GLUCOSINOLATE CONTENT OF DEVELOPING RAPESEED (Brassica napus L. ’Midas’) SEEDLINGS

Abstract

The content of aliphatic, aromatic and indole glucosinolates were measured in the roots, hypocotyl, cotyledons and leaves of the high glucosinolate Brassica napus cultivar Midas over the first 10–14 d after seeding. For seedlings grown in light from emergence, glucosinolate content declined slightly then increased. Increase in the indole glucosinolate content of the shoot (hypocotyl and cotyledons) was caused by an increase in 3-indolylmethyl glucosinolate. When seedlings were confined to darkness for either 6 or 10 d after seeding, 3-indolylmethyl glucosinolate did not increase. The content of 4-hydroxy-3-indolylmethyl the dominant glucosinolate in the seed, declined in both light and dark grown seedlings. The individual glucosinolates in different parts of the seedling appeared to vary independently and to be related to development of specific organs or tissues. The complexity and relative rapidity with which amounts of the individual glucosinolates changed suggests the existence of an intricate metabolic control.Key words: Rapeseed, Brassica napus L., Cruciferae, glucosinolate, seedling development