Study On Transformation Of Genes Related To Utilization Efficiency Of Potassium In Maize

Maize is one of the most important corps in China, which plays a crucial role in the national economy. With various applications, it is closed with us on every aspect of life. While the deficiency of potassium in cultivated soil and mineral resources in our country is so serious that it has become one of vital limiting factors in the maize production. Modifying and creating maize germplasm by molecular biology and genetic engineering to improve the absorption and utilization efficiency of potassium are important ways to solve this problem.In this study, three plant expression vectors were constructed based on pCAMBIA3300vector, with a maize ubiquitin promoter and three genes AtCBL9, AtAKT1and AIHAK1, which were related to utilization efficiency of potassium.Through Agrobacterium-mediated method, we transferred AtCBL9、AtAKTl and AIHAK1into somatic embryos of maize inbred line Y423respectively and successfully.25regenerated plants were obtained,13of which were verified to be transgenic plants after two rounds of PCR detection based on primers of BAR and the foreign genes. The detection rate was2.17%. We got7transgenic plants with AtCBL9,2with AtAKT1, and4with AIHAK1.By pollen tube pathway, the three genes were transferred into Z75and Z241, which were improved inbred lines of XianYu335’s parents PH6WC and PH4CV.30ears were transformed and4759To seeds generated. After Basta resistance screening and two rounds of PCR detection,78T0transgenic plants were obtained, including48plants with AtCBL9,13with AtAKT1and17with AlHAK1. The detection rate was1.22%. T1and T2plants were obtained by successive inbreeding. The same methods of screening and detection were used in the two generations to verify the transgenic plants.We detected AtAKT1in the T1and T2plants, and the detection rates were21.33%and37.33%. This result showed that the gene separated in the two generations and transgenic homozygous lines could be got from the successive inbreeding progenies.We analyzed T2transgenic plants with AtAKT1by PCR-southern blot, and the result indicated that the foreign gene had been integrated into the maize genome. The experiments of hydroponic culture illustrated that the transformation of AtAKTl improved transgenic plants’capacity of tolerance to low potassium stress to a certain extent.