The Relationship Between the Germination of Silky Bent Grass (Apera spica-venti (L.) Beauv.) Diaspores and Their Age, Place of Occurrence, and Action of Stimulating Substances

Apera spica-venti is a weed that is threatening agricultural crops worldwide. Current reports do not fully agree on the biology of the weed, regarding the viability of diaspores, nor is there sufficient information on how different factors affect the germination of its seeds, such as the abundance of soil where the mother plant (plants from which diaspores (caryopsis) were collected) has grown or the effect of biostimulants on their germination. Therefore, the main aim of this study was to compare the germination of newly harvested seeds of A. spica-venti (3 months after harvest) with seeds that had been stored for 1, 2, 3, 4, or 5 years. Furthermore, the influence of seed age, weed location, and biostimulants (silicon and algal liquids) on the germination of A. spica-venti diaspores was checked. Three-year-old seeds showed the highest percentage of germination, and their germination process was positively correlated with soil abundance (from sites of mother plant material collection) and macronutrients (N, P, K). The strongest correlations were recorded for 3- and 4-year-old seeds. A. spica-venti seeds treated with biostimulant preparations were characterized by varying percentages of germination. No clear trend was noted regarding the germination capacity of the harvested seeds as the diaspores aged, and it depended on the type of stimulant and the place of origin of the seed. Moreover, seeds from the harvest year treated with the stimulant were characterized by a higher germination percentage. A. spica-venti is a highly fecund weed, a trait that makes it very common in crops, appearing en masse and providing formidable competition to crops, thus causing significant yield losses. Awareness of the vitality of diaspores will allow for the possible regulation and control of this weed in order to prevent yield loss in crops. The theme of diaspore viability warrants further investigation. Further research should include observations of factors affecting germination, including new stimulants emerging on the agricultural market.