Since 2015, the stink locust (Zonocerus variegatus) population has been proliferating in the Mawanga sector, in the territory of Kasongo Lunda, an administrative entity in the province of Kwango in the Democratic Republic of Congo. This insect ravages food crops and fruit trees, devouring their leaves and bark and causing the host plant to wither. To assess the insecticidal action of four total extracts based on Nicotiana tabacum, Tephrosia vogelii, Zingiber officinale and Capsicum frutescens on the stink locust, a field trial involving a cassava crop was set up between November 2020 and December 2021 in the Emmaüs village in the Mawanga sector, Kasongo Lunda territory, in the Democratic Republic of Congo. Tobacco and ginger showed the lowest incidence and severity of locust damage. For the latter parameter, their performance was equal to that of deltamethrin. These two plant species showed potential for use in the manufacture of biopesticides to help farmers control the locust.
To evaluate the repellent or attractive properties of certain plant species to stink locusts, and to exploit them in the implementation of cropping systems likely to reduce the importance of the population of this pest and its damage on the cassava crop, a field experiment was carried out between November 2020 and December 2021. Living hedges consisting of Vernonia amygdalina, Melinis minutiflora, Cymbopogon citratus, Lantana camara and Euphorbia turicali were installed around the cassava plots. The living hedges with Vernonia amygdalina and Lantana camara acting as a trap crop gave low values for the number of insects on the cassava plots, incidence and severity of attacks compared to Euphorbia turicali, Melinis minutiflora and Cymbopogon citratus. The latter showed a phagorepellent effect as reflected by a higher number of stink locusts on cassava plots surrounded by living hedges made up of the above species. These five different species can therefore be used in the construction of integrated pest management systems to control locust damage to the cassava crop.
Show abstract
Full Text
