IFEVA   02662
INSTITUTO DE INVESTIGACIONES FISIOLOGICAS Y ECOLOGICAS VINCULADAS A LA AGRICULTURA
Unidad Ejecutora - UE
congresos y reuniones científicas
Título:
Pre-harvest sprouting in grain sorghum: Hormonal regulation of dormancy
Autor/es:
RODRÍGUEZ M.V.
Lugar:
´Chicago, Illinois, EEUU
Reunión:
Congreso; 64th Corn & Sorghum Seed Research Conference-Seed Expo 2009; 2009
Institución organizadora:
American Seed Trade Association (ASTA)
Resumen:
The problem: Some sorghum genotypes lose dormancy precociously and are susceptible to pre-harvest sprouting (PHS). Objective: To identify regulatory steps at the transcriptional level implicated in the expression of dormancy in sorghum grains. Objective: To identify regulatory steps at the transcriptional level implicated in the expression of dormancy in sorghum grains. Plant material: Two inbred lines with contrasting patterns of dormancy release (Fig. 1) and PHS behavior, IS9530 (PHS resistant) and RedlandB2 (PHS susceptible). Experiments: Expression of candidate genes (RT-QPCR) and hormone levels were studied in embryos dissected from grains after different incubation times. Background: Physiological evidence supports that the expression of dormancy in S.bicolor is controlled by the balance between two antagonistic hormones, abscisic acid (ABA, inhibits germination) and gibberellins (GA, promote germination). Results: Differentially regulated genes in both lines were identified as regulatory steps at the transcriptional level. è    In PHS resistant sorghum line IS9530, gene expression of several ABA signalling components is enhanced, while GA-inactivation genes GA levels are down-regulated and In PHS susceptible line RedlandB2, è    ABA signalling activity is low and GA levels are increased. è    GA inactivation gene (SbGA-2 oxidase C)