The Inheritance of Aliphatic Glucosinolates in Brassica napus

Abstract

The inheritance of aliphatic glucosinolates was studied in crosses between synthetic B. napus lines and oilseed rape cultivars. Six unlinked loci are described which determine the aliphatic glucosinolate profile of B. napus. One locus regulates the presence or absence of propyl glucosinolates, while another regulates the expression of pentyl glucosinolates. Two loci regulate the removal of the terminal H3CSgroup from the amino acid derivative to produce alkenyl glucosinolates as opposed to methylthioalkyl and methylsulphinylalkyl glucosinolates, regardless of the length of the alkyl chain. Likewise, another two loci regulate the hydroxylation of both butenyl and pentenyl glucosinolates. The functional alleles at one of the hydroxylation loci results in significantly more hydroxylation than those at the other locus. The large number of aliphatic glucosinolates which have been described in Brassica thus results from an interaction between genes which regulate side chain elongation and genes which modify the structure of the side chain, regardless of its length. The implications of this study for the biosynthesis of aliphatic glucosinoiates, the origin of B. napus and the potential to manipulate the leaf and seed glucosinolate profile of oilseed rape are discussed.

Genetics of aliphatic glucosinolates. III. Side chain structure of aliphatic glucosinolates in Arabidopsis thaliana

“…All plants were grown under standard conditions as described previously . Glucosinolates were extracted from freeze-dried leaf tissue, converted to desuiphoglucosinolates and analysed by HPLC as previously described (Magrath et aL, 1993). To investigate the production of hydroxypropyl glucosinolate, the segregation of glucosinolate profiles in recombinant inbred (RI) lines from a cross between Landsberg erecta, which has predominantly hydroxypropyl glucosinolate, and Columbia, which lacks this glucosinolate (Fig.…”

Divergent selection for secondary metabolites between wild populations of Brassica oleracea and its implications for plant-herbivore interactions

“…Several recent studies have begun to elucidate the genetic basis of biosynthesis of aliphatic glucosinolates (Magrath et al, 1993(Magrath et al, , 1994Parkin et a!., 1994;Mithen et al, 1995) and have shown that variation in side chain structure is under simple genetic control (Fig.1). Geographical and ecological variation in aliphatic glucosinolate composition has been described in Brassica (Mithen et al, 1987), Cakile edentula (Rodman, 1980), Arabidopsis thaliana (Bano, 1993;Mithen et al, 1995) and Cardamine cordifolia (Rodman & Chew, 1980 and seedlings are found in autumn (Mitchell & Richards, 1979).…”

Glucosinolates and disease resistance in oilseed rape (Brassica napus ssp. oleifera)

“…A 0 . 4 g sample of the ground pod tissue was used for glucosinolate extraction and analysis, with the same methods used for leaf glucosinolates as described by Magrath et al (1993).…”

“…After weighing, the bulk samples were immediately frozen under solid CO 2 , freeze dried and analysed for glucosinolates as described by Magrath et al (1993).…”