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1.
云南虫生真菌粉棒束孢遗传分化研究   总被引:3,自引:2,他引:1  
对云南粉棒束孢8个当地居群和蝙蝠蛾拟青霉2个当地居群进行ITS测序和RAPD扩增分析,结合Gen Bank中相关序列,对粉棒束孢开展遗传多样性、居群遗传结构及其种内分化研究。共获得大范围内地理距离远的6个居群共97条粉棒束孢ITS序列,共有33种单倍型,单倍型多样性Hd=0.546和总核苷酸多样性Pi=0.00276,显示粉棒束孢在物种水平上遗传多样性较低。云南粉棒束孢共37条序列,有14种单倍型(10种为云南特有),具有较高单倍型多样性和核苷酸多样性(Hd=0.659,Pi=0.00274);单倍型聚类和网状分支分析表明云南粉棒束孢单倍型类型丰富,遗传多样性高,暗示云南为粉棒束孢多样性分布中心之一。ITS序列分析表明,云南当地居群间遗传分化系数Fst=51.95%;RAPD分析表明,居群间遗传分化系数Gst=0.5547,基因流Nm=0.4014;说明云南当地居群粉棒束孢分化剧烈。居群遗传距离与地理距离相关性研究表明,粉棒束孢居群遗传距离与地理距离无明显相关。中性检验和失配分析表明粉棒束孢经历过近期居群扩张。结合单倍型聚类和网状分支分析,表明Hap 19为扩张建群单倍型,但原始祖先单倍型(Hap 1)依然是粉棒束孢居群中最优势单倍型(频率为48.45%),表明粉棒束孢并不存在明显的因地理原因造成的生殖隔离。值得重视的是,通过ITS单倍型和RAPD分析,支持将蝙蝠蛾拟青霉作为粉棒束孢异名处理。  相似文献   
2.
稻螟赤眼蜂Trichogramma japonicum Ashmead是二化螟Chilo suppressalis(Walker)和稻纵卷叶螟Cnaphalocrocis medinalis(Guenée)的优势卵寄生蜂。为优化稻螟赤眼蜂田间释放技术,作者分别在安徽、福建和贵州进行了稻螟赤眼蜂不同释放高度和密度对防控两种水稻螟虫效果影响的田间试验。结果表明,对于防控稻纵卷叶螟,释放量一定时,赤眼蜂在稻株顶部以上5 cm高度、8点/0.07 hm 2释放密度的防治效果优于其他释放密度和高度的处理。而对于防控二化螟,不同释放高度对赤眼蜂防治效果差异不显著。  相似文献   
3.

Background

Metarhizium anisopliae, a soil-borne entomopathogen found worldwide, is an interesting fungus for biological control. However, its efficacy in the fields is significantly affected by environmental conditions, particularly moisture. To overcome the weakness of Metarhizium and determine its isolates with antistress capacity, the efficacies of four M. anisopliae isolates, which were collected from arid regions of Yunnan Province in China during the dry season, were determined at different moisture levels, and the efficacy of the isolate MAX-2 from Shangri-la under desiccation stress was evaluated at low moisture level.

Results

M. anisopliae isolates MAX-2, MAC-6, MAL-1, and MAQ-28 showed gradient descent efficacies against sterile Tenebrio molitor larvae, and gradient descent capacities against desiccation with the decrease in moisture levels. The efficacy of MAX-2 showed no significant differences at 35% moisture level than those of the other isolates. However, significant differences were found at 8% to 30% moisture levels. The efficacies of all isolates decreased with the decrease in moisture levels. MAX-2 was relatively less affected by desiccation stress. Its efficacy was almost unaffected by the decrease at moisture levels > 25%, but slowly decreased at moisture levels < 25%. By contrast, the efficacies of other isolates rapidly decreased with the decrease in moisture levels. MAX-2 caused different infection characteristics on T. molitor larvae under desiccation stress and in wet microhabitat. Local black patches were found on the cuticles of the insects, and the cadavers dried without fungal growth under desiccation stress. However, dark black internodes and fungal growth were found after death of the insects in the wet microhabitat.

