ｃｏｒｄｙｃｅｐｓｒｏｂｅｒｔｓｉｉ（Ｈｏｏｋ）,Ｇｒａｙ）下垂虫草（Ｃｏｒｄｙｃｅｐｓ     

银叶老鹳草(Geranium sylvaticum)种群中诱导保护抗性和病原菌相互作用的研究（英）

本文通过自然植物种群接种实验,人工接种实验和野外调查研究了（Geranium sylvaticum)对老鹳草单孢锈菌（Uromyces geranii)（长生活史）的抗病性在受柄锈菌（Puccinia)（短生活史）感病前后和受2种柄锈菌（P.leveillei或P.morthieri)感病后有无区别,以及在同一季节里感染同一寄主植物的长生活史单孢锈菌和短生活史柄锈菌间的相互作用,病原菌间的相互作用使寄主植物产生诱导保护抗性。结果表明,P.leveillei可诱导寄主植物产生短时间的保护抗性,而P.morthieri可能诱导寄主植物产生长时期的保护抗性,诱导保护抗性可能是影响自然植物种群中植病式样的重要因素之一。     

Interaction Between Puccinia xanthii and Facultative Parasitic Fungi on Xanthium occidentale

The present study was undertaken to evaluate the possible interactions between Puccinia xanthii and facultative parasitic fungi isolated from plants of the Noogoora burr complex. Six different Colletotrichum spp., a Phomopsis sp. and Alternaria zinniae, the latter a potential bioherbicide for Xanthium weeds, were tested. Alternaria zinniae caused necrotic lesions of leaf and stem on healthy and rust-infected Noogoora burr plants and did not specifically infect rust lesions. Most Colletotrichum spp. infected Noogoora burr via leaf and stem rust lesions. The infected lesions of P. xanthii became necrotic and the pustules did not reach maturity. Colletotrichum orbiculare was the only facultative parasite able to grow beyond the rust lesions into the surrounding tissue, girdle the stem, and consequently kill the plant tissue above. Colletotrichurn orbiculare did not infect plants previously infected by A. zinniae. The possible additive or synergistic adverse effects of the rust and the facultative parasitic fungi on the Noogoora burr complex offer new avenues to explore for biological control.     

An investigation into the involvement of defense signaling pathways in components of the nonhost resistance of Arabidopsis thaliana to rust fungi also reveals a model system for studying rust fungal compatibility

Seventeen accessions of Arabidopsis thaliana inoculated with the cowpea rust fungus Uromyces vignae exhibited a variety of expressions of nonhost resistance, although infection hypha growth typically ceased before the formation of the first haustorium, except in Ws-0. Compared with wild-type plants, there was no increased fungal growth in ndr1 or eds1 mutants defective in two of the signal cascades regulated by the major class of Arabidopsis host resistance genes. However, in the Col-0 background, infection hyphae of U. vignae and two other rust fungi were longer in sid2 mutants defective in an enzyme that synthesizes salicylic acid (SA), in npr1 mutants deficient in a regulator of the expression of SA-dependent pathogenesis related (PR) genes, and in NahG plants containing a bacterial salicylate hydroxylase. Infection hyphae of U. vignae and U. appendiculatus but not of Puccinia helianthi were also longer in jar1 mutants, which are defective in the jasmonic acid defense signaling pathway. Nevertheless, haustorium formation increased only for the Uromyces spp. and only in sid2 mutants or NahG plants. Rather than the hypersensitive cell death that usually accompanies haustorium formation in nonhost plants, Arabidopsis typically encased haustoria in calloselike material. Growing fungal colonies of both Uromyces spp., indicative of a successful biotrophic relationship between plant and fungus, formed in NahG plants, but only U. vignae formed growing colonies in the sid2 mutants and cycloheximide-treated wild-type plants. Growing colonies did not develop in NahG tobacco or tomato plants. These data suggest that nonhost resistance of Arabidopsis to rust fungi primarily involves the restriction of infection hypha growth as a result of defense gene expression. However, there is a subsequent involvement of SA but not SA-dependent PR genes in preventing the Uromyces spp. from forming the first haustorium and establishing a sufficient biotrophic relationship to support further fungal growth. The U. vignae-Arabidopsis combination could allow the application of the powerful genetic capabilities of this model plant to the study of compatibility as well as nonhost resistance to rust fungi.     

