板栗愈伤组织的诱导

通过组织培养技术,研究了不同基本培养基、不同外植体、不同植物生长物质对板栗品种韶栗18号愈伤组织诱导的影响;结果表明,韶栗18号的适宜培养基为WPM 0．5mg／L6-BA 0．2mg／LNAA,以其胚培养的诱导率较高,成愈率为79．0％。     

红松愈伤组织诱导的初步研究

以未成熟和成熟合子胚为外植体进行了红松愈伤组织的诱导,其结果表明,成熟胚的诱导效果明显好于幼胚;鉴于诱导产生褐化的主要部位来自胚根,所以外植体应选用子叶、胚轴或去除胚根的胚;诱导培养基采用LM＋2,4-D2．0mg／L＋6-BA0．5mg／L可诱导出较大量Ⅱ型有效愈伤组织,经组织学观察,可见早期原胚团,疑似胚性愈伤组织;继代增殖培养基可采用LM＋2．4-D0．5mg／L＋6-BA0．2mg,／L。     

锥栗成熟胚离体培养初报

以锥粟的胚为外植体．进行组织培养试验。结果表明：White为锥粟最适基本培养基．BA1．5mg／L和IBA 0．5mg／L为锥栗芽分化的最佳激素组合,VB1．0mg／L和GA 1．0mg／L对锥栗的壮茼培育有显著作用,活性炭(AC 1．5％)对锥粟的褐变有很强的抑制作用。锥栗胚的芽分化最佳培养基是White BA 1．5mg／L IBA 0．5mg／L VB 0．5mg／L GA 1．0mg／L AC 1．5％。     

油茶组织培养繁殖技术初步研究

以油茶（Camellia oleifera）种子胚芽和2a生扦插苗带侧芽的嫩枝作外植体进行组织培养技术研究。结果表明：适合油茶种子胚芽诱导的培养基为MS＋6-BA2．0mg／L．4-NAA0．2mg／L＋GA31．0mg／L＋蔗糖30g／L＋卡拉胶6．5g／L,适宜的增殖培养基为MS＋6-BA1．5mg／L＋NAA0．1mg／L＋GA31．0mg／L＋蔗糖30g／L＋卡拉胶6．5g／L,增殖倍数为3．50;适合油茶不定芽诱导的培养基为MS＋6-BA1．5mg／L＋IAA2．0mg／L＋GA,1．0mg／L＋蔗糖30g／L＋卡拉胶6．5g／L,适宜的增殖培养基为MS＋6-BA2．0mg／L＋IAA1．0mg／L＋GA,1．0mg／L＋蔗糖30g／L＋卡拉胶6．5g／L,增殖倍数为3．96。木质化程度已较高的油茶组培茎芽适宜的生根基质为细沙,生根率达95％。     

丽格海棠外植体筛选和培养的研究

以丽格海棠为试材,研究了不同外植体、不同生长素及大量元素含量对不定芽分化和试管苗生根的影响。结果表明,适宜丽格海棠组织培养的外植体为花梗,其次为叶片;适宜不定芽增值的培养基为MS＋BA1．0mg／L＋NAA0．1mg／L＋食糖30g／L＋琼脂8g／L,pH5．8;适宜试管苗生根的培养基为1／2MS＋IBA 0．1mg／L＋食糖30g／L＋琼脂8g／L,pH5．8,在培养后期,为获得壮苗可改用MS＋IBA 0．1mg／L＋NAA 0．1mg／L＋食糖30g／L＋琼脂8g／L。     

