Graft can induce inheritable variations in the progenies of the scion plants. Seedling of mungbean ( Vigna radiata (L.) Wilczek) was grafted onto the stem of sweet potato ( Ipomoea batatas (L.) Lam.). The growth...Graft can induce inheritable variations in the progenies of the scion plants. Seedling of mungbean ( Vigna radiata (L.) Wilczek) was grafted onto the stem of sweet potato ( Ipomoea batatas (L.) Lam.). The growth of the scion was maintained until the scion produced selfed seeds. We sowed the seeds for several generations under normal conditions. Distinct genetic variations appeared in the progenies. Similar variations did not appear in the generations of the scion sowed normally without graft. The variations seemed to be induced by the graft and they inherited steadily. For understanding the possible mechanism of the phenomenon (graft_induced inheritable variation), we analyzed the cytoplasmic and genomic DNA of the variations. The results showed that there was no restriction fragment length polymorphism (RFLP) in the cytoplasmic DNA between the original scion and the variation. However, significant difference between the scion and variation was recognized by random amplified polymorphic DNA (RAPD) analysis. In addition, there was no evidence that indicated the gene transformation from stock to scion. Our results suggest that the non_specific grafting has a pragmatic potential for plant breeding and crop improvement and, the genetic variation seems not to be caused simply by DNA transformation but most likely the stress induced mutation.展开更多
Molybdenum （Mo） and Cobalt （Co） play an important role in nitrogen （N） metabolism of grain legumes. Their applications to alkaline soils have been scarcely studied. A field experiment was set up to evaluate the ...Molybdenum （Mo） and Cobalt （Co） play an important role in nitrogen （N） metabolism of grain legumes. Their applications to alkaline soils have been scarcely studied. A field experiment was set up to evaluate the Mo and Co application in common bean cv. Canario Centenario under two fertilization systems： inorganic fertilization and inoculation with Rhizobium etli. In each system, Mo and Mo ＋ Co were applied by seed impregnation at doses of 1.36 g/kg of seed for Mo and 0.26 g/kg of seed for Co; a control for each fertilization system and an absolute control were included. Yield components, nodules characteristics and N content by grains and foliage were evaluated. A completely randomized block design with seven treatments and five replications was used. Mo application increased the grain yield, grain size, nodulation and N accumulation in grains under both fertilization systems. Mo increased the total N uptake by the plant in 35.4% and 26%, for N fertilized and inoculated plants, respectively. Co application increased only nodules number and weight, and N content under inoculation. Mo application to beans cultivated in alkaline soils is recommended, but Co application is suitable only when beans are inoculated with rhizobia.展开更多
文摘Graft can induce inheritable variations in the progenies of the scion plants. Seedling of mungbean ( Vigna radiata (L.) Wilczek) was grafted onto the stem of sweet potato ( Ipomoea batatas (L.) Lam.). The growth of the scion was maintained until the scion produced selfed seeds. We sowed the seeds for several generations under normal conditions. Distinct genetic variations appeared in the progenies. Similar variations did not appear in the generations of the scion sowed normally without graft. The variations seemed to be induced by the graft and they inherited steadily. For understanding the possible mechanism of the phenomenon (graft_induced inheritable variation), we analyzed the cytoplasmic and genomic DNA of the variations. The results showed that there was no restriction fragment length polymorphism (RFLP) in the cytoplasmic DNA between the original scion and the variation. However, significant difference between the scion and variation was recognized by random amplified polymorphic DNA (RAPD) analysis. In addition, there was no evidence that indicated the gene transformation from stock to scion. Our results suggest that the non_specific grafting has a pragmatic potential for plant breeding and crop improvement and, the genetic variation seems not to be caused simply by DNA transformation but most likely the stress induced mutation.
文摘Molybdenum （Mo） and Cobalt （Co） play an important role in nitrogen （N） metabolism of grain legumes. Their applications to alkaline soils have been scarcely studied. A field experiment was set up to evaluate the Mo and Co application in common bean cv. Canario Centenario under two fertilization systems： inorganic fertilization and inoculation with Rhizobium etli. In each system, Mo and Mo ＋ Co were applied by seed impregnation at doses of 1.36 g/kg of seed for Mo and 0.26 g/kg of seed for Co; a control for each fertilization system and an absolute control were included. Yield components, nodules characteristics and N content by grains and foliage were evaluated. A completely randomized block design with seven treatments and five replications was used. Mo application increased the grain yield, grain size, nodulation and N accumulation in grains under both fertilization systems. Mo increased the total N uptake by the plant in 35.4% and 26%, for N fertilized and inoculated plants, respectively. Co application increased only nodules number and weight, and N content under inoculation. Mo application to beans cultivated in alkaline soils is recommended, but Co application is suitable only when beans are inoculated with rhizobia.