New, rare and remarkable records of microfungi from the Slovakian Republic

During an excursion to the Slovakian Republic (lower and upper Tatra) of the Botanical Institute of the University of Essen in 2004 we were able to collect about 150 species of microfungi as parasites or saprophytes on cultivated crops and wild plants. Some of them are new for the entire world and a few of them are new for the Slovakian Republic, e.g: Ramularia liliicola N. Ale-Agha, U. Braun & G.B. Feige on Lilium martagon L.; Septoria aegopodii DESM. Ex Kickx. F. on Aegopodium podagaria L.; Puccinia asarina Kunze on Asarum europaeum L.; Puccinia polygoni ALB. & SCHW. and Puccinia polygoni-amphibii PERS. on Bilderdykia convolvulus (L.) Du Mont.; Ramularia chamaenerii Rostr. and Mycosphaerella chamaenerii Saville on Epilobium angustifolium L.; Plasmopara pusilla (de By.) Schroet on Geranium sylvaticum L.; Cercosporidium depressum (Berk. & Br.) Deighta on Angelica sylvestris L. All specimens are located in the Herbarium ESS, Mycotheca Parva collection G.B. Feige & N. Ale-Agha.     

Morphological and molecular characterisation of Puccinia lagenophorae, now present in central North America

In June 2004, a rust fungus not previously reported for Oklahoma was found occurring naturally on the weed, common groundsel, Senecio vulgaris, in pots in a commercial container nursery in northeastern Oklahoma. Host symptoms and morphology of teliospores and aeciospores of the fungus were consistent with those of Puccinia lagenophorae, a recent introduction into North America that has, as yet, been reported only on the East and West Coasts of the USA. This is the first report of the rust in central regions of North America. The rust is believed to be native to Australia and New Zealand and subsequently reported in most continents on numerous species and genera of the Asteraceae. Some authors in Europe consider the rust on Bellis as different from the one on Senecio, naming it Puccinia distincta. Our ITS1‐5.8S‐ITS2 ribosomal DNA sequence data, however, show homology with P. distincta sequences from Europe, indicating there is only one morphologically‐variable polyphagous species. Presumably, the rust was introduced into Oklahoma on infected plants from the West Coast of the USA, the source of most plant material in the commercial nursery where it was found. The rust is potentially important on several ornamental Asteraceae in North America as it has become in Europe, where it spreads rapidly throughout that continent following its introduction there in the early 1960s.     

The Effects of Temperature on the Respiratory Responses of Groundsel (Senecio vulgaris) to Infection by Rust (Puccinia lagenophorae)

Groundsel (Senecio vulgaris) was grown in either a warm (20°C) or a cool (8°C) controlled environment and infected with Puccinia lagenophorae. Dark respiration, measured over the range 6 to 18°C, was higher in leaves of healthy plants grown under low temperatures than in those of plants grown under high temperatures. Infection increased the rates of dark respiration in the region of sporulating lesions in both sets of plants, but the greater increase in plants grown under warm conditions resulted in both sets having similar respiration rates across the range 6 to 18°C. The conclusion that the magnitude of the respiratory increase following rust infection depends upon the conditions under which plants were grown is supported by literature on other rust diseases and has implications for the utilization of carbohydrate reserves and the survival of both rust and host populations over winter.     

Accumulation of genes for susceptibility to rust fungi for which barley is nearly a nonhost results in two barley lines with extreme multiple susceptibility

