Influence of the air drying temperature on germination and dormancy of cocksfoot seeds (Dactylis glomerata L.)

Cocksfoot is one of the most important forage grasses, with specific reference to arid conditions. It is mainly used as a component for the preparation of grass-legume forage mixtures. One of the major problems in the production of grass seed is seed dispersal and loss of some yeld. However, harvesting can be done before the stage of technological maturity of seeds where the losses are reduced but, the quality of the seed may be a problem in this case. On the other hand immediately after harvesting, as well as a period of time after harvesting the seed, the grass is characterized by the presence of dormant seeds. Seed dormancy can be decreased with optimum temperature and moisture during the air seed drying. The harvested seed had the moisture content from 20% to 35%. Then the seeds are dried at temperatures of 90oC, 80oC, 70oC, 60oC, 50oC, 40oC, 30oC and at all temperatures the seeds exhibited 90, 60, 30 minutes. In laboratory conditions, seed germination (%), dormant seed are determined in six genotypes. Selection of the optimal temperature and drying time can significantly effect on the increase in seed germination of both seed moisture. Genotypes with high moisture according to the germination, showed low variability (moisture content was 20% and CV ranged from 2.0 to 4.1%; moisture content was 35% and CV ranged from 1.8 to 3.9%). Ježevica je jedna od najznačajnijih krmnih trava, sa posebnim značajem za aridne uslove. Uglavnom se koristi kao komponenta za sastavljanje travno-leguminoznih krmnih smeša. Jedan od većih problema u proizvodnji semena trava je osipanje semena i gubitak dela prinosa. Međutim žetvu je moguće obaviti i pre faze tehnološke zrelosti semena gde se gubici smanjuju ali može biti problem sa kvalitetom semena. Na drugoj strani odmah nakon ubiranja žetve kao i neki vremenski periodpo žetvi semena, trave se odlikuju prisutnošću dormantnog semena. Ućešće dormantnog semena se može smanjiti a povećati klijavost uticajem optimalne temperature vazduha prilikom sušenja gde i vlažnost semena ima uticaja. Ispitivano je seme sa sadržajem vlage: 20% i 35%. Zatim je seme sušeno na temperaturama vazduha: 90oC, 80oC, 70oC, 60oC, 50oC, 40oC, 30oC i klasično. Seme je vremenski izlagano na pomenutim temperaturama vazduha 90, 60 i 30 minuta. U laboratoriskim uslovima utvrđivana je klijavost ( % ) i dormantnost semena ( % ) šest genotipova ježevice. Izborom optimalne temperature vazduha i vremenom sušenja moguće je značajno uticati na povećanje klijavosti semena obe vlažnosti. Genotipovi sa visokom klijavošću su prema klijavosti ispoljili nisku varijabilnost (vlažnost 20% CV = 2,0-4,1%; vlažnost 35% CV = 1,8-3,9%).