2019 Volume 64 Issue 4 Pages 244-253
Interest in breeding timothy with improved plant competition including allelopathy is growing because of the serious invasion of quackgrass (Agropyron repens (L.) Beauv.) and reed canarygrass (Phalaris arundinacea L.) to the timothy-based grasslands in Hokkaido, Japan. This study investigated the varietal differences on allelopathy between the weeds and twelve timothy varieties. The percentage against the control of timothy root or shoot length showed significant varietal differences on resistance in germination test with weed water extract, plant-box method and agar-based method with the weeds. The potential allelopathic activity against weed root length also showed significant varietal differences in agar-based method with reed canarygrass. Yet, most of correlations among the methods were weak or almost absent in them on resistance. This may be attributable to the difference of function effects of allelochemicals, and suggests that comprehensive evaluation based on some tests should be desirable for evaluating the resistance. The relative ranking of varieties based on the percentage against the control showed some accordance in the results of between plant-box method or agar-based method and the early growth in the field test. These results suggest that selection focused on allelopathy may provide useful breeding improvement of timothy competitive ability.
