Effect of Fertilizer Application on Mealybug Infestation and Physiological Responses of Cocoa at the CNRA Station, Divo, Côte d'Ivoire

Pierre Walet N’Guessan; Stanislas Kouakou Koffi; Diallo Karim Aboudou; Alain Acka Jacques Kotaix; Leonard Rusinamhodzi; Richard Asare; Kouassi Allou

doi:doi:10.11648/j.bio.20261405.12

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Effect of Fertilizer Application on Mealybug Infestation and Physiological Responses of Cocoa at the CNRA Station, Divo, Côte d'Ivoire

Pierre Walet N’Guessan^*

, Stanislas Kouakou Koffi, Diallo Karim Aboudou, Alain Acka Jacques Kotaix, Leonard Rusinamhodzi, Richard Asare, Kouassi Allou

Published in American Journal of Bioscience and Bioengineering (Volume 14, Issue 5)

Received: 28 September 2026 Accepted: 12 October 2026 Published: 29 October 2026

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Abstract

Applying fertilizer is one solution for improving cocoa production. However, while it improves cocoa productivity, it also promotes the development of pests and disease vectors. This study aimed to understand the effects of fertilizer on the proliferation of mealybugs known as vectors of cocoa swollen shoot virus. The experimental design was a Fisher block with four fertilizer formulations (T1 to T4) and an unfertilized control (T0), each replicated three times. Each elementary plot contained 45 cocoa trees from CNRA research station in Divo, Côte d’Ivoire. Mealybug infestation levels were evaluated every 15 days for one year, and three cocoa leaves were collected per treatment and replication in order to determine physiological and biochemical parameters. The data were analyzed using SAS 9.4 and XLSTAT 2025. The results revealed seven species of mealybugs in the treatments: Formicococcus njalensis, Planococcus citri, Ferrisia virgata, Pseudococcus longispinus, Phenacoccus hargreavesi, Dysmicoccus brevipes, and Planococcus kenyae. Furthermore, analysis of variance revealed significant differences among the treatments regarding the content of chlorophyll A and B, total chlorophyll, carotenoids, protein, phenolic compounds, and proline. However, among the seven mealybug species identified, principal component analysis revealed a link between Formicococcus njalensis, Ferrisia virgata, and Dysmicoccus brevipes, as well as chlorophyll A and B, total chlorophyll, carotenoids, protein, phenolic compounds, and total sugars, in T0, T3, and T4. Meanwhile, the mealybug species Pseudococcus longispinus and Phenacoccus hargreavesi were linked to proline in treatment T2. Overall, the study showed that fertilizer has a small impact on mealybug and more on the physiological and biochemical parameters.

Published in	American Journal of Bioscience and Bioengineering (Volume 14, Issue 5)
DOI	10.11648/j.bio.20261405.12
Page(s)	101-109
Creative Commons	This is an Open Access article, distributed under the terms of the Creative Commons Attribution 4.0 International License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution and reproduction in any medium or format, provided the original work is properly cited.
Copyright	Copyright © The Author(s), 2026. Published by Science Publishing Group

Keywords

Côte d’Ivoire, Mealybugs, Fertilizer, Physiological Parameters, Biochemical Parameters

References

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APA Style

N’Guessan, P. W., Koffi, S. K., Aboudou, D. K., Kotaix, A. A. J., Rusinamhodzi, L., et al. (2026). Effect of Fertilizer Application on Mealybug Infestation and Physiological Responses of Cocoa at the CNRA Station, Divo, Côte d'Ivoire. American Journal of Bioscience and Bioengineering, 14(5), 101-109. https://doi.org/10.11648/j.bio.20261405.12

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ACS Style

N’Guessan, P. W.; Koffi, S. K.; Aboudou, D. K.; Kotaix, A. A. J.; Rusinamhodzi, L., et al. Effect of Fertilizer Application on Mealybug Infestation and Physiological Responses of Cocoa at the CNRA Station, Divo, Côte d'Ivoire. Am. J. BioSci. Bioeng. 2026, 14(5), 101-109. doi: 10.11648/j.bio.20261405.12

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AMA Style

N’Guessan PW, Koffi SK, Aboudou DK, Kotaix AAJ, Rusinamhodzi L, et al. Effect of Fertilizer Application on Mealybug Infestation and Physiological Responses of Cocoa at the CNRA Station, Divo, Côte d'Ivoire. Am J BioSci Bioeng. 2026;14(5):101-109. doi: 10.11648/j.bio.20261405.12

