分离自苇状羊茅(Festuca arundinacea Schreb.)的内生真菌Neotyphodium uncinatum

从苇状羊茅植株中发现了与Neotyphodium coenophialum不同的内生真菌,经过分离、培养,分离菌株被鉴定为Ne-otyphodium uncinatum(W.Gams,Petrini&D.Schmidt)Glenn,Bacon & Hanlin.通过对苇状羊茅植株各部位的调查,确认该菌在植株的地上部分有较为系统的分布.所发现的Neotyphodium uncinatum-Festuca arundinacea这一内生真菌-宿主植物的新组合将成为禾本科植物内生真菌研究的宝贵材料.     

Effects of Neotyphodium endophytes on growth, reproduction and drought-stress tolerance of three Lolium perenne L. genotypes

Three Lolium perenne L. genotypes collected from different natural habitats were tested for the effects of their fungal endophyte Neotyphodium spp. on plant growth and seed yield. Half the clones of the originally infected plants were subjected to fungicide treatment to eradicate the endophytes. In an experiment, the clones were planted separately into pots and were either watered adequately or subjected to drought stress. In the genotype collected from a dry site, the endophyte infection reduced plant growth at an adequate water supply, but increased regrowth under drought. In the genotype from a periodically either flooded or dry site, endophyte infection significantly promoted the development of reproductive tillers and seed production (effects which are associated with adaptation to drought). In contrast, the genotype that originated from a wet site showed higher sensitivity to drought stress when endophyte infection was present. The results suggest that environmental conditions in the original habitat of the plants may influence the symbiotic interaction between plant and fungus, probably through natural selection. However, endophyte‐induced increases in root dry weight and root/shoot ratio were recorded for all three genotypes. These features could be beneficial for plant persistence, especially on sites where water is the growth‐limiting factor.     

Fungal endophytes in grasses from semi-arid permanent grasslands of western Spain

Abstract A survey of grass species associated with Epichloë and Neotyphodium fungal endophytes was made in permanent semi‐arid grasslands of western Spain. Endophytes were isolated from 11 of 49 grass species analysed. Infected plants of Festuca arundinacea, Festuca rubra, Dactylis glomerata and Lolium perenne were detected at most locations studied. The grasses, Agrostis castellana, Brachypodium phoenicoides and Festuca ampla, are previously unknown endophyte hosts. The results obtained show that endophyte–grass interactions are present in the grasslands where this study was conducted.     

The evaluation of endophyte toxin residues in sheep fat

Abstract

AIM: To monitor changes in concentrations of lolitrem B and epoxy-janthitrems in the fat of sheep grazing perennial ryegrass infected with wild-type- and AR37-endophyte, respectively, during the time of year when ryegrass staggers would be expected to be observed.

METHODS: Ten 5-month-old lambs with no previous exposure to endophytes were grazed on either wild-type (containing lolitrem B, n = 5) or AR37 (containing epoxy-janthitrems, n = 5) endophyte-infected perennial ryegrass (Lolium perenne L.) pastures between October 2008 and June 2009. Animals were regularly assessed for ryegrass staggers using the Keogh scale (0 = no signs, 5 = severe tremors). When a score of > 3.5 was observed animals were removed from the treatment pastures for 1 month. Fat biopsy samples were taken from each animal at approximately monthly intervals and analysed for endophyte metabolites using high performance liquid chromatography (HPLC) methods developed during this study. Regular herbage samples were also taken and concentrations of endophyte metabolites measured.

RESULTS: Efficient and reproducible methods to analyse both lolitrem B and epoxy-janthitrems in fat were developed. Concentrations of lolitrem B and epoxy-janthitrems in herbage and in sheep fat increased from late November to peak in mid-February. Ryegrass staggers was observed in both groups of sheep at this time. Following 1 month of grazing non-infected pasture mean concentrations in fat of lolitrem B decreased by 43% from 61.8 to 35.3 ppb, and of epoxy-janthitrems by 38% from 1032.0 to 639.5 ppb. Maximum concentrations in herbage of epoxy-janthitrems (35.7 ppm) were higher than of lolitrem B (3.4 ppm), but signs of staggers were less severe in sheep grazing pasture containing the former compared with the latter (median Keogh scores in late February were 2 and 3, respectively), consistent with epoxy-janthitrems being low potency toxins.

CONCLUSION: This study demonstrated that concentrations of epoxy-janthitrems and lolitrem B in sheep fat increased quickly during the initial phase of the study when concentrations in pasture increased, and decreased when animals were removed from pastures containing these compounds. These data will be used in the risk assessment of the endophyte metabolites.     

