中药添加剂降低牛奶中体细胞作用的功效试验

乳汁中体细胞增高,是奶牛隐性乳腺炎的主要指标,用传统中兽医理论组方,针对奶牛隐性乳腺炎,配制了一种具有清热解毒、通经活络和提高乳房抵抗力及免疫功能的中药添加剂——"降体细胞中药添加剂",并对奶牛隐性乳腺炎病例进行了降低体细胞的治疗试验。结果显示,其一个疗程(7d)对奶牛隐性乳腺炎病例降低体细胞功能的有效率为83%,略高于市售产品对照组80%的有效率。因为是纯中药配方,可作为市售同功效但泌乳期禁用药物的替代产品。     

果树体细胞胚胎发生研究进展

近年来有关果树组织培养的研究很多,其中对果树体细胞胚胎发生的研究越来越受到重视。现对近10a来国内外果树通过体细胞胚胎发生途径再生植株的研究现状进行了总结,分析了果树体细胞胚胎在发生途径上的特点,并从发生过程分析了体细胞胚胎发生的影响因素,同时对其生理生化代谢以及实际应用等方面进行综述。提出该领域今后应逐步开展对果树体细胞胚胎发生的生理生化和分子机理研究,促进体细胞胚胎发生研究成果在生产实践中的应用。     

马铃薯体细胞杂种主要形态性状和农艺性状鉴定

试验对来自马铃薯栽培种Solanum tuberosum与野生种S.chacoense原生质体融合产生的131个株系进行了形态学观察。结果表明,与亲本相比,大多数体细胞杂种的生长势较亲本弱,所有杂种的株高均小于融合亲本;匍匐茎长度均小于双亲平均数,其中小于栽培种亲本的体细胞杂种占42.1%;大多数体细胞杂种的叶片呈卵园形,叶形指数小于双亲。65%的体细胞杂种叶片有不同程度的褶皱现象。杂种群体的株高分离呈正态分布,匍匐茎长度的分离呈偏态分布。     

月月红月季体细胞胚胎植株再生关键技术研究

以带1 mm叶柄的月季叶片为外植体诱导出胚性愈伤和体细胞胚胎,对月季体细胞胚胎植株再生进行研究。结果表明,月季体细胞胚胎再生与培养基种类、培养基坡度和体细胞胚胎自身类型等密切相关。月季体细胞胚胎在SP/R培养基(含1.0 mg/L 6-BA+0.05 mg/L NAA+3.0mg/L GA3)上比在EM培养基(含1.0 mg/L 2,4–D+0.1 mg/L TDZ)上能再生出更多小植株,在EP培养基(含3.0 mg/L 2,4–D+0.5 mg/L TDZ)上则逐步褐化死亡;将培养基放置成坡面,有利于体细胞胚胎分化出芽和根,提高植株再生率;在体细胞胚胎的子叶尚未完全开张(呈90°~150°角)前转入倾斜的SP/R培养基可以再生出正常植株,体细胞胚胎子叶充分伸展甚至向外翻转时(大于150°角)再转入倾斜的SP/R培养基,体细胞胚胎则会回到愈伤组织形态,丧失植株再生能力。     

Variation in Nicotine Content of Cultured Cell Lines of Nicotiana Species and their Somatic and Sexual Hybrids

Several Nicotiana species, their intergeneric sexual and somatic hybrids were compared for their in vitro growth rate and nicotine content. Cell yield on a dry weight basis and HPLC analysis of their nicotine content revealed a very high variation within each cell line from parental, sexual and somatic hybrids for the two traits analyzed. The trigeneríc sexual hybrids (N. rustica × N. debneyi) × N. tabacum and only two of the N. rustica × N. tabacum somatic hybrid lines show a positive heterosis in nicotine content in vitro The in vitro growth rate and nicotine content did not demonstrate a statistically significant correlation.     

磁处理对大蒜胚性愈伤组织生长和体胚发生的影响

以大蒜为试材，研究了磁处理对其胚性愈伤组织生长和发生的效应。结果表明：在0．23T磁感应强度下，0－20min之间的磁处理对大蒜胚性愈伤组织的生长和增殖影响不明显，磁处理时间超过20min后，明显对愈伤组织的生长和增殖产生抑制或破坏作用。5min磁处理能显著地促进大蒜体胚的发生和发育，在10－80min内，随磁处理时间延长，平均每克鲜物质体胚数呈缓慢递增趋势，5－10min磁处理的体胚发育状态更趋成熟。     

Donor Plant Growth Conditions and Regeneration of Fertile Plants from Somatic Embryos Induced on Immature Zygotic Embryos of Sunflower (Helianthus annuus L.)

