水稻耐鹽性에 관한 硏究 : 鹽分濃度가 主要 水稻品種의 發芽 및 幼苗의 發根에 미치는 影響 Effects of Salt Concentration on Germination and Rooting Activity of Seedling of Some Varieties Rice = Study on the Salt Tolerance of Rice Plant

다국어 초록 (Multilingual Abstract)

The purpose of this study was to search the variability of salt tolerance among the major rice varieties in the germination period by the difference in the rooting activity of the seedlings grown for 15 days after transplanting of 30-day-old ones in different salt solutions. The germination ability was checked under the temperatures of 15, 25 and 35℃, and 7 levels of salt solutions. such as 0, 0.15, 0.30, 0.50, 0.75, 1.00 and 1.50%, respectively. The rooting activity of 33rice cultivars was checked with salt solutions of 0, 0.15, 0.30, 0.50, 0.75 and 1.00%.
The results obtained are summarized as follows:
1. The germination percentage and the hermination speed were significantly increased as the temperature rose up from 15℃ to 25℃ and 35℃.
2. At the same temperature, the germination percentage and the germination speed of decreased as the salt concentration increased. This was more apparent at the low temperature(15℃ plot) than at the high temperature such as 25℃ and 35℃ plot. The salt damage in germination showed even more at lower concentration at the 15℃, than that at the 25℃, or 35℃.
3. The decreasing ratio of the germination percentage and the germination speed of the early, medium and late maturing cultivars were not greatly influenced at the high temperature as the salt concentration increased, but those at the low temperature were outstandingly decreased. Particularly, the early and medium maturing varieties were severely damaged at low temperature han at high temperature.
4. The germination speed of the rice cultivars that originated from japonjca and indica-japonica hybrids (Tongil lines) were generally impeded by increasing the salt concentrations. The degree of salt damage in germination was higher in Tongil lines than that of japonica varieties.
5. Remarkably significant negative correlations were recognized between slat concentrations, germination percentage and germination speed regarless of the origin of cultivars and maturing season. The relationship of salt concentration and germination speed was more distinguished and that showed marked correlation coefficient at the low temperature (15℃) than at the high temperature (25℃ or 35℃).
6. It follows that it may be resonable evaluate the salt tolerance of rice seeds by comparison of germination speeds at low temperature.
The tested 33 major cultivars for salt tolerance could be classfied as follow:
High; Palkweng, Palkum, Mangyeong, Dongjinbyeo, Dongimbyeo, Chucheongbyeo.
Medium; Tongil, josaengtongil, Hwanggeumbyeo, Geumgangbyeo, Palgwangbyeo, Taebaegbyeo, Chupungbyeo, Nampungbyeo, Yushin, Saesbyeolbyeo, Iri-332, Sameseongbyeo, Seogwangbyeo, Baegunchalbyeo, Jinjubyeo,Pungsanbyeo, Baegyangbyeo, Milyang-21, Milyang-22, Milyang-30, Milyang-42, Cheongcheongbyeo.
Low; Manseogbyeo, Hangangchalbyeo, Pungsanbyeo, Raekyung, Milyang-23
7. Plant height, root length and fresh root weight of seedings grown 15 days after transplating in different salt solution were gradually reduced with salt concentrations, but the number of roots was less affected than others.
8. There existed remarkably signifficant negative correlation between salt concentration and pant height, root length, and fresh root weight, and that with root length showed apparantly with comparison of the others.
9. The rooting activity of the cultivars was estimated by measuring root length in different salt solutions.
The tested cultivars for rooting activity could be classified into three groups as follows;
High; Josaengtongil, Hwanggeumbyeo, Yushin, Saesbyeobyleo, Pungsanbyeo
Middle; Tongil, Geumbyeo, Manseogbyeo, Palgwangbyeo, Taebaegbyeo, Chupung byeo, Hangangchalbyeo, Nampungbyeo, Palkweng, Palkum, Iri-322, Samseongbyeo, Seowangbyeo, Bagunchalbyeo, Jinjubyeo, Baegyangbyeo, Nagdongbyeo, Milyang-21, Milyang-22, Milyang-23, Raekyung, Milyang-30, Milyang-42, Cheongcheongbyeo, Dongimbyeo, Chucheongbyeo
Low; Mangyeong, Dongjinbyeo.