DIAGNOSTIC PROTOCOL TO IDENTIFY WILD OATS AVENA FATUA AND LUDOVICIANA BASED ON WIR HERBARIUM COLLECTION

The objective of the study is to develop a diagnostic protocol for the species identification of the fruits of common oats and Lyudovik oats, applicable to herbological research without the use of specialized, complex equipment. To achieve this goal, the following tasks were completed: to compile an up-to-date list of countries in which Avena L. species are included in phytosanitary lists as quarantine or harmful organisms; to identify conserved morphological traits of common oat and Lyudovik oat spikelets based on an analysis of scientific literature and the study of herbarium specimens; and to develop and illustrate a glossary of morphological traits of oat spikelets, incorporating terminology accepted in botany and agricultural practice, adapted for use by specialists without specialized botanical education. A comprehensive analysis of specialized sources was conducted, including scientific monographs, reference publications, and authoritative online resources on botany and plant taxonomy. In 2025, a morphological and diagnostic revision of the oat specimen collection from Weed Fund of the Herbarium of Cultivated Plants of the World, Their Wild Relatives and Weeds (WIR, St. Petersburg) was conducted. The collection was examined using a binocular microscope (magnification up to 40×). The selection of herbarium specimens was based on the completeness of their morphological structures. The identified herbarium specimens were used to photographically record morphological characteristics. A protocol for identifying oats by spikelets was developed, based on the following traits: the nature of the spikelet articulation with the inflorescence axis, the structure of the lemma apex, their pubescence, the presence of spines, and the color and structure of the caryopsis. The protocol was supplemented with a glossary and photo illustrations of key taxonomic traits of oats based on herbarium specimens stored in the Weed Fund of the WIR Herbarium (St. Petersburg). The developed protocol can be used by specialists in the fields of phytosanitary control, agronomy, and seed production when preparing products for international trade, including in 18 countries where field oats are put on the lists of quarantine and invasive plants.