Further studies on the metabolism of gibberellins (GAs) A9, A20and A29in immature seeds ofPisum sativumcv. progress No. 9

✍ Scribed by Valerie M. Sponsel; J. MacMillan

• Publisher: Springer-Verlag
• Year: 1977
• Tongue: English
• Weight: 746 KB
• Volume: 135
• Category: Article
• ISSN: 0032-0935
• DOI: 10.1007/bf00387161

✦ Synopsis

Seed maturation of Pisum sativum cv. Progress No. 9 proceeds more slowly in winter than in summer even when the parent plants are grown in greenhouse conditions with light-and heat-supplementation. For parent plants grown under "summer" and "winter" conditions the metabolism of [3H]GA9 in cultured seeds is qualitatively different in seeds of equivalent age and qualitatively the same in seeds of equivalent weight.

13-Hydroxylation of [3H]GA9--+[3H]GA20 is restricted to early stages of seed development. 2fl-Hydroxylation of [ 3 H]GA 9 --+ 2fl-OH-[3H]GA9 has only been observed at a stage of development after endogenous GA9 has accumulated. 2fi-OH-GA9 has been shown to be endogenous to pea and is named GAs1. H2-GA31 and its conjugate have not been shown to be present in pea and may be induced metabolites of [3H]GA9. The metabolism of GA20-->GA29 is used to illustrate a technique of feeding [2H][3H]GAs in order to distinguish a metabolite from the same endogenous compound. The in vitro conversion of [3H]GA20--+[3H]GA29, and the virtual non-metabolism of [3H]GA29 have been confirmed for seeds in intact fruits. These results are discussed in relation to the apparent absence of conjugated GAs in mature pea seeds.