Study On AtCIPK23Gene Enhancing The Tolerance Of Transgenic Potato Microtuberization To Low Potassium

Potato is a kind of potassium crop, and potassium fertilizer has important role on potato yield and quality. In our former study,we obtained transgenic potato lines with AtCIPK23gene. In order to explore characters transgenic potato tubers with AtCIPK23gene, we used several transgenic potato lines to get further research on AtCIPK23gene under low potassium condition. The W potato cultivar plants and transgenic potato lines LI, L23and L34under two microtuber induction treatment, we chose the better microtuber induction method system of transgenic potato with AtCIPK23gene. We determined the number, the diameter and the water content of microtuber of transgenic potato under two treated of different potassium concentration. Then the above materials under selected representative potassium concentration of microtuber induction, we determined the potato tubers and the plants potassium content in different periods of microtuber induction and the sucrose and the starch content in harvest time. Analysis of transgenic and non-transgenic potato in low potassium and normal potassium conditions, the results are as follows;Through the comparison of two kinds of microtuber induction method, the tuber number, the diameter and the water content were not significant in4lines under the first kind of microtuber induction treatment. Under the second kinds of microtuber induction treatment, the number, the diameter and the water content of tuber of transgenic lines LI, L23and L34were higer than that of Win different low potassium concentration. And the number, the diameter and the water content of tuber of transgenic lines L23and L34compared with non-transgenic line reached significant or extremely significant level in low potassium concentration. In normal potassium concentration of microtuber induction conditions, the number, the diameter and the water content of tuber of transgenic lines and non-transgenic lines were not significantly different. The tuber number, the diameter and the water content of4lines increased with potassium concentrations rose. The results showed that, the second kind of treatment is more applicable to study the effect of potassium on potato tuberization of transgenic potato. On transgenic potato with AtCIPK23gene physiological analysis shows, in low potassium concentrations, potassium content of transgenic lines of microtuber was higher than that of non-transgenic line of microtuber under tuber formation periods; in normal potassium concentration, there was no significant difference between different lines at different stages. Potassium content of tubers increased as potassium concentration rose at the different periods, reached maximum in normal potassium content. Among them, potassium content of microtuber of transgenic lines LI, L23and L34were significantly or very significantly higher than that of microtuber of non-transgenic line W under different potassium concentrations. In low potassium concentrations, potassium content of transgenic lines was higher than that of non-transgenic line under tuber formation period; in normal potassium concentration, there was no significant difference between different lines. Potassium content of lines decreased as potassium concentration down at the different stages, and potassium content of plantlets under normal potassium concentration were higher than under low potassium concentration.The sucrose and the starch content of microtuber of transgenic lines were higher than that of non-transgenic lines under low potassium concentration, but those were not significant difference between transgenic lines and non-transgenic lines under normal concentration. The experiment on transgenic potato lines with AtCIPK23gene under low potassium condition shows that, AtCIPK23gene improved the ability of microtuberation and the potassium content of tuber and plants under low potassium concentration. We speculated that high potassium content was raising the ability of sucrose transport and conversion of sucrose to starch of transgenic lines.