Incidence of seed-borne fungi in winter wheat and spring barley seeds

Abstract

Seed-borne fungi are important for quality of Poaceae grain crops. Fungi may reduce seed germination capacity, viability, weight, weaken the root system, to decrease on green mass and yield of plants. The aim of the research was ascertain the abundance of seed-borne fungi and estimate the influence of moisture content, weight, viability on the intensity of contamination by fungi. The grain of 3 winter wheat (Triticum aestivum L.) and 5 spring barley (Hordeum vulgare L.) varieties grown on Lithuanian seed production farms was used. In 2018 the total number of seed samples tested was 54 for winter wheat and 58 for spring barley, in 2019 – 48 and 44, respectively. The grains were analysed for moisture content, viability or germinating power, and 1000 grain weight. Fungal infection on seed was determined according to Satton et al. (2001) and Mathur, Kongsdal (2003) methods in a sterile environment in Petri dishes on Czapek–Dox agar medium (CDA). During the experimental period all the wheat seed samples were found to be dominated by the fungi of Alternaria, Fusarium, Penicillium and other fungi genera. The seed infection level was 52.9, 5.7, 5.9 and 35.5%, respectively. In all the barley seed samples were found to be dominated by the fungi of Alternaria, Penicillium, Fusarium, Drechslera and Cladosporium genera, the seed infection level was 40.3, 25.2, 16.3, 7.8 and 0.7 %, respectively. The highest Fusarium infection level was recorded when the moisture content of stored grain exceeded 14.1%. A higher correlation between grain moisture content and occurrence of Fusarium fungi (r=0.72, P=0.05) was identified for winter wheat. The occurrence of seed-borne fungi depended on the moisture content of stored grain. The differences in seed infection with pathogenic and saprophytic fungi in relation to grain weight were inappreciable. With increasing Fusarium infection level seed viability and germinating power declined.