EFFECT OF SALINITY AND DROUGHT STRESS ON GROWTH PARAMETERS, GLYCOSIDE CONTENT AND EXPRESSION LEVEL OF VITAL GENES IN STEVIOL GLYCOSIDES BIOSYNTHESIS PATHWAY OF Stevia rebaudiana (BERTONI)
Journal Title: International Journal of Genetics - Year 2015, Vol 7, Issue 1
Abstract
Stevia [Stevia rebuaidana (Bertoni)], a family of Asteraceae is known to yield diterpenoid steviol glycosides (SGs) that is about 300 times sweeter than sugar. The present work examined the effects of different concentrations (25, 50, 75 and 100mM) of NaCl and mannitol on growth, physiological response, glycosides content and expression profile of four genes in steviol glycosides biosynthesis pathway after 30 days of culture. The results showed that NaCl and mannitol significantly (p < 0.05) affect the no. of shoot, shoot length, root no. and root length. As NaCl and mannitol concentration increases leaf DW, stem DW, root DW, shoot DW and leaf FW were decreased markedly by 30-70 % and 50-55 %, respectively at 100mM. In addition, transcript expression profiling of genes involved in steviol glycoside biosynthesis pathway showed an increased in expression genes; KAH, UGT85C2, UGT74G1 and UGT76G1 in 50, 75 and 100mM NaCl concentrations compared with control. Interestingly, expression ratio of UGT76G1 (Rebaudioside A) was significantly increased by 67% as compared to UGT74G1 (Stevioside), showing that salinity stress plants are sweeter than normal plant, whereas all four genes were down-regulated in drought stress conditions. These results were compared with the steviol glycoside contents measured in the leaves that was quantified by HPLC. Results showed that amount of Rebaudioside A was significantly increased to 45.83, 63.32 and 80.21 mg g-1 at 50, 75 and 100mM NaCl condition whereas significant decrease was found in all treatment condition of mannitol. Present work thus suggests that NaCl is acting as an enhancer and manitol acting as a repressor of transcription to genes of steviol glycoside biosynthesis pathway that could alter the production of steviol glycosides.
Authors and Affiliations
M. PANDEY, S. K. CHIKARA
Keywords
Related Articles
- EP ID EP170113
- DOI -
- Views 75
- Downloads 0
COX-2 GENE POLYMORPHISMS: GENETIC DETERMINANTS OF CYSTIC FIBROSIS COMORBIDITIES
Cystic fibrosis (CF) has clinical variability associated with CFTR genetic mutations, environmental factors and modifier genes. Genes associated with the inflammatory process are important for understanding CF variabilit...
MOLECULAR GENETICS OF INTELLECTUAL DISABILITY WITH SPECIAL EMPHASIS ON THE IDIOPATHIC TYPE
Intellectual disability (ID), a phenomenon characterized by significantly subaverage intellectual functioning with deficits in adaptive behavior, such as daily-living skills, social skills and communication, is of common...
MOLECULAR GENETICS OF NON-SYNDROMIC CLEFTS REVISITED
Cleft of the lip and palate (CL/P) are generally divided in to two groups, isolated cleft palate and cleft with or without cleft palate representing a heterogeneous group of disorders affecting the upper lip and the roof...
ADRA2A IS A CYSTIC FIBROSIS MODIFIER GENE
Background: Cystic fibrosis (CF) is an autosomal disease with characteristics of a complex disease. Understanding ADRA2A polymorphisms are important to elucidate clinical variability that is encountered in inflammatory d...
HUMAN CHROMOSOMAL Q-HETEROCHROMATIN POLYMORPHISM AND ITS RELATION TO BODY HEAT CONDUCTIVITY
It is found that approximately 15-20% of non-coding part of human DNA is constitutive heterochromatin. There are two types of constitutive heterochromatin: C- and Q-heterochromatin. C-heterochromatin regions (C-HRs) are...