Outdoor mass microalgae production in Bahia Kino, Sonora, NW Mexico

The diatom Chaetoceros muelleri was grown in outdoor mass cultures under the winter, spring and summer conditions of Bahia Kino, Sonora, NW Mexico. The solar irradiance in winter was close to 60% of that available in spring and summer, but the cell concentrations and the harvestable biomass were one order of magnitude higher in spring and summer than in winter. There was no difference between the biomass harvested after 2 and 3 days in winter and summer, whereas in spring it was higher after 3 days. The protein content was significantly lower in winter, and carbohydrates and lipids were higher in winter and spring. The number of cells and the amount of harvestable biomass of outdoor cultures of C. muelleri depend on the temperature prevailing in each season, which causes significant differences in growth rates and in biochemical composition.     

无籽西瓜组培脱毒与离体嫁接技术研究

利用无籽西瓜种胚进行组培脱毒与西葫芦离体嫁接研究。结果表明:不同消毒剂对种胚萌发有一定影响,其中消毒剂二氧化氯250 mg/L处理有利于种胚萌芽,萌发率达86.7%。6-BA对茎尖分化有促进作用,浓度0.2 mg/L对芽分化有显著作用;不同激素浓度对芽丛增殖和单芽生根也有一定影响,其中MS+6-BA 0.5 mg/L+IAA 1 mg/L继代培养增殖率最高;MS+NAA 0.2 mg/L生根率最高(83.9%)。采用无菌嫁接成活率(77.5%)高于开放式嫁接成活率(37.5%);经ELISA检测,对WMV-2(西瓜花叶病毒2号)、ZYMV(小西葫芦黄化花叶病毒)的脱毒率分别为75%和80%。     

家兔早期胚胎体外培养和移植研究

用ＦＳＨ，ＰＭＳＧ，ＨＣＧ和ＩＣＩ－８０９９６对２０只家兔进行超数排卵，平均每只排卵１９．１枚，回收胚胎１３．５枚。超排卵数和卵子回收数ＦＳＨ分别为２６．３枚和２１．１５枚，ＰＭＳＧ为２２枚和１３．５。将正常的２５枚１细胞，７枚２细胞和３２枚４细胞期胚胎在ＴＣＭ－１９９培养液，５％ＣＯ２和 ３８．５℃环境中培养６０－７ ０ｈ，６３．１７％的胚胎可发育至囊胚移植至５只体兔后，产出仔兔１３只。     

Studies on Genetic Transformatiom of Embryogenic Suspension Cultures of Sweetpotato

Genetic transformation of embryogenic suspension cultures of sweetpotato cv. Lizixiang wasconducted by using Agrobacterium tumefaciens strain A208SE harboring the binary vectors pROA93 with β-glucronidase (GUS) and neomycin phosphotransferase (NPT Ⅱ ) genes. The results indicated that embryogenicsuspension cultures precultured for 1 -3 d were suitable for the transformation. The optimal cocultivation timewas 4 - 5 d. The optimal concentration of kanamycin was 50-75 mg L-1 for suspension culture and 100 mg L-1for embryogenic callus proliferation and plant regeneration. The optimal concentration of carbencillin was 100mg L-1. Transgenic plants identified with GUS assays and PCR analyses were obtained.     

甘薯胚性悬浮细胞遗传转化的研究

 以甘薯品种栗子香的胚性悬浮细胞为材料 ,以A2 0 8SE(pROA93)为供体菌株 ,对甘薯胚性悬浮细胞遗传转化的基本条件进行了研究。结果表明 ,对胚性悬浮细胞预培养 1～ 3d有利于转化 ,适宜的共培养时间为 4～ 5d ,适宜的Kan浓度为 5 0～ 75mg·L-1(悬浮培养阶段 )和 10 0mg·L-1(增殖培养阶段和植株再生阶段 ) ,适宜的Carb浓度为 10 0mg·L-1。获得了经GUS检测及PCR检测的转基因植株。     

