Effect of Fusarium seed infection and fungicide seed treatment on wheat and barley establishment and yield

The effects of three fungicide seed treatments (triazole plus imidazole (tri+im), fuberidazole (fub) and carboxin plus thiram (car+thi)) on establishment and yield of a number of paired seed lines of wheat cultivars with different levels of Fusarium infection were examined. Without seed treatment, lines of four cultivars with an average of 48% of seeds infected with Fusarium had between 9% and 23% lower establishment than lines with 7% of seeds infected. This reduction in establishment was not always directly related to laboratory germination. Tri+im slowed or reduced establishment of some seed lines. Seed lines infected with Penicillium spp. or bacteria had greatly reduced emergence and hence yield, and only car+thi improved emergence and yield of infected lines. A second trial examined the effects of tri+im and car+thi seed treatment on establishment and yield of a number of lines of barley cv. Valetta differing in Fusarium seed infection. In this trial, treatment with tri+im reduced field establishment in some seed lines, but did not affect yield, although treatment with car+thi produced a greater yield than tri+im. Additional key words: germination, Penicillium, bacteria