A Short Growing Season Negatively Affects Progeny Vigor in Jointed Goatgrass (<i>Aegilops cylindrica</i>)

Abstract

Seed production and percent germination in jointed goatgrass were negatively affected by a shorter vernalization period in field studies conducted at Oregon State University. Our objective was to determine if a shorter growing season experienced by a maternal jointed goatgrass plant similarly affected seedling vigor in the progeny. Seed mass, percent germination, emergence, seedling height and biomass, including roots, were recorded or evaluated on progeny that were produced from three jointed goatgrass populations grown under a long or short growing season in a common garden experiment in eastern Oregon, an area where jointed goatgrass is known to commonly infest natural resources, including winter wheat. Seeds produced under a shorter growing season weighed less, were slower to germinate, and displayed lower percent germination compared with seeds produced under a long growing season. Seedlings from a short growing season were slower to emerge, and produced less shoot biomass compared to seedlings produced under a long growing season. Seedling roots and shoots were shorter when seeds were produced under a short growing season. A shorter growing season negatively affected jointed goatgrass seedling vigor. If resources for jointed goatgrass management are limited, strategies should focus on controlling plants that emerge in the fall, because they have the potential to produce more vigorous seedlings compared to plants that emerge in late winter or early spring.