Effect of Environmental Factors on Sprout Germination, Growth, and Storage of Six Aster Species

Abstract

To increase the utility of seeds in plant resources, seeds of 6 Aster species(A. incisus, A. hayatae, A. koraiensis, A. scaber, A. spathulifolius, and A. yomena) were subjected to experiments to develop adequate methods for sprout production. To study optimum germination conditions, germination rates of the seeds were analyzed at different temperature (15, 20, 25, and 30°C) and light conditions. A longitudinal growth experiment was performed in dark conditions for 10 days. Seedlings, with optimum germination rate and longitudinal growth, were placed in the light for 0-3 days to seek the adequate greening periods. Sprouts grown under optimum environmental conditions were placed in vessels with or without ventilation, and stored under 4°C and 10°C to examine storage environment and period. As a result of this analysis, seeds were selected that germinated over 50% within 12 days. Longitudinal growth was promoted at 20-25°C, and optimum growth was obtained with 7-9 days. As greening days increased longitudinal growth was retarded, but orbital growth of radicles and cotyledons was promoted. Considering all these factors, greening treatment of 2 days showed the best results. In a storage ability experiment, the best result was achieved by storage in vessels without ventilation under 4°C. Ventilation prevented rotting of sprouts, but reduced moisture contents of sprouts. Most sprouts were fresh at 4°C for 3-6 days. In particular, sprouts of A. hayatae and A. yomena had high keeping quality, and remained fresh over 3 days even at 10°C.