内蒙古几个沙地土壤理化性状调查研究

本文对内蒙古科尔沁沙地、浑善达克沙地和库布齐沙漠土壤理化性质进行了调查研究。结果表明：在土壤0～60cm土层范围内,库布齐沙漠土壤容重平均为1．45g／cm^3,科尔沁沙地为1．50g／cm^3。科尔沁沙地各类土壤平均养分含量分别为：全氮0．042％,全磷0．018％,全钾2．706％,速效磷3．274mg／kg,速效钾35．190mg／kg,有机质9．095g／kg,pH值7．5;在库布齐沙漠：全氮0．014％,全磷0．035％,全钾1．808％,速效磷1．353mg／kg,速效钾67．360mg／kg,有机质平均含量为6．216g／kg,pH值为9;在浑善达克沙地：速效磷4．032mg／kg,速效钾67．247mg／kg,有机质含量为7．450g／kg,pH值为7．5。土壤微生物在沙地土壤养分循环过程中具有重要的作用,土壤真菌、放线菌、细菌平均数量在库布齐沙漠分别为：2．4×10^3个／g（土）、1．8×10^5个／g（土）和1．8×10^6个/g（土）;科尔沁沙地分别为：6．6×10^4个／g（土）、3．8×10^5个／g（土）、1．3×10^6个／g（土）。在土壤微生物群落结构中,细菌大约占73．5％-91．9％,放线菌约占7．8％-22．5％,真菌数量最小。土壤有机质含量是影响微生物数量的主要因子,二者间具有良好的线性相关关系。     

绒毛白蜡成熟胚和茎段培养繁殖体系的建立

以绒毛白蜡成熟胚和茎段为外植体，研究了培养基、激素组合对繁殖系数和生长的影响，适合绒毛白蜡离体繁殖的培养基为WPM培养基，胚萌发率为100％，4—5天萌发成幼苗；最适分化培养基为MS＋BA4．0．6．0mg／L＋NAA2．0mg／L，分化率为39．29％，平均增殖系数为3．59；生根培养基为1／2MS＋IBA1．5mg／L，生根率达65．0％。     

铁皮石斛种子组织培养研究

通过筛选铁皮石斛（Dendrobium candium）果实的最佳消毒方法、种子发芽和壮苗生根的最适培养基,从而达到提高铁皮石斛组织培养的增殖系数和试管苗质量的目的。结果表明：用0．1％的氯化汞溶液对铁皮石斛成熟果实消毒15 min,种子污染率最低,为10％;用1／2MS ＋水解酪蛋白1 g／L ＋马铃薯粉碎液100 g／L ＋蔗糖20 g／L ＋NAA 0．5 mg／L 的培养基进行种子培养,有利于铁皮石斛芽苗的生长,诱导芽苗数达5～6千芽／果;培养基1／2MS ＋水解酪蛋白1 g／L ＋马铃薯粉碎液100 g／L ＋蔗糖20 g／L ＋6-BA 0．5 mg／L,有利于铁皮石斛原球茎的增殖,且诱导原球茎数达6～7千个／果;铁皮石斛的最佳壮苗生根培养基为花宝1号1 g／L ＋花宝2号1 g／L ＋MS 铁盐＋MS 维生素＋NAA 0．2 mg／L ＋水解酪蛋白1 g／L ＋蔗糖20 g／L＋香蕉粉碎液50 g／L ＋苹果粉碎液30 g／L ＋活性炭2 g／L,植株苗高达3～6 cm,根系数量有7～18条／丛。     

喜树组织培养初步研究

以喜树(Camptotheca cuminata Decne)的离体胚作为外植体，探讨了不同基本培养基和不同激素配比对喜树组织培养与快速繁殖的影响，从而筛选出建立喜树无性系的最优培养基配方。结果表明：幼胚萌发培养基以MS(不加任何激素的MS培养基)为佳；外植体诱导增殖培养以MS 腺嘌呤10mg/L 柠檬酸30mg／L BA2．0mg／L NAA0．1mg／L最优，其愈伤组织诱导率为95％，芽增殖系数为6．2。生根培养基以1／2MS BA0．1mg/L IBA0．3mg／L为最适，在此条件下根发育良好，生根率为80％。     

美国红栌的组织培养与快速繁殖

以美国红栌的休眠枝条和当年生嫩枝茎段为外植体进行组织培养试验。经过试验对比，筛选出红栌的最佳分化培养基为1／2MS NAA1．0rag／L 6—BA0．8mg／L，生根培养基为1／2MS IBA1．5mg／L Sugar20g／L Agar6g／L，生根率分别达到85％、100％。     

