이탈리안 라이그라스의 염해반응에 대한 기초 자료를 얻고자 NaCl의 8개 농도에서 14개 품종(2배체:7 4배체:7)의 발아율과 유묘건물중, 엽록소 및 유리 proline함량을 조사하였다. 1. 발아율은 NaCl 300mM 이상에서 크게 감소하였으며 대조구에 대한 50%의 발아감소 NaCl농도는 344mM이었다. 2배체품종은 4배체품종보다 감소 정도가 컸으며 NaCl의 농도가 높을수록 발아율에 대한 품종들의 차이가 크게 나타났다. 2. 지상부 건물중은 NaCl 166mM에서 대조구에 대한 50%의 감소율을 보여 발아기보다 유묘기에 NaCl에 대한 영향이 더욱 컸는데, 품종들의 발아율과 지상부 건물중과는 상관관계가 없었다. 3. 지하부 건물중은 NaCl농도가 높아질수록 감소 정도가 커서 NaCl 148mM에서 50%의 감소가 나타났으며, 품종들의 지상부 건물중과 지하부 건물중은 유의적인 상관관계가 있었다. 4. 지상부 건물중과 지하부 건물중은 NaCl의 각 농도에서 2배체가 4배체보다 높았다. 5. Total 엽록소 함량은 NaCl농도가 높아질수록 증가하였는다 엽록소 a가 엽록소 b보다 함량이 더욱 증가하였으며, 엽록소 a는 4배체가 2배체보다 높았으나 엽록소 b는 2배체가 4배체보다 높았다. 품종들의 엽록소 a함량과 지상부 건물중과는 NaCl 150mM 이상에서 높은 상관관계가 인정되었다. 6. 유리 proline함량은 NaCl처리에 의하여 현저히 축적되었는데 2배체와 4배체 사이에는 별다른 차이가 없었으며, 품종들의 지상부 건물중과도 상관관계가 없었다.
This study was conducted to obtain the basic information for the salt stress of Italian Ryegrass. Fourteen cultivars including 7 diploid and 7 tetraploid were subjected to eight levels of NaCl treatments during germination and early seedling stages. Germination percentage decreased remarkably over 300mM of NaCl concentration. The NaCl concentration that inhibited germination of 50% of the viable seeds in the cultivars was 344mM. The decreasing degree of germination percentage was higher in tetraploid type than in diploid type. The varietal difference of germination percentage was shown to be very conspicuous as the NaCl concentration increased. Top dry weight in 166 mM NaCl was decreased by 50% compared with that of control. Inhibition of NaCl appeared to be more in early seedling stage than in germination stage. Top dry weight of cultivars in NaCl stress was not related with germination capacity. Root dry weight in 148mM NaCl decreased by 50% compared with that of control. Root dry weight of cultivars was significantly correlated with top dry weight in NaCl treatment. Top dry weight and root dry weight was higher in diploid type than in tetraploid type at each 8 levels of NaCl concentration. Total chlorophyll content increased with the increase of NaCl concentration and the degree of increase in chlorophyll a was higher than that in chlorophyll b. Chlorophyll a was higher in tetraploid type than in diploid type. But chlorophyll b was higher in diploid type than in tetraploid type. There were significant correlation between chlorophyll a and top dry weight of cultivars over 150mM of NaCl concentration. Free proline content accumulated remarkably in NaCl treatment compared with control and was not difference between diploid type and tetraploid type. Free proline content of cultivars was not related with top dry weight in NaCl treatment.