Population structure analysis in stylo [Stylosanthes sp.] using SSR markers (Record no. 290258)
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| 000 -LEADER | |
|---|---|
| fixed length control field | 04677nam a22001577a 4500 |
| 082 ## - DEWEY DECIMAL CLASSIFICATION NUMBER | |
| Classification number | 660.6 |
| Item number | FAT/PO PG |
| 100 ## - MAIN ENTRY--PERSONAL NAME | |
| Personal name | Fathima Zahra P M |
| 245 ## - TITLE STATEMENT | |
| Title | Population structure analysis in stylo [Stylosanthes sp.] using SSR markers |
| 260 ## - PUBLICATION, DISTRIBUTION, ETC. (IMPRINT) | |
| Place of publication, distribution, etc | Vellayani |
| Name of publisher, distributor, etc | Department of Plant Biotechnology, College of Agriculture |
| Date of publication, distribution, etc | 2022 |
| 300 ## - PHYSICAL DESCRIPTION | |
| Extent | 98p. |
| 502 ## - DISSERTATION NOTE | |
| Dissertation note | BSc - MSc (Int.) |
| 520 ## - SUMMARY, ETC. | |
| Abstract | Stylosanthes is a dominant pasture legume growing in tropical and subtropical regions of India and is extensively applied as forage and cover crop in agricultural systems. The fundamental concern with Stylosanthes is the restricted number of superior varieties. The genus Stylosanthes under the family Fabaceae comprises approximately 50 spp. distributed worldwide in the tropics among which S. scabra, S. seabrana, S. hamata and S. guianensis are predominant. The current study entitled “Population structure analysis in Stylo [Stylosanthes sp.] using SSR markers” was undertaken at College of Agriculture, Vellayani, Thiruvananthapuram to assess the genetic variability among Stylosanthes accessions using SSR markers and to construct the population structure of Stylosanthes genotypes thereby delimiting these species. In this study, 19 accessions of Stylosanthes which belong to the genotypes S. scabra, S. seabrana, S. hamata and S. guianensis were collected from IGFRI, Jhansi, Kerala Livestock Development Board and centres under AICRP on Forage Crops and Utilisation. The 19 accessions were characterized using fifty seven molecular markers and correlated with the available phenotypic data. The purity and concentration of DNA ranged from 1.63 to 1.96 and 525 ng/µl to 3024 ng/µl respectively, indicates that a good quality DNA obtained from the Stylosanthes species. Forty nine markers showed amplification and produced a total of 120 alleles among the 19 Stylosanthes accessions. Forty one showed polymorphic bands and they produced a total of 101 polymorphic alleles. The highest number of alleles was produced by gSsb-16 (6 alleles) and the polymorphism information content (PIC) for these markers revealed that gSsb-11, eSgu-29 and eScap-24 (0.48) have the highest PIC followed by gSsb-16 (0.477). S. hamata (T5) and S. seabrana (T18) showed more than one allelic band in a maximum number while S. seabrana Phule Kranti (T9) showed only one allelic band with the entire set of polymorphic markers A Bayesian model population structure study of these 19 Stylosanthes accessions using STRUCTURE v2.3.4 showed the existence of three gene pools (number of sub-population, k = 3). Also, the dendrogram generated using NTSYSpc v2.02e, based on 41 markers distinctively demarcated Stylosanthes accessions into five clusters indicating its vast genetic diversity in the 91 population. A maximum genetic similarity of 85.37% was shown by two pairs of accessions namely S. scabra ILCA140 (T1) with S. seabrana (T19) and S. scabra Fitzroy (T7) with S. seabrana (T13). A minimum genetic similarity of 48.78% was shown by S. guianensis CIAT (T10) with S. hamata (T11). Variance components analysis of seven phenotypic characteristics showed that the values of PCV and GCV was higher for leaf breadth, green fodder yield per plot and dry fodder yield per plot; high heritability coupled with high genetic advance was noted for green fodder yield per plot and dry fodder yield per plot. Cluster analysis based on phenotypic data divided the 19 Stylosanthes accessions into five clusters. The highest similarity was observed in S. scabra DRSS4-RRR94197 (T4) with S. seabrana (T14) at a similarity coefficient of 0.71. In the study, S. scabra with S. seabrana showed the highest genetic similarity within the genotypes in terms of molecular and phenotypic cluster analysis and the grouping was performed irrespective of the origin of genotypes. A better performance in phenotypic traits and molecular analysis was noticed in S. guianensis Reyan (T8) and S. guianensis CIAT (T10) showing their suitability in fodder improvement programmes of Stylosanthes species. Overall, the level of genetic variability and 76.9 per cent average polymorphism indicated by the primers in the current study suggests that SSR markers can be utilized for fodder improvement and genetic resource management and utilization. For proper validation of the results obtained, cytological studies of the Stylosanthes accessions, increasing the number of accessions in the different species and evaluation of more SSR markers need to be done. |
| 650 ## - SUBJECT ADDED ENTRY--TOPICAL TERM | |
| Topical term or geographic name as entry element | Plant Biotechnology |
| 700 ## - ADDED ENTRY--PERSONAL NAME | |
| Personal name | Gayathri G (Guide) |
| 942 ## - ADDED ENTRY ELEMENTS (KOHA) | |
| Source of classification or shelving scheme | |
| Item type | Theses |
| Not for loan | Collection code | Permanent location | Current location | Shelving location | Date acquired | Full call number | Barcode | Date last seen | Koha item type |
|---|---|---|---|---|---|---|---|---|---|
| Not For Loan | Reference Book | KAU Central Library, Thrissur | KAU Central Library, Thrissur | Theses | 2023-05-05 | 660.6 FAT/PO PG | 175685 | 2023-05-05 | Theses |