Abstract:
Cuttings from plants of the same height of the Ghanaian Cassava cultivar, Ankrah, were planted into three soil volumes:
large (40 cm2 x 40 cm), medium (40 cm2 x 20 cm) and small (40 cm2 x 10 cm).
All plants from which cuttings were taken showed severe symptoms of Cassava mosaic virus disease (CMVD). Tuber (sink) size was directly related to soil volume, and so were growth as indicated by stem elongation, increase in leaf number and severity of CMVD symptoms, i.e. the larger the volume of soil and hence tuber size, the severer the expression of the disease.
Possible physiological reasons for this apparantly anomalous association of high tuber yields with severe disease symptoms are given.
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