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121.
Assessment of genetic diversity within and among Basmati and non-Basmati rice varieties using AFLP,ISSR and SSR markers 总被引:6,自引:0,他引:6
Molecular markers provide novel tools to differentiate between the various grades of Basmati rice, maintain fair-trade practices and to determine its relationship with other rice groups in Oryza sativa. We have evaluated the genetic diversity and patterns of relationships among the 18 rice genotypes representative of the traditional Basmati, cross-bred Basmati and non-Basmati (indica and japonica) rice varieties using AFLP, ISSR and SSR markers. All the three marker systems generated higher levels of polymorphism and could distinguish between all the 18 rice cultivars. The minimum number of assay-units per system needed to distinguish between all the cultivars was one for AFLP, two for ISSR and five for SSR. A total of 171 (110 polymorphic), 240 (188 polymorphic) and 160 (159 polymorphic) bands were detected using five primer combinations of AFLP, 25 UBC ISSR primers and 30 well distributed, mapped SSR markers, respectively. The salient features of AFLP, ISSR and SSR marker data analyzed using clustering algorithms, principal component analysis, Mantel test and AMOVA analysis are as given below: (i) the two traditional Basmati rice varieties were genetically distinct from indica and japonica rice varieties and invariably formed a separate cluster, (ii) the six Basmati varieties developed from various indica × Basmati rice crosses and backcrosses were grouped variably depending upon the marker system employed; CSR30 and Super being more closer to traditional Basmati followed by HKR228, Kasturi, Pusa Basmati 1 and Sabarmati, (iii) AFLP, ISSR and SSR marker data-sets showed moderate levels of positive correlation (Mantel test, r = 0.42–0.50), and (iv) the partitioning of the variance among and within rice groups (traditional Basmati, cross-bred Basmati, indica and japonica) using AMOVA showed greater variation among than within groups using SSR data-set, while reverse was true for both ISSR and AFLP data-sets. The study emphasizes the need for using a combination of different marker systems for a comprehensive genetic analysis of Basmati rice germplasm. The high-level polymorphism generated by SSR, ISSR and AFLP assays described in this study shall provide novel markers to differentiate between traditional Basmati rice supplies from cheaper cross-bred Basmati and long-grain non-Basmati varieties at commercial level.The first two authors have equal contribution 相似文献
122.
Numerical Simulation on Drying Characteristics of a Combined Microwave-convection Process 总被引:1,自引:0,他引:1
Combined microwave-convection drying characteristics are investigated by numerical simulation. Combined microwave-convection drying has advantage of swift drying and sterilization. Based on qualitative analyses on the mechanism of combined microwave-convection drying, the differential equations are established and the numerical simulation method is described. The humidity, vapor pressure and temperature, along the radius in a spherical pill, are calculated by the numerical simulation during drying process. The calculation results show the relationship between humidity, vapor pressure, temperature and drying time, and that drying process is greatly influenced by input microwave power. The calculation results are good consistent with the experimental datum. 相似文献
123.
124.
Oligonucleotide fingerprinting of tomato DNA 总被引:6,自引:0,他引:6
D. Kaemmer K. Weising B. Beyermann T. Börner J. T. Epplen G. Kahlm 《Plant Breeding》1995,114(1):12-17
Hinfl -digested DNA samples of wild and cultivated species of tomato were hybridized in gel to different oligonucleotide probes complementary to simple-sequence repeats. All motifs tested i.e. (GATA)4, (GGAT)4, (CA)8. (CAG)5, (GTG)5, (GAAGTGGG)2 and (CCTA)4, produced multilocus fingerprints in all tomato species and cultivars. The extent of inter- and intraspecific polymorphism of the banding patterns varied considerably between different probes, with (GGAT)4, (CCTA)4, (GATA)4 and (CA)8 showing a much higher discriminatory potential than the other probes. Cluster analysis of band-sharing data yielded dendrograms which were consistent with the known history of tomato cultivation. (GATA)4 was also successfully used for purity testing of breeding lines, as well as for analysing an F1 progeny of a cross between two lines. 相似文献
125.
