Screening potato for resistance to potato tuberworm

From 3,747 accessions of primitive cultivars and 452 accessions of wild potato species screened for resistance to Phthorimaea operculella (Zeller), 22 primitive and 21 wild potato accessions were identified as highly resistant. These accessions were found resistant to both tuber damage and successful pupation and are now being used in breeding resistance into potentially high-yielding potato varieties adapted to lowland tropics. Resistance is attributed to antibiosis.