Diversity and abundance of aphids [Homoptera: Aphididae] and their impact on the spread of viruses infecting potato in Mali
Studies on the abundance and diversity of aphids were conducted during three crop seasons in Mali. Based on the survey of yellow traps set in potato crops in Kati and Sikasso, 2,525 winged aphids were collected and identified. Nineteen species of aphids were identified, two of which were also observed in situ on potato plants: Aphis gossypii (Glover) and Myzus persicae (Sulzer). Most of these species are crop pests and they also contribute to viral transmission. Leaf samples taken in potato plots in both regions were tested by ELISA for the detection of two major viruses: Potato Virus Y (PVY) and Potato Leaf Roll Virus (PLRV). The rate of virus-infected plants at both locations during the three years ranged from 19.3% to 21.8% for PVY, and from 8.5% to 9.3% for PLRV. The occurrence of these viral diseases was very consistent from one year to the next, with relatively high levels. This study is the first survey conducted in this region of Mali on the importance of aphids and associated viruses in potato fields.