包埋玻璃化法超低温保存植物种质的研究进展

包埋玻璃化法是在玻璃化法和包埋脱水法基础上发展起来的超低温保存植物种质的新技术。它具有能同时处理大量材料,处理后恢复生长快,对材料的毒害作用较小及成芽率高等优点,已成功地用于辣根、山嵛菜等20余种植物,在植物种质资源的保存上显示出了巨大的应用潜力。本文介绍了包埋玻璃化法产生的背景及其优点, 阐述了包埋玻璃化法的基本方法和预培养、包埋、脱水、化冻及恢复培养等过程,比较了该法冻存后的效果和冻存后所形成植株的遗传稳定性,同时指出了进一步研究的重点。     

藻类种质超低温保存研究概况

藻类种质的超低温保存技术已受到广泛的重视。目前已对数千种、株的淡水和海水藻类进行过超低温保存。其中,绝大多数藻类是采用两步冰冻法保存。影响藻类存活的主要因素是两步法冰冻保存程序和藻类自身的抗冻性。鉴定存活率是超低温保存技术中的重要环节。由于两步法保存技术的局限性,玻璃化和包埋脱水法等新技术在某些藻类的种质保存中可能有较大的应用潜力。     

藻类种质超低温保存研究概况

藻类种质的超低温保存技术已受到广泛的重视。目前已对数千种、株的淡水和海水藻类进行过超低温保存。其中 ,绝大多数藻类是采用两步冰冻法保存。影响藻类存活率的主要因素是两步法冰冻保存程序和藻类自身的抗冻性。鉴定存活率是超低温保存技术中的重要环节。由于两步法保存技术的局限性 ,玻璃化和包埋脱水法等新技术在某些藻类的种质保存中可能有较大的应用潜力。     

包埋玻璃化法超低温保存植物种质的研究进展

包埋玻璃化法是在玻璃化法和包埋脱水法基础上发展起来的超低温保存植物种质的新技术.它具有能同时处理大量材料,处理后恢复生长快,对材料的毒害作用较小及成芽率高等优点,已成功地用于辣根、山嵛菜等20余种植物,在植物种质资源的保存上显示出了巨大的应用潜力.本文介绍了包埋玻璃化法产生的背景及其优点,阐述了包埋玻璃化法的基本方法和预培养、包埋、脱水、化冻及恢复培养等过程,比较了该法冻存后的效果和冻存后所形成植株的遗传稳定性,同时指出了进一步研究的重点.     

冰冻保存小新月菱形藻的包埋-玻璃化法

采用包埋-玻璃化法对小新月菱形藻进行冰冻保存,探讨玻璃化溶液(PVS)配方、装载液浓度和装载时间、脱水时间以及洗涤方法对冰冻保存存活率的影响。结果表明:小新月菱形藻在0℃预冷后50%PVS2装载60min,100%PVS2脱水60min,1mol·L-1蔗糖梯度洗涤30min的条件下存活率最高,为74.1%。包埋-玻璃化法不需要特殊的冷冻设备,冰冻程序操作简单,在藻类种质的超低温保存中有较大的应用潜力。     

超低温保存植物种质资源的新途径——小滴玻璃化法

超低温保存是一种安全、有效的种质资源保存途径,可长期保存种质资源。小滴玻璃化法是在滴冻法和玻璃化法上基础上发展起来的用于植物种质资源保存的新技术。本文综述了该方法的技术概念、主要优点、基本程序、应用前景及国内外研究现状。     

香蕉茎尖超低温保存过程中的细胞超微结构观察(简报)

超低温保存(Cryopreservation)通常称为液氮保存或LN(-196℃)保存,是目前植物种质资源长期稳定保存的理想方法,已经成功应用于多种植物种质资源保存。玻璃化法(Vitrification)超低温保存植物种质资源始于20世纪80年代末,Uagami等首次     

枇杷茎尖二步玻璃化法超低温保存的研究

超低温保存是目前植物种质资源长期稳定保存最理想的方法,而近几年发展的玻璃化超低温保存法具有设备要求简单、材料处理步骤简便及效果和重演性好等特点,倍受人们的青睐。国内外用玻璃化法成功地保存许多果树的种质资源。在对枇杷（Eriobotrya japonica Lindl．）花粉超低温保存取得成功的基础上,作者进行了枇杷茎尖玻璃化超低温保存的研究,以期建立枇杷茎尖超低温保存体系,为长期稳定保存枇杷种质资源提供技术支持。     

包埋-玻璃化法冷冻保存湛江等鞭金藻的研究

采用包埋-玻璃化法冷冻保存湛江等鞭金藻(Isochrysis zhanjiangensis),探讨了装载液成分和浓度、装载时间、脱水时间、洗涤液浓度及洗涤时间对超低温保存后存活率的影响。结果表明在20℃50%PVS(PVS:30%甘油(GLY) 20%乙二醇(EG) 10%二甲基亚砜(DMSO),用f/2培养基定容)装载4.5h,0℃100%PVS脱水50min,冻存24h后取出冻存管并迅速投入40℃恒温水浴中快速化冻约3min,1.0mol/L山梨醇洗涤40min条件下,湛江等鞭金藻的存活率最高,为54%。与常规的两步法和包埋脱水法相比,包埋-玻璃化法简单、快速且存活率高,在藻类种质保存中有广阔的应用前景。     

切花百合离体茎尖玻璃化法超低温保存研究

以切花百合西伯利亚试管苗离体茎尖为试材,通过正交设计试验对预培养培养基中蔗糖浓度、预培养时间和PVS2处理时间等影响超低温保存存活率的主要因素进行了分析,初步建立了切花百合种质玻璃化法超低温保存的技术方案。通过形态观察、可溶性蛋白和同工酶检测,冻存前后材料的遗传稳定性没有发生改变,表明该方法对切花百合的种质保存具有较强的实用意义。     