Summary Soybean DNA fingerprints were analyzed by digoxigenin-labeled oligonucleotide probes complementary to simple repetitive sequences. The clearest and most polymorphic patterns were obtained with (AAT)6 as a probe, with which all 47 soybean cultivars tested could be distinguished. However, DNA fingerprints of individuals within cultivars showed the same pattern. Using (CT)8, (GAA)5 or (AAGG)4 as probes, clear polymorphic patterns among cultivars and accessions in the subgenus Soja (Glycine max and Glycine soja) were not observed, while quite different patterns were found in accessions in the subgenus Glycine. The results suggest that G. max and G. soja are closer in their genome structure. DNA fingerprints of reciprocal crosses between cultivars and accessions in the subgenus Soja were similar, and contained bands of both parents. In an F2 population from these crosses, such bands segregated in a Mendelian fashion. 相似文献
126.
Strawberry-cultivar Identification using Randomly Amplified Polymorphic DNA (RAPD) Markers 总被引:3,自引:0,他引:3
Accurate and rapid cultivar identification is important for breeders'-rights protection, especially for vegetatively propagated plants. The objective of this study was to test the feasibility of developing cultivar-specific RAPD markers in commercial strawberries (Fragaria ananassa Dutch). Efforts were focused on distinguishing between two newly developed Volcani cultivars, ‘Ofra’ and ‘Dorit’, and six other cultivars, ‘Douglas’, ‘Chandler’, ‘Oso Grande’, ‘Dover’, ‘Nurit’ and ‘Parker’. Reproducible RAPD fingerprints were generated, each containing at least one polymorphic DNA product. A combination of 10 polymorphic DNA products exhibited cultivar-specific patterns enabling the distinction between closely related varieties, such as ‘Ofra’ (which is the progeny of ‘Dorit’ and ‘Parker’) and ‘Dorit’ (which is the progeny of ‘Nurit’ and ‘Dover’). This study shows that RAPD markers can help in the protection of breeders’ rights to strawberry cultivars. 相似文献
127.
128.
不同基因型刺梨及其近缘种亲缘关系的RAPD分析* 总被引:2,自引:0,他引:2
采用RAPD标记,对刺梨(Rosa roxburghii Tratt)7个基因型及8个近缘种(类型)进行鉴定和亲缘关系分析。结果表明,筛选出的16个随机引物可扩增出137条480bp到3.3kb大小的清晰。DNA片段,其中95条为多态性片段,为总数的69.3%;每个引物平均产生8.6条。由OPB-11、OPAF-16和OPW-02扩增的14条特异DNA片段,可有效地将普通刺梨7个基因型和无籽刺梨区分开来。基于遗传距离矩阵,采用IJPGMA法对15个供试样品的亲缘关系进行了聚类分析,文中还就无籽刺梨及重瓣刺梨的可能来源进行了探讨。 相似文献
129.
渠井结合灌区适宜渠井用水比例关系灌区地下水环境和区域农业可持续发展。该文以人民胜利渠灌区为例,集合了灌区1954-2014年农业用水量及降水量、研究区域2008-2014年渠井用水比、地下水埋深、地下水水化学特征数据,分析了降雨量、地下水动态特征与渠井用水比例的相关性,以期探明渠井结合灌区渠井用水比对降雨的响应及其对土壤和地下水环境的影响。结果表明,典型渠井结合灌区渠井用水比与年降水量呈线性正相关;渠系上游地下水水位变化较下游更为剧烈,在用水水平、用水方式一致条件下,渠井用水比例越大,地下水埋深超过11 m区域增幅越小,较大的渠井用水比例对于上游地下水位下降减缓效果明显;平水期、枯水期,由于渠井用水比例不合理,地下水无序开采且超采严重,区域地下水碱化趋势明显;受气候变化影响,近5 a渠灌水量仅为多年均值的75.52%,未来区域降水量具有减小趋势,这势必进一步加剧农业水资源紧缺的形式。为了满足农业的正常生产,增加灌区地下水开采成为唯一解决途径,这势必加剧地下水的碱化趋势及地下水超采区的扩大。因此,确定灌区适宜的渠井用水比例对于灌区水资源的科学利用与农业的可持续发展具有重要意义。 相似文献
130.