Nitrate affects sensu-stricto germination of after-ripened Sisymbrium officinale seeds by modifying expression of SoNCED5, SoCYP707A2 and SoGA3ox2 genes.
The influence of nitrate upon the germination of Sisymbrium officinale seeds is not entirely controlled by after-ripening (AR), a process clearly influenced by nitrate. Recently, we have reported that nitrate affects sensu-stricto germination of non-AR (AR0) seeds by modifying the expression of crucial genes involved in the metabolism of GA and ABA. In this study, we demonstrate that nitrate affects also the germination of AR seeds because: (i) the AR negatively alters the ABA sensitivity being the seed more ABA-sensible as the AR is farthest from optimal (AR0 and AR20 versus AR7); in the presence of diniconazole (DZ), a competitive inhibitor of ABA 8'-hydroxylase, testa rupture is affected while the endosperm rupture is not. (ii) AR7 seed-coat rupture is not inhibited by paclobutrazol (PBZ) suggesting that nitrate can act by a mechanism GA-independent. (iii) The germination process is accelerated by nitrate, most probably by the increase in the expression of SoNCED5, SoCYP707A2 and SoGA3ox2 genes. Taken together, these and previous results demonstrate that nitrate promotes germination of AR and non-AR seeds through transcriptional changes of different genes involved in ABA and GA metabolism.
Departamento de Fisiología Vegetal, Facultad de Farmacia, Universidad de Santiago de Compostela, 15782 Santiago de Compostela, Spain.
Néstor
N
Carrillo-Barral
Departamento de Fisiología Vegetal, Facultad de Farmacia, Universidad de Santiago de Compostela, 15782 Santiago de Compostela, Spain. Electronic address: angeljesus.matilla@usc.es.
Angel J
AJ
Matilla
Departamento de Fisiología Vegetal, Facultad de Farmacia, Universidad de Santiago de Compostela, 15782 Santiago de Compostela, Spain.
María del Carmen
Mdel C
Rodríguez-Gacio
Centro de Biotecnología y Genómica de Plantas (UPM-INIA), ETSI Agrónomos, Universidad Politécnica de Madrid, Campus de Montegancedo, 28223 Pozuelo de Alarcón, Madrid, Spain.
Raquel
R
Iglesias-Fernández
D019607:Brassicaceae / Q000502:physiology*; D003577:Cytochrome P-450 Enzyme System / Q000378:metabolism*; D049308:Dioxygenases / Q000378:metabolism*; D018506:Gene Expression Regulation, Plant; D018525:Germination; D006899:Mixed Function Oxygenases / Q000378:metabolism*; D009566:Nitrates / Q000378:metabolism*; D010940:Plant Proteins / Q000378:metabolism*; D012639:Seeds / Q000201:enzymology
D009566:Nitrates; D010940:Plant Proteins; D003577:Cytochrome P-450 Enzyme System; D006899:Mixed Function Oxygenases; D049308:Dioxygenases; C109043:9-cis-epoxy-carotenoid dioxygenase; C107203:abscisic acid 8'-hydroxylase; C108186:gibberellin 3beta-hydroxylase
After-ripening; Diniconazole; Hedge mustard; Nitrate; RT-qPCR analysis; Testa rupture