In vitro conservation of Dendrobium germplasm

Dendrobium is a large genus in the family Orchidaceae that exhibits vast diversity in floral characteristics, which is of considerable importance to orchid breeders, biotechnologists and collectors. Native species have high value as a result of their medicinal properties, while their hybrids are important as ornamental commodities, either as cut flowers or potted plants and are thus veritable industrial crops. Thus, preservation of Dendrobium germplasm is valuable for species conservation, breeding programs and the floriculture industry. Cryopreservation represents the only safe, efficient and cost-effective long-term storage option to facilitate the conservation of genetic resources of plant species. This review highlights 16 years of literature related to the preservation of Dendrobium germplasm and comprises the most comprehensive assessment of thorough studies performed to date, which shows reliable and reproducible results. Air-drying, encapsulation–dehydration, encapsulation–vitrification, vitrification and droplet-vitrification are the current cryopreservation methodologies that have been used to cryopreserve Dendrobium germplasm. Mature seeds, pollen, protoplasts, shoot primordia, protocorms and somatic embryos or protocorm-like bodies (PLBs) have been cryopreserved with different levels of success. Encapsulation–vitrification and encapsulation–dehydration are the most used protocol, while PLBs represent the main explant explored.     

Phenotypic and molecular studies for genetic stability assessment of cryopreserved banana meristems derived from field and in vitro explant sources

Explants used for cryopreservation of banana (Musa L. spp.) are mainly sourced from tissue culture. Here, we demonstrate the successful use of sucker meristems (SM) obtained from field-raised plants for cryopreservation of Indian Musa ABB cv. ‘Karpura Chakkarakeli’. In addition, the genetic stability of plants recovered from cryopreserved and regenerated meristems after hardening and transfer to field conditions was studied using 11 phenotypic (biometric) characters and 21 simple sequence repeat (SSR) markers. The regenerative potential of cryopreserved SM was compared with two types of routinely employed explants of banana germplasm: in vitro-raised single-shoot meristems (IVM) and proliferating meristems (PM). The regeneration frequency of SM was high (60.0?±?11.5%) and statistically comparable to PM (68.3?±?4.4%) and IVM (55.6?±?11.1%) after using the droplet vitrification cryopreservation technique. The total time required for cryopreserving plants from SM (～2 mo) was substantially less than that for PM (14 mo) and IVM (8 mo). The SSR profiles of plants recovered from cryopreserved PM, IVM, and SM and compared with control plants had a similarity coefficient of 0.92. Data on phenotypic traits revealed that cryopreserved plants were statistically comparable to the mother plants raised from suckers for all important growth and yield parameters. This study broadens the possibilities to cryopreserve Musa germplasm, by applying the droplet vitrification method to a new type of explant, the SM. The results presented in this paper show that Musa meristems can be effectively cryopreserved for storage and regeneration of true-to-type plants.     

Comparison of two PVS2-based procedures for cryopreservation of commercial sugarcane (<Emphasis Type="Italic">Saccharum</Emphasis> spp.) germplasm and confirmation of genetic stability after cryopreservation using ISSR markers

Conservation of Saccharum spp. germplasm as ex situ collections of plants has a high cost, and in natural conditions, the plants remain exposed to pests, pathogens, and natural disasters. Long-term preservation of plant germplasm is important for agricultural biodiversity and food safety, so the aim of this study was to develop a cryogenic procedure for cryopreservation of sugarcane germplasm. The first study compared droplet vitrification and encapsulation-vitrification techniques for cryopreservation of in vitro shoot tips of Saccharum spp. variety Halaii. The best regeneration rate (70.9%) was obtained from 45-min PVS2 vitrification solution-treated shoot tips via the droplet vitrification technique. This technique was tested on two other Saccharum sp. varieties, and the best regeneration rates for varieties NG 57-024 and H 83-6179 were 63.3 and 76.3%, respectively. Shoots derived from cryopreserved shoot tip buds developed well-formed roots, and were easily acclimated to greenhouse conditions. The second study evaluated genetic stability of the cryopreserved varieties using ten inter-simple sequence repeat primers. A total of 211 (Halaii), 198 (H83-6179), and 201 (NG 57-024) reproducible bands, ranging from 125 to 5500 bp, were scored with this technique. One hundred genetic stability was detected from Halaii and H 83-6179 whereas 98.5% genetic stability was detected from varieties of NG 57-024. The PCR reactions showed that there was no crucial variation on genetic stability for all cryopreserved varieties.     

An optical multifrequency phase-modulation method using microbeads for measuring intracellular oxygen concentrations in plants

A technique has been developed to measure absolute intracellular oxygen concentrations in green plants. Oxygen-sensitive phosphorescent microbeads were injected into the cells and an optical multifrequency phase-modulation technique was used to discriminate the sensor signal from the strong autofluorescence of the plant tissue. The method was established using photosynthesis-competent cells of the giant algae Chara corallina L., and was validated by application to various cell types of other plant species.     

Uronic acid sequence in alginate from different sources

Alginate may be considered as a block co-polymer of D-mannuronic and L-guluronic acids, and consists of three types of blocks: homopolymeric blocks of mannuronic acid (MM) and of guluronic acid (GG), and blocks with an alternating sequence (MG). The block composition of alginates has been characterized by a simple chemical method involving partial hydrolysis with acid, followed by fractional precipitation of the acid-resistant part of the alginate. Alginates from eleven different species of brown algae have been examined and, for five species, alginates from different tissues have been compared. The results indicate that young tissue is rich in MM blocks, and that the difference between the alginates from different species is mainly due to the alginates from the older parts of the plants. Extracellular alginates from two types of bacteria have been examined.