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@article{10.11648/j.bio.20261405.12,
  author = {Pierre Walet N’Guessan and Stanislas Kouakou Koffi and Diallo Karim Aboudou and Alain Acka Jacques Kotaix and Leonard Rusinamhodzi and Richard Asare and Kouassi Allou},
  title = {Effect of Fertilizer Application on Mealybug Infestation and Physiological Responses of Cocoa at the CNRA Station, Divo, Côte d'Ivoire},
  journal = {American Journal of Bioscience and Bioengineering},
  volume = {14},
  number = {5},
  pages = {101-109},
  doi = {10.11648/j.bio.20261405.12},
  url = {https://doi.org/10.11648/j.bio.20261405.12},
  eprint = {https://article.sciencepublishinggroup.com/pdf/10.11648.j.bio.20261405.12},
  abstract = {Applying fertilizer is one solution for improving cocoa production. However, while it improves cocoa productivity, it also promotes the development of pests and disease vectors. This study aimed to understand the effects of fertilizer on the proliferation of mealybugs known as vectors of cocoa swollen shoot virus. The experimental design was a Fisher block with four fertilizer formulations (T1 to T4) and an unfertilized control (T0), each replicated three times. Each elementary plot contained 45 cocoa trees from CNRA research station in Divo, Côte d’Ivoire. Mealybug infestation levels were evaluated every 15 days for one year, and three cocoa leaves were collected per treatment and replication in order to determine physiological and biochemical parameters. The data were analyzed using SAS 9.4 and XLSTAT 2025. The results revealed seven species of mealybugs in the treatments: Formicococcus njalensis, Planococcus citri, Ferrisia virgata, Pseudococcus longispinus, Phenacoccus hargreavesi, Dysmicoccus brevipes, and Planococcus kenyae. Furthermore, analysis of variance revealed significant differences among the treatments regarding the content of chlorophyll A and B, total chlorophyll, carotenoids, protein, phenolic compounds, and proline. However, among the seven mealybug species identified, principal component analysis revealed a link between Formicococcus njalensis, Ferrisia virgata, and Dysmicoccus brevipes, as well as chlorophyll A and B, total chlorophyll, carotenoids, protein, phenolic compounds, and total sugars, in T0, T3, and T4. Meanwhile, the mealybug species Pseudococcus longispinus and Phenacoccus hargreavesi were linked to proline in treatment T2. Overall, the study showed that fertilizer has a small impact on mealybug and more on the physiological and biochemical parameters.},
 year = {2026}
}

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TY  - JOUR
T1  - Effect of Fertilizer Application on Mealybug Infestation and Physiological Responses of Cocoa at the CNRA Station, Divo, Côte d'Ivoire
AU  - Pierre Walet N’Guessan
AU  - Stanislas Kouakou Koffi
AU  - Diallo Karim Aboudou
AU  - Alain Acka Jacques Kotaix
AU  - Leonard Rusinamhodzi
AU  - Richard Asare
AU  - Kouassi Allou
Y1  - 2026/10/29
PY  - 2026
N1  - https://doi.org/10.11648/j.bio.20261405.12
DO  - 10.11648/j.bio.20261405.12
T2  - American Journal of Bioscience and Bioengineering
JF  - American Journal of Bioscience and Bioengineering
JO  - American Journal of Bioscience and Bioengineering
SP  - 101
EP  - 109
PB  - Science Publishing Group
SN  - 2328-5893
UR  - https://doi.org/10.11648/j.bio.20261405.12
AB  - Applying fertilizer is one solution for improving cocoa production. However, while it improves cocoa productivity, it also promotes the development of pests and disease vectors. This study aimed to understand the effects of fertilizer on the proliferation of mealybugs known as vectors of cocoa swollen shoot virus. The experimental design was a Fisher block with four fertilizer formulations (T1 to T4) and an unfertilized control (T0), each replicated three times. Each elementary plot contained 45 cocoa trees from CNRA research station in Divo, Côte d’Ivoire. Mealybug infestation levels were evaluated every 15 days for one year, and three cocoa leaves were collected per treatment and replication in order to determine physiological and biochemical parameters. The data were analyzed using SAS 9.4 and XLSTAT 2025. The results revealed seven species of mealybugs in the treatments: Formicococcus njalensis, Planococcus citri, Ferrisia virgata, Pseudococcus longispinus, Phenacoccus hargreavesi, Dysmicoccus brevipes, and Planococcus kenyae. Furthermore, analysis of variance revealed significant differences among the treatments regarding the content of chlorophyll A and B, total chlorophyll, carotenoids, protein, phenolic compounds, and proline. However, among the seven mealybug species identified, principal component analysis revealed a link between Formicococcus njalensis, Ferrisia virgata, and Dysmicoccus brevipes, as well as chlorophyll A and B, total chlorophyll, carotenoids, protein, phenolic compounds, and total sugars, in T0, T3, and T4. Meanwhile, the mealybug species Pseudococcus longispinus and Phenacoccus hargreavesi were linked to proline in treatment T2. Overall, the study showed that fertilizer has a small impact on mealybug and more on the physiological and biochemical parameters.
VL  - 14
IS  - 5
ER  -

