A Groundnut Wilt Disease on the Coast of Kenya

Abstract

TIn 1931 several varieties were obtained and planted in observation plots. Germination was satisfactory and good growth was made in the early stages. Soon after flowering began it was noted that some plants were wilting and dying off, And it quickly became apparent that this wilting would be the cause of serious loss. It appeared in all the plots and by the end of the season only one variety retained any healthy plants at all. This variety, a creeping type from Nyanza, lost only some 60 per cent of its population, the remainder ripening off normally. WILT DISEASE Specimens of wilted plants were sent to the Senior Plant Pathologist for examination, and he reported that the wilt was associated with Fusarium sp. Characteristically, the first signs of disease in the field are the yellowing of the outer leaflets. In the next stage, the leaflets close together and collapse. The plant may then die off rapidly and completely; sometimes, after shedding much of its foliage near the crown, it may partially recover and set a small crop. This is more likely to occur on plants wilting late in the season, and almost certainly depends to some extent on climatic conditions. If a diseased plant is lifted, the taproot will be found to show signs of rotting. It may be noted that once the disease had been recognized, local inquiries confirmed its presence in native gardens, and it became clear that this was the limiting factor in the development of groundnut cultivation in the coastal area