A Dissertation Submitted in Partial Fulfillment of the Requirement for the Degree of
Masters in Life Sciences of the Nelson Mandela African Institution of Science and
Technology
This study was conducted from February to March and July to August 2019 in twenty-four
(24) cashew fields located in the southern and central zones of Tanzania. In each zone, three
districts were selected based on cashew production reports, and in each district, four farms
were selected. In each farm, ten fully-grown cashew nut trees were randomly selected and
assessed for infestation by sucking insect pests. The insect pests were assessed within
quadrants of one-meter length placed at the north and south of the canopy of the cashew tree.
The total number of insect pests, susceptible shoots and nuts, both clean and damaged were
recorded. Insect samples were collected and identified at the Tropical Pesticides Research
Institute, Arusha Tanzania. Twenty-seven (27) key informant farmers were interviewed using
questionnaires and farmers group discussions in both zones. The study revealed a number of
both known and first recorded insect pest’s attacks that cashew nut. The commonly known
insect pests identified include Helopeltis sp, Pseudotheraptus wayi, Selenothrips rubrocinctus
and Mecocorynus loripes, and newly recorded were Miphetophora sp., Plaesiorrhira sp.,
Diplognatha gagates, Systates sp, and Aphis sp. The incidence and diversity of these cashew
sucking insect pests differed in terms of abundance and distribution within cashew fields.
Most abundant insect pests were Helopeltis sp. with incidences of 46.7%. Further research is
required in studying biology, ecology population dynamics and abundance of first reported
and identified insect pests to determine specific periods for intervention and develop methods
(species-specific) for effective pest management in Tanzania.