煤污病菌表皮生态位适应性进化机制研究进展

煤污病是一类外寄生性植物真菌病害。煤污病菌在果实表面形成黑色污斑和污点,导致外观品质降低影响销售,给果农造成严重经济损失。真菌的适应性进化分子机制一直是植物病原真菌生态学领域的研究前沿。煤污病菌在进化过程中为适应寄主表面营养贫瘠、干旱、紫外线照射等非生物胁迫,以及与表面其他微生物竞争生物胁迫等极端环境,进化出一系列独特机制,从而成功定殖于植物表皮。本文从基因组结构趋同进化、致病相关基因家族收缩与扩张和胁迫响应等方面,系统综述了煤污菌群对表皮生态位的适应性进化分子机制。     

柑橘煤污病病原菌的研究

采用病菌标本直接观察和人工培养物观察两种方法对贵州柑橘煤污病病原菌进行了鉴定。结果表明,柑橘煤污病的优势病原菌为Chaetothyrium spinigerum、Triposporiopsis spinigera、Fumago vagans、Cladosporium cladosporioides、Alternaria tenuissima和A.alternate6种。     

中国叶围煤污菌初探——Ⅲ.黄瓜叶围煤污菌的研究

对山东省黄瓜(Cucumis sativus L.)叶围煤污菌种群组成、分布、演替和对黄瓜的生理影响的研究结果表明;8个地市黄瓜叶面真菌有15属21种,其中属煤污菌的有6属10种:链格孢(Alternaria alternata Karst.),出芽短梗霉[Aureobasidium pullulans(deBary)Arn.],芽枝状枝孢[Cladosporium cladosporioides(Fres.)de Vries]尖孢枝孢(C.oxysporum Berk.＆Curt.)大孢枝孢(C.macarocarpum Preuss),多主枝孢[C.herbarum(Pers.)Link.],球孢枝孢(C.sphaerospermum Perz.),灰腐质霉(Humicola grisea Traaen.),紫附球菌(Epicoccum purpurascens Ehrenb.ex Wallr.)和弯孢霉[Curvularia lunala (Walk.)Boed.].链格孢和枝孢霉(Cladosporium spp.)是各地区主要种群.黄瓜叶面真菌的种类和密度与苗龄、叶面可溶性糖和氨基酸组分含量成极显著正相关.随着苗龄的增长,真菌的密度和种类增多.用两个主要种群的分生孢子悬浮液接种黄瓜叶面,形成明显的煤污,导致叶面光合作用降低,呼吸作用升高,气孔阻力增大,蒸腾作用下降.穗状德氏霉(Drechsleraspicifer R.Nelson)和核茎点霉(Phoma pulaminum Speg.)是国内的新记录.     

中国叶围煤污菌初探II．毛白杨叶围煤污菌的研究

对毛白杨(Populus tomentosa Carr.)叶围煤污菌(sooty moulds)群落组成及演替进行了探罚,分析了叶面营养物及其变化。 结果表明,叶面真菌的分离物密度随叶片的衰老而增加。对毛白杨叶面真菌分离鉴定,属于煤污菌有8种真菌：链格孢(Alternaria alternata),芽枝状枝孢(Cladosporium cladosporioides),球孢枝孢(Coladosporium sphaerospermum),尖孢枝孢(Cladosporium oxysporum),出芽短梗霉(Aurecobasidium pullulans),棕黑腐质霉(Humtco'a tuscoatra),伏克盾壳霉(Coniothyrixm fuckelii)和直立枝顶孢(Acremoniumstrictum)。不同生长期叶面真菌群落组成及优势种不同,叶面出现黑霉层后,以3种煤污菌为优势种即出芽短梗霉、链格孢和芽枝状枝孢。不同的菌表现一定的演替模式,定殖及达到峰值的时间不同。毛白杨叶面含有多种营养物,其含量及组分随生长期不同而异．与叶面真菌分离物密度呈显著性相关。此外,对蚜虫的发生、叶面营养物含量、煤污菌三者的关系进行了讨论。     

中国叶围煤污菌初探——Ⅲ.黄瓜叶围煤污菌的研究

对山东省黄瓜(Cucumis sativus L.)叶围煤污菌种群组成、分布、演替和对黄瓜的生理影响的研究结果表明;8个地市黄瓜叶面真菌有15属21种,其中属煤污菌的有6属10种:链格孢(Alternaria alternata Karst.),出芽短梗霉[Aureobasidium pullulans(deBary)Arn.],芽枝状枝孢[Cladosporium cladosporioides(Fres.)de Vries]尖孢枝孢(C.oxysporum Berk.＆Curt.)大孢枝孢(C.macarocarpum Preuss),多主枝孢[C.herbarum(Pers.)Link.],球孢枝孢(C.sphaerospermum Perz.),灰腐质霉(Humicola grisea Traaen.),紫附球菌(Epicoccum purpurascens Ehrenb.ex Wallr.)和弯孢霉[Curvularia lunala (Walk.)Boed.].链格孢和枝孢霉(Cladosporium spp.)是各地区主要种群.黄瓜叶面真菌的种类和密度与苗龄、叶面可溶性糖和氨基酸组分含量成极显著…     

