Erianthus arundinaceus is an important, closely related genus of Saccharum officinarum L. It is therefore important to understand how the chromosomes are transmitted when it hybridizes with sugarcane. The hybrids and ...Erianthus arundinaceus is an important, closely related genus of Saccharum officinarum L. It is therefore important to understand how the chromosomes are transmitted when it hybridizes with sugarcane. The hybrids and backcross progenies of S. officinarum and E. arundinaceus and their parents were used for Karyotype analysis and to study the law of chromosome transmission. The results showed that the somatic chromosome number of both of the E. arundinaceus Hainan92-105 and Hainan92-77 were 2n = 60 = 60sm, belonging to type 1 A, and the BC1 YC01-21 was 2n = 104 = 100m ＋ 4sm, belonging to type 2C. The other six tested clones belonged to type 2B. The both F1s YC96-66 and YC96-40 that originated from Badila （2n = 80 = 70m ＋ 10sm） with E. Arundinaceus were 2n = 70 = 68m ＋ 2sm, which suggests an n ＋ n transmission. The cross between YC96-66 （female parent） and CP84-1198 （male parent, 2n = 120 = 114m ＋ 6sm） also followed the same genetic law and the somatic chromosome number of their progeny, YC01-3 （2n = 105 = 95m ＋ 10sm）. The cross derived from YC96- 40 （female） and CP84-1198 （male）, YC01-21 had 2n = 104 = 100m ＋ 4sm chromosomes, following the same genetic law of n ＋ n. However, YC01-36 had 2n = 132 = 130m ＋ 2sm chromosomes, which suggests a 2n ＋ n chromosome transmission. It can be inferred that the inheritance of chromosomes was very complex in the BC1. The difference in chromosome number between clones was as high as 28. This could be explained by the 2n ＋ n transmission of chromosomes. In addition, as there was not be a regular number of haploids, this phenomenon is termed as disequilibrium hybridization.展开更多
To understand genetic structure and diversity of parental cultivars involved in China Mainland sugarcane breeding programs, 92 elite parents and 4 wild relatives were genotyped with 18 microsatellite DNA markers. The ...To understand genetic structure and diversity of parental cultivars involved in China Mainland sugarcane breeding programs, 92 elite parents and 4 wild relatives were genotyped with 18 microsatellite DNA markers. The genetic similarity （GS） values among the cultivars ranged from 0.346 to 0.960 with an average of 0.533. Among the introduced cultivars, India accessions had the closest genetic distance to China Mainland accessions （0.447）, while Australia accessions have the furthest distance （0.503）. A comparison of allelic diversity among geographical origins showed that there were 22 China Mainland specific alleles, of which 28% were derived from native S. spontaneaum germplasm in China. Model-based genetic structure, clustering, and principal components analyses consistently revealed there were five groups within the 96 accessions. Groups 1, 2, 4, and 5 consisted of all cultivars and group 3 only contained wild germplasm. Group 2 was characterized as the Introduction group with 46 cultivars predominantly introduced from Australia, Taiwan of China, India, and USA. Groups 1, 4, and 5 consisted of cultivars mostly originated from China Mainland, defined as the Complex group, Yacheng lines group, and F134/CP72-1210 group, respectively, upon their pedigree. By understanding the genetic relationships among the parental cultivars, breeders can gain a rational basis for expanding the gene pool and select the best parental accessions for crossing.展开更多
基金supported by the National Natural Science Foudation of China (30671329)the National Key Technologies R&D Program of Chinaduring the 11th Five-Year Plan period (2006BAD06-4)
文摘Erianthus arundinaceus is an important, closely related genus of Saccharum officinarum L. It is therefore important to understand how the chromosomes are transmitted when it hybridizes with sugarcane. The hybrids and backcross progenies of S. officinarum and E. arundinaceus and their parents were used for Karyotype analysis and to study the law of chromosome transmission. The results showed that the somatic chromosome number of both of the E. arundinaceus Hainan92-105 and Hainan92-77 were 2n = 60 = 60sm, belonging to type 1 A, and the BC1 YC01-21 was 2n = 104 = 100m ＋ 4sm, belonging to type 2C. The other six tested clones belonged to type 2B. The both F1s YC96-66 and YC96-40 that originated from Badila （2n = 80 = 70m ＋ 10sm） with E. Arundinaceus were 2n = 70 = 68m ＋ 2sm, which suggests an n ＋ n transmission. The cross between YC96-66 （female parent） and CP84-1198 （male parent, 2n = 120 = 114m ＋ 6sm） also followed the same genetic law and the somatic chromosome number of their progeny, YC01-3 （2n = 105 = 95m ＋ 10sm）. The cross derived from YC96- 40 （female） and CP84-1198 （male）, YC01-21 had 2n = 104 = 100m ＋ 4sm chromosomes, following the same genetic law of n ＋ n. However, YC01-36 had 2n = 132 = 130m ＋ 2sm chromosomes, which suggests a 2n ＋ n chromosome transmission. It can be inferred that the inheritance of chromosomes was very complex in the BC1. The difference in chromosome number between clones was as high as 28. This could be explained by the 2n ＋ n transmission of chromosomes. In addition, as there was not be a regular number of haploids, this phenomenon is termed as disequilibrium hybridization.
基金supported by the National Natural Science Foundation of China (30800700)the China Agriculture Research System
文摘To understand genetic structure and diversity of parental cultivars involved in China Mainland sugarcane breeding programs, 92 elite parents and 4 wild relatives were genotyped with 18 microsatellite DNA markers. The genetic similarity （GS） values among the cultivars ranged from 0.346 to 0.960 with an average of 0.533. Among the introduced cultivars, India accessions had the closest genetic distance to China Mainland accessions （0.447）, while Australia accessions have the furthest distance （0.503）. A comparison of allelic diversity among geographical origins showed that there were 22 China Mainland specific alleles, of which 28% were derived from native S. spontaneaum germplasm in China. Model-based genetic structure, clustering, and principal components analyses consistently revealed there were five groups within the 96 accessions. Groups 1, 2, 4, and 5 consisted of all cultivars and group 3 only contained wild germplasm. Group 2 was characterized as the Introduction group with 46 cultivars predominantly introduced from Australia, Taiwan of China, India, and USA. Groups 1, 4, and 5 consisted of cultivars mostly originated from China Mainland, defined as the Complex group, Yacheng lines group, and F134/CP72-1210 group, respectively, upon their pedigree. By understanding the genetic relationships among the parental cultivars, breeders can gain a rational basis for expanding the gene pool and select the best parental accessions for crossing.
