Abstract

Physiological disorders of Brassicas/Cole crops are abnormalities in leaf and stem morphology, colour, or both which are not caused by infectious diseases or insects. The abnormalities occur as a result of environmental stress, nutritional deficiencies or excesses on the plant. Reported causes of physiological disorders include genetic, environmental factors, nutrition, and cultural practices such as irrigation practices and tying leaves (blanching) for curd protection in cauliflower. Information was obtained  through review of existing literature and informal surveys in the four agro-ecological zones of Swaziland coupled with brief interviews of key farmers and producers of Brassicas. Physiological disorders encountered in this study included premature bolting of Brassica juncea, head splitting in head forming Brassicas, failure of or multiple head formation called blindness, riciness in cauliflower, oedema, internal tip burn, black petiole, pepper spot, vein streaking necrosis and necrotic spot in cabbage. Measures to alleviate these physiological disorders of Brassicas are suggested.

Key words: Physiological disorders, Brassicas/Cole crops, alleviating disorders, climate change.