Occurrence and distribution of Papaya Mealybug (Paracoccus marginatus Williams and Granara de Willink) (Hemiptera: Pseudococcidae) in the coastal area of Kenya

Abstract

Papaya mealybug, Paracoccus marginatus Williams and Granara de Willink (Hemiptera: Pseudococcidae) was first reported in Kenya in 2016. Kenya Plant Health Inspectorate Service (KEPHIS) together with other collaborators has since continuously carried out surveillance and management initiatives to contain the pest. In November and December 2020, a delimiting survey of the papaya mealybug (PMB) was conducted in six coastal counties. The survey was aimed at determining the incidence and intensity of infestations in the farms, host range in the region and to assess the farmers’ awareness on management options. Sixty-seven (67) farms were randomly sampled across the six counties. An open data kit (ODK) mobile tool generated questionnaires were administered to collect data on PMB incidence, infestation intensity and management practices applied and their effectiveness based on responses from farmers. Papaya mealybug was confirmed to occur in the six counties surveyed with incidences which ranged from 10- 100%. The intensity of infestation in the counties varied from very low to medium based on the applied scale and was higher on fruits compared to the leaves, stems and flowers. The survey further revealed that PMB infested citrus, sugarcane, okra and custard apple that were initially not reported as hosts. Majority (65%) of the farmers interviewed were aware about the occurrence of PMB on their crops and could positively identify and describe it. Some farmers had tried to manage the pest and the lowest incidence (3%) was recorded from fields where farmers combined chemical and cultural practices for management. In order to contain the impact and spread PMB, authorities and research institutions in Kenya may need to consider deploying classical biological control management which has successfully been deployed in other countries.

Key words: Delimiting survey, incidence, infestation intensity, Kenya, papaya mealybug.