Evaluation of onion (Allium cepa) germplasm entries for resistance to onion thrips, Thrips tabaci (Lindeman) in Tanzania
The article reports on efforts to identify the most resistant onion entries against Thrips tabaci
Abstract
Onion is one of the key horticultural crops in urban areas and a cash crop for rural families in Tanzania. Onion thrips, Thrips tabaci, is an important species infesting onion in the northern highlands of Tanzania. It not only causes considerable leaf damage by direct feeding, but also causes indirect damage through spreading the Iris yellow spot virus (IYSV) in onion. Onion growers predominantly rely on use of synthetic insecticides to control thrips, but most insecticides are ineffective. This is because thrips remain concealed in the plant while feeding, have overlapping generations, and have developed resistance to insecticides. Growing onion varieties that are resistant to onion thrips is an integrated approach that can manage the pest and IYSV.
The article reports on efforts to identify the most resistant onion entries against Thrips tabaci. After screening, several entries showed promise for use in breeding programmes aimed at developing varieties that are resistant to thrips, and which can be introduced for cultivation in Tanzania.
This is an output of the ‘Implementation of Integrated Thrips and Tospovirus Management Strategies in Small-holder Vegetable Cropping Systems of Eastern Africa’ project. It is partly funded by the UK Department for International Development, a core donor of the International Centre of Insect Physiology and Ecology.
Citation
Njau G.M., Nyomora A.M.S., Dinssa F.F., Chang J.-C., Malini P., Subramanian S. and Srinivasan R. (2017) Evaluation of onion (Allium cepa) germplasm entries for resistant to onion thrips, Thrips tabaci (Lindeman) in Tanzania. International Journal of Tropical Insect Science 37, 98–113. https://doi.org/10.1017/S1742758417000078