曼地亚红豆杉‘Hicksii’花粉活力检测条件优化和适宜诸藏温度分析

采用单因素实验设计对适宜于曼地亚红豆杉‘Hicksii’(Taxus media‘Hicksii')花粉活力检测的TTC染色法和离体培养法的实验条件进行了选择,并采用优化条件研究了在25℃～-196℃条件下储藏13周花粉活力的变化.结果表明:采用TTC染色法测定的花粉活力均高于离体培养法.在TTC染色法的3个影响因素(染液pH、TTC浓度和染色温度)中,染液pH对检测结果有极显著影响,而染色温度和TTC浓度则无显著影响,但温度对染色速率有影响.在离体培养法的3个影响因素(培养基中蔗糖添加量、H3BO3和Ca(NO3)2浓度及培养温度)中,蔗糖添加量对检测结果有极显著影响,在含质量体积分数15％蔗糖的培养基上花粉活力最高,而在含质量体积分数20％和25％蔗糖的培养基上花粉均不能萌发;在含100和200 mg ·L-1H3BO3的培养基中添加200 mg·L-1Ca(NO3)2均能显著提高花粉活力;培养温度对花粉萌发速率有影响但对花粉活力没有明显影响.TTC染色法的最优检测条件为:用5.0g·L-1TTC染液(pH 7.0)在35℃下染色2.0h;离体培养法的最优检测条件为:用含质量体积分数15％蔗糖、100 mg·L-1H3BO3和200 mg·L-1Ca(NO3)2的培养基暗培养4d.在25℃、4℃、0℃、-20℃、-80℃和-196℃条件下储藏13周,‘Hicksii'花粉活力和保持时间有明显差异,其中,于-80℃和-196℃储藏3d 花粉就丧失活力;于25℃和-20℃储藏7周、4 ℃储藏10周,花粉仍有一定的活力;而在0℃条件下花粉活力最高,且储藏11周花粉仍有活力.推测曼地亚红豆杉‘Hicksii’花粉对低温的抗性较差,0℃为其适宜的储藏温度.     

菊花茎尖的玻璃化超低温保存研究

本文建立了适合中国菊花种质资源长期保存的玻璃化超低温保存技术体系.在4℃下,把1～2mm的菊花茎尖放在含0.4mol/L蔗糖的MS培养基上暗培养2～3d,用预处理液在25℃下处理30min,再用玻璃化试剂PVS2在冰浴条件下处理15min,换新鲜的PVS2试剂并迅速投入液氮.液氮保存24h后,40℃水浴解冻2min,用含蔗糖1.2mol/L的MS液体培养基洗涤20min,滤纸吸干后接种到恢复培养基中,在25℃条件下弱光培养1～3d转入正常光照培养条件下培养,2周后成活率可达86%以上,成活的茎尖均可再生.     

小滴玻璃化法脱除蝴蝶兰种苗建兰花叶病毒的研究

以感染建兰花叶病毒(Cymbidium mosaic virus,CymMV)的蝴蝶兰(Phalaenopsis aphrodite)品种‘满天红’为试材,通过筛选蔗糖预培养浓度、预培养时间、PVS2(Plant vitrification solution 2,PVS2)处理时间三个关键因素,建立蝴蝶兰茎尖小滴玻璃化超低温脱毒体系,将再生的茎尖诱导类原球茎,再分化成苗,经RT-PCR检测CymMV的脱除情况,阴性结果的再生植株进行增殖和诱导生根。结果显示:最佳预培养为:BM+0.6 mol·L-1蔗糖处理1~2 d,超低温茎尖的成活率为70%~76.7%,再生率为53.3%~56.7%;PVS2最佳处理时间为60~90 min,超低温茎尖的成活率为73.3%~76.7%,再生率为50.0%~56.7%。再生植株经RT-PCR检测,CymMV的脱除率为50%。该研究为兰科植物脱除CymMV提供了理论和技术基础。     

