Effectiveness of priming treatments in breaking seed dormancy in Myrtle (Myrtus communis L.)

Mirta (Myrtus communis L.) je višegodišnja, zimzelena biljna vrsta. Svježi i osušeni plodovi koriste se u prehrambenoj industriji, a iz listova se izdvaja eterično ulje koje nalazi primjenu u farmaceutskoj industriji i aromaterapiji. Generativno razmnožavanje mirte je otežano zbog fizikalne i fiziološke dormantnosti sjemena, što predstavlja problem u poljoprivrednoj proizvodnji. S ciljem utvrđivanja učinkovitosti predsjetvenih tretmana u prekidanju dormantnosti sjemena mirte, postavljen je pokus na Agronomskom fakultetu Sveučilišta u Zagrebu. Ispitana je učinkovitost hladne stratifikacije, tretmana giberelinskom kiselinom (koncentracije 250 i 500 ppm) i kemijske skarifikacije sa sumpornom kiselinom na prekidanje dormantnosti sjemena mirte, kao i njihov utjecaj na parametre klijavosti (ukupna klijavost sjemena, prosječno vrijeme klijanja, prosječna stopu klijavosti, koeficijent varijabilnosti vremena klijanja, pouzdanost i ujednačenost procesa klijanja, indeks klijavosti). Najviši postotak klijavosti (90 %) utvrđen je kod tretmana s giberelinskom kiselinom koncentracije 250 ppm. Najduže prosječno vrijeme klijanja od 13,53 dana utvrđeno je kod hladne stratifikacije, a najkraće kod tretmana sumpornom kiselinom (8,44 dana). Najveća vrijednost indeksa klijavosti utvrđena je kod tretmana sumpornom kiselinom i giberelinskom kiselinom koncentracije 250 ppm (2,28), a najmanja kod hladne stratifikacije (1,48).Myrtle (Myrtis communis L.) is a perennial, evergreen plant species. Fresh and dried fruits are used in the food industry, and the essential oil extracted from the leaves is used in the pharmaceutical industry and aromatherapy. Generative propagation of myrtle is hampered by the physical and physiological dormancy of the seed, which represents a problem in agricultural production. To determine the effectiveness of priming treatments in breaking the dormancy of myrtle seeds, an experiment was set up at the University of Zagreb Faculty of Agriculture. The effectiveness of various pre-sowing treatments (cold stratification, soaking seeds in GA3 of 250 and 500 ppm for 24 h, and chemical scarification with H2SO4 for 2 minutes) has been determined to break dormancy and improve germination (germinability, mean germination time, mean germination rate, coefficient of variation of the germination time, uncertainty of the germination process and synchrony of the germination process). The study resulted in high percentage of germination in the treatments, and the highest percentage of germination (90%) was found in the treatment with 250 ppm of gibberellic acid. The cold stratification treatment had the longest mean germination time of 13.53 days, while the shortest was observed in the sulfuric acid treatment (8.44 days). The highest value of the germination index had the treatment with 250 ppm of gibberellic acid and sulfuric acid (2.28), and the lowest value was observed in the control stratification treatment (1.48)