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1.
R. G. Freitas R. F. Alfenas L. M. S. Guimarães J. L. Badel A. C. Alfenas 《Plant pathology》2019,68(5):869-877
Calonectria leaf blight, caused by Calonectria pteridis, is currently one of the main foliar diseases in eucalypt plantations in Brazil. In warm and high rainfall regions, the disease can be a limiting factor for eucalypt production when planting susceptible genotypes. The most effective method for controlling this disease in the field is the use of resistant genotypes, which requires knowledge of the genetic variability and aggressiveness of the pathogen population for effective deployment of plant resistance. This work evaluated the genetic diversity and aggressiveness of C. pteridis populations obtained from infected eucalypt plants in Monte Dourado (Pará state) and Imperatriz (Maranhão state), Brazil. To study the genetic diversity, 16 ISSR primers were tested, five of which amplified polymorphic, reproducible and informative bands. Thirty-one closely related genotypes were identified from 84 isolates studied, indicating that the population has a low genetic diversity. The aggressiveness of seven isolates, selected according to geographic origin and their clustering in the ISSR-based dendogram, was determined by inoculation of a hybrid Eucalyptus grandis × E. urophylla clone under controlled conditions. Disease severity was assessed by both measuring the percentage of plant defoliation and assigning a score according to a diagrammatic scale of symptoms. A high correlation between the two evaluation methods was observed, which revealed significant differences in aggressiveness among the isolates. The diagrammatic scale is recommended for disease evaluation because results are obtained much faster, before the occurrence of severe defoliation. No correlation between clustering in the ISSR-based phylogenetic analysis and aggressiveness was observed. 相似文献
2.
为建立高效的朱顶红植株再生和种苗繁育技术体系,以幼嫩花梗为外植体开展胚性愈伤组织诱导和植株再生研究。对2,4-D和噻苯隆(TDZ)浓度、外植体发育时期及大小进行了筛选,结果表明:将切片厚度为1 mm的幼嫩花梗外植体置于添加0.5 mg ? L-1 TDZ 和2.0 mg ? L-1 2,4-D的MS固体培养基上培养8周,胚性愈伤组织诱导率最高,达85.3%。将胚性愈伤组织转移至相同的培养基上,每月继代1次,平均每月增殖10.6倍。在不含任何生长调节剂的MS培养基上,胚性愈伤组织的植株再生率达98.0%,平均每块愈伤组织可再生出12.3个小植株。经过36次(3年)继代培养后,胚性愈伤组织的增殖和植株再生效率没有显著变化。幼苗移栽至温室驯化,成活率达97.5%。再生植株移栽到田间,没有发现明显的表型变异。对随机选择的再生植株和母株进行简单序列重复区间(ISSR)扩增分析,证实再生植株没有发生DNA水平变异。 相似文献
3.
利用ISSR分子标记技术对144份木棉(Bombax ceiba)种质资源遗传多样性进行分析。结果表明: 木棉种质资源具有较高的遗传多样性,采用筛选的26个ISSR引物共扩增出179个位点,多态性位点161个,多态性位点百分率为899%,有效等位基因数为16,Nei基因多样性指数为0350 5, Shannon信息多样性指数为0523 3,相似性系数为0238 6~0910 6。UPGMA聚类分析得出,木棉种质之间的亲缘关系与来源没有明显的相关性,对同一产地来说,绝大部分种质聚在一起,亲缘关系较近,同时不同产地之间多数木棉种质亲缘关系也较近。 相似文献
4.
凤凰单丛茶树资源遗传多样性的ISSR分析 总被引:3,自引:0,他引:3
采用ISSR分子标记技术对48份凤凰单丛茶品种(系)进行了遗传多样性分析。选用10个多态性高、分辨力强的ISSR引物分别对供试材料基因组DNA进行扩增,共获得121个位点,其中多态位点带98个,多态位点比率(PPB)为81.0%。品种(系)之间的遗传相似系数变化范围在0.590 9~0.967 4之间。UPGMA聚类分析结果表明,在GS值为0.792的水平上供试材料可划分为7大类,其亲缘关系远近与地理来源关系不大且与香味类型没有必然的联系。 相似文献
5.
6.
