Field evaluation of the impact of Sahlbergella singularis Haglund infestations on the productivity of different Theobroma cacao L. genotypes in the Southern Cameroon

Mahob Raymond Joseph, Feudjio Thiomela R., Dibog Luc, Babin Régis, Fotso Toguem Y.G., Mahot H., Baleba Laurent, Owona Dongo P. A., Bilong Bilong C. F.. 2019. Field evaluation of the impact of Sahlbergella singularis Haglund infestations on the productivity of different Theobroma cacao L. genotypes in the Southern Cameroon. Journal of Plant Diseases and Protection, 126 (3) : pp. 203-210.

Journal article ; Article de recherche ; Article de revue à facteur d'impact
Post-print version - Anglais
Use under authorization by the author or CIRAD.

Télécharger (3MB) | Preview
[img] Published version - Anglais
Access restricted to CIRAD agents
Use under authorization by the author or CIRAD.
R.Babin-Field evalutation of the impact.pdf

Télécharger (1MB) | Request a copy


Abstract : Mirids (Sahbergella singularis and/or Distantiella theobroma) are the major pests of cacao farms in Africa. Cocoa production losses due to these species have been widely documented in West Africa. However, their impact on cocoa production is unknown in Central Africa, especially in Cameroon. Moreover, no data are available on the threshold level of fruits tolerance to mirid attacks. For these reasons, we assessed the effect of S. singularis on the productivity of ten cacao genotypes as well as the threshold number of the lethal feeding punctures to fruits under a randomized experimental design. Observations were made on three categories of fruits (cherelle, immature and mature/ripe). A control trial was also set up per batch. The overall results showed that 68.0% and 0.4% of fruits aborted, respectively, in mirid and control trials. The percentages of aborted fruits were significantly (p < 5%) different between cacao genotypes and ranged from 20 to 100%. Bonferroni test revealed six homogenous groups for cacao genotypes susceptibility to mirid attacks; SNK52 proved to be most tolerant/resistant, whereas two genotypes (UPA138 and SNK67) revealed more sensitive. In contrast, six genotypes (SNK07, IMC60 × SNK417, T60/887 × PA7, T79/501 × SNK479, UPA143 × ICS84, UPA143 × NA33) displayed similar sensitivity to mirid attacks. ANOVA showed that the threshold tolerance of tested fruits, expressed by the mean numbers of lethal feeding punctures, to S. singularis attacks was comparable between cacao genotypes. This new quantitative database improves our knowledge on the (i) threshold tolerance of fruits to S. singularis attacks and (ii) economic impact of this pest on cocoa production in Cameroon.

Mots-clés Agrovoc : Theobroma cacao, Miridae, Résistance génétique, Génotype, Perte de récolte, Expérimentation au champ

Mots-clés géographiques Agrovoc : Cameroun

Mots-clés complémentaires : Sahbergella singularis

Classification Agris : H10 - Pests of plants
F30 - Plant genetics and breeding

Champ stratégique Cirad : CTS 4 (2019-) - Santé des plantes, des animaux et des écosystèmes

Auteurs et affiliations

  • Mahob Raymond Joseph, Université de Yaoundé (CMR) - auteur correspondant
  • Feudjio Thiomela R., Université de Yaoundé (CMR)
  • Dibog Luc, IRAD (CMR)
  • Babin Régis, CIRAD-BIOS-UPR Bioagresseurs (KEN) ORCID: 0000-0002-3753-1193
  • Fotso Toguem Y.G., Université de Yaoundé (CMR)
  • Mahot H., IRAD (CMR)
  • Baleba Laurent, IRAD (CMR)
  • Owona Dongo P. A., IRAD (CMR)
  • Bilong Bilong C. F., Université de Yaoundé (CMR)

Source : Cirad-Agritrop (

View Item (staff only) View Item (staff only)

[ Page générée et mise en cache le 2021-06-12 ]