Glucosinolates and Resistance to Leptosphaeria maculans in Wild and Cultivated Brassica Species

Abstract

Synthetic lines of Brassica napus were derived by combining the genomes of B. atlantica and B. oleracea var. alboglabra, which were respectively resistant and susceptible to foliar infection by Leptosphaeria maculans, with a susceptible line of B. rapa. Resistance was expressed in the synthetic lines containing the genome of B. atlantica. The high levels of alkenyl glucosinolates which occur in leaves of B. atlantica, and which have been implicated in disease resistance, were also expressed within the synthetic lines, although the dominant glucosinolate had changed from sinigrin to glucobrassicanapin. Disease resistance and glucosinolate profiles did not co-segregate in F2 progeny from crosses between the synthetic lines.

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

“…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). Casual observation suggests that seedling establishment is a rare event, although no detailed data are available.…”

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

“…Several studies have shown that wild Brassica species have very high levels of leaf glucosinolates in contrast to the low levels found in B. napus. To enhance the levels in B. napus (an amphidiploid species, genome AACC, 2n ¼ 38), a wild form of B. oleracea (CC, 2n ¼ 18) from Tunisia was crossed with a wild form of B. rapa (AA, 2n ¼ 20) from Sicily and, following in vitro embryo rescue, a synthetic form of B. napus was developed, as described by Mithen & Magrath (1992). This line was crossed to the oilseed rape cultivar Cobra, and the F 1 hybrid backcrossed to Cobra.…”

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

“…The biological activity of glucosinolates is largely dependent on the structure of the side chain which determines the nature of hydrolysis products which are produced following tissue damage. Intraspecific variation in the types of aliphatic glucosinolates has been shown to occur in Cakile edentula (Rodman, 1980), Brassica oleracea (sensu lato) (Mithen et at., 1987) and Arabidopsis thaliana (Bano, 1993).…”