Glucosinolate allocation patterns in oilseed Brassica carinata

Abstract

The introduction of oilseed Brassica carinata (carinata) into the southeastern US cropping system has fueled its
prospects as a sustainable source of biojet fuel for the aviation industry. The presence of sulfur-rich defensive compounds
called glucosinolates (GSLs) are effective against herbivores and soil-borne pathogens and understanding what biotic
and abiotic factors trigger GSL synthesis and accumulation is important in the management of Total Glucosinolate
Content (TGC) in various plant parts of carinata. In this study, we investigated the accumulation of TGC in B. carinata
cv. AAC A110 in various plant tissues, throughout the plant life-cycle, and in soil types with differing land management
practices. We found that B. carinata has greater biomass accumulation and root TGC when grown in soil with high
organic matter compared to soil derived from areas of intensive or conventional farming (CF) or sand without affecting
seed yield. Leaf TGC decreased during the transition from vegetative to reproductive growth indicating that it may be the
primary source of GSLs, which are translocated to the developing seeds until physiological maturity. Our results
demonstrate the GSL allocation patterns of carinata are like those proposed by the optimal defense theory and could be
an important trait for crop defense and future production in the region.