A current appraisal of banana and plantain diseases in Malawi

Major banana and plantain production centres in Malawi were surveyed for diseases and soil-borne pests in June 1990. Fusarium wilt, which is also known as Panama disease (caused by Fusarlum oxysporum f. sp. cubense) caused considerable damage throughout the Karonga and Chitipa Districts of the Northern Region. The disease has been recognized in these areas since the early 1970s and probably was introduced into Malawi from southern Tanzania. The disease has eliminated the preferred banana cultivar, 'Bluggoe', in northern parts of the Karonga District, and at the time of the survey had begun damaging 'Pisang awak', the cultivar many producers have used to replace 'Bluggoe'. Fusarium wilt was also found for the first time in the Thyolo and Mulanje Districts of the Southern region on 'Bluggoe'. Black leaf streak (caused by Mycosphaerella fijiensis) was observed in the Nkhata Bay and Karonga Districts; it is reported for the first time in Malawi. The disease has been in the respective areas for 4 and <2 years, but significant damage was observed only in portions of the Nkhata Bay District; 'Dwarf Cavendish', 'Red', 'Green red', and several different plantain cultivars were badly affected. Environmental conditions are conducive to an increased severity of the disease in the Karonga and Nkhata Bay Districts in the near future. Cordana leafspot (caused by Cordana musae) and Sigatoka leafspot (caused by M. musicola) caused locally important, but less severe, damage in the country than did fusarium wilt and black leaf streak. Serious nematode infestations were observed only in the Southern Region where Radopholus similis caused rhizome necrosis and some toppling of 'Dwarf Cavendish' in the Thyolo District. The banana borer. Cosmopolites sordidus observed at low levels in the Karonga District, is reported for the first time in Malawi. Other diseases, nematodes and insect pests that were observed during the survey were not causing significant damage at the time of the survey.