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
Interspecific and intergeneric hybridizations have been widely used in plant genetics and breeding to construct stocks for genetic analysis and to introduce into crops the desirable traits and genes from their relativ...Interspecific and intergeneric hybridizations have been widely used in plant genetics and breeding to construct stocks for genetic analysis and to introduce into crops the desirable traits and genes from their relatives. The intergeneric crosses between Brassica juncea (L.) Czern. & Coss., B. carinata A. Braun and Orychophragmus violaceus (L.) O. E. Schulz were made and the plants produced were subjected to genomic in situ hybridization analysis. The mixoploids from the cross with B. juncea were divided into three groups. The partially fertile mixoploids in the first group (2n = 36—42) mainly contained the somatic cells and pollen mother cells (PMCs) with the 36 chromosomes of B. juncea and additional chromosomes of O. violaceus. The mixoploids (2n = 30—36) in the second and third groups were morphologically quite similar to the mother plants B. juncea and showed nearly normal fertility. The plants in the second group produced the majority of PMCs (2n = 36) with their chromosomes paired and segregated normally, but 1—4 pairs of the O. violaceus chromosomes were included in some PMCs. The plants in the third group produced only PMCs with the 36 B. juncea chromosomes, which were paired and segregated normally. The mixoploids (2n = 29—34) from the cross with B. carinata produced the majority of PMCs (2n = 34) with normal chromosome pairing and segregation, but some plants had some PMCs with 1—3 pairs of chromosomes from O. violaceus and other plants had only PMCs with the B. carinata chromosomes. The Brassica homozygous plants and aneuploids with complete or partial chromo-some complements of Brassica parents and various numbers of O. violaceus chromosomes were derived from these progeny plants. The results in this study provided the molecular cytogenetic evidence for the separation of parental genomes which was previously proposed to occur in the hybridizations of these two genera.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 (Grant No. 30070413) and China Scholarship Council. References
文摘Interspecific and intergeneric hybridizations have been widely used in plant genetics and breeding to construct stocks for genetic analysis and to introduce into crops the desirable traits and genes from their relatives. The intergeneric crosses between Brassica juncea (L.) Czern. & Coss., B. carinata A. Braun and Orychophragmus violaceus (L.) O. E. Schulz were made and the plants produced were subjected to genomic in situ hybridization analysis. The mixoploids from the cross with B. juncea were divided into three groups. The partially fertile mixoploids in the first group (2n = 36—42) mainly contained the somatic cells and pollen mother cells (PMCs) with the 36 chromosomes of B. juncea and additional chromosomes of O. violaceus. The mixoploids (2n = 30—36) in the second and third groups were morphologically quite similar to the mother plants B. juncea and showed nearly normal fertility. The plants in the second group produced the majority of PMCs (2n = 36) with their chromosomes paired and segregated normally, but 1—4 pairs of the O. violaceus chromosomes were included in some PMCs. The plants in the third group produced only PMCs with the 36 B. juncea chromosomes, which were paired and segregated normally. The mixoploids (2n = 29—34) from the cross with B. carinata produced the majority of PMCs (2n = 34) with normal chromosome pairing and segregation, but some plants had some PMCs with 1—3 pairs of chromosomes from O. violaceus and other plants had only PMCs with the B. carinata chromosomes. The Brassica homozygous plants and aneuploids with complete or partial chromo-some complements of Brassica parents and various numbers of O. violaceus chromosomes were derived from these progeny plants. The results in this study provided the molecular cytogenetic evidence for the separation of parental genomes which was previously proposed to occur in the hybridizations of these two genera.
