Management practices effect on seed features of Italian ryegrass following storage period

Abstract

Italian ryegrass seed crop was established in 2007 with two sowing densities (D1 = 60 cm row spacing and 5 kg ha-1 seeding rate; D2 = 20 cm row spacing and 20 kg ha-1 seeding rate) and using two spring nitrogen rates (0 and 150 kg N ha-1). Seed germination and thousand seed weight (TSW) of Italian ryegrass was observed in first production year. After harvest in June, seeds were stored under standard storage conditions and sampled 90 days after harvest (DAH), and then 2000 DAH. At 90 DAH, seeds were tested for TSW, as well as germination energy and total germination percentage at incubation temperatures of 10, 15, 20 and 25°C. Ryegrass seeds had the best germination energy 90 DAH at 20°C and maximum total germination at 15°C, which implies that early autumn (September-October) is proper sowing period for freshly harvested seeds of Italian ryegrass. Italian ryegrass seeds could maintain satisfactory germination energy (59.3%) and total germination (77.3%) up to 2000 DAH. High seed quality was obtained and applied treatments did not change seed quality significantly unlike storage period which had considerable influence on seed quality. The data can serve for the determination of a proper storage duration management between harvest and sowing of the tested species under ambient conditions of Serbia.

Setva semenskog useva italijanskog ljulja obavljena je u 2007 godini u dve gustine setve (D1=60 cm međuredno i 5 kg ha-1 setvena norma; D2=20 cm međuredno i 20 kg ha-1 setvena norma) i primenom dve količine azota u prihrani (0 and 150 kg ha-1). Posmatran je klijavost i masa 1000 semena italijanskog ljulja u prvoj proizvodnoj godini. Posle junske žetve, seme je skladišteno u standardnim skladišnim uslovima i uzorkovano 90 dana posle žetve (DPŽ), a potom 2000 DPŽ. Posle 90 DPŽ seme je ispitivano na masu 1000 semena, energiju klijanja i ukupnu klijavost na temperaturama klijanja od 10, 15, 20 i 25°C. Seme ljulja je imalo najbolju životnu sposobnost 90 DPŽ na 20°C i maksimalnu ukupnu klijavost na 15°C, što sugeriše da je rana jesen (septembar-oktobar) odgovarajući period za setvu sveže požnjevenog semena italijanskog ljulja. Seme italijanskog ljulja može zadržati zadovoljavajuću energiju klijanja (59,3%) i klijavost (77,3%) i 2000 DPŽ. Dobijeno je kvalitetno seme i primenjeni tretmani pri gajenju semenskog useva nisu menjali značajno kvalitet semena, za razliku od dužine perioda skladištenja, koje je imalo značajan uticaj na kvalitet semena. Podaci mogu poslužiti za određivanje dužine perioda skladištenja semena između žetve i setve italijanskog ljulja u uslovima Srbije.