Thrips threshold validation – commercial-scale experiments

Abstract

Key findings »» Thrips pressure reached the positive control threshold of one thrips per plant in late October while plants were at the cotyledon to 1-leaf stage. »» Thrips pressure reached the industry threshold of 10 thrips per plant in mid-November when plants were at the 4–5-leaf stage. »» Onion thrips were the dominant thrips species observed during monitoring. »»Western flower thrips (WFT) constituted less than 5% of thrips monitored. »» There was no yield difference between sprayed and unsprayed plots.