Shea fruit-infesting fruit flies (Diptera: Tephritidae) and evaluation of infestation level according to the ethno-varieties in Western Burkina Faso

Shea fruit (Vitellaria paradoxa C.F. Gaertn.) has a high potential for alleviation of hunger and poverty in Burkina Faso. The fruit pulp is an important source of food for rural communities, especially at times of food shortages. In addition, the commercial value of the shea tree enables local women to gather and sell the fruit to increase their incomes. However, stakeholders in the shea sector noted that pulp rot was a major constraint to their activity. Ripe fruit from six ethno-varieties were sampled every 2 weeks from trees in six agroforestry parks over two consecutive years (2017 and 2018). Shea fruits were then incubated in the laboratory until the emergence of adult fruit flies. Seven fruit fly species were identified, the most important of which was Ceratitis silvestrii Bezzi (54.75% of the individual fruit flies that emerged), followed by Bactrocera dorsalis Hendel (41.16%). The average rate of fruit damage differed significantly between ethno-varieties and collection dates, ranging from 2.08 to 16.23% in early shea fruits fruiting season and from 39 to 66.61% in the middle of the season, depending on the ethno-variety and the season. Ethno-varieties ripening in the mid shea fruits fruiting season suffered more fruit fly attacks than early and late ripening ethno-varieties. This study provided interesting information which will be used in the development of strategies for the control of these insect pests.