This study aims to trace the situation of land use from 2005 to 2020 and its future at the end of this period to identify changes likely to establish a co-evolution between the state of ecosystems and the proliferation of stinking locusts. To achieve this, Landsat 7 and 8 images from 2005, 2010, 2015 and 2020 were uploaded to the US Geological Survey website platform: https://earthexplorer.usgs.gov. A classification was carried out using the ENVI software and the results were exported to ArcGIS for the editing and production of maps. During the 15-year period studied, forest cover decreased by 202.5 km2. As for the grassy and shrub savannah, they increased by 194.4 and 32.8 km2 respectively. The recorded decrease in forest in favor of an increase in grassy and shrub savannah in the Mawanga sector during the 15 years under study can explain the proliferation of stinking locusts infesting cassava cultivation. The increase in the area of ​​grassy savannah and the decrease in that of forest present favorable conditions for the proliferation of stinking locusts. Despite the increase in the area of ​​shrub savannah, this situation masks the degradation of this ecosystem favoring low humidity conducive to the multiplication of the stinking locust.

This research aims to identify changes in climatic factors likely to explain the proliferation of Zonocerus variegatus populations observed in the Mawanga sector since 2015. Data series of temperature, precipitation and relative humidity covering the period from 1985 to 2021 have been downloaded from the «power.larc.nasa.gov» website. They made it possible to calculate the Lamb or Nicholson index and to evaluate the variability in order to discriminate between years with precipitation, temperature and hygrometry deficiency from those in excess compared to normal. This diachronic analysis revealed a variability likely to impact the population dynamics of stinking locusts and increase their ravages against cassava cultivation. Associated with the phenological stages of the stinking locust, the variability of precipitation, temperature and relative humidity parameters recorded between 1985 and 2021 favored the proliferation of stinking locusts and subsequent attacks.

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.