Overexpression of BnKCS1-1, BnKCS1-2, and BnCER1-2 promotes cuticular wax production and increases drought tolerance in Brassica napus

In this study, orthologs of KCS1 and CER1 in Arabidopsis, designated BnKCS1-1, BnKCS1-2, and BnCER1-2, were isolated from Brassica napus. Transcription of BnKCS1-1 and BnKCS1-2 in B. napus were induced by abscisic acid (ABA) and drought treatment, while transcription of BnCER1-2 was induced only by drought treatment. All three gene transcripts decreased significantly when plants were treated with methyl jasmonate (MeJA) or subjected to cold stress. Overexpression of BnKCS1-1, BnKCS1-2, and BnCER1-2 under the control of the CaMV35S promoter led to a significant increase in cuticular wax on transgenic B. napus leaves. BnKCS1-1 and BnKCS1-2 overexpression led to similar differences from non-transformed plants, with significantly higher levels of aldehydes (C29 and C30), alkanes (C28, C29, and C31) and secondary alcohols (C28 and C29), and a significantly lower level of C29 ketone. Overexpression of BnCER1-2 led to an increase in alkanes (C27, C28, C29, and C31), a decrease in secondary alcohols (C28 and C29), and insignificant changes in other wax components. Scanning electron microscopy revealed that overexpression of BnKCS1-1, BnKCS1-2, and BnCER1-2 in B. napus resulted in a higher density of wax crystals on the leaf surface than observed in non-transformed plants. Transgenic plants showed a reduced rate of water loss and increased drought tolerance compared to non-transformed plants. These results suggest that BnKCS1-1, BnKCS1-2, and BnCER1-2 gene products can modify the cuti...
Source: The Crop Journal - Category: Food Science Source Type: research