T6V#2S·6AL and T6V#4S·6DL translocation chromosomes developed from the cross of wheat and different Dasypyrum villosum accessions have good powdery mildew （PM） resistance, but their pairing and pyramiding ...T6V#2S·6AL and T6V#4S·6DL translocation chromosomes developed from the cross of wheat and different Dasypyrum villosum accessions have good powdery mildew （PM） resistance, but their pairing and pyramiding behavior remains unclear. Results in this study indicated that the pairing frequency rate of the two differently originated 6VS chromosomes in their F1 hybrid was 18.9% according to genomic in situ hybridization （GISH）; the PM resistance plants in the F2 generation from the cross between T6V#4S·6DL translocation line Pm97033 and its PM susceptible wheat variety Wan7107 was fewer than expected. However, the ratio of the resistant vs. the susceptible plants of 15：1 in the F2 generation derived from the cross between the two translocation lines of T6V#2S·6AL and T6V#4S·6DL fitted well. Plants segregation ratio （homozygous：heterozygous：lacking） revealed by molecular marker for T6V#4S·6DL or T6V#2S·6AL in their F2 populations fitted the expected values of 1：2：1 well, inferring that the pairing of the two alien chromosome arms facilitates the transmission of T6V#4S·6DL from the F1 to the F2 generation. A quadrivalent was also observed in 21% of pollen mother cells （PMCs） of homozygote plants containing the two pairs of translocated chromosomes. The chromosome pairing between 6V#2S and 6V#4S indicates that it will be possible to obtain recombinants and clarify if the PM resistance determinant on one alien chromosome arm is different from that on the other.展开更多
The supernumerary spikelets（SS）characters of tetraploid wheat（Triticum turgidum L.）resulting in more spikelets and kernels per spike,thus enhancing sink capacity may contribute to potential wheat yield improvement...The supernumerary spikelets（SS）characters of tetraploid wheat（Triticum turgidum L.）resulting in more spikelets and kernels per spike,thus enhancing sink capacity may contribute to potential wheat yield improvement.In order to investigate the effect of different SS types on agronomic characters and understand the genetic base of SS phenotype in tetraploid wheat,near isogenic lines（NILs）,bh-50 with normal spikelets（NS）,bh-51 with four-rowed spikelets（FRS）,bh-52 with short-ramified spikelets（SRS）,and bh-53 with long-ramified spikelets（LRS）in a Triticum durum cv.ZY1286 genetic background were developed by continuous backcrossing.Agronomic characters showed that the SS phenotype lines,bh-51,bh-52and bh-53 have significant increase in the number of spikelets and grains per spike compared with the NS phenotype line bh-50（P〈0.05）,and bh-53 line showed much more increase than those of bh-51 and bh-52.However,bh-53 had the lowest grain weight and the longest spike development stage than those of other spike phenotypes.These results indicated that the different SS types have different effects on the agronomic and spike characters.Genetic analysis through bh-50/bh-51and bh-51/bh-53 F2 populations showed that a recessive major gene controlled the spike architecture to transform from NS to FRS,and a dominant major gene determined the change of spike phenotype from FRS to RS.DNA sequences of Tt BH/WFZP ortholog on chromosome 2AS revealed that a single nucleotide polymorphism（SNP）substitution happened in the open reading frame（ORF）region of all the SS tetraploid wheat accessions,which may lead to the generation of lateral meristems between glume and lemma during the immature spike development.While the fates of the lateral meristems,developing into lateral spikelets or branched spikelets,may be determined by another major gene.Our results presented here may advance our understanding and knowledge of the genes and genetic pathways determining the spike architecture development in wheat.展开更多
基金financially supported by the National Key Research and Development Program,China (2016YFD0102000) the Agricultural Science and Technology Innovation Program (ASTIP) of the CAAS
文摘T6V#2S·6AL and T6V#4S·6DL translocation chromosomes developed from the cross of wheat and different Dasypyrum villosum accessions have good powdery mildew （PM） resistance, but their pairing and pyramiding behavior remains unclear. Results in this study indicated that the pairing frequency rate of the two differently originated 6VS chromosomes in their F1 hybrid was 18.9% according to genomic in situ hybridization （GISH）; the PM resistance plants in the F2 generation from the cross between T6V#4S·6DL translocation line Pm97033 and its PM susceptible wheat variety Wan7107 was fewer than expected. However, the ratio of the resistant vs. the susceptible plants of 15：1 in the F2 generation derived from the cross between the two translocation lines of T6V#2S·6AL and T6V#4S·6DL fitted well. Plants segregation ratio （homozygous：heterozygous：lacking） revealed by molecular marker for T6V#4S·6DL or T6V#2S·6AL in their F2 populations fitted the expected values of 1：2：1 well, inferring that the pairing of the two alien chromosome arms facilitates the transmission of T6V#4S·6DL from the F1 to the F2 generation. A quadrivalent was also observed in 21% of pollen mother cells （PMCs） of homozygote plants containing the two pairs of translocated chromosomes. The chromosome pairing between 6V#2S and 6V#4S indicates that it will be possible to obtain recombinants and clarify if the PM resistance determinant on one alien chromosome arm is different from that on the other.
基金supported by the State Transgenic Project, China (2014ZX08009-40B)the Fundamental Research Funds for the Central Universities, China (KYZ201303)
文摘The supernumerary spikelets（SS）characters of tetraploid wheat（Triticum turgidum L.）resulting in more spikelets and kernels per spike,thus enhancing sink capacity may contribute to potential wheat yield improvement.In order to investigate the effect of different SS types on agronomic characters and understand the genetic base of SS phenotype in tetraploid wheat,near isogenic lines（NILs）,bh-50 with normal spikelets（NS）,bh-51 with four-rowed spikelets（FRS）,bh-52 with short-ramified spikelets（SRS）,and bh-53 with long-ramified spikelets（LRS）in a Triticum durum cv.ZY1286 genetic background were developed by continuous backcrossing.Agronomic characters showed that the SS phenotype lines,bh-51,bh-52and bh-53 have significant increase in the number of spikelets and grains per spike compared with the NS phenotype line bh-50（P〈0.05）,and bh-53 line showed much more increase than those of bh-51 and bh-52.However,bh-53 had the lowest grain weight and the longest spike development stage than those of other spike phenotypes.These results indicated that the different SS types have different effects on the agronomic and spike characters.Genetic analysis through bh-50/bh-51and bh-51/bh-53 F2 populations showed that a recessive major gene controlled the spike architecture to transform from NS to FRS,and a dominant major gene determined the change of spike phenotype from FRS to RS.DNA sequences of Tt BH/WFZP ortholog on chromosome 2AS revealed that a single nucleotide polymorphism（SNP）substitution happened in the open reading frame（ORF）region of all the SS tetraploid wheat accessions,which may lead to the generation of lateral meristems between glume and lemma during the immature spike development.While the fates of the lateral meristems,developing into lateral spikelets or branched spikelets,may be determined by another major gene.Our results presented here may advance our understanding and knowledge of the genes and genetic pathways determining the spike architecture development in wheat.
