벼의 Lipoxygenase-3 (LOX-3)는 벼의 저장 후 종자 수명과 고미취 발생에 관련이 있다. LOX-3 결핍은 저장 후 종자수명 향상과 고미취 발생 저감에 효과가 있는 것으로 알려져 있다. 본 연구는 국내 대면적 재배 품종인 새누리의 근동질계통으로 LOX-3가 결핍된 전주624호의 고온 저장 후 종자 수명과 고미취 관련 특성을 분석함으로써 LOX-3 결핍 대립유전자 도입에 따른 저장 후 효과를 구명하고자 수행되었다. 건열 처리 및 고온 저장 후 발아율 검정에서 LOX-3 결핍 자원인 다우담과 전주624호가 LOX-3 보유 품종인 남평과 새누리에 비해 발아율이 높았다. 고온 저장 후 지방산가 함량은 저장 전후 모두 전주624호가 가장 낮았고, 함량 차이는 다우담(2.0 KOH mg/100g), 전주624호(2.2), 남평(4.0), 새누리(4.2) 순으로 LOX-3 결핍 자원이 LOX-3 보유 품종에 비해 적었다. 고온 저장 후 LOX 효소 활성은 저장 전후 모두 다우담이 가장 낮았고, 활성 차이는 다우담(4.8 unit/mg protein), 전주 624호(8.9), 남평(20.30), 새누리(22.72) 순으로 LOX-3 결핍자원이 LOX-3 보유 품종에 비해 적었다. 고온 저장 후 hexanal 함량은 저장 전후 모두 전주624호가 가장 낮았고, 함량 차이는 전주624호(1,333 peak), 다우담(1,839), 새누리(5,238), 남평(36,427) 순으로 LOX-3 결핍 자 원이 LOX-3 보유 품종에 비해 적었다. 전주624호는 새누리 유전 배경에 LOX-3가 결핍된 근동질계통으로 저장 후 종자 수명 향상과 고미취 저감효과가 확인되었다. 이를 통해 LOX-3 결핍 대립유전자의 도입은 저장 후 종자 수명 향상과 고미취 저감에 효과가 있을 것으로 판단되었다.

There is little information about the seed longevity of wild plants, although seed bank storage is an important tool for biodiversity conservation. This study was conducted to predict the seed viability equation of Agastache rugosa. The A. rugosa seeds were stored at moisture contents ranging from 2.7 to 12.5%, and temperatures between 10 and 50℃. Viability data were fitted to the seed viability equation in a one step and two step approach. The A. rugosa seeds showed orthodox seed storage behaviour. The viability constants were KE=6.9297, CW=4.2551 CH=0.0329, and CQ=0.00048. The P85 of A. rugosa seeds was predicted to 152 years under standard seed bank conditions. The P85 predicted by seed viability equation can be used as basic information for optimization of seed storage processes.

벼의 형태적·생태적 특성을 나타내는 주두색, 망색, 영색,종피색, 입장 및 입폭과 생태적 특성을 나타내는 종실의 탈립성, 배유형, 원산지 및 종실 건조특성이 4oC 저장고에 보존된벼 3,066점의 종자수명에 미치는 영향을 알아보기 위하여 그들의 상관관계를 분석한 결과는 다음과 같다.1. 벼 종자의 탈립성과 저장력과의 관계는 고도로 유의한(p<0.0001)정의 상관관계를 보였다. 탈립성이 강한 벼 종자일수록 종자수명이 길게 나타났다.2. 벼 종자의 입장이 길고, 입폭이 좁은 것일수록 종자수명이 길었다. 입장이 길고 입폭인 좁은 종자의 건조 특성은 같은 상대습도 조건에서 건조될 때 종자의 평형수분함량이 낮게나타났다. 3. 망색과 종자 저장력의 관계에 있어서 자주색 망을 가진자원이 종자수명이 긴 것으로 조사되었다.4. 종자 저장력에 영향을 끼치는 벼의 형태적·생태적 특성의 상대적 중요도는 탈립성이 50.2로 가장 컸고, 이어서 입장과 망색이 각각 21.9와 7.7로 분석되었다.

밀양 23호/기호벼 유래 164 RILs(F17)을 이용하여, 종자의 휴면과 관련이 있는 수발아 저항성, 건열 저항성 및 종자수명을 검정하고, 이들 상호간 상관관계를 조사하였다. 출수 40일째에 밀양23호와 기호벼의 수발아율은 0%, 7%이었고, M/G RILs은 0~50.9%의 범위를 보였으며, 평균 3.2%였다. 90℃, 24시간 건열처리후 밀양23호와 기호벼는 99.2%, 37.6%의 발아율을 보였고, T50은 2.7일, 12.9일로 유의한 차이를 보였으며, M/G RILs의 평균 발아율은 72.4%였다. 상온저장 한 종자수명은 밀양23호는 수확후 3.5년까지도 80% 이상의 종자 발아율을 유지하였으나, 기호벼는 18개월 후부터 급격히 발아력이 감소하여(30%이하), 42개월 후 발아력을 완전히 상실하였다. M/G RILs의 종자활력은 수확후 42개월까지 71계통이 90%이상의 발아율을 보였다. 수발아 저항성, 건열 저항성 및 종자수명은 밀양 23호와 기호벼 간에 뚜렷한 품종간 차이를 보였으며, M/G RILs은 양친의 중간값에 가까운 평균값을 보였다. 건열저항성과 종자수명 간에는 고도로 유의한 정의 상관관계를 보였고, 수발아와 종자수명, 수발아와 건열저항성 간에는 부의 상관관계가 성립하였다.