2007—2012年蚌埠地区主要白蚁种类变化调查

白蚁对农林作物、房屋建筑、家具、水库、江河堤坝、国防用品、电缆等均有不同程度的危害。对蚌埠地区白蚁发生情况进行调查,结果表明:目前蚌埠地区有8种白蚁危害,隶属2科3属。分别是散白蚁属圆唇散白蚁、黑胸散白蚁、拟尖唇散白蚁、肖若散白蚁、弯颚散白蚁;土白蚁属黑翅土白蚁、囟土白蚁;乳白蚁属上海乳白蚁。其中,圆唇散白蚁、黑胸散白蚁在蚌埠及市辖3县(怀远县、固镇县、五河县)各地区内均有分布,为蚌埠地区白蚁优势种,肖若散白蚁分布于怀远县找郢乡及附近地区,是近几年新发现种;黑翅土白蚁、囟土白蚁分布于怀远县大洪山及蚌埠市郊各山林内;上海乳白蚁为2010年蚌埠某企业从广东顺德通过木质包装箱带入。通过对蚌埠市2007—2011年的白蚁出飞记录统计,发现蚌埠市白蚁出飞上报户数由2007年最多的91户降至2009年最少的49户,后2010年反弹至79户。白蚁危害最为严重的多在木门框、木窗和门套处。随着近2年家庭装修趋于豪华高档,木质材料使用增多,为白蚁提供了良好的食材,创造了白蚁易滋生的环境。针对2012年白蚁出飞情况调查,所有的出飞点都在淮河以南,并主要集中于龙子湖区和蚌山区。蚌埠地区白蚁防治工作任重道远。     

Genetic differentiation between hosts and locations in populations of latent Botrytis cinerea in southern England

This study tested the hypothesis that aggressive, localized infections and asymptomatic systemic infections were caused by distinct specialized groups of Botrytis cinerea, using microsatellite genotypes at nine loci of 243 isolates of B. cinerea obtained from four hosts (strawberry (Fragaria×ananassa), blackberry (Rubus fruticosus agg.), dandelion, (Taraxacum officinale agg.) and primrose (Primula vulgaris)) in three regions in southern England (in the vicinities of Brighton, Reading and Bath). The populations were extremely variable, with up to 20 alleles per locus and high genic diversity. Each host in each region had a population of B. cinerea with distinctive genetic features, and there were also consistent host and regional distinctions. The B. cinerea population from strawberry was distinguished from that on other hosts, including blackberry, most notably by a common 154‐bp amplicon at locus 5 (present in 35 of 77 samples) that was rare in isolates from other hosts (9/166), and by the rarity (3/77) of a 112‐bp allele at locus 7 that was common (58/166) in isolates from other hosts. There was significant linkage disequilibrium overall within the B. cinerea populations on blackberry and strawberry, but with quite different patterns of association among isolates from the two hosts. No evidence was found for differentiation between populations of B. cinerea from systemically infected hosts and those from locally infected fruits.     

黑核桃内生真菌HJ1油脂提取工艺的研究

以黑核桃内生真菌HJ1菌体为材料,研究了提取温度、提取时间和料液比对菌体油脂得率的影响。经单因素试验、正交试验及验证试验,结果表明:HJ1油脂得率为22.26%左右,最佳提取工艺条件为:提取温度85℃,提取时间4 h,料液比1∶6。HJ1油脂组成与植物油脂组成相似,可作为制备生物柴油的原料。     

碳汇林业—兼论山东省碳汇造林

对碳汇林业的背景、相关概念、碳汇造林国内外现状、CDM造林再造林项目运行程序及设计书内容、造林再造林碳汇项目涉及的几个技术问题进行了综述,建议:山东具有碳汇造林的条件、积极争取碳汇造林项目、强化农用林和经济林的碳汇作用、加强干瘠山地、盐碱地及沿海防护林碳汇造林、加强中幼林的可持续经营管理、加紧实施山东森林碳汇储量与潜力研究、科学研究、人才培养及技术培训等。     

银杏内生真菌的分离及其抑菌活性初探

从银杏的茎和根中分离得到32株内生真菌,并对其发酵液和菌丝丙酮提取物的抑菌活性进行了测定。结果表明:筛选出1株对4种供试菌均有强烈抑菌作用的菌株,命名为L25菌株,其抑菌活性成分在90℃以下和对紫外线稳定。     

川渝油气田建设水土流失影响因子分析

以川渝地区油气田管线建设区域为主要研究对象,确定了9条代表性输气管线工程,选取其中4条不同工程类型管线,现场设定24个典型监测点位,实地监测实际发生的水土流失量;利用通用方程USLE对水土流失量进行预测;运用SPSS软件对监测结果和预测结果进行拟合,同时对USLE中5个显著影响因子进行扰动性矩阵分析。结果表明:（1）USLE在川渝地区油气田建设过程中预测水土流失量与实际水土流失量的拟合效果较好,适用于研究区。（2）水土流失主要影响因子影响程度优先度排序为:土壤可蚀性因子 > 植物覆盖因子 > 降雨侵蚀因子 > 土壤保持措施因子 > 坡度因子。