Studies on the environmental control for the mass propagation of the tissue cultured plantlets by direct ex-vitro rooting method

本研究探讨了用离体直接生根法进行组培苗的快速繁殖。在该方法中，将从试管中的小植株切下的外植体（每个都具有叶子的单节插条）插入塞盘中的岩棉塞中，并直接转移到环境控制单元中，并在培养皿中培养。（无糖）稀释营养液用于水培。第一年，研究了太阳辐射和CO_2浓度对马铃薯试管苗直接生根的影响。将外植体置于环境控制单元中，在不同的太阳辐射强度和CO_2浓度下培养。所有的外植体在每个处理中都能生长成小植株并存活。并将该方法与常规方法的试管苗生长情况进行比较。在高光照和CO_2浓度条件下，直接离体生根法比常规生根法生长更快、更健壮。结果表明，试管苗具有光合作用能力，在无糖培养基上，只要控制好光合作用的物理环境，试管苗就能进行自养生长，第二年，还研究了人工基质的体积和表面积对试管苗生长的影响，即基质中养分和溶解氧的含量。结果表明，基质的体积和表面积影响试管苗的生长。因此，进一步研究根区环境对试管苗生长的影响是十分必要的。看来，以木本植物为外植体的研究是很有必要的。

In this study, the mass propagation of the tissue cultured plantlets by direct ex-vitro rooting method were discussed. In this method, the explants, single node cuttings each with leaves, excised from the plantlets in vitro were inserted in rockwool plugs in the plug tray and were transferred directly to the environmental control unit and were cultured with a (sugar free) diluted nutrient solution for hydroponics.On the first year, the effects of solar radiation and CO_2 concentration on the growth of potato plantlets with the ex-vitro direct rooting method was examined. Explants were cultured inside the environmental control unit at different intensities of solar radiation and CO_2 concentrations. All the explants grew to the plantlets and survived in each treatment. The growth of the plantlets with this method were compared with the growth of the plantlets with the conventional method. The plantlets grew faster and were more vigorous under high solar radiation and CO_2 enriched conditions in direct exvitro rooting method than that under general conditions in conventional method. It was shown that the plantlets have a photosynthetic ability and they can grow autotrophically on the sugarfree medium if the physical environment is properly controlled for the autotrophic growth by photosynthesis.On the second year, the effects of the volume and surface area of the artificial substrate, which affects the content of nutrient and dissolved oxygen in the substrate, on the growth of plantlets was also examined. It was shown that the volume and surface area of the substrate affected the growth of the plantlets. It seems that the further investigation about the effects of the root zone environment on the growth of the plantlets. It seems that the investigation about woody plants as explants will be needed.