In order to determine the potential for haploid induction via in vitro gynogenesis in tomato, the ovules and protoplasts of embryo sacs from the hybrids Zhongza 101 and Zhongza 105 were cultured. An efficient method o...In order to determine the potential for haploid induction via in vitro gynogenesis in tomato, the ovules and protoplasts of embryo sacs from the hybrids Zhongza 101 and Zhongza 105 were cultured. An efficient method of ovule isolation was established in this study. Using this method, 100-150 ovules could be isolated from one ovary. Isolated ovules were cultured on three induction media to induce gynogenesis in vitro. During culture, ovules were enlarged markedly, with opaque white color. When observed microscopically, there were cell divisions and cell clumps in embryo sacs. Subsequently, the cell clumps in embryo sacs ceased growth, likely because the integument grew faster than embryo sacs did and hindered the fiarther development of embryo sacs. Therefore, subsequent callus morphogenesis might be originated from the integument. Thousands ofcalli from the two tomato varieties were obtained. Five diploid plants were regenerated after 15 months of subculturing. To eliminate the hindering effect of integument on embryo sac cells, the protoplasts of embryo sacs were prepared and cultured. After 48 hours of culture, the protoplasts of embryo sacs doubled in size and gradually formed clusters of cells. These results suggested that gynogenesis might be a potential way for haploid induction in tomato.展开更多
MicroRNAs （miRNAs） are -21 nucleotide （nt）, endogenous RNAs that regulate gene expression in plants. Increasing evidence suggests that miRNAs play an important role in species-specific development in plants. Howev...MicroRNAs （miRNAs） are -21 nucleotide （nt）, endogenous RNAs that regulate gene expression in plants. Increasing evidence suggests that miRNAs play an important role in species-specific development in plants. However, the detailed miRNA profile divergence has not been performed among tomato species. In this study, the small RNA （sRNA） profiles of Solanum lycopersicum cultivar 9706 and Solanum habrochaites species PI 134417 were obtained by deep sequencing. Sixty-three known miRNA families were identified from these two species, of which 39 were common. Further miRNA profile comparison showed that 24 known non-conserved miRNA families were species-specific between these two tomato species. In addition, six conserved miRNA families displayed an apparent divergent expression pattern between the two tomato species. Our results suggested that species-specific, non-conserved miRNAs and divergent expression of conserved miRNAs might contribute to developmental changes and phenotypic variation between the two tomato species. Twenty new miRNAs were also identified in S. lycopersicum. This research significantly increases the number of known miRNA families in tomato and provides the first set of small RNAs in S. habrochaites. It also suggests that miRNAs have an important role in species-specific plant developmental regulation.展开更多
The idea behind this study is to show that using high yield genes from a wild tomato can enrich tomato breeding resources and accelerate tomato breeding programs. In this study, the near-isogenic line TA1229 containin...The idea behind this study is to show that using high yield genes from a wild tomato can enrich tomato breeding resources and accelerate tomato breeding programs. In this study, the near-isogenic line TA1229 containing a 24-cM introgression at the bottom of chromosome 1 from Lycopersicon acc. LA1777, affects several higher yield traits. The TA1229×9706 BC1 population was analyzed by marker-assisted selection and the traits of the population were evaluated. Twenty-three recombinant individuals that carried a shorter segment than TA1229 were obtained. Among them, 16 lines with the chromosome 1 recombinant segment can increase tomato yield and a QTL affecting yield was found between TG53 and TG158. Sixteen recombinant lines are useful to improve the tomato variety.展开更多
基金supported by the National Natural Science Foundation of China(31171963)the Major Project of Chinese National Programs for Fundamental Research and Development(2011CB100600)
文摘In order to determine the potential for haploid induction via in vitro gynogenesis in tomato, the ovules and protoplasts of embryo sacs from the hybrids Zhongza 101 and Zhongza 105 were cultured. An efficient method of ovule isolation was established in this study. Using this method, 100-150 ovules could be isolated from one ovary. Isolated ovules were cultured on three induction media to induce gynogenesis in vitro. During culture, ovules were enlarged markedly, with opaque white color. When observed microscopically, there were cell divisions and cell clumps in embryo sacs. Subsequently, the cell clumps in embryo sacs ceased growth, likely because the integument grew faster than embryo sacs did and hindered the fiarther development of embryo sacs. Therefore, subsequent callus morphogenesis might be originated from the integument. Thousands ofcalli from the two tomato varieties were obtained. Five diploid plants were regenerated after 15 months of subculturing. To eliminate the hindering effect of integument on embryo sac cells, the protoplasts of embryo sacs were prepared and cultured. After 48 hours of culture, the protoplasts of embryo sacs doubled in size and gradually formed clusters of cells. These results suggested that gynogenesis might be a potential way for haploid induction in tomato.
基金supported by the National Basic Research Program of China (2009CB11900)the Special Fund for Agro-Scientific Research in the Public Interest, China (201003065)
文摘MicroRNAs （miRNAs） are -21 nucleotide （nt）, endogenous RNAs that regulate gene expression in plants. Increasing evidence suggests that miRNAs play an important role in species-specific development in plants. However, the detailed miRNA profile divergence has not been performed among tomato species. In this study, the small RNA （sRNA） profiles of Solanum lycopersicum cultivar 9706 and Solanum habrochaites species PI 134417 were obtained by deep sequencing. Sixty-three known miRNA families were identified from these two species, of which 39 were common. Further miRNA profile comparison showed that 24 known non-conserved miRNA families were species-specific between these two tomato species. In addition, six conserved miRNA families displayed an apparent divergent expression pattern between the two tomato species. Our results suggested that species-specific, non-conserved miRNAs and divergent expression of conserved miRNAs might contribute to developmental changes and phenotypic variation between the two tomato species. Twenty new miRNAs were also identified in S. lycopersicum. This research significantly increases the number of known miRNA families in tomato and provides the first set of small RNAs in S. habrochaites. It also suggests that miRNAs have an important role in species-specific plant developmental regulation.
基金supported by the Natural Science Foundation of Beijing(6042023)the Key Laboratory of Vegetable Genetics and Physiology,Ministry of Agriculture,China.
文摘The idea behind this study is to show that using high yield genes from a wild tomato can enrich tomato breeding resources and accelerate tomato breeding programs. In this study, the near-isogenic line TA1229 containing a 24-cM introgression at the bottom of chromosome 1 from Lycopersicon acc. LA1777, affects several higher yield traits. The TA1229×9706 BC1 population was analyzed by marker-assisted selection and the traits of the population were evaluated. Twenty-three recombinant individuals that carried a shorter segment than TA1229 were obtained. Among them, 16 lines with the chromosome 1 recombinant segment can increase tomato yield and a QTL affecting yield was found between TG53 and TG158. Sixteen recombinant lines are useful to improve the tomato variety.
