논문 상세보기
pp.22-26
본 연구는 벼의 출수 후 일수에 따라 수발아 양상을 조사하고 수발아 피해가 발생할 수 있는 시기를 예측하여 수발아 방제를 위한 기초자료를 얻고자 수행하였으며, 그 결과를 요약하면 다음과 같다.
1. 벼 등숙기간 중 호품벼는 출수 후 20일, 신동진벼는 출수 후 30일부터 수발아 조건이 충족되면 발아가 시작되었으며, 50% 이상의 종자가 발아력을 갖는 시기는 호품벼가 약 35일, 신동진벼가 약 45일이었고, 출수 후 50일에는 두 품종에서 모두 80% 이상의 종자가 발아하였다.
2. 한 이삭 내에서 종자의 위치에 따른 수발아의 순서는 상위부 > 중위부 > 하위부 순으로 나타났으며 지경별로는 2차 지경보다는 1차 지경의 것이 높게 나타났다.
3. 수발아 검정 시 미발아된 종자는 배의 미숙, 종자휴면, 종자의 등숙불량 (불완전립)이 원인인 것으로 판단되었다.
4. 출수 후 30~45일의 등숙중기에 신동진벼는 호품벼보다 종자 휴면성이 높았다.
This research was implemented to investigate pre-harvest sprouting characteristics in two Korean rice cultivars, Shindongjin (SDJ) and Hopum (HP). The panicles of both varieties were sampled after 15 days after heading (DAH) to 60 DAH at intervals of 5 days. As soon as sampled, the panicles were imbibed in water for 14 days at 25℃ to determine the vigor and germination ability of seeds according to location on panicle. To investigate the cause of non-germination of seeds in panicles, tetrazolium test and dormancy breaking were performed. The preharvest sprouting of HP started at 20 DAH while that of SDJ began at 30 DAH. The germination of seeds located in high rank branches within a panicle and the terminal seeds within a branch were earlier and faster and the germination patterns were same in both cultivars. The times at more than 50% of germination in a panicle were 35 DAH (57.0%) in HP and 45 DAH (56.8%) in SDJ. Preharvest sprouting was more than 80% at 50 DAH (82.6% of HP, 92.3% of SDJ) and more than 99% at 60 DAH (99.5%, 99.4%, HP and SDJ). These results indicated that the rate of PHS in a panicle increased with accumulation of the days after heading. The cause of non-germinated seeds at 15-25 DAH in panicle was immature embryo. After 30 DAH, however, when the non-germinated seeds were hulled, they started to germinate due to dormancy breaking, in which the germination percentage was higher in SDJ than HP. In conclusion, the pre-harvest sprouting varied according to days after heading, the seed position on panicle, and the dormancy intensity of varieties.
