Healthy seeds are essential for the optimal plant population and yield, but seed-borne pathogens, such as Fusarium spp., may reduce seed germination, quality and cause damping-off of the seedlings. Fusarium graminearum is a dominant pathogen of cereal crops and can cause significant losses of grain yield and quality. It is important to evaluate the role of alternative inoculum source in crop rotation. The aim of this study was to assess the impact of F. graminearum infection on different plant seed germination and seed infestation. The research was conducted at the Institute of Agriculture, Lithuanian Research Centre for Agriculture and Forestry, in 2017. Visually healthy seeds of bean (Vicia faba L.), pea (Pisum sativum L.), lupine (Lupinus angustifolius L.), soybean (Glycine max. (L.) Merr.), lucerne (Medicago sativa L.), white (Trifolium repens L.) and red (Trifolium pratense L.) clover were inoculated with 10 mL of F. graminearum suspension, adjusted to 1×106 conidia per mL. Seed infection was counted 2 and 6 days after inoculation (DAI), seed germination energy and reduction rate – after 3 DAI and germination index – 6 DAI. Results showed that all inoculated seeds were covered with typical to F. graminearum red-purple mycelium. The results of inoculated seeds with F. graminearum showed red-purple mycelium growth on the seeds (infection from 21.25 up to 100%). The results showed that germination energy decreased on pea (2.56%) and lupine (7.79%) seeds. Our results suggest that various plant seeds differently react to F. graminearum infection. The highest infection of F. graminearum was obtained on pea, lupine seeds and the least on red clover.

Evaluation of virulences of Blumeria graminis f.sp. hordei was started in Latvia in 1981, first in the Baltic States. Until 1994 the observations were carried out only in the central part of Latvia - Salaspils. As the climatic factors and the used barley varieties in various parts of Latvia are different, in 1995 we started regular observations of the particularities of the genetic structure of the pathogen population also in Daugavpils. The aim of this investigation was to detect particularities of the genetic structure of the pathogen population in different parts of Latvia in 1996-2000.