Host plants of Stictococcus vayssierei Richard (Stictococcidae) in non-crop vegetation in the Congo basin and implications for developing scale management options.
Surveys were carried out in five vegetation types to identify, in non-crop vegetation, host plants of Stictococcus vayssierei Richard, a pest of cassava in the Congo basin. Along transects within each of these vegetation types, all plants with underground storage structures and including those belonging to the plant families known to be used by S. vayssierei were uprooted and inspected for the presence of the scale. Sixteen plant species belonging to 13 families were identified as hosts of S. vayssierei. Eleven out of the host species are indigenous and 13 are newly identified hosts for S. vayssierei. Six new host families were identified. Infestation levels and the distribution of S. vayssierei indicated that native Dioscorea species may play an important role in the maintenance of the scale in long fallows and in secondary and primary forests, while exotic plants such as cassava may contribute to S. vayssierei population growth in fallows less than eight years old. Our findings suggest that destruction and removal of S. vayssierei host plants from non-crop vegetation might be useful in reducing S. vayssierei infestations and improving cassava yields.