Volume 47, Issue 1, November 2025, Pages 40–49
Sekpa Charles DEKOULA1, Malanno KOUAKOU2, Pitou Woklin Euloge Koné3, Gouzou Juste Roland DIDI4, Guy Fernand YAO5, Kouame Brou6, and Ochou Germain OCHOU7
1 Central Laboratory, Soils, Water and Plants (LCSEP), National Center for Agronomic Research (CNRA), 01 BP 633 Bouaké 01, Côte d’Ivoire
2 Laboratory of Agricultural Entomology, National Center for Agricultural Research (CNRA), Côte d’Ivoire
3 Département Agronomie et Foresterie, UFR Ingénierie Agronomique Forestière et Environnementale, Université de Man, BP 20 Man, Côte d’Ivoire
4 Plant Physiology Laboratory, Felix Houphouet- Boigny (UFHB), Côte d’Ivoire
5 Laboratoire de Pédologie et de Géologie Appliquée, Université Félix Houphouët-Boigny, Abidjan, Côte d'Ivoire
6 Centre National de Recherche Agronomique (CNRA), Km 17 Route de Dabou, 01 BP 1740 Abidjan 01, Côte d'Ivoire
7 Laboratory of Agricultural Entomology, National Center for Agricultural Research (CNRA), Côte d’Ivoire
Original language: English
Copyright © 2025 ISSR Journals. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
Cotton yield decrease in Côte d’Ivoire are important because of the climate change and pest infestations. The target of this survey is to analyze the spatio-temporal dynamics of Intra-Seasonal Descriptors (ISD) of rainfall and the annual mean infestation levels (MILs) of two pests, Helicoverpa armigera and Jacobiella facialis, as well as their interactions. The analysis datas are mainly constituted of annual rainfall and entomological data of H. armigera and J. facialis covering the period 1971-2016. The spatio-temporal distributions of rainfall ISDs and pest MILs were statistically analyzed, mapped, and their interactions determined using Instat+ and Surfer 11 software. Outcomes showed an interannual variability in rainfall ISDs, with coefficients of variation exceeding 30%. For H. armigera, MIL peaks shifted from the South and Center (1995–2000) to the Center-East and North-East (2011–2016), with an overall declining trend in MILs, attributable to the adoption of the Insecticide Resistance Management Program (IRMP) in 1999. However, a recent increase in peak levels suggests that climatic conditions particularly reduced cumulative rainfall and fewer rainy days favor its development. Regarding J. facialis, MILs increased from 3 to 16 infested plants per 30 plants, due to the IRMP’s limited focus on this pest, with the infestation hotspot shifting from the North (1995-2000) to the North-East and Center-East (2011-2016). These results demonstrated the relevance of integrating climatic conditions into pest management strategies.
Author Keywords: Cotton, rainfall descriptors, variability, pests, Côte d’Ivoire.
Sekpa Charles DEKOULA1, Malanno KOUAKOU2, Pitou Woklin Euloge Koné3, Gouzou Juste Roland DIDI4, Guy Fernand YAO5, Kouame Brou6, and Ochou Germain OCHOU7
1 Central Laboratory, Soils, Water and Plants (LCSEP), National Center for Agronomic Research (CNRA), 01 BP 633 Bouaké 01, Côte d’Ivoire
2 Laboratory of Agricultural Entomology, National Center for Agricultural Research (CNRA), Côte d’Ivoire
3 Département Agronomie et Foresterie, UFR Ingénierie Agronomique Forestière et Environnementale, Université de Man, BP 20 Man, Côte d’Ivoire
4 Plant Physiology Laboratory, Felix Houphouet- Boigny (UFHB), Côte d’Ivoire
5 Laboratoire de Pédologie et de Géologie Appliquée, Université Félix Houphouët-Boigny, Abidjan, Côte d'Ivoire
6 Centre National de Recherche Agronomique (CNRA), Km 17 Route de Dabou, 01 BP 1740 Abidjan 01, Côte d'Ivoire
7 Laboratory of Agricultural Entomology, National Center for Agricultural Research (CNRA), Côte d’Ivoire
Original language: English
Copyright © 2025 ISSR Journals. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
Abstract
Cotton yield decrease in Côte d’Ivoire are important because of the climate change and pest infestations. The target of this survey is to analyze the spatio-temporal dynamics of Intra-Seasonal Descriptors (ISD) of rainfall and the annual mean infestation levels (MILs) of two pests, Helicoverpa armigera and Jacobiella facialis, as well as their interactions. The analysis datas are mainly constituted of annual rainfall and entomological data of H. armigera and J. facialis covering the period 1971-2016. The spatio-temporal distributions of rainfall ISDs and pest MILs were statistically analyzed, mapped, and their interactions determined using Instat+ and Surfer 11 software. Outcomes showed an interannual variability in rainfall ISDs, with coefficients of variation exceeding 30%. For H. armigera, MIL peaks shifted from the South and Center (1995–2000) to the Center-East and North-East (2011–2016), with an overall declining trend in MILs, attributable to the adoption of the Insecticide Resistance Management Program (IRMP) in 1999. However, a recent increase in peak levels suggests that climatic conditions particularly reduced cumulative rainfall and fewer rainy days favor its development. Regarding J. facialis, MILs increased from 3 to 16 infested plants per 30 plants, due to the IRMP’s limited focus on this pest, with the infestation hotspot shifting from the North (1995-2000) to the North-East and Center-East (2011-2016). These results demonstrated the relevance of integrating climatic conditions into pest management strategies.
Author Keywords: Cotton, rainfall descriptors, variability, pests, Côte d’Ivoire.
How to Cite this Article
Sekpa Charles DEKOULA, Malanno KOUAKOU, Pitou Woklin Euloge Koné, Gouzou Juste Roland DIDI, Guy Fernand YAO, Kouame Brou, and Ochou Germain OCHOU, “Interannual variability of intra-seasonal rainfall descriptors and drawbacks on the spatio-temporal dynamics of Helicoverpa armigera and Jacobiella facialis infestations on cotton in Côte d’Ivoire,” International Journal of Innovation and Applied Studies, vol. 47, no. 1, pp. 40–49, November 2025.
