Seasonal patterns of Zonocerus variegatus developmental stages in Kisangani, Democratic Republic of the Congo, Democratic Republic of the Congo
DOI:
https://doi.org/10.51867/ajernet.7.2.115Keywords:
Climatic Drivers, Democratic Republic of the Congo, Population Dynamics, Seasonal Phenology, Tropical Agroecosystems, Zonocerus variegatusAbstract
Zonocerus variegatus is an important pest in tropical agroecosystems, but its seasonal population dynamics remain poorly documented in the Kisangani region of the Democratic Republic of the Congo. This study used a quantitative, longitudinal observational design based on repeated monthly field surveys. This study examined monthly changes in the developmental stages of the species in two localities within the humid forest zone. It also assessed how temperature, rainfall, and relative humidity were related to fluctuations in post-embryonic stages. Specimens were classified into developmental stages using morphological criteria, and monthly counts were summarized over two annual cycles. Relative abundances were calculated by developmental stage, month, and year. The relationships between developmental-stage structure and climatic variables were analysed using redundancy analysis, after standardizing temperature, rainfall, and relative humidity. Pairwise correlations were also used to examine direct associations between developmental stages and climatic variables, while graphs were produced to show monthly and annual patterns. The results showed clear seasonal variation. Juveniles were dominant at the beginning and end of each annual cycle, whereas adults were more abundant between June and September. Pseudo-nymphs remained rare throughout the year. Ordination and correlation analyses indicated that climatic conditions were associated with changes in developmental-stage structure, although their explanatory power was limited. These findings suggest that the phenology of Z. variegatus in Kisangani is seasonally structured and is probably influenced by both climatic and ecological factors. From a management perspective, the high abundance of juveniles indicates that control measures should preferably target early developmental stages during seasonal peaks. Future studies should also consider host-plant availability, natural enemies, and habitat characteristics to improve prediction and management strategies.
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Copyright (c) 2026 Toengaho Sembaito Alfred, Danadu Mizani Célestin, Mubenga Kankonda Onésime, Kosele Kada Jonathan, Ngabu Chembu Jean, Tambwe Lukosha Ernest, Kankonda Busanga Alidor
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