| Studies on the preservation of plant germplasm resources has important significance in the protection of biologic diversity and the selective breeding of new varieties.The diversity of plant germplasm resources is also a basilic premise to keep ecological equilibrium, and it is related to the survival of human beings and the trend of agriculture development directly. Whereas, since twenty century, people have had an only view to step economy out, then the protection of entironment were neglected.The incorrect way has led the diversity of plant germplasm resources to be destroyed continually.Today, market economy is developing at very fast speed, and people's living requirement are changing normally.So they are not paying attention to the material life which almost like the past years only, but they are also in pursuit of the high quality of the intellectual life, such as a good living environment.And this pursuit is going up gradually. Consequently, protecting entironment, protecting animal and plant germplasm resources, constructing a sustainable development society with a thriving ecological awareness, that have been a question for discussion in the whole world.Algae can not only be a kind of food, but they are also used in various ways, such as baits for aquiculture, the plant food in agricultural production and the raw materials for industry and medication.As a result, algae content so important economic value in National production. Therefore, as one part of plant germplasm, studies on the conservation of algae germplasm content vital significance equally. In the first instance, the author has summarized the pace of progress, the primary technology and the prospect of application in the field of the research on the conservation of higher plant and algae.In this text, Isochrysis zhanjiangensis and Isochrysis galbana 3011 are used as the experimental materials, which are preserved by the method of encapsulation–dehydration at normal temperature and low temperature.The author has discussed various factors that affect the livability of this two kinds of algae, such as temperature, light (dark), the effect of antifreeze (glycerin), water content of beads, the density of algae cells in the beads, conservation space, different materials of the wrappage, the speed of dehydration and so on.The results are as follows:1. The effect of temperature and glycerin on cell viability.When the beads were conserved without antifreeze in dark condition, the viabilities of two kinds of algae were low taking one with another, under three ranks of temperature saving for six months. Nevertheless, in comparison, the viability in 4℃was higher than the viability in 20℃and -30℃obviously.When the beads were immerged glycerin, the viabilities of Isochrysis zhanjiangensis and Isochrysis galbana 3011 increased much more, reaching to 63.3% and 61.0% respectively.This results are owing to the function of glycerin that acting as preventing freezing harm effectively. Further more, the low temperature of -30℃could take the cells'breathing down consumedly, so the viabilities were remarkably improved.When we extended storage life to 18 months, the viabilities of two kinds of algae could reach to 36.1% and 32.4% all the same, which supplied credible laboratorial gist for mid-long storage of these two kinds of algae.2. The effect of illumination on cell viability.It was finded that low illumination was markedly good at the viabilities of two kinds of algae.At 20℃and after six months, the viability of Isochrysis zhanjiangensis was 26.6% saving in low illumination, but only 0.4% in dark; the viability of Isochrysis galbana 3011 was 14.2% preserved with a little light, however 0.7% in dark merely.At 4℃, the viabilities of Isochrysis zhanjiangensis were respectively 23.2% and 3.6% in low illumination and in dark; and those were 11.0% and 2.9% respectively for Isochrysis galbana 3011.It indicated that two algae could both keep some photosynthetic intensity in a little light.3. The effect of water content in beads on cell viability.The viabilities of two kinds of algae changed analogously on water content in beads. They reduced as the water content going down at 20℃; and went up firstly, then falled down as the water content descending at 4℃, when the water content reached to 90.9%, the viabilities were highest. In addition, they were similar as 4℃at -30℃, but the viabilities were highest when the water content was 81.1%.4. The effect of the density of algae cells in the beads on cell viability.The viabilities of two kinds of algae changed analogously on the density of algae cells in the beads.When the density was 0.5×107/cell, under each water content and temperature, we could get much higher viabilities entirely.However, the viabilities were universally low when the density was 2.0×107/cell.5. The effect of conservation space, different materials of the wrappage and the speed of dehydration on cell viability.It was found that we used much little space to save beads, which was advantaged to higher viabilities.What's more, when the materials of the wrappage was made up of aluminum in stead of plastic,and we used the speed of dehydration as -0.9%/h, there conditions were also good for the viabilities.6. The mensuration of the growth curve and growth rate.In this paper, the author repectively measured the growth curve and growth rate of two kinds of algae for 6 months and 12 months.The results showed that these two kinds of algae both could revive normally after convalescence for a period of time.We have conserved two species of isokont golden brown algae by the method of encapsulation–dehydration at normal temperature and low temperature for the first time.By discussing and comparing, we have found that two algae could be preserved for mid-long period at appropriate conditions.Further more, the manipulation and saving conditions of the method of encapsulation–dehydration are relative easy, and the method doesn't need costly instruments and equipments. Consequently, it can be used for the mid-long term storage of algae germplasm.
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