药用植物黄芪离体培养茎尖的包埋脱水法和包埋玻璃化法超低温保存（英文）

为找出一条黄芪种质长期包埋脱水法保存和包埋玻璃化法保存的程序,以来源于黄芪离体生长腋芽的黄芪茎尖并包埋成海藻酸钙珠。随后,在MS+0.75 mol·L~(-1)蔗糖的液体培养基中25℃下预培养5 d后,放于干硅胶上无菌干燥5 h,直至含水量达23.1%(以鲜重为基础)时将材料投入液氮保存。保存1 d后,茎尖在40℃水浴中化冻2~3 min并转入固体培养基上进行再生培养,2周后大约50%的茎尖可再生出芽。黄芪茎尖包埋玻璃化法超低温保存程序也被优化,同样包埋成海藻酸钙凝胶珠的茎尖在MS+1 mg·L~(-1)6-BA+0.05 mg·L~(-1)NAA+0.75 mol·L~(-1)蔗糖的液体培养基中25℃预培养3 d,用2 mol·L~(-1)甘油+0.4 mol·L~(-1)蔗糖装载液25℃装载90 min并再用PVS2在0℃下处理120 min后直接投入液氮。保存1 d后,取出材料在37℃水浴中化冻2~3 min,并用MS+1 mg·L~(-1)6-BA+0.05 mg·L~(-1)NAA+1.2 mol·L~(-1)蔗糖的液体培养基进行10 min的洗涤后转入MS+1 mg·L~(-1)6-BA+0.05 mg·L~(-1)NAA的固体培养基上进行再生培养。茎尖的再生率接近80%。以上两种超低温保存方式均未造成再生植株形态学上的变化。因此,包埋脱水法和包埋玻璃化法两种常规方法对于黄芪茎尖超低温保存来说均具有重要的意义。     

25-羟基胆甾醇对鸡原始生殖细胞增殖的影响

本研究为了优化现有的鸡PGCs(原始生殖细胞)的培养系统,为今后研究生殖细胞发育与生产转基因鸡奠定良好基础。分别用含0μmol/L(对照组)、0.1μmol/L、0.5μmol/L、1.0μmol/L 25-羟基胆甾醇的培养液培养鸡PGCs,5 d后细胞计数检测其细胞增殖情况。与对照组(不添加25-羟基胆甾醇的鸡PGCs培养液)相比,0.1μmol/L处理组细胞数目没有显著差异,0.5μmol/L和1μmol/L处理组细胞数目均显著增加。对1.0μmol/L 25-羟基胆甾醇处理的鸡PGCs用RT-PCR、细胞免疫染色、细胞注射迁移的方法检测处理后的生物学特性,发现处理后的鸡PGCs仍然保持正常的生殖细胞生物学特性。本研究表明25-羟基胆甾醇能有效的促进鸡P GCs的增殖,且不改变鸡PGCs的生物学特性。     

德昌杉的组织培养

植物名称:德昌杉(Cunninghamia unicanalicu-lata) 材料类别:茎尖培养条件:以1/2MS为基本培养基,附加:(1)BA0.75～1mg/L(单位下同) IBA0.5 蔗糖3％ 活性炭2g/L;(2)IBA1.5 NAA0.5～0.75 蔗糖2％。琼脂0.7％,pH5.8～6.0。温度23±     

植物资源开发利用新信息——国外有关植物的专利摘要(十二)

331.提高小麦抗寒和抗旱能力的化合物 据前苏联1991年专利记载。氨基甲酰衍生物2-硫代螺环已基乙内酰脲可提高小麦抗寒和抗旱能力。专利说明对此化合物的化学结构和制备作了叙述。 332.马铃薯茎尖无病毒培养 据前苏联1991年专利记载。马铃薯茎尖为马铃薯植株无病毒部分,用含有分枝甘露聚糖0.15—0.25g/L、氨基胍0.05g/L和三嗪衍生物0.05g/L的vanGoff培养基培养1.5—2天,即可用为无病毒马铃薯种薯繁殖。     

