MUTANT RHT-1 ALTERED FUNCTION ALLELES INFLUENCE THE RESPONSE OF WHEAT PLANTS TO K+ DEPRIVATION

MORICONI J I; BUET A; SIMONTACCHI M; SANTA-MARÍA GE

Potrero de los Funes, San Luis

Congreso; 47 Annual Meeting Argentine Society for Biochemistry and Molecular Biology; 2011

Sociedad Argentina de Investigación en Bioquímica y Biología Molecular

Near isogenic wheat lines carrying mutant alleles Rht-1 genes exhibit differential responses to K+ deprivation. J.I. Moriconi1, A. Buet2, M. Simontacchi2, G.E. Santa-María1 1- IIB-INTECH CONICET-UNSAM //2- INFIVE CONICET-UNLP. Potassium (K+) is an essential nutrient for plant growth and development. The way by which plants restrict their growth under K+ deprivation conditions is not well understood. In bread wheat (Triticum aestivum), DELLA proteins are encoded by the Rht-B and Rht-D genes: the allelic variants Rht-Ba/Rht-Da, determine a wild type (WT) phenotype, while the presence of the altered functions Rht-B1b /Rht-D1b alleles determine a double dwarf phenotype (DD). In this work, we evaluated the role of those different versions in the acclimationof plants to K+ deprivation. Experiments were conducted with two set of near isogenic lines (NILs) of Maringa and April Bearded cultivars. DD plants of both cultivars displayed no senescent response, while chlorophyll content of WT plants sharply declined, over a 16 day K+-deprivation period. In Maringa this difference exerted a positive impact on plant growth, while no differences in the relative biomass accumulation between NILs were observed in April Bearded.  We not observed differential effect in oxidative indicators, the presence of DD alleles ?in both cultivars- induced a major change in the antioxidant response, particularly SOD activity, as well as changes in the ionic composition (K+, Na+, Ca2+) under K+-deprivation conditions. Our data indicate that the acclimation response was influenced, at least in part, for the presence of altered function alleles in plant in wheat plants K+-deprived.