GLUCOSINOLATE CONTENT IN INTERSPECIFIC CROSSES OF BRASSICA-CARINATA WITH BRASSICA-JUNCEA AND BRASSICA-NAPUS

Brassica carinata A. Braun is a highly productive oilseed crop in the Ethiopian highlands, but the seed has a high 2-propenyl glucosinolate content, which is undesirable. The objective of this study was to intr ogress, through interspecific crosses, genes for low 2-propenyl glucos inolate content from the B genome of B. juncea and C genome of B. napu s into the B. carinata B and C genomes and thus develop low glucosinol ate B, carinata. The cross [(B. carinata x B, juncea)x B. carinata] yi elded plants that contained only approximate to 20 mu moles of 2-prope nyl glucosinolate, which was an 85% reduction compared with levels in B. carinata seed. Plants of the [(B, carinata x B, napus) x B. carinat a] cross had normal high concentrations of 2-propenyl glucosinolate. B ackcross plants of both interspecific crosses also contained 3-butenyl and 2-hydroxy-3-butenyl glucosinolates. The results of these crosses suggested that genes for glucosinolate synthesis were located on B gen ome chromosomes of B. carinata because B. napus C genome introgression s did not result in reductions of total glucosinolate contents. The to tal alkenyl glucosinolate content of one F-3 family of the B. juncea b ackcross was similar to that of the B, juncea parent. It was concluded that through further selection in this family, B. carinata plants cou ld be identified that would be basically free of 2-propenyl glucosinol ate, and have a low total alkenyl glucosinolate content.