초록
이탈리안라이그래스의 발아기 내염성에 대한 기초자료를 얻고자 온도가 $25^{\circ}C$, 2$0^{\circ}C$ 및 15$^{\circ}C$인 조건에서 NaCl의 농도를 350mM까지 8개의 수준으로 조절하여 2배체형의 9품종과 4배체형의 11품종을 치상하여 발아상태를 조사하였다. 1. 발아율은 온도, NaCl의 농도 그리고 품종들에 따라 각각 유의적인 차이가 인정되었다. 2. NaCl의 무처리에서 품종들의 발아율은 2$0^{\circ}C$에서 90.1%로 $25^{\circ}C$에서의 87.8%나 15$^{\circ}C$에서의 87.5%보다 높았다. 3. 품종들의 평균발아율은 NaCl의 농도가 200mM에서 감소하기 시작하였으며 감소농도는 2$0^{\circ}C$에서 15$^{\circ}C$나 $25^{\circ}C$보다 높았다. 4. 2$0^{\circ}C$에서 품종들의 발아속도는 NaCl의 농도가 높아질수록 늦어졌고 발아율도 낮았다. 5. 평균발아일수는 온도가 낮고 NaCl의 농도가 높아질수록 점차 길어졌다. 6. 2배체형은 4배체형보다 온도와 NaCl의 농도에 관계없이 발아율이 높았으며 평균발아일수는 짧았다.
This study was conducted to obtain the basic information on salinity tolerance in Italian Ryegrass. Seeds of 20 cultivars that contained diploid(9 cultivars) and tetraploid(l1 cultivars) types were exposed to eight levels of NaCl concentration ranging from 0 to 350 mM under three levels (15$^{\circ}C$, 2$0^{\circ}C$ and $25^{\circ}C$) of temperature. There were highly significant differences in germination percentage among the levels of NaCl concentration, levels of temperature and cultivars, respectively. Average germination percentage of cultivars in control(no NaCl was higher at 2$0^{\circ}C$(90.1%) than that of $25^{\circ}C$(87.8%) or 15$^{\circ}C$(87.5%). Average germination percentage of cultivars began to decrease over 200mM of NaCl concentration. The degree of decrease in germination was higher at $25^{\circ}C$ than that of 15$^{\circ}C$ or 2$0^{\circ}C$. At 2$0^{\circ}C$, the germination percentage and gemination speed were gradually decreased as NaCl concentration increased. The average germination day was lengthened by the increase of NaCl concentration and temperature. The germination percentage in diploid types were higher than that of tetraploid types but the average germination day in diploid types was shortened more than that of tetraploid types, regardless of temperature and NaCl concentration.