ISSN:
1432-2048
Schlagwort(e):
Embryo vigour
;
Germination (embryo)
;
Poly(A) RNA
;
Vigour (seed)
;
Triticum (seed vigour)
Quelle:
Springer Online Journal Archives 1860-2000
Thema:
Biologie
Notizen:
Abstract Polyadenylated-RNA (Poly(A)+RNA) levels have been studied during the germination of wheat embryos of high viability but differing vigour. In high-vigour embryos imbibed at 20°C the level of poly(A)+RNA falls dramatically over the first hour of imbibition, then remains constant up to 3 h of imbibition before increasing rapidly to a level similar to that found in the quiescent state by 7 h of imbibition. Median-vigour embryos imbibed at 20°C show similar changes in poly(A)+RNA content but the initial decrease and subsequent increase in poly(A)+RNA levels are less marked. On imbibition at 10°C, the poly(A)+RNA content in high-vigour embryos decreases to a lesser extent during the first hour than at 20°C and the level increases more slowly over the next 6 h than during the same time period at 20°C. The level of poly(A)+RNA in medianvigour embryos remains constant over the first 4 h of germination and then falls to a level of about half that found in quiescent high-vigour embryos. Polyacrylamide gel electrophoresis of total-RNA samples shows that the polyadenylic acid (poly(A)) sequences occur in RNA species ranging in size from 35-7S. Polyacrylamide gel electrophoresis of isolated poly(A) sequences demonstrates the presence of two size classes of poly(A) in quiescent embryos, but at 20°C a more heterodisperse pattern appears by 2 h of imbibition. At 10°C, two size classes of poly(A) persist throughout the period studied in both high- and median-vigour embryos, although in median-vigour embryos the ratio of larger: smaller poly(A)-tail sizes decreases more rapidly than in high-vigour embryos.
Materialart:
Digitale Medien
URL:
http://dx.doi.org/10.1007/BF00393312
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