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Author Information

Pierre Walet N’Guessan

Cocoa Program, National Agricultural Research Center, Divo, Côte d'Ivoire

Contact Email

http://orcid.org/0000-0002-4850-2275
Stanislas Kouakou Koffi

Cocoa Program, National Agricultural Research Center, Divo, Côte d'Ivoire;Agroforestry UFR, Jean Lorougnon Guede University, Daloa, Côte d'Ivoire
Diallo Karim Aboudou

Cocoa Program, National Agricultural Research Center, Divo, Côte d'Ivoire;Natural sciences UFR, Nangui Abrogoua University, Abidjan, Côte d'Ivoire
Alain Acka Jacques Kotaix

Cocoa Program, National Agricultural Research Center, Divo, Côte d'Ivoire
Leonard Rusinamhodzi

International Institute of Tropical Agriculture (IITA), Accra, Ghana
Richard Asare

International Institute of Tropical Agriculture (IITA), Accra, Ghana
Kouassi Allou

Department of Research and Innovation, National Agricultural Research Center, Abidjan, Côte d'Ivoire

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APA Style

N’Guessan, P. W., Koffi, S. K., Aboudou, D. K., Kotaix, A. A. J., Rusinamhodzi, L., et al. (2026). Effect of Fertilizer Application on Mealybug Infestation and Physiological Responses of Cocoa at the CNRA Station, Divo, Côte d'Ivoire. American Journal of Bioscience and Bioengineering, 14(5), 101-109. https://doi.org/10.11648/j.bio.20261405.12

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ACS Style

N’Guessan, P. W.; Koffi, S. K.; Aboudou, D. K.; Kotaix, A. A. J.; Rusinamhodzi, L., et al. Effect of Fertilizer Application on Mealybug Infestation and Physiological Responses of Cocoa at the CNRA Station, Divo, Côte d'Ivoire. Am. J. BioSci. Bioeng. 2026, 14(5), 101-109. doi: 10.11648/j.bio.20261405.12

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AMA Style

N’Guessan PW, Koffi SK, Aboudou DK, Kotaix AAJ, Rusinamhodzi L, et al. Effect of Fertilizer Application on Mealybug Infestation and Physiological Responses of Cocoa at the CNRA Station, Divo, Côte d'Ivoire. Am J BioSci Bioeng. 2026;14(5):101-109. doi: 10.11648/j.bio.20261405.12