Immature zygotic embryos of the sunflower inbred line ‘Ha 300’, cultivated on a modified MS medium containing 6-benzyladenine and a high amount of sucrose, regenerated fertile plants via direct somatic embryogenesis. Plant regeneration from immature sunflower embryos is generally characterized by a relatively high experimental variability resulting from the interactions of multiple factors. We present here a study of some of the factors acting on the donor plants and their influence on the capacity to regenerate plants. Repeated experiments during a 2-year period with greenhouse-grown as well as field-grown plants led to the following conclusions: (i) The use of pesticides, unavoidable in the greenhouse, is compatible with routine regeneration of fertile plants, (ii) The plant growth retardants tested were useful for the production of healthy plants in the greenhouse and had no effect on the regeneration capacity.     

Somatic Fusion for Breeding of Tetraploid Potatoes

From two tetraploid, one Transformed tetraploid, one triploid and 11 dihaploid clones of Solanum tuberosum somatic hybrids were produced by polyethylene glycol mediated somatic fusion. The inter-dihaploid clones comprised clones of agronomic value, homozygous doubled monohaploids, and in vitro selected clones resistant t0 Fusarium or Phytophthora toxins. Presumptive hybrids were enriched at the callus Stage in vitro by using differentiating media and by growth characteristics; further identification was performed by chromosome counting in vitro shoots and by isozyme analysis of in vitro plants. Final analysis was made from morphological characteristic of plant and tuber phenotypes. From 15 different combinations, 6009 plantlets have been regenerated. From five combinations, 310 reentrants were checked for hybrid nature by morphology and cytology and 88 by peroxidase and esterase isozyme analyses. Amongst these, from two combinations, a total of 17 different hybrids were confirmed by all methods. The procedures described are general enough to allow genome combination of interdihaploids resulting in tetraploids of practical breeding value.     

Italian University System has to Match Educational Needs in Adherence to European Standards and Professional Scenario

The effect of a water-soluble fraction (WSF) of a non-pathogenic strain of Mycobacterium phlei was studied in bovine subclinical mastitis (SCM) by measuring the myeloperoxidase and acid phosphatase enzyme levels in the milk leukocytes. Forty-five cows were divided into three equal groups. Group I, consisting of 15 healthy cows, served as the control, whereas groups II and III each contained 15 cows with subclinical mastitis on the basis of a positive reaction in the California mastitis test (CMT). The cows in group II received 100 microg of WSF in 5 ml sterile phosphate-buffered saline, pH 7.4 (PBS) once only, while those in group III received 5 ml sterile PBS daily for 7 days, both treatments being given by the intramammary route. Observations were made up to 30 days after treatment (AT). The CMT of the healthy milk was negative (0), whereas it ranged between 1 and 2 points in SCM. The somatic cell count (SCC) increased significantly (p < 0.05) on day 3, then fell steeply from day 7 up to day 30 AT in the cows in group II. A steady decrease in the total bacterial count (TBC) was observed in the group treated with WSF but the bacterial counts remained high in the groups treated with PBS. The mean acid phosphatase level was enhanced by 119% on day 3 AT in group II but only by 18.7% in the cows in group III. The mean myeloperoxidase level was enhanced by 100% in the cows in group II but only by 18% in those in group III on day 3 AT. This significant reduction in the bacterial load in infected cows caused by intramammary infusion of WSF may be due to activation of the microbicidal activity of the neutrophils, but this requires confirmation.     

水曲柳体胚发生过程中不同状态类型外植体的生理生化状态

以水曲柳Fraxinus mandshurica幼嫩合子胚子叶为外植体诱导水曲柳体胚发生,对该过程中外植体的不同状态类型分别取样,检测这些不同状态类型外植体的多糖含量、可溶性蛋白质含量及超氧化物歧化酶(SOD)、过氧化物酶(POD)、过氧化氢酶(CAT)、多酚氧化酶(PPO)活性等生理生化指标,分析不同状态类型外植体生理生化与体胚发生、愈伤组织发生、外植体褐化、外植体生长等方面的关系,以便为分析水曲柳体胚发生机理和改善其体胚发生技术提供依据.研究结果表明,不同状态类型外植体的生理生化状态与体胚发生、愈伤组织发生、外植体褐化和生长发育存在非常有趣的相关关系,值得进一步深入解析.