煤绒菌原质团和菌核甲醇提取物抗氧化活性的研究

为探索黏菌的抗氧化活性,以总还原力、DPPH自由基清除率及O2自由基清除率为指标,首次对煤绒菌原质团和菌核甲醇提取物进行抗氧化活性研究。结果表明:煤绒菌原质团和菌核甲醇提取物均有较好的抗氧化活性,当质量浓度为0.8 mg/mL时,二者对O2自由基的清除能力最强,清除率分别为70.39%和86.83%;当质量浓度为0.4 mg/mL时,二者对DPPH自由基的清除能力最强,清除率分别为57.22%和62.91%,通过比较IC50值,菌核粗提物的抗氧化能力略优于原质团。     

稻瘟病菌侵入机理

猪瘟病广泛分布于水稻栽培的国家和地区,几乎每年都可以调查到该病发生,给生产造成严重损失。研究稻瘟病菌与水稻之间相互作用,特别是近年来开展猪瘟病菌致病的分于生物学研究成了一个热点。1病害循环（1）病菌分生抱于尖端的粘胶和孢子发芽使得孢子粘着在寄主表面;（2）芽     

林下参内生球毛壳菌FS-01对人参病原真菌的抑制作用

为探究林下参内生真菌球毛壳菌(Chaetomium globosum)FS-01菌株对人参病原菌的抑菌作用,该研究在实验室条件下,测定了FS-01菌株菌丝、发酵液和孢子悬浮液对人参黑斑病菌(Alternaria panax)、人参菌核病菌(Sclerotinia schinseng)、人参灰霉病菌(Botrytis cinerea)、人参立枯病菌(Rhizoctonia solani)、人参根腐病菌(Fusarium solani)5种人参病原菌的抑制作用。结果表明:内生真菌球毛壳菌FS-01对5种病原菌均有抑制作用,其中,对人参黑斑病菌的抑制作用最高,为30.80%,其次是人参立枯病菌、人参菌核病菌、人参根腐病菌和人参灰霉病菌; 发酵液抑菌实验结果表明,在加入内生真菌球毛壳菌FS-01菌株发酵液的PDA培养基上,对人参灰霉病菌的抑制作用最高,为82.09%,其次是人参菌核病菌、人参黑斑病菌、人参立枯病菌和人参根腐病菌; 孢子抑菌实验结果表明,在加入内生真菌球毛壳菌FS-01菌株孢子悬浮液的PDA培养基上,对人参黑斑病菌的抑制作用最高,为83.72%,其次是人参灰霉病菌、人参立枯病菌、人参菌核病菌和人参根腐病菌。综上结果认为,内生真菌球毛壳菌FS-01菌株对人参病原菌均有很高的抑菌作用,可作为人参病原菌的生防菌株资源。     

抗菌蛋白产生菌TG26的筛选及其培养条件

从丝瓜(Luffa cylindrica(L.)Roem.)根部分离纯化并筛选出强烈抑制小麦赤霉病菌(Gibberella zeae)生长、产大量抗菌蛋白的芽孢杆菌(Bacillus spp.)TG26菌株。用异步培养法检测了该菌株的抗菌活性,比对照菌株 B.subtilis A014和 B_(?)的活性强;平板扩散法测定的 TG26抗菌谱表明,该菌株除抑制小麦赤霉病菌外,对烟草赤星病菌(Alternaria longipes)、棉花枯萎病菌(F.oxysporum f.vasinfectum)、西瓜枯萎病菌(F.oxysporum f.niveum)和绿色木霉(Trichoderma viride)等植物病原真菌以及烟草青枯病菌(Psendomonassolanaceanum)和水稻白叶枯病菌(Xanthomonas campestris pv.oryzae)等植物病原细菌均表现出很强的拮抗作用。TG26菌株产抗菌蛋白的最适培养条件为:选用 BPY 液体培养基,起始 pH7.0。接种后30℃振荡培养36小时的培养液经70%饱合度(NH_4)_2SO_4盐析得到130 mg/L 以上的粗蛋白。该蛋白对温度不敏感,对蛋白酶 K 部分敏感。     

