ALFALFA SEED LOSSES AND QUALITY AS AFFECTED BY PRESENCE OF WEED SPECIES DURING PROCESSING

U radu su prikazani rezultati gubitaka sjemena lucerne tijekom dorade i kvaliteta sjemena nakon dorade. U ispitivanju je bilo sedam partija sjemena grupiranih po proizvođačima sa ukupno 58.683 kg sjemena. Udio sjemena korova u sjemenu prije čišćenja kretao se od 0,15 - 6,04%. Ovisno o proizvođaču broj vrsta korova bio je od pet do 17. Od sjemena korova koje se teško izdvajaju iz sjemena lucerne utvrđeno je prisustvo: Cuscuta spp., Rumex spp., Plantago lanceolata, Amaranthus retroflexus, Myosotis arvensis, Polygonum lapathifolium, Setaria spp. i Sorghum spp. Dorada sjemena obavljena je na selektoru i magnetskom odjeljivaču. Tijekom dorade izgubljeno je u prosjeku 20,4% sjemena lucerne (selektor 14,69%, magnetski odjeljivač 5,71%), odnosno 10.021 kg sjemena što odgovara tržnoj vrijednosti od oko 40.000 DEM. Na gubitke u doradi najveći utjecaj je imalo prisustvo sjemena korova koje se teško izdvaja iz sjemena lucerne (r = 0,735) i postotni udio korova u naturalnom sjemenu (r = 0,723) i ukupni udio korova u naturalnom sjemenu (r = 0,476).This paper presents the data on alfalfa seed losses during processing, as well as on the seed quality after processing. The investigation included seven seed lots classified according to the area of its origin, the overall quantity amounting to 58.683 kg. The portion of weed seed before processing ranged from 0,15 to 6,04%. Depending on the origin, the number of weed species ranged from 5 to 17. Among the weed seed that hardly separates from alfalfa seed we have found: Cuscuta spp., Rumex spp., Plantago lanceolata, Amaranthus retroflexus, Myosotis arvensis, Polygonum lapathifoIium, Setaria spp. and Sorghum spp. The machines for the processing were: air-screen cleaner and magnetic separator. During processing, 20,4% of alfalfa seed in mean was separated as useless (air-screen cleaner - 14,69%; magnetic separator - 5,71% ) and 10.211kg, respectively, corresponding to the market value of approximately 40.000 DEM. The quantity of useless alfalfa seed was most affected by the presence of weed seed that hardly separates from alfalfa (r = 0,735), as well as by percentage share of weed in the seed before processing (r = 0,683). The portion of ueseless alfalfa seed on the grading machine was affected by the seed quantity (r = 0,704) and the number of weed species the hardly separate from alfalfa seed (r = 0,523), whereas for the magnetic separator, it was affected by the presence of weed seed that hardly separates from the seed of alfalfa (r = 0,723) and by the overall potion of weeds in the natural seed (r = 0,476)