Faba beans are considered to be one of the most important leguminous crops. The species is characterized by high nutritional value, in terms of both energy and protein content, which makes it suitable for food and feed production. Fungal diseases are among the key biotic factors responsible for a decline in faba bean yields. In this study, the yield and health status of faba bean seeds from the region of Warmia and Mazury (WM) and the region of Lower Silesia (LS), in Poland, were determined. Correlations between weather conditions vs. the yield of faba bean seeds and the occurrence of saprophytic and pathogenic fungi were analyzed. The study revealed that temperature and precipitation influenced the development and yield of faba beans in successive growth stages. Temperature exerted the greatest effect on the yield of faba beans during inflorescence emergence (BBCH 55-Biologische Bundesanstalt, Bundessortenamt and CHemical Industry), whereas the effect of precipitation was the maximum at the 4-5 leaves unfolded stage and at the end of flowering (BBCH 69). The occurrence of saprophytic, pathogenic, and toxin-producing fungi was influenced by temperature and precipitation in the flowering stage (BBCH 61-64).Agronomy 2020, 10, 48 2 of 13 20 fungal species belonging to 13 genera, i.e., Aspergillus, Penicillium, Alternaria, Botrytis, Cephalosporium, Cladosporium, Epicoccum, Fusarium, Rhizoctonia, Rhizopus, Stemphylium, Trichothecium, and Verticillium, were isolated from faba bean seeds. Pathogenicity tests revealed that Cephalosporium sp., F. solani, F. oxysporum, F. verticilioides, R. solani, and V. dahliae were the most pathogenic fungi isolated from decaying faba beans seeds. The cited authors observed correlations between the incidence of diseases caused by the above fungi and the concentrations of total phenols, chlorophyll a, chlorophyll b, and carotenoids in plant tissues, and they concluded that pathogen-free seeds must be used to produce high-quality faba beans. Pathogenic fungi not only decrease crop yield and quality, but also produce mycotoxins-toxic secondary metabolites that contaminate foodstuffs and feedstuffs [14]. According to Gleń [15], the suitability of seeds for human consumption, as animal feed, and as planting material is determined by their microbiological purity. Adequate plant protection during the growing season can improve the health status of seeds, while synthetic fungicides that are highly effective can be used for controlling phytopathogens. Fungal colonization significantly decreases seed vigor and germination capacity and causes plant infections during the growing season [16]. Due to considerable varietal differences, faba bean cultivars are characterized by different susceptibility to fungal infections. In Poland, faba bean yields and disease resistance are significantly affected by variable weather and soil conditions [12]. Global climate change is also an important consideration in agricultural production [17]. According to Fahad et al. [18], suboptimal water supply and temperatu...