Varietal Differences and Drying Storage Effects for Some Treatment Conditions of EMS and MMS on Rice Seeds

수도종자에 EMS와 MMS의 처리조건에 따른 건조저장효과와 품종간차이

In order to study the biolgiocal effects of dry back following EMS (Ethyl methane sulfonate) treatment on seeds of 'Dunghan Shali' that belongs to indica-type rice with various presoaking(24, 36, and 40 hrs respectivily) and treatment time(l, 2 and 3 hrs respectivily), this experiment was done. Seedling heights of wet seeds presoaked for 36 hrs was only greatly decreased with EMS treatment compared with other periods. In germination rate of wet seeds, all of these damage was not changed. For the drying back seeds, otherwise, seedling height and germination rate were greatly reduced depend upon the time of treatment and presoaking as well as storage effects after drying back. Reduction patterns, both seedling height and germination rate, between 1 week and 8 weeks after dry back were quite similar. The other experiment was carried out in order to study for the influences on the seedling growth as biological damage with EMS and MMS(Methyl methane sulfonate) treatments among different varieties. The indica-type rice varieties; Taichung Native No.1, Dunghan Shali and IR-8, were used as the experimental materials. From this trial some results were obtained as follows; 1. Both seedling growth and germination rate on all varieties, used, MMS, treatment showed more toxic effects than those of EMS treatment. 2. Seeding growth injury of rice seeds dried back was increased gradually, and then was approached the maximum at 6-8 days after storing. In IR-s variety, otherwise, growth damage was appeared a little. Germination rate of these were quite smilar, even though chemical used is different and storage period was prolonged. 3. It was showed clearly that varietal differences of chemical mutagene treatments were recognized.

인도형 수도종자(품종 : Dunghan Shali)에 전침지시간과 2% EMS 처리시간을 달리하여 습윤한 종자와 건조저장종자에서 생물학적 영향의 한 기준으로서 묘장과 발아율을 조사하였든바 습윤한 종자의 묘장에서 EMS 처리시간의 증가에 따라 그 감소는 특히 36시간 전침지하므로서 크게 나타났고 발아율에는 차이가 없었다. 건조저장한 종자에서는 묘장이나 발아율이 전침지와 처리시간의 증가에 따라 감소율이 크게 나타났다. 저장기간의 변동에 따른 발아율과 묘장에서는 건조 1주일부터 8주일 사이에는 차이가 없었다. 인도형 수도품종 : Taichung Native No.1, Dunghan Shali 및 IR-8의 건조종자를 2% EMS와 2.5% MMS로 처리하여 품종간에서 건조저장에 따른 생물학적 장해를 조사한 바 얻어진 결과는 다음과 같다. 1) Methyl group의 독성이 Ethuyl group의 화학약품처리에서 보다 묘생장이나 발아율에서 크게 나타났다. 2) 건조저장한 종자에서는 건조후 6-3일까지는 생육장해가 증대되어 최대에 달하였다. 그러나 IR-8에서만 미한 묘생장의 감소를 보였고 발아율에서는 차이가 없었다. 3) 품종간 차이로서는 화학약품별 건조저장일수에 따라 달리 나타나는 감수성에 대한 품종간 유전적 차이 정도로서 인정할 수 있었다.