油茶主要病虫害生态空间分布规律的研究

应用生态空间分布的分析方法,研究了油茶主要病虫害的空间分布规律。结果表明软腐病、炭疽病、油茶毒蛾为均匀分布;煤污病、白绢病,茶梢蛾为随机分布;茶蚕为聚集分布。     

Recent advances in the study of Kaposi's sarcoma-associated herpesvirus replication and pathogenesis

It has now been over twenty years since a novel herpesviral genome was identified in Kaposi's sarcoma biopsies. Since then, the cumulative research effort by molecular biologists, virologists, clinicians, and epidemiologists alike has led to the extensive characterization of this tumor virus, Kaposi's sarcoma-associated herpesvirus(KSHV; also known as human herpesvirus 8(HHV-8)), and its associated diseases. Here we review the current knowledge of KSHV biology and pathogenesis, with a particular emphasis on new and exciting advances in the field of epigenetics. We also discuss the development and practicality of various cell culture and animal model systems to study KSHV replication and pathogenesis.     

The structure, reproduction and taxonomy of Vidalia and Osmundaria (Rhodophyta, Rhodomelaceae)

Comprises species occurring mostly in subtidal habitats in tropical, subtropical and warm-temperate areas of the world. An analysis of the type species, V. spiralis (Sonder) Lamouroux ex J. Agardh, a species from Australia, establishes basic characters for distinguishing species in the genus. These characters are (1) branching patterns of thalli, (2) flat blades that may be spiralled on their axis, (3) width of the blade, (4) primary or secondary derivation of sterile and fertile branchlets and (5) position of sterile and fertile branchlets on the thalli. Application of the latter two characters provides an important basic method for separation of species into three major groups. Osmundaria , a genus known only in southern Australia, was studied in relation to Vidalia , and its separation from the Vidalia assemblage is not accepted. Species of Vidalia therefore are transferred to the older genus name, Osmundaria. Two new species, Osmundaria papenfussii and Osmundaria oliveae are described from Natal. Confusion in the usage of the epithet, Vidalia fimbriala Brown ex Turner has been clarified, and Vidalia gregaria Falkenberg, described as an epiphyte on Osmundaria pro/ifera Lamouroux, is revealed to be young branches of the host, Osmundaria prolifera.     

New or rare chromosome counts in Artemisia L. (Asteraceae, Anthemideae) and related genera from Kazakhstan

Fifteen chromosome counts of six Artemisia taxa and one species of each of the genera Brachanthemum, Hippolytia, Kaschgaria, Lepidolopsis and Turaniphytum are reported from Kazakhstan. Three of them are new reports, two are not consistent with previous counts and the remainder are confirmations of very scarce (one to four) earlier records. All the populations studied have the same basic chromosome number, x = 9, with ploidy levels ranging from 2x to 6x. Some correlations between ploidy level, morphological characters and distribution are noted.     

肝癌中HBV和HCV基因和抗原的分布及意义

采用原位分子杂交方法检测HCV RNA及HBV X基因;采用免疫组织化学方法研究HCV核心抗原,非结构区C33c抗原及HBxAg在肝细胞肝癌中的定位及分布.结果表明(1)HCV RNA、HBV X基因在肝细胞肝癌组织检出率分别为40%(55/136)和82%(112/136).HCV RNA定位于癌细胞的胞浆内,阳性细胞呈散在、灶状及弥漫分布三种形式;HBV X基因在肝癌细胞中的分布呈胞浆型、核型及核浆型,阳性细胞也呈上述三种分布形式;(2)HCV C33c抗原、核心抗原在肝细胞肝癌中的阳性率为81%(133/164)及86%(141/164).C33c抗原定位于癌细胞及肝细胞的胞浆内;核心抗原既定位于癌细胞核中,又可定位于胞浆中.C33c抗原阳性细胞以灶状分布为主;而核心抗原阳性细     

Selection with two alleles and complete dominance

For a plant selection model with frequency-independent viabilities, fertilities and selfing rates, it is shown that apart from global fixation, for certain parameter combinations a protected polymorphism and facultative fixation (either allele may become fixed according to initial frequencies) may both occur. Facultative fixation requires different selling rates for the dominant and recessive type. Protection of the polymorphism requires resource allocation for male and female function. In this connection the problem of purely genetically caused population extinction is discussed.
For general frequency dependence and regular segregation, the chances for establishment of a completely recessive gene are compared to those of a completely dominant gene. It is proven that the process of establishment of the recessive gene, despite a fitness advantage, may be considerably endangered by drift effects if random mating prevails. The recessive gene may reach the same effectivity in establishment as a dominant gene, only if the recessive homozygote mates exclusively with its own type during the period of establishment.