天山云杉体细胞胚的成熟及萌发条件

【目的】建立天山云杉体细胞胚成熟及萌发阶段的适宜培养条件,为该树种的体细胞胚大规模繁殖和工厂化生产提供基础。【方法】以天山云杉成熟合子胚为外植体所诱导形成的胚性愈伤组织为材料,通过14个株系、4种成熟培养基、接种量(100、150、200mg的新鲜胚性愈伤组织)、ABA浓度(1.9、3.8、7.6、19、38μmol·L^-1)等体细胞胚成熟培养条件,以及对不同起源(体细胞胚、合子胚和种子)的幼苗形态特征的比较,筛选出最优的天山云杉体细胞胚成熟与萌发条件。采用SPSS18.0等统计软件对体细胞胚进行统计分析。【结果】1)天山云杉14个株系诱导体细胞胚的结果表明,不同株系在同一成熟培养基上诱导体细胞胚的数量存在差异;其中4个株系及其接种量对体细胞胚形成数量影响的结果表明,不同株系及其接种量诱导体细胞胚的数量也存在差异,当接种量为100mg时,T36株系的体细胞胚诱导数量最高,为3470±546个,显著高于其他接种量和株系(P<0.05)。2)在4种不同成熟培养基上,均形成了成熟的体细胞胚,在1/2BLG+30g·L^-1麦芽糖培养基上形成的体细胞胚数量高于其他培养基,分别为2044个(T6株系)和2282个(T36株系),且与其他培养基差异显著(P<0.05)。3)不同ABA浓度对天山云杉体细胞胚诱导数量的影响无显著性差异(P>0.05),在ABA浓度为1.9~38μmol·L^-1时,其体细胞胚平均诱导数量为2850~2913个,其中以7.6μmol·L^-1ABA的浓度处理效果较好,平均获得2913个正常体细胞胚,高于其他处理。4)将不同起源(体细胞胚、合子胚和成熟种子)萌发的小植株进行对比,结果表明,体细胞胚和合子胚幼苗发育阶段基本一致,但合子胚的幼苗比体细胞胚的幼苗约大1倍,但二者间差异不显著(P>0.05);体细胞胚与合子胚子叶的平均数量一致,二者无显著差异(P>0.05),多数幼苗子叶数量为7~8个。【结论】天山云杉体细胞胚成熟阶段的适宜培养条件为胚性愈伤组织接种量100mg,1/2BLG培养基添加7.6μmol·L^-1的ABA及75%PEG4000、30g·L^-1麦芽糖,并添加750mg·L^-1的L-谷氨酰胺或50mg·L^-1L-天冬酰胺。不同株系在诱导体细胞胚的数量上存在差异。体细胞胚再生植株与合子胚植株在形态上相似。研究结果可为天山云杉体细胞胚的大规模繁殖和工厂化生产提供基础。     

离体条件下西黄松成熟合子胚不定芽的诱导及植株再生

以西黄松成熟胚为外植体诱导不定芽,在GD 9.85～19.70 μmol·L'-1 6-BA 0.0～14.42 μmol·L-1 NAA上不定芽诱导率最高达65.8%,平均增殖率为7,最大增殖率达10;不定芽形成有2种途径,即子叶直接形成不定芽和子叶组织再分化形成不定芽;NAA不利于外植体不定芽的诱导;不定芽的生长和扩繁采用不加生长调节剂的1/2 GD和1/2 SH培养基;培养基中加入适量的活性炭有利于不定芽和根的生长.不定嫩梢在1/2 GD和1/2 SH附加不同浓度NAA和GA,3的培养基上进行生根诱导,试验结果表明:NAA对不定根的形成起主要作用,在1/2 GD 28.84 μmol·L'-1 NAA 4.17 μmol·L'-1 GA,3培养基中不定梢的生根率为16.7%.在离体培养条件下,以西黄松成熟胚为外植体获得了再生植株.     

