INVESTIGADORES
MORICONI Jorge Ignacio
congresos y reuniones científicas
Título:
ALTERED FUNCTION RHT ALLELES CONTRIBUTE TO ANTIOXIDANT RESPONSE DURING THE ACCLIMATION OF WHEAT PLANTS TO POTASSIUM DEFICIENCY
Autor/es:
MORICONI J.I.; BUET A; SIMONTACCHI M; SANTA-MARÍA GE
Lugar:
Sao PAulo
Reunión:
Congreso; Free Radicals in Brazil. VII Meeting of South American Group of the SFRBM.; 2011
Institución organizadora:
SFRBM
Resumen:
Altered
function Rht alleles contribute to antioxidant response during the acclimation
of wheat plants to potassium deficiency Moriconi JI1; Buet A2; Simontacchi M2; Santa-María
GE1 - 1CONICET - IIB-INTECH; 2CONICET - INFIVE-UNLP
Potassium (K+) has proved to be an
essential nutrient for plant growth and development. Understanding the
mechanisms involved in the growth restriction that takes place under K+-limiting
condition could help to find genotypes with improved K+ -use
efficiency, which is a major objective of plant breeders. However, 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 normal phenotype, while
the presence of the altered functions Rht-B1b /Rht-D1b alleles
reduce plant height. The aim of this study was to evaluate the role of those
different versions in the acclimation of plants to K+ deprivation.
Experiments were conducted with two set of near isogenic lines (NILs) of
Maringa and April Bearded cultivars. Rht-B1b/Rht-D1b plants of both
cultivars displayed no senescent response, while chlorophyll content of Rht-B1a/Rht-D1a
plants sharply declined, over a 16 day K+-deprivation period. While
in Maringa this difference exerted a positive impact on plant growth, no
differences in the relative biomass accumulation between Rht-B1b/Rht-D1b
and Rht-B1a/Rht-D1a NILs were observed in April Bearded. While no differential
effect on protein carbonilation or lipid peroxidation was detected between
NILs, the presence of Rht-B1b/Rht-D1b 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 presence
of altered function alleles influences the acclimation response of wheat plants
to K+-deprivation at least in part through a modification of the
antioxidant response.
Agencia de Promoción Científica y Tecnológica PICT
2007-00481/PICT2008-1384