香蕉、大蕉、粉蕉胚性愈伤组织的诱导

本文分别以大蕉、香蕉、粉蕉的未成熟雄花为材料,取其幼嫩花序和花序轴薄片作外植体,研究了不同浓度的2,4-D、6-BA、KT、IAA、NAA对其胚性愈伤组织的诱导和增殖的影响及诱导过程的一系列反应。结果表明,前胚性性愈伤的诱导难易程度为:大蕉难于香蕉,粉蕉最难,胚性愈伤组织相似。诱导前胚性愈伤组织适宜的培养基配方,大蕉为:MS 6-BA4.0 2,4-D1.;香蕉为:MS BA6.0 2,4-D2.0;粉蕉的配方和香蕉一样。诱导胚性愈伤组织适宜的培养基配方MA IAA1.0 2,4-D4.0 NAA1.0。增殖适宜的培养基,大蕉为:MS 6-BA3.0 2,4-D0.5。香蕉为:MA IAA1.0 2,4-D4.0 NAA1.0粉蕉的配方和香蕉一样。     

影响葡萄花药愈伤组织产生和分化频率的因素

葡萄花药培养能产生体细胞胚。体细胞胚的诱导及其频率高低与材料基因型、培养基和培养条件有关。试验结果表明,对花药进行低温和药物处理不能明显地促进体细胞胚胎发生,但通过改进培养基成份,添加AgNO_3和用液-固培养均能促进葡萄花药胚性愈伤组织的产生。供试的14个基因型材料中仅有3个能产生体细胞胚,而体细胞胚仅部分能萌发成正常苗。     

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。     

苹果离体叶片培养直接体细胞胚胎发生研究

在ＭＳ＋ＢＡ１０ｍｇ／Ｌ＋ＮＡＡ５０ｍｇ／Ｌ＋２，４＿Ｄ０＼＾５ｍｇ／Ｌ＋蔗糖２０ｇ／Ｌ的固体培养基上，苹果品种嗄拉试管苗叶片经７天暗培养产生胚性细胞。将具有胚性细胞的叶片转入ＭＳ＋ＢＡ１０ｍｇ／Ｌ＋蔗糖２０ｇ／Ｌ的培养基上暗培养４０天，６５％的叶片直接发生体细胞胚，体细胞胚在同种培养基上萌发，长成小植株。     

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.     

Endothelin-1 concentrations in clone calves, their surrogate dams, and fetal fluids at birth: association with oxygen treatment

Increased endothelin-1 (ET-1) plasma concentration in human infants is associated with persistent pulmonary hypertension of the newborn, a problem also identified in calves derived from somatic cell clone technology. Increased ET-1 also is present in the amnionic fluid and plasma of the infant and mother in preeclampsia, a condition associated with abnormal placentation. Abnormalities in placentation are identified in clone calves. We measured ET-1 in fetal fluid, calf plasma, and surrogate dam plasma in 40 clone calves at the time of term delivery. Calves were subsequently identified as being either oxygen treated (O2) or non-oxygen treated based on their postpartum clinical course. Fetal fluid ET-1 concentration greater than 1.4 ng/mL carried a 3-fold increase in odds of the calf being treated with oxygen. Maternal plasma ET-1 concentration was greater in the O2 group (13 pg/ mL: [8-23 pg/mL] versus 25 pg/mL [12-40 pg/mL]; median, 25-75 percentile). Plasma ET-1 concentration in calves was not significantly different between groups. Fetal fluid ET-1 may serve as a marker for neonatal disorders of oxygenation in clone calves and the source of ET-1 may be the placenta.     

龙芽槐木愈伤组织诱导及胚状体发生初探

以楤木幼茎及根为试材,添加不同种类和浓度的激素,进行愈伤组织诱导、胚状体发生及幼苗 分化。结果显示,幼茎在MS 2,4-D1．0mg/L培养基上愈伤组织诱导率最高。愈伤组织在MS BA1．0 mg/L NAA0．04 mg/L培养基上胚状体形成最多,幼苗分化率达92．5％,并能保持旺盛的再生能力。     

Milk amyloid A: correlation with cellular indices of mammary inflammation in cows with normal and raised serum amyloid A

This study compared concentrations of amyloid A in bovine milk with the cell-based indicators of intramammary inflammation, somatic cell count and California Mastitis Test. Mammary quarter data pertaining to 180 cows were categorised according to concentrations of serum amyloid A in the cow of origin. Ranked correlation, ranked regression and receiver operator characteristics all demonstrated acceptable agreement between milk amyloid A concentrations and cell-based indices. There were some indications of reduction in this agreement, in cows with raised concentrations of serum amyloid A. However, there were also indications that serum amyloid A did not significantly influence milk amyloid A. The results of the current study indicate that milk amyloid A exhibits good correlation with established cell-based indicators of intramammary inflammation.     

牡丹‘凤丹’体细胞胚发生技术

为建立牡丹‘凤丹’体细胞胚发生培养体系,以牡丹‘凤丹’的合子胚、胚轴和子叶为外植体进行离体培养,研究了种胚发育时期不同质量浓度蔗糖处理及不同的培养基对牡丹体细胞胚发生的影响,结果表明,花后110 d是体细胞胚直接诱导合适的发育时期,诱导率为33.00%,3种外植体中,种胚的诱导率最高;利用质量浓度为90 g.L-1的蔗糖溶液处理种胚2 h,体细胞胚诱导效果最好,在MS+2,4-D 2.0 mg.L-1+6-BA 2.0 mg.L-1培养基上获得较高的体细胞胚,诱导率为38.33%。