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@article{10.11648/j.bio.20261405.12,
  author = {Pierre Walet N’Guessan and Stanislas Kouakou Koffi and Diallo Karim Aboudou and Alain Acka Jacques Kotaix and Leonard Rusinamhodzi and Richard Asare and Kouassi Allou},
  title = {Effect of Fertilizer Application on Mealybug Infestation and Physiological Responses of Cocoa at the CNRA Station, Divo, Côte d'Ivoire},
  journal = {American Journal of Bioscience and Bioengineering},
  volume = {14},
  number = {5},
  pages = {101-109},
  doi = {10.11648/j.bio.20261405.12},
  url = {https://doi.org/10.11648/j.bio.20261405.12},
  eprint = {https://article.sciencepublishinggroup.com/pdf/10.11648.j.bio.20261405.12},
  abstract = {Applying fertilizer is one solution for improving cocoa production. However, while it improves cocoa productivity, it also promotes the development of pests and disease vectors. This study aimed to understand the effects of fertilizer on the proliferation of mealybugs known as vectors of cocoa swollen shoot virus. The experimental design was a Fisher block with four fertilizer formulations (T1 to T4) and an unfertilized control (T0), each replicated three times. Each elementary plot contained 45 cocoa trees from CNRA research station in Divo, Côte d’Ivoire. Mealybug infestation levels were evaluated every 15 days for one year, and three cocoa leaves were collected per treatment and replication in order to determine physiological and biochemical parameters. The data were analyzed using SAS 9.4 and XLSTAT 2025. The results revealed seven species of mealybugs in the treatments: Formicococcus njalensis, Planococcus citri, Ferrisia virgata, Pseudococcus longispinus, Phenacoccus hargreavesi, Dysmicoccus brevipes, and Planococcus kenyae. Furthermore, analysis of variance revealed significant differences among the treatments regarding the content of chlorophyll A and B, total chlorophyll, carotenoids, protein, phenolic compounds, and proline. However, among the seven mealybug species identified, principal component analysis revealed a link between Formicococcus njalensis, Ferrisia virgata, and Dysmicoccus brevipes, as well as chlorophyll A and B, total chlorophyll, carotenoids, protein, phenolic compounds, and total sugars, in T0, T3, and T4. Meanwhile, the mealybug species Pseudococcus longispinus and Phenacoccus hargreavesi were linked to proline in treatment T2. Overall, the study showed that fertilizer has a small impact on mealybug and more on the physiological and biochemical parameters.},
 year = {2026}
}

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TY  - JOUR
T1  - Effect of Fertilizer Application on Mealybug Infestation and Physiological Responses of Cocoa at the CNRA Station, Divo, Côte d'Ivoire
AU  - Pierre Walet N’Guessan
AU  - Stanislas Kouakou Koffi
AU  - Diallo Karim Aboudou
AU  - Alain Acka Jacques Kotaix
AU  - Leonard Rusinamhodzi
AU  - Richard Asare
AU  - Kouassi Allou
Y1  - 2026/10/29
PY  - 2026
N1  - https://doi.org/10.11648/j.bio.20261405.12
DO  - 10.11648/j.bio.20261405.12
T2  - American Journal of Bioscience and Bioengineering
JF  - American Journal of Bioscience and Bioengineering
JO  - American Journal of Bioscience and Bioengineering
SP  - 101
EP  - 109
PB  - Science Publishing Group
SN  - 2328-5893
UR  - https://doi.org/10.11648/j.bio.20261405.12
AB  - Applying fertilizer is one solution for improving cocoa production. However, while it improves cocoa productivity, it also promotes the development of pests and disease vectors. This study aimed to understand the effects of fertilizer on the proliferation of mealybugs known as vectors of cocoa swollen shoot virus. The experimental design was a Fisher block with four fertilizer formulations (T1 to T4) and an unfertilized control (T0), each replicated three times. Each elementary plot contained 45 cocoa trees from CNRA research station in Divo, Côte d’Ivoire. Mealybug infestation levels were evaluated every 15 days for one year, and three cocoa leaves were collected per treatment and replication in order to determine physiological and biochemical parameters. The data were analyzed using SAS 9.4 and XLSTAT 2025. The results revealed seven species of mealybugs in the treatments: Formicococcus njalensis, Planococcus citri, Ferrisia virgata, Pseudococcus longispinus, Phenacoccus hargreavesi, Dysmicoccus brevipes, and Planococcus kenyae. Furthermore, analysis of variance revealed significant differences among the treatments regarding the content of chlorophyll A and B, total chlorophyll, carotenoids, protein, phenolic compounds, and proline. However, among the seven mealybug species identified, principal component analysis revealed a link between Formicococcus njalensis, Ferrisia virgata, and Dysmicoccus brevipes, as well as chlorophyll A and B, total chlorophyll, carotenoids, protein, phenolic compounds, and total sugars, in T0, T3, and T4. Meanwhile, the mealybug species Pseudococcus longispinus and Phenacoccus hargreavesi were linked to proline in treatment T2. Overall, the study showed that fertilizer has a small impact on mealybug and more on the physiological and biochemical parameters.
VL  - 14
IS  - 5
ER  -

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