The seed moisture content (MC) is one of the key factors affecting the seed longevity. It was generally recognized that a further reduction in seed MC below the empirical critical MC (5%) could induce harmful effect o...The seed moisture content (MC) is one of the key factors affecting the seed longevity. It was generally recognized that a further reduction in seed MC below the empirical critical MC (5%) could induce harmful effect on seed viability. However, some studies have showed that there is no harmful effect induced by ultradrying in some seeds, and that the storability of ultradried seed is improved during past ten years. It was recently demonstrated that drying seed beyond the optimum MC provided no additional benefit to longevity and may even accelerate the rate of aging. Further researches on the determining of the optimum seed MC might lead to a debate regarding the various parameters involved. Because of the differences in chemical composition of seeds, seed MC can not reflect the actual state of water in seed. Studies on physical state as well as thermodynamic analysis of water in seed would provide theoretical bases for ultradry seed storage.展开更多
: The effects of ultradry storage on the starch mobilization in maize (Zea mays L.) seed after aging were investigated. The results indicated that there were no significant differences in the content of ATP, starch, a...: The effects of ultradry storage on the starch mobilization in maize (Zea mays L.) seed after aging were investigated. The results indicated that there were no significant differences in the content of ATP, starch, and soluble sugar, as well as the activity of amylase, between ultradried seeds and seeds stored at ?20 °C during germination. These results were consistent with the higher level of vigor of the ultradried seed. Sieve tube introduction of a fluorescence dye (carboxyl fluoresceindiacetate) and laser confocal microscopy were used to study the development of plasmodesmata in the ultradried seeds. The results indicated that plasmodesmata developed well in ultradried seeds. Fluorescence analysis also showed that the fluorescence intensity in the radicle of ultradried seeds was stronger than that in seeds with a higher moisture content. This suggests that ultradry treatment has no adverse effects on the seeds. After seed imbibition, cell orgaelles could be resumed. It is concluded that ultradry seed storage is beneficial for maintaining seed vigor and that starchy mobilization proceeds regularly during germination.展开更多
文摘The seed moisture content (MC) is one of the key factors affecting the seed longevity. It was generally recognized that a further reduction in seed MC below the empirical critical MC (5%) could induce harmful effect on seed viability. However, some studies have showed that there is no harmful effect induced by ultradrying in some seeds, and that the storability of ultradried seed is improved during past ten years. It was recently demonstrated that drying seed beyond the optimum MC provided no additional benefit to longevity and may even accelerate the rate of aging. Further researches on the determining of the optimum seed MC might lead to a debate regarding the various parameters involved. Because of the differences in chemical composition of seeds, seed MC can not reflect the actual state of water in seed. Studies on physical state as well as thermodynamic analysis of water in seed would provide theoretical bases for ultradry seed storage.
基金Basic Research and Development Plan of China，中国科学院资助项目，Life Science Special Fund of the Chinese Academy of Sciences by the Ministry of Finance
文摘: The effects of ultradry storage on the starch mobilization in maize (Zea mays L.) seed after aging were investigated. The results indicated that there were no significant differences in the content of ATP, starch, and soluble sugar, as well as the activity of amylase, between ultradried seeds and seeds stored at ?20 °C during germination. These results were consistent with the higher level of vigor of the ultradried seed. Sieve tube introduction of a fluorescence dye (carboxyl fluoresceindiacetate) and laser confocal microscopy were used to study the development of plasmodesmata in the ultradried seeds. The results indicated that plasmodesmata developed well in ultradried seeds. Fluorescence analysis also showed that the fluorescence intensity in the radicle of ultradried seeds was stronger than that in seeds with a higher moisture content. This suggests that ultradry treatment has no adverse effects on the seeds. After seed imbibition, cell orgaelles could be resumed. It is concluded that ultradry seed storage is beneficial for maintaining seed vigor and that starchy mobilization proceeds regularly during germination.
