Genetic variation of rice cultivars of Taiwan

• Main Authors: Po-Chia Hung, 洪柏嘉
• Other Authors: Maw-Sun Lin
• Format: Others
• Language: zh-TW
• Published: 1995
• Online Access: http://ndltd.ncl.edu.tw/handle/91360181181201996474

碩士 === 國立中興大學 === 植物學系 === 83 === Pedigree analysis was performed for 11 Japonica rice (Oryza sativa L.)cultivars released between 1988-1994 and 19 Indicarice cultivars released between 1957-1988.Examination of pedigrees indicated that modern Taiwan Japonicae could be traced back to 68 ancestors.Two ancestors,''Shinriki'' and ''Kameji'',had the highest mean relative genetic contributions of the genes with 16 % and 12 %, respectively. The 10 most important ancestral contributors of the 11 Japonica rice collectively comprised 58% of genetic contribution. Germplasm of diverse sources and Indica type were incorperated to increase the genetic diversity.Modern Japonica rice varieties were developed with a broad genetic base. 19 Indica rice cultivars could be traced back to 44 ancestors. DGWG appeared most frequently in 19 Indica parentages and contributed 23% of the genetic constitution of the cultivars. Ten ancestors together comprised 77% in mean relative contribution. This result revealed the narrow genetic base in Indica rice cultivars. Cluster analysis produced two large groups of Japonica and Indica cultivars. Four small groups A'',B'', C'' and D'' of Japonica rice can be traced back to four predominant parents ''Taichung 65'', ''Kaohsiung 141'', ''Tainan 5''and ''Chianung line 702361'', respectively. Kaohsiung sel. 1, Taiken 1, Taiken 7 and Taiken 9 did not belong to any of these four groups. Three small groups E'', F'' and G'' of Indica rice can be traced back to three predominant parents of ''DGWG'', ''IR8'' and ''IR22''. The cluster analysis revealed that Indica rice cultivar are not broadly based, but reasonable genetic diversity occurs among these genotypes.