K.V. McCully1, J.A. Ivany2, M. Melanson1, M. Price3 and A. Smith3
(Partner: New Brunswick Soil and Crop Improvement Association)
Abstract: A trial to evaluate various herbicide treatments on crop tolerance and weed control was conducted on both Aubade and Barspectra ryegrass varieties in Hartland, New Brunswick. Visual evaluations on crop tolerance and weed control were collected throughout the season. In addition, yields, thousand kernel weights, and percent germination data were also collected. Results indicated that the only treatments to cause crop injury levels greater than 10% anytime throughout the season, on both Barspectra and Aubade varieties, were Refine Extra + Agral 90 applied at 20 g/ha + 0.2% v/v, and 40 g/ha + 0.2% v/v. Injury levels were as high as 21% and 25% from Refine Extra + Agral 90 (20 g/ha + 0.2% v/v) on Barspectra and Aubade varieties respectively (10 days after treatment), and 34% to 36% from Refine Extra + Agral 90 (40 g/ha + 0.2% v/v) on Barspectra and Aubade varieties respectively (10 days after treatment) . Injury was in the form of crop stunting with a slight off colour. Injury lasted approximately 6 to 7 weeks. By the final rating, no significant crop injury was observed from any of the treatments.. Yield and percentage germination data also indicated that differences amongst treatments were not significant on either Aubade or Barspectra ryegrass varieties. Thousand kernel weights from treatments applied to Barspectra were not significantly different from each other, but were on Aubade. Only MCPA Na 300, Buctril M (2 L/ha), and Dyvel had thousand kernel weights not significantly lower than the untreated control on Aubade ryegrass. All treatments provided excellent lamb's quarters control (99-100%) by the final rating (July 22). Results from these trials indicated that any of the tested herbicides and rates could be used safely and effectively on both Barspectra and Aubade ryegrass varieties. Further testing with Refine Extra + Agral 90 may be warranted to verify tolerance however.
1Potato and Horticulture Branch, NBDARD, Fredericton, NB E3B 5H1
2Agriculture and Agri-Food Canada - Crops and Livestock Research Centre, Charlottetown, PEI C1A 7M8
3Livestock and Livestock Feed Branch, NBDARD, Fredericton, NB E3B 5H1