Study Of Tobacco Plastid Pigment Metabolism And Its Influencing Factors

In order to elucidate the effect of metabolism of plamochromic pigment ontobacco type, the flue-cured tobacco cultivar K326were grown in PingdingshanHenan, Yuxi Yunnan and Zunyi Guizhou, characteristics of burnt-sweetness,pure-sweetness and fresh-sweerness type, respectively. In the process of tobacco leafdevelopment, the ultrastructure and the main plamochromic pigment contents of themwere compared as well as the expression of several key genes related to metabolismof plamochromic pigment. At the same time, the effects of different light conditionson tobacco, the flue-cured tobacco cultivar Zhongyan100, plastid pigmentmetabolism were be discussed, and compared with each other on the ultrastructureand the main plamochromic pigment contents. The main results were listed asfellows:1. In three type tobacco planting zones, the change tendency of ultrastructure oftobacco leaves on K326existed significant difference. The chloroplast and thylakoidlamella of Henan tobacco leaves degraded most sufficiently. But Yunnan tobaccoleaves degraded most slowly. The structural changes of nucleus were similar to thechloroplast and thylakoid lamella in three type tobacco planting zones. The chemicalcomposition analysis showed that the plamochromic pigment content of Henantobacco leaves was the lowest, lower than the content of Yunnan tobacco. The geneexpression analysis indicated that the genes related to plamochromic pigment inYunnan tobacco leaves were relatively, which was conducive to accumulate moreplamochromic pigment. The content of Guizhou was higher than that in Henan,because expression of related genes in Guizhou was activer than than in Henan.2. Under different light conditions, the changes of ultrastructure of tobacco leavesexisted significant difference. The chloroplast and thylakoid lamella degraded lightunder high-level and middle-level light conditions, as well as the long periodtreatment. The structure under low-level high condition was normal. The chemical composition analysis showed that the plamochromic pigment content under blue andred light conditions was lower than white one. Low-level light could obviouslypromote plamochromic pigment content. The gene expression analysis indicated thatthe genes related to plamochromic pigment in Yunnan tobacco leaves were relatively,which was conducive to accumulate more plamochromic pigment, as well as UV-Btreatment did. The gene expression analysis indicated that Low-level light, shortperiod and UV-B could promote plamochromic pigment content.