人工林场杨木材性质与生长培育关系的研究

本文以生长在 3种长江滩地类型 (江滩、洲滩、湖滩 )、3种栽植密度 ( 3m×4m ,4m× 5m ,5m× 6m)下的3个品系速生人工林杨树木材 [欧美杨无性系 72杨 (Populus×euramericacv.I -72 58) ,美洲黑杨无性系 63杨(P .deltiodescv.I-63 51 )和 69杨 (P .deltoidescv.I-69 55) ,以下简称 72杨 ,63杨 ,69杨 ]为对象 ,深入地分析了人工林杨树木材材性与生长培育之间的关系。结果表明 :( 1 )品系对滩地杨树木材材性有较大的影响。安徽新洲洲滩和湖北黄洲江滩上生长的 63杨 ,湖南沅江湖滩上生长的 72杨纤维长度最长 ,微纤丝角最小 ,导管比量最大 ,方差分析表明 :72、63、69杨微纤丝角和主要物理力学性质差异均达显著和极显著。 ( 2 )滩地类型对72、63、69杨木材材性都有或大或小的差异。方差分析表明 :63杨、69杨微纤丝角、基本密度、抗弯强度和干缩率差异显著 ,说明 63杨和 69杨受滩地类型影响较大。 ( 3)栽植密度对 72、63、69杨木材材性的影响因材性指标的不同而不同。对 72、63、69杨来讲 ,栽植密度越大 ,微纤丝角、导管比量增大 ,纤维长度、木纤维比量、木射线比量都减小 ,基本密度、抗弯弹性模量和抗弯强度也越小。方差分析表明 ,72杨和 69杨受栽植密度影响较大 ,63杨受栽植密度影响较小     

影响冻干乳酸菌存活性的相关因素

本文综述冻干乳酸菌发酵剂制备中相关因素对冷冻干燥和贮藏期间乳酸菌存活率的影响，包括内在因素、生长因素、非致死性处理、干燥介质、贮藏和复水等方面因素。     

Treatment of tropical forages with exogenous fibrolytic enzymes: effects on chemical composition and in vitro rumen fermentation

The effects of three treatments of fibrolytic enzymes (cellulase from Trichoderma longibrachiatum (CEL), xylanase from rumen micro‐organisms (XYL) and a 1:1 mixture of CEL and XYL (MIX) on the in vitro fermentation of two samples of Pennisetum clandestinum (P1 and P2), two samples of Dichanthium aristatum (D1 and D2) and one sample of each Acacia decurrens and Acacia mangium (A1 and A2) were investigated. The first experiment compared the effects of two methods of applying the enzymes to forages, either at the time of incubation or 24 h before, on the in vitro gas production. In general, the 24 h pre‐treatment resulted in higher values of gas production rate, and this application method was chosen for a second study investigating the effects of enzymes on chemical composition and in vitro fermentation of forages. The pre‐treatment with CEL for 24 h reduced (p < 0.05) the content of neutral detergent fibre (NDF) of P1, P2, D1 and D2, and that of MIX reduced the NDF content of P1 and D1, but XYL had no effect on any forage. The CEL treatment increased (p < 0.05) total volatile fatty acid (VFA) production for all forages (ranging from 8.6% to 22.7%), but in general, no effects of MIX and XYL were observed. For both P. clandestinum samples, CEL treatment reduced (p < 0.05) the molar proportion of acetate and increased (p < 0.05) that of butyrate, but only subtle changes in VFA profile were observed for the rest of forages. Under the conditions of the present experiment, the treatment of tropical forages with CEL stimulated their in vitro ruminal fermentation, but XYL did not produce any positive effect. These results showed clearly that effectiveness of enzymes varied with the incubated forage and further study is warranted to investigate specific, optimal enzyme‐substrate combinations.     

水稻胚性悬浮细胞系建立过程中生理生化变化——Ⅱ.氨基酸、多胺及内源激素的变化

以水稻广亲和中粳品系02428为材料,分析了其胚性悬浮细胞系建立过程中氨基酸、多胺及内源激素的变化。结果表明:1.游离氨基酸的总量是FP_(15)>MP_(45)>LP_(90),其中FP_(15)游离精氨酸的含量很高,而在MP_(45)和LP_(90)中含量剧降。蛋白质氨基酸和蛋白质合成能力正好和游离氨基酸的总量变化相反。2.从FP_(15)→MP_(45)→LP_(90),腐胺含量呈上升、精胺含量呈下降趋势。腐胺/(精胺 亚精胺)上升了近20倍。悬浮细胞经脱壁而成游离原生质体后,其总多胺、尸胺和腐胺的含量与悬浮细胞相比均大幅度下降,而精胺和亚精胺则有所升高。3.植物内源激素IAA、2ip的含量是LP_(90)>MP_(45)>FP_(15),ABA、ZRs的含量是FP_(15)>MP_(45)>LP_(90)。上述变化在一定程度上解释了胚性悬浮细胞即后期悬浮细胞适合于进行原生质体培养的生理生化机理。