Figure 1.

Aphid numbers, percentage (%) of trap sides with Turnip yellows virus (TuYV)-carrying aphids and canola (Brassica napus) crop virus incidence over the early period of the growing season at Coomalbidgup in 2017 (A) and 2018 (B), and at South Stirlings in 2018 (C). At each site, three double-sided yellow sticky traps were tied to the top of the fence and collected every two weeks. Aphids caught on each trap side were counted, pooled, homogenized, and the crude extract tested for TuYV by reverse transcription loop-mediated isothermal amplification. For canola crops, tip leaf samples of 100 to 200 plants tested for TuYV from ~GS12 (two-leaf stage; ‘BBCH’ decimal system, Lancashire et al 1991) by enzyme-linked immunosorbent assay.