葡萄细胞悬浮培养体系的建立和优化

为了利用葡萄愈伤组织建立快速稳定的葡萄细胞悬浮体系,以无核白和黑比诺葡萄无菌幼苗的茎段、叶片以及叶柄为外植体,通过基本培养基、不同植物生长调节剂配比及其浓度、PVP等优化疏松型愈伤组织的诱导方法并建立稳定的细胞悬浮培养体系。结果表明,以无核白和黑比诺葡萄茎段为外植体,在添加2.0 mg/L NAA和0.3 mg/L 6-BA的MS培养基上适合疏松型愈伤组织的诱导。以B5为基本培养基添加1.0 mg/L 2,4-D和0.5 mg/L 6-BA以及0.2%PVP的优化培养条件下,建立了快速稳定的无核白葡萄悬浮培养体系。葡萄悬浮培养细胞生长曲线呈S形,接种后6-18 d处于对数生长期,第21天细胞增长量达到最大值。细胞活力测定与TTC染色结果一致表明,接种后培养9 d细胞活力最强。建立了快速稳定的无核白葡萄悬浮培养体系,选择细胞活力最强且细胞快速增值的对数期7-9 d的细胞进行葡萄悬浮细胞遗传转化,效率较高。     

四倍体石刁柏的组织培养和快速繁殖

1 植物名称石刁柏(Asparagus officinalis)。 2 材料类别二倍体“UC72”品种种子经秋水仙素溶液处理诱导成四倍体的侧枝茎尖。 3 培养条件芽分化培养基为:(1)MN+NAA 0.1 mg/L(单位下同)+BA 0.1,蔗糖3％,琼脂0.6％;(2)MS+NAA0.1+BA0.05,蔗糖3％,琼脂0.6％;生根培养基为(3)MS+NAA 5.0+BA 0.05,蔗糖4％的液体培养基(内有海绵碎块作支撑物,下同):     

羽叶薰衣草的组织培养与快速繁殖

1植物名称羽叶薰衣草(Lavandula pinnata L.)。2材料类别茎尖或腋芽的茎段。3培养条件不定芽诱导和增殖培养基:(1)MS 6- BA 0.5 mg·L~(-1)(单位下同);(2)MS 6-BA 1.0。生根培养基:(3)MS NAA 0.2 0.1%的活性碳;(4) 1/2MS IBA 0.2 0.1%的活性碳。以上培养基均加入3%的蔗糖和0.6%的琼脂,pH 5.8。培养温度25～28℃,光照强度27～36μmol·m~(-2)·s~(-1),光照时间12h·d~(-1)。     

Cryopreservation of shoot tips from in vitro plants of sweet potato [Ipomoea batatas (L.) Lam.] by vitrification

 Routine cryopreservation of shoot tips from sweet potato [Ipomoea batatas (L.) Lam] has been hampered by their survival variability after cryogenic exposure. We examined the effects of light conditions on stock plants, sucrose preculture and cryoprotectant loading on survival after vitrification using PVS2 solution. The survival of vitrified sweet potato shoot tips cooled to approximately –208  °C was increased by preculturing with 0.3 M sucrose for 24 h at 22  °C. Survival was also enhanced by excising shoot tips immediately after the 8-h dark photoperiod. The best survival after cryogenic exposure was obtained using 2 M glycerol +0.4 M sucrose for 1 h at 22  °C followed by dehydration with PVS2 for 16 min at 22  °C. Rapid cooling was used and achieved by the immersion of foil strips into partially solidified nitrogen. Successfully vitrified and warmed shoot tips directly developed shoots on a medium containing 1 μM NAA, 0.5 μM BA and 0.1 μM kinetin with only minimum callus formation. Shoot formation occurred in all surviving shoot tips. This procedure shows promise for cryopreserving sweet potato shoot tips. Received: 2 March 1999 / Revision received: 21 September 1999 / Accepted: 29 September 1999     

Cryopreservation of Shoot Tips of Tetraploid Potato (Solanum tuberosumL.) Clones by Vitrification