In this study, we report the use of ISSR to assess genetic diversity and to determine the relationships among ten cultivars
of common bean developed in Argentina and three materials from France. ISSR markers resolved two major groups corresponding
to the Andean and Mesoamerican gene pools of common bean. We compared the results of previous analysis, performed with RAPD
markers (Galván et al., 2001), with the results generated by means of ISSR. It appears that ISSR are better tools than RAPDs
to identify beans by gene pool of origin though they did not revealed as many differences between individuals as RAPDs.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
7.
Amit Kaushik Navinder Saini Sunita Jain Poonam Rana R.K. Singh Rajinder K. Jain 《Euphytica》2003,134(2):231-238
Segregation for salinity tolerance and ISSR markers based molecular polymorphism were investigated in a F3 plant population raised via single-seed descent method from a cross between salt-tolerant indica rice variety CSR10 and salt-susceptible
premium traditional Basmati rice variety Taraori Basmati HBC19. A total of 130 F3plants were evaluated individually for salinity tolerance on 1–9 scale on the basis of seedling growth parameters; the average
score ranged between 1.7 to 8.3. Frequency distribution curve obtained using the salinity tolerance data of F3 population and a chi-square analysis, showed a good fit to a normal distribution. Eleven plants each in the category of salt-tolerant
and salt-susceptible were selected from the segregating F3 population for ISSR marker analysis. A total of 149 bands (4–11 bands per primer) ranging from 200 to 3530 bp were scored
for the two rice varieties and the selected CSR10 × HBC19 segregating F3 plants using 26 ISSR primers. Of these, 89 were monomorphic and 60 were polymorphic. Of the 60 polymorphic bands,36 and 20
bands were specific to CSR10 andHBC19 respectively. The remaining four bands were amplified using UBC primers 810,848, 853
and 886 and present in only some of the CSR10 × HBC19 F3 plants. Notably, ISSR primers with dinucleotide repeat motif and 5'-anchored end amplified more number of bands (7.0 bands/primer)
compared to3'-anchored dinucleotide primers (5.4bands/primer), but 3'-anchored dinucleotide primers revealed higher level
of polymorphism (2.6 polymorphic bands/primer) compared to 5'-anchoreddinucleotide primers (1.43 polymorphic bands/ primer).
While distribution of majority of the polymorphic bands were more or less in the expected ratios in salt-tolerant and/or salt-sensitive
F3segregating plants, but some of the bands amplified using UBC ISSR primers 823, 825,826, 849, 853, 864, 866 and 884 showed
highly skewed distribution. Such polymorphic bands stand greater chances of having a linkage with the genes/ QTLs for salinity
tolerance and shall be the target for further studies.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
8.
新疆8个棉花品种(系)的指纹图谱分析 总被引:2,自引:0,他引:2
利用ISSR对8个新疆品种(系)进行指纹图谱构建。通过基因组多态性分析,从60条引物中筛选到11条扩增效果好的引物,用其中2条引物UBC809,UBC841建立8个品种的指纹图谱,统计品种鉴定的置信概率达到1/8388608。结果显示,ISSR分子标记技术对棉花品种的指纹图谱构建具有高效性和准确性。 相似文献
9.
12个水稻光温敏核不育系的ISSR标记鉴定及遗传分析 总被引:17,自引:0,他引:17
应用ISSR技术对12个水稻光温敏核不育系进行DNA指纹分析,筛选到13个生态性丰富的引物,共获得169个多态性DNA片段,选择其中的3个引物扩增出的8个多态性DNA片段可作为鉴定标记,能够正确区分供试的12个水稻光温敏核不育系。根据多态性片段的有无,将鉴定标记转换为数字1和0,建立了12个水稻光温敏核不育系相应的ISSR标记鉴定识别码。由Nei‘s,遗传距离创建的聚类分析表明,12个材料被聚为两大类群,4个梗型不育系聚为一类,其余8个籼型不育系聚为另一类,在籼稻群内,3个来源于安农S-1的不育系单独聚为一类,与来源于农垦58S的材料有明显的遗传差异。研究结果表明,ISSR标记具有简便、快速、多态性丰富等优点,可用于构建DNA指纹图谱,进行品种鉴定和遗传分析。 相似文献
10.