Conclusions

MAX-2 showed significantly higher efficacy and superior antistress capacity than the other isolates under desiccation stress. The infection of sterile T. molitor larvae at low moisture level constituted a valid laboratory bioassay system in evaluating M. anisopliae efficacy under desiccation stress.  相似文献   
4.
肠道共生细菌预发酵鸡粪对黑水虻生长发育的影响   总被引:1,自引:0,他引:1  
喻国辉  杨紫红  夏嫱  陈远凤  程萍 《昆虫知识》2010,47(6):1123-1127
以利用黑水虻Hermetia illucens L.肠道共生细菌不同菌株培养液预发酵的鸡粪为培养料,研究了添加不同菌株的发酵鸡粪对黑水虻幼虫生长发育的影响。结果表明,添加不同菌株的预发酵鸡粪能显著增加预蛹和蛹的重量,显著提高化蛹率并增加雌、雄成虫体长,缩短预蛹所需时间,但对幼虫存活率、成虫羽化率、成虫寿命没有显著影响。同时,不同菌株的作用效果有所不同。  相似文献   
5.
A new species of Ophiocordyceps, Ophiocordyceps lanpingensis collected from Lanping County, Yunnan Province, southwestern China, was described based on morphological characteristic, ITS1-5.8S-ITS2 rDNA sequences analyses, 5-gene (nrSSU, nrLSU, tef-1α, rpb1 and rpb2) sequences analyses and MAT1-2-1 gene sequences analyses. This species was characterized by thinner stroma, smaller perithecium, thinner ascospore (multiseptate with short septation). The phylogenetic analyses based on the ITS, the 5-gene and MAT1-2-1 gene dataset showed O. lanpingensis had the closest evolution relationship with O. robertsii and O. sinensis, but still had obvious distances to them. Both morphological character and systematic analyses supported that O. lanpingensis was a new species of Ophiocordyceps.  相似文献   
6.
To study the transferability of rice (Oryza sativa L.) genome data, we used amplified consensus genetic markers to analyze the phylogenetic relationships among several species and genera in Gramineae. Ten accessions representing five grass genera (Oryza, Zea, Setaria, Triticum, and Phyllostachys) were used. According to the genetic distances, a cluster tree was constructed. The relationships among the five genera could be simply described as ((Oryza + (Zea + Setaria)) + Triticum) + Phyllostachys. The results suggest that the genetic distance between rice and maize (Z. mays L.) or rice and millet (Setaria italica L.) is closer than that between rice and wheat (Triticum aestivum L) or rice and bamboo.  相似文献   
7.
应用ACGM标记分析禾本科几个物种间的系统发生关系   总被引:3,自引:0,他引:3  
卢泳全  叶子弘  吴为人 《遗传学报》2006,33(12):1127-1131
为了验证水稻基因组数据的通用性,利用ACGM标记分析了禾本科几个不同种属植物的亲缘关系。选用10份材料,它们分别代表禾本科的5个属(Oryza,Zea, Setaria ,Triticum,和Phyllostachys)。根据遗传距离建立了一个聚类树。这5个属的亲缘关系可以简单地表示为:((Oryza+(Zea+Setaria))+Triticum)+Phyllostachys。研究结果表明,水稻与玉米或水稻与粟之间的遗传距离比水稻和小麦或水稻与竹子之间的遗传距离近。  相似文献   
8.
The aim of this study was to determine the association between the rs6552828 polymorphism in acyl coenzyme A synthetase (ACSL1) and elite endurance athletic status. We studied 82 Caucasian (Spanish) World/Olympic-class endurance male athletes, and a group of sex and ethnically matched healthy young adults (controls, n=197). The analyses were replicated in a cohort of a different ethnic origin (Chinese of the Han ethnic group), composed of elite endurance athletes (runners) [cases, n=241 (128 male)] and healthy sedentary adults [controls, n=504 (267 male)]. In the Spanish cohort, genotype (P=0.591) and minor allele (A) frequencies were similar in cases and controls (P=0.978). In the Chinese cohort, genotype (P=0.973) and minor allele (G) frequencies were comparable in female endurance athletes and sedentary controls (P=0.881), whereas in males the frequency of the G allele was higher in endurance athletes (0.40) compared with their controls (0.32, P=0.040). The odds ratio (95%CI) for an elite endurance Chinese athlete to carry the G allele compared with ethnically matched controls was 1.381 (1.015-1.880) (P-value=0.04). Our findings suggest that the ACSL1 gene polymorphism rs6552828 is not associated with elite endurance athletic status in Caucasians, yet a marginal association seems to exist for the Chinese (Han) male population.  相似文献   
9.
菰黑粉菌的分离鉴定及其发酵液中植物激素的检测   总被引:1,自引:0,他引:1  
在显微镜下观察孢子形态,并观察单菌落的形态和菌株的微观形态,PCR扩增其ITS-5.8S rDNA序列,测序并在NCBI中进行同源比较,确定其种属。液体培养该菌株,通过高效液相色谱法检测发酵液中植物激素。结果表明:用菌落形态与孢子形态鉴定和分子生物学鉴定的方法,对茭白中分离的一个菌株鉴定为菰黑粉菌,且在其发酵液中检测到植物激素IAA、ABA和GA3,其中IAA含量为0.1306mg/L,ABA含量为0.01367mg/L。  相似文献   
10.
数量性状发育遗传模型及其分析方法的研究进展   总被引:10,自引:0,他引:10  
叶子弘  朱军 《遗传》2001,23(1):65-68
发育遗传模型是同时反映性状遗传和发育本质、提供影响遗传变异及调整发育进程的有关因素的信息的模型。建立在群体遗传学基础上的直接效应模型适用于单一基因控制的简单性状。渐成模型将遗传变异分解成直接分量和渐成分量(母体效应和互作效应),能更好地反映有机体遗传和发育的生物学机制。生长轨迹模型有效地综合了复杂性状各分量的发育动态,可获得连续的、综合的、详细的、动态的发育信息。条件遗传分析方法不仅可以估算特定时间段的净效应,且可将净效应分解为不同遗传分量,了解各效应分量的相对贡献。 Abstract:Developmental genetic models and analysis methods for quantitative traits are presented.Developmental genetic models should reflect the genetic and developmental essence,and provide the information of the factors influencing the genetic variation and the developmental process.Direct effect models,which based on the population genetics,may be suitable to analyze simple traits with single gene.Epigenetic models can decompose the whole genetic variation into direct and epigenetic components (maternal effects and epigenetic interaction effects),so that biological mechanism can be better understood.Growth trace models effectively synthesize the developmental dynamics of components of complex traits.With them,continuous,compositive,detailed,and dynamic information of development is available.Conditional analysis method can not only estimate the net effects in a specific time interval,but also depose them into genetic components and help to appreciate the contributions of different effects.  相似文献   
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