In vitro-grown shoot tips of five tetraploid potato (SolanumtuberosumL.) clones were cryopreserved by vitrification. Excisedshoot tips (0.5–0.7 mm) were pre-cultured on filter paperdiscs over half strength liquid Murashige and Skoog (MS) mediumsupplemented with 8.7 µMGA₃and different combinationsof sucrose (0.3, 0.5 and 0.7M) plus mannitol (0, 0.2 and 0.4M)for 2 d under a 16 h photoperiod at 24 °C. The pre-culturedshoot tips were either successively loaded with 20 and 60% PVS2 solutions or directly exposed to concentrated vitrificationsolution before physical vitrification during liquid nitrogentreatment. The vitrified shoot tips were warmed rapidly andtreated with dilution mixture (MS+1.2Msucrose) for 30 min beforeplating on regrowth medium. Addition of mannitol to the pre-culturemedium improved survival of vitrified shoot tips. Direct dehydrationof pre-cultured shoot tips with concentrated PVS 2 was detrimentalto survival of vitrified shoot tips. Shoot tips pre-culturedon medium containing 0.3Msucrose plus 0.2Mmannitol, and loadedwith 20% PVS 2 for 30 min followed by 15 min incubation in 60%PVS 2 and 5 min incubation in 100% PVS 2 at 0 °C resultedin up to 54% survival after vitrification. About 50% of vitrifiedand warmed shoot tips formed shoots directly. Post-thaw culturingof vitrified shoot tips on medium containing an elevated levelof sucrose (0.2M) under diffuse light for the first week enhancedthe survival rate. Continuous culturing of vitrified shoot tipson high-sucrose medium induced multiple shoot formation.Copyright1998 Annals of Botany Company Solanum tuberosumL., potato, cryopreservation, germplasm conservation,in vitroconservation, meristems, shoot tips, tissue culture, vitrification.     

Simplified cryopreservation of sweet potato [<Emphasis Type="Italic">Ipomoea batatas</Emphasis> (L.) Lam.] by optimizing conditions for osmoprotection

Shoot tips of sweet potato were successfully cryopreserved using an encapsulation vitrification method. Encapsulated shoot tips were pre-incubated in liquid Murashige-Skoog medium containing 30 g/l sucrose for 24 h, then precultured in sucrose-enriched medium (0.3 M sucrose) for 16 h. Shoot tips were osmoprotected with a mixture of 2 M glycerol and 1.6 M sucrose for 3 h before being dehydrated with a highly concentrated vitrification solution (PVS2) for 1 h at 25 degrees C. The encapsulated and dehydrated shoot tips were transferred to a 2 ml cryotube, suspended in 0.5 ml PVS2, and plunged directly into liquid nitrogen. Rapidly warmed shoot tips developed normal shoots and roots in 21 days without any morphological abnormalities after plating on a recovery medium. High levels (average of about 80%) of shoot formation were obtained for three cultivars of sweet potato. This encapsulation vitrification method appears promising for cryopreservation of sweet potato germplasm.     

Cryopreservation of sour orange (Citrus aurantium L.) shoot tips

Summary The objective of this study was to establish a cryopreservation protocol for sour orange (Citrus aurantium L.). Cryopreservation was carried out via encapsulation-dehydration, vitrification, and encapsulation-vitrification on shoot tips excised from in vitro cultures. Results indicated that a maximum of 83% survival and 47% regrowth of encapsulated-dehydrated and cryopreserved shoot tips was obtained with 0.5M sucrose in the preculture medium and further dehydration for 6 h to attain 18% moisture content. Dehydration of encapsulated shoot tips with silica gel for 2h resulted in 93% survival but only 37% regrowth of cryopreserved shoot tips. After preculturing with 0.5M sucrose, 80% of the vitrified cryopreserved shoots survived when 2M sucrose plus 10% dimethyl sulfoxide (DMSO) was used as a cryoprotectant for 20 min at 25°C. Survival and regrowth of vitrified cryopreserved shoot tips were 67% and 43%, respectively, when 0.4M sucrose plus 2M glycerol was used as a loading solution followed by application of 100% plant vitrification solution (PVS2) for 20 min. Increased duration of exposure to the loading solution up to 60 min increased survival (83%) and regrowth (47%) of cryopreserved shoot tips. With encapsulation-vitrification, dehydration with 100% PVS2 for 2 or 3 h at 0°C resulted in 50 or 57% survival and 30 or 40% regrowth, respectively, of cryopreserved shoot tips.     

