Differential expression of genes related to flue-cured leaf metabolism and response to climate by tobacco varieties at fast growing stage in Bijie

To investigate the effects of different tobacco varieties and climate on the expression of genes in pigment, nitrogen, starch and sugar metabolism pathway of flue-cured tobacco at mature stage, RT-PCR was used to analyze the gene expression in tobacco leaves of cv. Bina 1 and Jiucaiping 2 planted in Bijie(Guizhou) and Baofeng (Henan). The results showed that the expression levels of zeta-carotene desaturase (ZDS), chlorophyllase (CLH), glutamine synthetase (Gln1-3), nitrite reductase 3 (Nir-3), hexokinase (Hex), sucrose-6-phosphate phosphatase(SPP2)and trehalose-phosphate phosphatase(TPP)in Jiucaiping 2 planted in Bijie were higher than those in Bina 1 planted in Bijie. The results suggested that there were differences in metabolism pathway between Bina 1 and Jiucaiping 2. Nir-3 and cellulose synthase-like protein (CslE) gene expression in Bina 1 planted in Bijie expressed at a lower level and a higher level than those planted in Baofeng, respectively. The expression levels of Hex in Bina 1 and Jiucaiping 2 planted in Baofeng were higher than those planted in Bijie, and the expression of TPP in Jiucaiping 2 was lower than that planted in Bijie. This study indicated that these four genes(Nir-3, CslE, Hex and TPP) were affected mostly by climatic conditions.