Fallah F, Nokhasi F, Ghaheri M, Kahrizi D, Beheshti Ale Agha A, Ghorbani T, Kazemi E, Ansarypour Z
Department of Agronomy and Plant Breeding, Razi University, Kermanshah, Iran.
Department of Medicinal Plants, Institute of Higher Education, Jahad-e-Daneshgahi, Kermanshah Unit, Iran.
Cell Mol Biol (Noisy-le-grand). 2017 Aug 15;63(7):102-106. doi: 10.14715/cmb/2017.63.7.17.
Stevia rebaudiana Bertoni is a famous medicinal plant for its low calorific value compounds which are named steviol glycosides (SGs) and they are 150-300 times sweeter than sugar. Among various SGs, stevioside and rebaudioside A considered to be the main sweetening compounds. Soil salinity is one of the most essential stress in the world. Salinity affects the survival and yield of crops. In current study the effects of salinity and osmotic stress caused by different concentration of NaCl (0, 20, 40, 60 and 80 mM) on morphological traits, genes expressionand amount of both stevioside and rebaudioside Aunder in vitro conditions has been investigated. The morphological traits such as bud numbers, root numbers, shoot length (after 15 and 30 days) were evaluated. With increasing salinity, the values of all studied morphological traits decreased. To investigation of UGT74G1 and UGT76G1 genes expression that are involved in the synthesis of SGs, RT-PCR was done and there were significant differences between all media. The highest expression of both genes was observed in plantlets grown on MS media (with NaCl-free). Also, the lowest amounts of gene expression of the both genes were seen in MS+ 60 mM NaCl. Based on HPLC results, the highest amount of both stevioside and rebaudioside A were observed in plantlets grown in MS media (with NaCl-free). Finally, it can be concluded that stevia can survive under salt stress, but it has the best performance in the lower salinity.
甜叶菊是一种著名的药用植物，因其含有低热量化合物甜菊糖苷（SGs），其甜度是蔗糖的150 - 300倍。在各种甜菊糖苷中，甜菊糖苷和莱鲍迪苷A被认为是主要的甜味化合物。土壤盐渍化是世界上最重要的胁迫之一。盐渍化影响作物的存活和产量。在当前研究中，研究了不同浓度NaCl（0、20、40、60和80 mM）引起的盐胁迫和渗透胁迫对离体条件下甜叶菊形态特征、基因表达以及甜菊糖苷和莱鲍迪苷A含量的影响。评估了芽数、根数、茎长（15天和30天后）等形态特征。随着盐度增加，所有研究的形态特征值均下降。为了研究参与甜菊糖苷合成的UGT74G1和UGT76G1基因的表达，进行了RT-PCR，所有培养基之间存在显著差异。在无NaCl的MS培养基上生长的幼苗中观察到这两个基因的最高表达。此外，在MS + 60 mM NaCl中观察到这两个基因的最低表达量。基于HPLC结果，在无NaCl的MS培养基上生长的幼苗中观察到甜菊糖苷和莱鲍迪苷A的最高含量。最后，可以得出结论，甜叶菊可以在盐胁迫下存活，但在低盐度下表现最佳。