Cryopreservation of in vitro-grown shoot tips of grapevine by encapsulation-dehydration

In vitro-grown shoot tips of the LN33 hybrid (Vitis L.) and cv. Superior (Vitis vinifera L.) were successfully cryopreserved by encapsulation-dehydration. Encapsulated shoot tips were precultured stepwise on half-strength MS medium supplemented with increasing sucrose concentrations of 0.25, 0.5, 0.75 and 1.0 M for 4 days, with one day for each step. Following preculture, encapsulated shoot tips were dehydrated prior to direct immersion in liquid nitrogen for 1 h. After thawing, cryopreserved shoot tips were post-cultured on a post-culture medium for survival. An optimal survival of cryopreserved shoot tips was achieved when encapsulated shoot tips were dehydrated to 15.6 and 17.6% water content for the LN33 hybrid and cv. Superior, respectively. Comparison between the effects of dehydration with silica gel and by air drying on cryopreserved shoot tips, showed that survival was dependent on water content, not on dehydration method. The thawing method markedly affected survival of cryopreserved shoot tips, and thawing at 40 °C for 3 min was found best. No callus formation and fastest shoot elongation were obtained when cryopreserved shoot tips were post-cultured on the post-culture medium composed of half-strength MS supplemented with 1 mg l⁻¹ BA and 0.1 mg l⁻¹ NAA. With these optimized parameters, 60 and 40% survival of cryopreserved shoot tips were obtained for the LN33 hybrid and cv. Superior, respectively. This revised version was published online in June 2006 with corrections to the Cover Date.     

The survival of in vitro shoot tips of Garcinia mangostana L. after cryopreservation by vitrification

This report highlights the first successful cryopreservation protocol for shoot tips of Garcinia mangostana L. achieved by using vitrification technique. We investigated the effects of different temperatures and exposure periods to a plant vitrification solution 2 (PVS2), sucrose concentrations and preculture periods, and unloading treatments in steps of the vitrification protocol on the survival of G. mangostana shoot tips after cryopreservation. Exposure to PVS2 for 25 min gave beneficial effects with 10.4 ± 1.8 % survival at 0 °C with average water content of 1.1 ± 0.3 g g^?1 dry mass. Survival was 13.7 ± 5.5 % when using preculture medium with full-strength Murashige and Skoog (MS) medium supplemented with 0.6 M sucrose for 2 days. A significant difference was observed in survival of shoot tips when treated with various sucrose concentrations in preculture which strengthens their importance towards enhancing survival of shoot tips after cryopreservation. MS with 0.4 M sucrose and 2 M glycerol applied as an unloading solution increased the survival of shoot tips to 44.1 ± 6.5 %. Experiments on the effect of ascorbic acid were also conducted for each step of vitrification. Our results showed higher survival of 45.8 ± 3.8 % but there were no significant effects compared with the control (without ascorbic acid). Further study on the recovery dark/light period was conducted. Survival of shoot tips significantly increased to 50.0 ± 16.7 % when subjected to 7 days in the dark before transferring to 16 h/8 h light/dark photoperiod. These studies strengthen suggestions that cryopreservation through vitrification is possible for ex situ conservation of germplasm of this tropical recalcitrant species.     

Plasmolysis and recovery of different cell types in cryoprotected shoot tips of Mentha × piperita

