Integrative Analysis of Morphological and Biochemical Markers of Seeds in Several Fagopyrum esculentum Varieties

An integrative analysis of morphological, structural, and biochemical characteristics was performed for the first time in buckwheat seeds of several varieties grown in contrast conditions, namely, a monsoon climate of Primorsky Krai and a temperate continental climate of Central Russia. The intention was to develop important practical recommendations on the use of the new seed assessment method. Minor differences were observed in the color and weight of seeds and the weight and structure of seed coats. The total protein content in seeds was almost the same in all varieties, and differences in only minor components were detected in the protein composition. Total phenolic compound (TPC), phenylpropanoid (PhP), flavan (FL), and proanthocyanidin (PA) contents in seeds were similar between the varieties and were lower than in seed coats in most cases, with the exception the new-generation variety Desire. A significant accumulation of PAs (polyphenol oligomers with high antioxidant activity) was observed in buckwheat seed coats, suggesting their potential application in various industries.