Effect of parent genotype on somatic embryogenesis in Scots pine (Pinus sylvestris)

Controlled crosses of seven Scots pine (Pinus sylvestris L.) trees produced 49 families that included both reciprocals and selfings. Embryogenic cultures were initiated from immature megagametophytes and after 6 months in maintenance culture, mature somatic embryos were produced from the surviving 166 lines. The effect of parent genotypes on the cultures was evaluated at initiation of the tissue culture period, after 6 months in maintenance culture and at embryo maturation. The effect of the maternal parent was most pronounced at culture initiation. After 6 months in tissue culture, the maternal effect had decreased and the effects of both parents were significant. By the somatic embryo maturation stage, the maternal effect was still considerable but the paternal effect was no longer detectable. There was little correlation between the ranking of mothers and fathers, indicating that the maternal effect was caused by factors other than the paternal effect. No mother x father interaction was found, indicating that mothers successful at initiation and after 6 months in tissue culture, pollinated by any of the successful fathers, produced somatic lines and mature somatic embryos.     

Seasonal changes in above- and belowground carbohydrate concentrations of ponderosa pine along a pollution gradient

Seasonal patterns of carbohydrate concentration in coarse and fine roots, stem or bole, and foliage of ponderosa pine (Pinus ponderosa Laws) were described across five tree-age classes from seedlings to mature trees at an atmospherically clean site. Relative to all other tree-age classes, seedlings exhibited greater tissue carbohydrate concentration in stems and foliage, and greater shifts in the time at which maximum and minimum carbohydrate concentration occurred. To determine the effect of environmental stressors on tissue carbohydrate concentration, two tree-age classes (40-year-old and mature) were compared at three sites along a well-established, long-term O3 and N deposition gradient in the San Bernardino Mountains, California. Maximum carbohydrate concentration of 1-year-old needles declined with increasing pollution exposure in both tree-age classes. Maximum fine root monosaccharide concentration was depressed for both 40-year-old and mature trees at the most polluted site. Maximum coarse and fine root starch concentrations were significantly depressed at the most polluted site in mature trees. Maximum bole carbohydrate concentration of 40-year-old trees was greater for the two most polluted sites relative to the cleanest site: the bole appeared to be a storage organ at sites where high O3 and high N deposition decreased root biomass.     

Influence of drought stress and low irradiance on plant water relations and structural constituents in needles of Pinus ponderosa seedlings

The influence of low light on tolerance to prolonged drought was tested on unshaded and shaded seedlings of ponderosa pine (Pinus ponderosa var. scopulorum Dougl. ex Laws.). Unshaded seedlings of P. ponderosa var. ponderosa were also drought stressed to compare varietal responses to drought. The maximum irradiance received by shaded seedlings was 10% of full light. Seedlings were progressively drought stressed until predawn water potentials (Psi(x)) were -5.0 MPa. Relative water content (RWC) and the reciprocal of Psi(x) were analyzed by means of an unusual application of the pressure-volume relationship for determination of RWC of the apoplast (RWC(a)), osmotic potential at full turgor (Psi(oft)), and ratio of fully turgid weight to dry weight. Major varietal differences in drought response were in RWC(a) and needle cellulose content. The shaded seedlings showed tissue damage at relative water contents < 60%, and were killed by water deficits from which unshaded seedlings recovered. Correspondingly, shaded plants had significantly higher cell volume/cell mass ratio, Psi(oft), less cellulose in needle tissue, and lower RWC(a) than unshaded plants. These differences suggest that low irradiance restricts drought adaptation in ponderosa pine.     