Summary. Successful cryopreservation of plant shoot tips is dependent upon effective desiccation through osmotic or physical processes. Microscopy techniques were used to determine the extent of cellular damage and plasmolysis that occurs in peppermint (Mentha × piperita) shoot tips during the process of cryopreservation, using the cryoprotectant plant vitrification solution 2 (PVS2) (30% glycerol, 15% dimethyl sulfoxide, 15% ethylene glycol, 0.4 M sucrose) prior to liquid-nitrogen exposure. The meristem cells were the smallest and least plasmolyzed cell type of the shoot tips, while the large, older leaf and lower cortex cells were the most damaged. When treated with cryoprotectant solutions, meristem cells exhibited concave plasmolysis, suggesting that this cell type has a highly viscous protoplasm, and protoplasts have many cell wall attachment sites. Shoot tip cells were most severely plasmolyzed after PVS2 treatment, liquid-nitrogen exposure, and warming in 1.2 M sucrose. Successful recovery may be dependent upon surviving the plasmolytic conditions induced by warming and diluting treated shoot tips in 1.2 M sucrose solutions. In peppermint shoot tips, clumps of young meristem or young leaf cells survive the cryopreservation process and regenerate plants containing many shoots. Cryoprotective treatments that favor survival of small, meristematic cells and young leaf cells are most likely to produce high survival rates after liquid-nitrogen exposure. Correspondence and reprints: National Center for Genetic Resources Preservation, U.S. Department of Agriculture, 1111 S. Mason Street, Fort Collins, CO 80521, U.S.A.     

Phloroglucinol enhances growth and rate of axillary shoot proliferation in potato shoot tip cultures in vitro

Efficacy of phloroglucinol in promoting growth and development of in vitro-derived shoot tips was studied in six potato (Solanum tuberosum L.) genotypes. Different concentrations of phloroglucinol (0, 0.08, 0.4, 0.8, 1.2 and 1.6 mM) were tested in combination with either 0.1 or 0.2 M sucrose in shoot tip proliferation medium based on MS (Murashige and Skoog, 1962) medium supplemented with 5.8 μM GA₃ (gibberellic acid), 1.1 μM BA (N⁶-benzyladenine) and 8.39 μM D-calcium pantothenate. Phloroglucinol fostered multiple shoot formation, promoted axillary shoot proliferation in terms of shoot tip fresh weight and shoot length, and stimulated root formation on the shoot tips. There was significant phloroglucinol × sucrose interaction for number of shoots developed per shoot tip, shoot tip fresh weight and number of roots induced per shoot tip. The beneficial effect of phloroglucinol on shoot tip survival was conspicuous only in genotypes that showed poor survival in the control proliferation medium. There were significant differences in response between the two sucrose levels with regard to shoot tip fresh weight and number of roots per shoot tip. Phloroglucinol in combination with 0.2 M sucrose induced maximum number of roots per shoot tip. Optimum shoot tip growth was fostered in medium containing 0.8 mM phloroglucinol and 0.2 M sucrose. High frequency multiple shoot formation in this medium ensures a faster rate of potato shoot tip multiplication within a limited time and space. This revised version was published online in June 2006 with corrections to the Cover Date.     

Anatomy and osmotic potential of the Vitis rootstock shoot tips recalcitrant to cryopreservation

This study was carried out on Kober 5BB (Vitis Berlandieri × V. riparia) grape rootstock shoot tips during the preparatory steps preceding the direct immersion in liquid nitrogen, in order to overcome until now unsuccessful cryopreservation with this species. The exposure of shoot tips to 0.3–0.4 M sucrose leads to a high cell solute concentration. The treatment with plant vitrification solution (PVS2) alone, i.e., not followed by storage in liquid nitrogen, markedly affected shoot tip survival. After a 30 min exposure, regrowth percentage of shoot tips decreased from 94 % (control) to 57 %, and dropped to 15 % when the treatment was prolonged up to 60 min. After a 90 min exposure, no regrowth occurred. In addition, plantlets regenerated from shoot tips which underwent 60 min or more exposure to PVS2 showed signs of malformation. Microscope observations of shoot tips treated with 0.3 or 0.4 M sucrose and 30 min PVS2 showed the presence of cells starting to plasmolyze, localized in the area surrounding the apical meristem. A limited presence of starch grains in meristem and bract cells was also noted. However, the most conspicuous consequence of prolonged PVS2 treatment was convex plasmolysis. The phenomenon was dependent on the time of PVS2 exposure. Indeed, after a 30 min treatment, plasmolysis was minimal or absent, but it increased with longer exposure to PVS2 at 4 °C.