An Inflorescence Disease of Amaranthus spp. in Nigeria Associated with Choanephora cucurbitarum

Symptoms of a devastating inflorescence disease of Amaranthus spp. associated with Choanephora cucurbitarum are described. It is characterized by extensive blighting of the inflorescence head and is often accompanied by inflorescence dieback and severe breaking of the floral head. In fields with severe infestation and under favourable conditions the inflorescence heads may be completely cut off. Such a plant will not produce any seeds or the yield may be reduced to half or less. Laboratory experiments confirm observations made in the field that the fungus is aggressively pathogenic on the apical region of the inflorescence. Usually, the green young inflorescences are more susceptible.