Genetics, Plant Breeding and Seed Production 254 48 th Croatian & 8 th International Symposium on Agriculture | Dubrovnik | Croatia ORIGINAL SCIENTIFIC PAPER The effect of microwave irradiation on the germination of barley seeds ( Hordeum vulgare L.) Crețescu Iuliana 1 , Velicevici Giancarla 2 , Ropciuc Sorina 3 1 Faculty of Animal Science and Biotechnologies, Banat’s University of Agricultural Sciences and Veterinary Medicine, Calea Aradului street 119, Timişoara, Romania (icretescu@animalsci-tm.ro) 2 Faculty of Horticulture and Forestry, Banat’s University of Agricultural Sciences and Veterinary Medicine, Calea Aradului street 119, Timişoara, Romania 3 Faculty of Forestry, University of Stefan cel Mare, Universitatii Street 13, Suceava, Romania Abstract This paper presents the research of the influence of microwave irradiation treatment on the development of barley seeds. A magnetron MWG20H emitting radiation with a frequency of 2.45 GHz has been used as a source of microwaves for the experiment. The exposure time varied from 0s, 30s, 60s, and 90s. The germination energy (GE) and germination (G) of seeds in %, on the 3 rd , 7 th and 10 th day was measured, aiming to estimate the influence of the microwave treatment. The best results have been obtained for variants with an exposure time of 30s and output power of 400W. Longer exposure times have an inhibition effect on plant development as well as higher output power of microwave irradiation. Key words: microwave irradiation, barley, germination. Introduction Microwaves are high frequency electromagnetic radiation, ranging from 300MHz to 300GHz, wavelengths between l m and l mm. The existence of microwave was first suspected mathematically by Maxwell, and then verified experimentally by Hertz in 1885. In agriculture, the energy of microwaves has been used to dry freshly harvested grains, to control the growth of fungi and insects and also for conditioning kernels before processing. The microwave irradiation can be used for short periods of time for obtaining significant changes on quality, and some properties of cereals, as would be distribution of triglycerides, catalase and peroxidase activities (Yoshida et al., 2000; Oprica, 2008), germination of cereals and other plants (Ponomarev et al., 1996; Aladjadjiyan and Svetleva, 1997; Aladjadjiyan, 2002; 2003; 2007; 2010). Microwave radiation treatment as a stimulating agent in agriculture has not been sufficiently investigated yet. The aim of this work is to determine the effect of microwave irradiation on different exposure times (0s-control, 30s, 60s and 90s) and on two irradiation power (720W and 400W) by investigating its influence on the early development stage of seeds from three genotypes of barley. Materials and methods The influence of microwave irradiation on barley seeds has been investigated before. A magnetron MWG20H with a frequency of radiation of 2.45GHz and maximum output power of 800W, according to supplier’s data, has been used as microwave source. The maximum density of irradiation has been estimated at 40kW/m 3 . The experiment was conducted in the laboratories of the Faculty of Horticulture and Forestry, Timisoara. The biological material used in this study was a collection of 3 genotypes of Romanian winter barley. The seeds were obtained from the Fundulea Agriculture Research Station.