The influence of rainfall during the ripening stage on pre-harvest sprouting, seed viability, and seed quality was investigated in two Korean rice cultivars, Shindongjin and Hopum. When the rainfall was artificially treated in a greenhouse, HP started to pre-harvest sprouting at three days of rainfall treatment (DRT), but Shindongjin did not show pre-harvest sprouting at 40 DAH treatment and just 0.3~0.8% at 50 DAH, which was much lower than 15.3~ 25.8% of Hopum in the same treatment. After harvest, the seed germination of Hopum decreased about 10~25% compared to non-treated seeds, but that of Shindongjin decreased much little rate than that of Hopum. The seed longevity tested by accelerated aging decreased with prolonged rainfall period in both cultivars, but the varietal difference was clear; Shindongjin could withstand longer accelerated aging than Hopum. Shindongjin maintained its germination (>50%) ability after 15 days of accelerated aging regardless of the rainfall treatment period and time, but Hopum dropped below 50% germination ability after only 5 days of accelerated aging. In conclusion, rainfall during the ripening stage induced not only pre-harvest sprouting, but also reduced seed quality and longevity during storage, which varied between two cultivars.

The purpose of this study was to develop the cost-effective and efficiency seed longevity prediction method of rice (Oryza sativa L.) germplasm for viability monitoring. To find an optimum predicting method for rice seed longevity at genebank, an accelerated ageing (AA) test, a controlled deterioration (CD) test and a dry-heat treatment (DHT) were conducted to the four groups of rice germplasm based on ecotype, such as Indica, Japonica, Javanica and Tongil type. Among the three artificial aging treatments, the dry-heat treatment of 36 hours at 90°C is suggested as a routine predictive test method of rice germplasm longevity at a genebank. The distribution of germination rate on 3,066 accessions which conserved 26.5 years at 4°C showed similar trend with the result of distribution by dry-heat treatment at 90°C on 36 hours using 106 accessions of rice selected samples which composed four ecotype groups. The results show that the dry-heat treatment affect not only predicting the rice seed longevity but also determining effective interval for monitoring germination of rice germplasm in genebanks.

The purpose of this study was to know the seed longevity of rice (Oryza sativa L.) germplasm for effective viability monitoring. The longevity was determined via germination tests of 3,066 accessions of rice germplasm from the National Agrobiodiversity Center, Rural Development Administration, Korea. The rice germplasm accessions have been conserved at a mid-term storage (4°Csealed metal can on either sides for 25~26.5 years. The final germination percentages of 3,066 rice germplasm accessions of 6.5±1.0% seed moisture content with 94% initial germination stored at 4°C for 26.5 years declined to 47% while at -18°C for 25 years maintained high germinability as 93%. Germination time courses, which represent the average performance of rice ecotypes stored at 4°C and 30% RH, were fitted regression equation, to calculate the time at which germination characteristically declined to 50% (P50). These P50 values of Indica, Japonica, Javanica and Tongil type in rice were 39.9, 22.9, 25.4 and 31.8 years, respectively. The rice germplasm stored at 4°C could be clustered in 4 groups using quartile of final germination after 26.5 years storage. The seed longevity (P50) of each group was estimated by regression equation of changed germination percentages according to storage periods. The P50 values of group Ⅰ, group Ⅱ, group Ⅲ and group Ⅳ were 21.1, 23.6, 30.0 and 75.7 years.

It is well known that Dharial (Bangladesh origin and weedy rice line) has longer seed longevity than indica and japonica rice varieties. To study the genetic basis of seed longevity of Dharial, we developed 240 BC3F7 backcross recombinant inbred lines derived from the crosses between Dharial (a donor parent) and two korea rice accessions (recurrent parents) including Ilmi and Gopum, respectively. Among these lines, we selected two introgression lines with longer seed longevity and named them Ilmi-NIL and Gopum-NIL. Also, we developed an EMS-induced mutant line from Dharial which has shortened seed longevity, and named it Dharial-EMS. We performed re-sequencing of four rice accessions that are Dharial, Dharial-EMS, Ilmi-NIL, and Gopum-NIL. A total of 706×106 raw reads were generated which provided sequence data over 46x rice genome coverage per each accession. We did genome-wide variation analysis comparing produced re-sequencing data and the re-sequencing data of Ilmi from NABIC database with the Nipponbare reference sequence. By graphical analysis of SNP distribution in rice genome of the five accessions, we could select candidate chromosomal segments introgressed from Dharial in Ilmi-NIL and Gopum-NIL. The introgressed chromosomal segments were in seven regions in Ilmi-NIL and eight regions in Gopum-NIL, and four common introgressed regions between Ilmi-NIL and Gopum-NIL were identified. 2,758 SNPs between Dharial and Dharial-EMS were found in the introgressed regions. Also, we detected 450 genes including at least one SNP among these SNPs. This result will facilitate identification of genes and development of molecular markers for improvement of seed longevity.