Abstract
The objective of this study was carried out to determine which method is effective for improving seed germination in carrot and onion among osmotic or solid matrix priming. Seeds were osmotic primed with -0.5 MPa polyethylene glycol 8000 (PEG) solution and solid matrix primed with Micro Cel E (seed, Micro Cel E, and water mixed with the ratio of 4.0：2.0：8.0 by weight for carrot, and the ratio of 4.0：1.2：5.0 for onion at $20^{\circ}C$ for 4 days). Seeds were rapidly absorbed water after osmotic priming and solid matrix priming treatment. The moisture content of solid matrix primed seeds was lower than that of osmotic primed seeds in carrot and onion. Osmotic priming and solid matrix priming did not influenced on increasing of percent germination, but $T_{50}$ of treated seeds was shorter than those of untreated seeds at four temperature regimes. The effects of osmotic or solid matrix priming in reducing the $T_{50}$ was greater when the seeds were germinated at $15^{\circ}C$ than at $25^{\circ}C$ and $30^{\circ}C$ temperature. Solid matrix primed seeds germinated faster than osmotic primed seeds at all temperature in both carrot and onion. After priming, surface-dried seeds germinated faster than dried-back seeds in carrot and onion. Emergence speed of carrot and onion seeds was faster than untreated seeds by osmotic priming or SMP treatment although the final emergence percentage was not significantly influenced. On the other hand, early growth was not significantly influenced by osmotic priming or SMP treatment of carrot and onion seeds.
본 연구는 당근과 양파에서 발아력 증진에 미치는 osmotic priming과 SMP효과를 비교하기 위해 수행되었다. Osmotic priming과 SMP 처리과정중 작물별 수분흡수율은 처리 1시간 후 급속한 수분흡수가 이루어졌고, 두 작물 모두 osmotic priming이 SMP보다 수분흡수 속도가 빨랐다. 이러한 경향은 처리 4시간까지 유지되었다. 처리최종일의 수분흡수율은 당근과 양파에서 osmotic priming이 SMP보다 2%높았다. Osmotic priming과 SMP 처리는 두 작물 모두 발아율을 향상시키지 못했지만 $T_{50}$ 및 MDG는 단축되어 조기발아 하였으며, 이러한 경향은 저온인 $15^{\circ}C$에서 더욱 현저하였다. Osmotic priming과 SMP 처리 후 초기함수율로 재건조하면 당근에서는 발아속도에 큰 차이가 없었으나, 양파에서는 표면건조에 비해 발아속도가 지연되었다. Osmotic priming과 SMP 상호처리간 발아력을 비교한 결과 두 작물 모두 SMP 처리가 osmotic priming보다 발아촉진에 효과적이었다. 당근과 양파종자를 osmotic priming과 SMP 처리하면 묘출현율도 향상되었고, 묘출현에 소요되는 일수를 단축시켜 신속한 묘출현을 유도하였다. 그러나 묘출현에 이은 유묘의 초기생육에는 통계적인 유의성은 인정되지는 않았으나 osmotic priming과 SMP 처리된 종자는 무처리에 비해 향상되었다.
