단옥수수와 초당옥수수 종자의 활력을 높일 수 있는 저장 방법을 알기 위하여 단옥수수(Early Sunglow × Golden Cross Bantam 70)와 초당옥수수(Xtrasweet 82 × Fortune) 종자를 온도(5 및 15℃ )와 상대습도(70 및 85%)가 다른 조건에서 10개월간 저장한 후 종자 특성의 변화를 보면 다음과 같다. 1. 종자활력은 초당옥수수가 단옥수수보다 더 빨리 저하되었으며, 초당옥수수가 단옥수수보다 더 낮은 저장온도와 상대습도가 요구되었다. 2. 단옥수수는 저장조건과 저장기간에 따른 cold test에서 출아율이 25℃ 에서 발아율보다 약간 낮았으나 경향은 같았고, 초당옥수수는 cold test에서 출아율이 25℃ 에서 발아율보다 현저히 낮았다. 3. 단옥수수와 초당옥수수 모두 발아율과 저온처리 후 출아율과는 정의 상관이 있었으나 초당옥수수는 관계가 적었다. 그래서 초당옥수수의 포장 출아율을 추정하기 위하여 반드시 저온처리 후 출아율 검정이 필요하였다. 4. 단옥수수는 모든 저장조건에서 5개월간은 종자활력이 저하되지 않았으나, 초당옥수수는 5℃ , RH 70%에서 활력이 유지되었다. 5. 단옥수수에서는 종자활력과 침종시 종자의 당 누출, 전해질 누출 및 α-amylase 활성과는 상관이 없었다. 반면 초당옥수수에서는 종자활력과 α-amylase 활성과는 정의 상관이, 침종 시 종자의 전해질 누출과는 부의 상관이 있었으나 당 누출과는 상관이 없었다

In Korea, production of super sweet corn has been economically feasible and is substituting for traditional sweet corn due to better flavor in recent years. Major limiting factors for super sweet corn production are low field emergence and low seedling vigor. The optimum water potential (WP) for the priming of normal and aged seeds of dent, sweet (su) and super sweet (sh2) corns was studied to improve low seed quality. Seeds were primed at 0, -0.3, -0.6, -0.9, and -1.2 MPa of polyethylene glycol (PEG) 8000 solution at 15~circC for 2 days. Priming effects differed depending on the type of corn, seed quality, and WP of PEG solution. Although WP of priming solution did not influence the emergence rate of extremely high quality normal dent corn seeds, it reduced time to 50~% emergence (T50) and increased plumule weight. In contrast, the emergence rate of aged field corn was improved by seed priming at 0 MPa and plumule weight and α-amylase activity was enhanced. The optimum WP for both normal and aged sweet and super sweet corn seeds was between -0.3 and -0.6 Mpa. At the optimum WP emergence rate, α-amylase activity, and content of DNA and soluble protein increased, while T50 and leakage of total sugars and electrolytes reduced.

The production of sweet (su) and super sweet corns (sh2) has been economically feasible in Korea in recent years. Major factors limiting super sweet corn production are low germination and low seedling vigor. Since seed quality is closely related to seed maturity, the optimum harvest time for the seed production of sweet and super sweet corns was studied and the quality of seeds with varying maturities was investigated in 2001 and 2002 cropping seasons. The parents of the sweet corn seeds were Hybrid Early Sunglow and 'Golden Cross Bantam 70' and those of super sweet corn were Xtrasweet 82 and 'For­tune'. Seeds were harvested at 21, 28, 35, 42, 49, and 56 days after silking (DAS). As the seeds developed, seed weight of sweet corn increased and the seed moisture content decreased faster than that of super sweet corn. Germination rates of sweet corn seeds harvested 21 and 28 DAS at 25~circC and emergence rates in the cold soil test were significantly lower than those of seeds harvested after 42 DAS in both years. Although the germination rates of super sweet corn seeds with varying maturities showed similar patterns as sweet corn seeds at 25~circC , the emergence rate of super sweet corn seeds in cold soil test continuously increased with seed maturity. This suggests that seed quality of super sweet corn should be tested in a cold soil test to estimate field emergence. As the seeds developed, leakage of total sugars and electrolytes from the both sweet and super sweet corn seeds decreased up to 42 or 49 DAS. The α-amylase activities of both sweet and super sweet corn seeds increased with seed maturity from 21 to 35 or 49 DAS depending on genotype and year. The optimum harvest time for the seed production of sweet corn was 42 DAS and 49 DAS for super sweet corn considering emergence rate and plumule dry weight in the cold soil test, leakage of sugars and electrolytes from the seeds, and α-amylase activity.

비파괴적으로 활력이 낮은 종자를 선별해내는 방법의 기초를 확립하고자 유채, 배추, 무 종자를 상대습도 90%, 온도 45℃ 에서 인위적으로 퇴화시켜 종자활력과 종자를 물에 침지 할 때 분비되는 당의 종류, 분비량, 분비시간과의 관계를 구명한 결과를 요약하면 다음과 같다. 1. 모든 작물의 건전종자는 전당을 분비하지 않았지만 죽은 종자는 침지 후 4~8시간부터 전당을 많이 분비하였다. 2. 유채, 배추, 무의 건전종자는 sucrose와 g1ucose를 가장 많이 함유하였고, stachyose, fructose, raffinose도 함유하였다. 인공퇴화과정에서 stachyose, raffinose, sucrose는 줄고, glucose와 fructose는 증가하였다.