Polyamines in embryogenic cultures of Norway spruce (Picea abies) and red spruce (Picea rubens)

Embryogenic cultures of red spruce (Picea rubens Sarg.) and Norway spruce (Picea abies (L.) Karst.) were initiated from dissected mature zygotic embryos. The tissues were grown on either proliferation medium or maturation medium. On proliferation medium, the embryogenic tissue continued to produce early stage somatic embryos (organized meristems attached to elongated, suspensor-like cells), whereas on maturation medium fully mature embryos developed from the embryonic tissue. Analysis of polyamines in tissues grown on these two media showed that: (1) both putrescine and spermidine concentrations were always higher in cultures grown on proliferation medium than in cultures grown on maturation medium; (2) in both species, spermidine concentrations declined with time in the tissues grown on maturation medium; and (3) spermine was present in only minute quantities and showed only a small change with time. The presence of difluoromethylornithine in the culture medium had little effect on polyamine concentration, whereas the presence of difluoromethylarginine caused a decrease in putrescine concentrations in both red spruce and Norway spruce tissues grown on proliferation medium or maturation medium.     

Organogenesis and embryogenesis in mature zygotic embryos of Picea sitchensis

Differentiation of adventitious buds and somatic embryos from mature zygotic embryos of Picea sitchensis (Bong.) Carr. is described. Adventitious buds were formed on embryos pulse-treated with 250 microM benzyladenine for 2 h and cultured on medium lacking growth regulators. Buds were initiated at different frequencies and sites depending on when the BA-pulsed embryos were transferred to fresh culture medium. Embryogenic callus was formed when the zygotic embryos were cultured on medium containing 10 microM 2,4-dichlorophenoxyacetic acid and 5 microM benzyladenine. Although 50% of the embryos gave rise to embryogenic callus, only 20% of the callus continued to proliferate after subculture. Proliferation of new somatic embryos occurred from both the embryonic region and the suspensor region on previously formed somatic embryos. The pattern for development of adventitious buds and somatic embryos in Picea sitchensis is compared to that in Picea abies under similar culture conditions.     

枣树胚离体培养的研究

本文对影响枣树胚离体培养的三个因素：取材时期，激素配方，及光照条件进行了研究，结果表明：发育早期较为幼嫩的胚，主要的培养产物是绿色或黄色的愈伤组织及胚状体，不能直接发育为小植株，成熟胚萌发率较高，添加外源激素起抑制作用。不能诱导产生愈伤组织及胚状体，光照可以明显的诱导胚萌发，而且这种诱导作用主要在培养的初期。     

美国黄松与油松生长特性的比较研究

以陕西榆林黑龙潭树木园引种的美国黄松和油松为研究对象,结合延安树木园的一些情况,对2个树种进行了比较,研究了生长进程和生长性状的相关性,并对其适应性进行了阐述。研究结果表明,18年生美国黄松与油松在生长量上有差异,但未达到显著水平。2个树种的高生长进程表现为一致,第7年进入速生阶段,年生长量达到40 cm以上。在树高、胸径和材积3个生长指标上,美国黄松具有很好的相关性,相关系数均在0.9以上;而油松的树高与胸径相关系数仅为0.583。对于黑龙潭山地树木园而言,油松和美国黄松都是外来树种。18年引种结果表明,2个树种引入该地后成活率高、生长量大、适应性强,具有较高的引种推广价值。     

红豆杉及南方红豆杉体细胞胚胎发生的研究

利用江西的红豆杉（Ｔａｘｕｓｃｈｉｎｅｎｓｉｓ）、福建的南方红豆杉（Ｔａｘｕｓｃｈｉｎｅｎｓｉｓｖａｒ．ｍａｉｒｅｉ）以及四川的南方红豆杉（Ｔａｘｕｓｃｈｉｎｅｎｓｉｓｖａｒｍａｉｒｅｉ）的成熟胚为试验材料,成功地诱导出大量的愈伤组织。这３种材料愈伤组织的最高诱导频率分别为９５７％、９８４％、９１７％。细胞学和形态学的观察结果表明：在适当的条件下经过一段时间的培养,这些愈伤组织能够产生处在不同发育阶段的体细胞胚。上述３种植物材料每１００块愈伤组织平均最多分别可产生１２７、９１和３３个体细胞胚。