低钾胁迫下高钾烤烟苗期根系差异表达蛋白分析

为了解高钾烤烟苗期根系在低钾胁迫下的差异表达蛋白及其作用机理,本研究分别提取低钾和正常钾营养液培育的高钾烤烟品系HKDN-5的苗期根系蛋白,酶解后采用液相色谱串联质谱和label-free蛋白定量技术对差异表达蛋白进行鉴定分析。结果表明,与正常钾相比,低钾组共发现681个差异表达蛋白,其中有359个发生下调表达,322个上调表达。差异表达蛋白主要参与脂质代谢、次生代谢、碳水化合物代谢和遗传信息加工等途径。其中,下调蛋白具有翻译后修饰、蛋白质转换、伴侣蛋白相关功能的数量最多,上调蛋白主要为一般功能相关蛋白。差异倍数较大的蛋白主要与代谢和应激反应过程相关。以上结果表明,低钾胁迫产生的差异蛋白主要参与物质代谢及应激反应等相关过程。

Analysis of F_1 Heterosis of Potassium Content on Self-bred High-potassium New Strains of Flue-cured Tobacco

F1 potassium heterosis of 8 flue-cured tobacco varieties and 6 self-bred high-potassium new strains were studied. The results showed that the F1 mean het- erosis of potassium content had differences between different parts of plants, showing B2F （8.45%）〉X2F （7.59%）〉C3F （5.64%）; the F1 over-parent heterosis of potassium content of various parts was not obvious, showing X2F （0.05%）〉C3F （-0.43%） 〉B2F （-0.48%）; the F, control heterosis of potassium content of different parts showed B2F （17.81%）〉X2F （4.06%）〉C3F （1.12%）. The variance of GCA of potassium content in various parts of the 6 self-bred high-potassium new strains was significant or extremely significant, and all leaves of GK2 had greater GCA effect on potassium content; C3F and X2F of GK7 had good GCA effect on potassium con- tent, but GCA effect was bad in B2F; GK9 preformed well in B2F but badly in C3F. The variance of SCA in all combinations was extremely significant, and the good combinations included Duoye 87xGK7 （17.19%） in B2F, Duoye 87xGK2 （25.63%）, ChangbohuangxGK5 （19.43%）, Yunyan 87xGK7 （22.78%）, and Yunyan 87xGK9 （24.38%） in C3F, Coker176xGK7 （19.87%）, 101xGK9 （15.89%）, Yunyan 85xGK9 （19.15%）, and Yunyan 87xGK9 （20.74%） in X2F.

Analysis of F_1 Heterosis of Agronomic Traits and Chemical Components on Selfbred Highpotassium New Lines

F1 heterosis of agronomic characters and chemical components of 8 fluecured tobacco varieties and 6 self-bred high-potassium new lines was studied. The results showed that 4-5 weeks after transplanting was the main changing period of agronomic traits. Compared with the comparative heterosis, among the proportions of combinations showing positive comparative heterosis at the significant level, the heterosis proportions of plant height （97.92%）, internode length （100%） and stem girth （58.33%） were larger, these of total nitrogen （83.33%）, protein （79.17%）, nicotine （79.17%） and potassium （95.83%） in upper leaves were larger, these of total sugar （64.58%）, total nitrogen （68.75%）, protein （72.92%） and nicotine （64.58%） in middle leaves were larger, and in lower leaves, except that the proportion of chlorine was smaller （12.50%）, the proportions of other chemical components all exceeded 40%. Compared with average heterosis, among the proportions of combinations showing positive comparative heterosis at the significant level, the heterosis proportions of plant height （54.17%）, leaf width （43.75%）, stem girth （43.75%） and internode length （72.92%） were larger, these of total sugar （47.92%） and reducing sugar （54.17%） in upper leaves were larger, these of all the chemical components in middle leaves exceeded 30%, and these of all the chemical components in lower leaves were in the range of 27.08%-41.67%. Compared with heterobeltiosis, among the proportions of combinations showing positive comparative heterosis at the significant level, that of the internode length （60.42%） was larger, these of chemical components in upper leaves were in the range of 8.33%-29.17%, these of chemical components in middle leaves were in the range of 20.83%-39.58%, and these of chemical components in lower leaves were in the range of 16.67%-35.42%. It was indicated that rational effective control of water and fertilizer in this sensitive period could significantly enhance heterosis.