Nonhost resistance is the most common type of resistance in plants. Understanding the factors that make plants susceptible or resistant may help to achieve durably effective resistance in crop plants. Screening of 109 barley (Hordeum vulgare L.) accessions in the seedling stage indicated that barley is a complete nonhost to most of the heterologous rust fungi studied, while it showed an intermediate status with respect to Puccinia triticina, P. hordei-murini, P. hordei-secalini, P. graminis f. sp. lolii and P. coronata ff. spp. avenae and holci. Accessions that were susceptible to a heterologous rust in the seedling stage were much more or completely resistant at adult plant stage. Differential interaction between barley accessions and heterologous rust fungi was found, suggesting the existence of rust-species-specific resistance. In particular, many landrace accessions from Ethiopia and Asia, and naked-seeded accessions, tended to be susceptible to several heterologous rusts, suggesting that some resistance genes in barley are effective against more than one heterologous rust fungal species. Some barley accessions had race-specific resistance against P. hordei-murini. We accumulated genes for susceptibility to P. triticina and P. hordei-murini in two genotypes called SusPtrit and SusPmur, respectively. In the seedling stage, these accessions were as susceptible as the host species to the target rusts. They also showed unusual susceptibility to other heterologous rusts. These two lines are a valuable asset to further experimental work on the genetics of resistance to heterologous rust fungi.Electronic Supplementary Material Supplementary material is available in the online version of this article at http://dx.doi.org/10.1007/s00425-004-1319-1Abbreviations ff. spp Formae speciales - RIL Recombinant inbred line - DC Double cross - DC-S Progeny produced by selfing of double-cross plants     

The mixed mating system of Impatiens capensis and infection by a foliar rust pathogen: patterns of resistance and fitness consequences

Outcrossing by hosts may offer protection from natural enemies adapted to parental genotypes by creating diverse progeny that differ from their parents through genetic recombination. However, past experimental work addressing the relationship between mating system and disease in offspring has given conflicting results, suggesting that outcrossing might also cause the dissolution of resistant genotypes. To determine if selfed progeny are more susceptible to disease caused by the heteroecious rust, Puccinia recondita, or if selfing preserves existing resistant genotypes, we used a factorial design to compare levels of infection of selfed and outcrossed progeny of Impatiens capensis, a woodland annual with a mixed mating system. We compared the level of host infection when exposed to three pathogen sources in the field: the sympatric rust population, and two allopatric rust populations. Outcrossed progeny exposed to sympatric rust had higher infection scores than selfed progeny exposed to the same rust, suggesting that outcrossing breaks up resistant genotypes. In addition, there was a trend for the rust to be more infective on sympatric rather than allopatric hosts. We also examined whether rust infection differentially alters the fitness of selfed and outcrossed progeny. Outcrossed plants that escaped infection had higher fitness, as measured by fruit production, than selfed plants, but there was no difference in fitness between infected selfed and infected outcrossed plants. Thus, outcrossing was advantageous in the absence of disease, but there was no fitness difference between selfed and outcrossed progeny in the presence of disease. In sum, our results indicate that interactions with pathogens can eliminate or reverse the advantage of outcrossing.     

High diversity of genes for nonhost resistance of barley to heterologous rust fungi

Inheritance studies on the nonhost resistance of plants would normally require interspecific crosses that suffer from sterility and abnormal segregation. Therefore, we developed the barley-Puccinia rust model system to study, using forward genetics, the specificity, number, and diversity of genes involved in nonhost resistance. We developed two mapping populations by crossing the line SusPtrit, with exceptional susceptibility to heterologous rust species, with the immune barley cultivars Vada and Cebada Capa. These two mapping populations along with the Oregon Wolfe Barley population, which showed unexpected segregation for resistance to heterologous rusts, were phenotyped with four heterologous rust fungal species. Positions of QTL conferring nonhost resistance in the three mapping populations were compared using an integrated consensus map. The results confirmed that nonhost resistance in barley to heterologous rust species is controlled by QTL with different and overlapping specificities and by an occasional contribution of an R-gene for hypersensitivity. In each population, different sets of loci were implicated in resistance. Few genes were common between the populations, suggesting a high diversity of genes conferring nonhost resistance to heterologous pathogens. These loci were significantly associated with QTL for partial resistance to the pathogen Puccinia hordei and with defense-related genes.     

Competition in mixtures of susceptible and resistant genotypes of Chondrilla juncea differentially infected with rust

Plants of two genotypes of Chondrilla juncea (skeleton weed), one susceptible to and the other resistant to one isolate of the rust Puccinia chondrillina, were grown as pure and mixed populations both in the presence and absence of rust. Weights of individual plants were obtained at two harvests, one when the plants were rosettes and the other when flowering had begun. Distributions of plant weights of each genotype became progressively more positively skewed with time, with rust infection of plants of the susceptible genotype and with increasing competition between plants of both genotypes. The results show that genetic differences may be an important factor in determining which individuals become dominant or are suppressed in competing mixtures, and that differential disease pressure may alter dominance of individuals in plant populations.