Chemical composition and herbicidal potent of cauliflower (Brassica oleracea var. botrytis) and cabbage turnip (Brassica oleracea var. gongylodes). Saad, I., Rinez, I., Ghezal, N., and Haouala, R. (Tunisia)

Abstract

This study was conducted to evaluate the phytochemical content and allelopathic potential of two cabbages botanical varieties leaves, ie. cauliflower (Brassica oleracea var. botrytis) and cabbage turnip (B. oleracea var. gongylodes). Their aqueous and organic extracts were evaluated on lettuce (Lactuca sativa) and one of the most dominant weeds in Tunisia, nettle-leaf goosefoot (Chenopodium murale). Field experiments were conducted to evaluate the smothering potential of the two varieties. The total phenolics, flavonoïds, flavonols and flavones, alkaloïds, and proanthocyanidins contents were higher in the aqueous extracts of both varieties. For organic extracts, petroleum ether and methanol cauliflower extracts and chloroform and methanol cabbage turnip extracts were the richest ones. All aqueous and organic extracts had significantly delayed germination, reduced its rate and affected seedling growth. Reduction of germination and growth were more important using the higher concentrations and in presence of cabbage turnip extract. The organic extracts of both varieties had significantly inhibited the seedling growth of target species, especially petroleum ether, and methanol cauliflower extracts and chloroform and methanol cabbage turnip ones. Field experiment highlighted the smothering potential of the two varieties and confirmed the higher allelopathic potential of cabbage turnip as compared to cauliflower.

Keywords

• Cabbage turnip
• cauliflower
• Chenopodium murale
• growth
• phytochemical analysis
• smothering potential
• speed germination