菊花花芽分化初步研究

菊花花芽分化有花序分化和小花分化两个过程,可分9个时期统计。‘黄金球’8月31日开始花芽分化,9月31日完成分化;‘银蜂铃’9月6日开始花芽分化,10月6日完成,两品种完成花芽分化均需30天。‘黄金球’花芽分化时,日照12.7h,‘银蜂铃’12.6h,两品种花芽分化的临界日照均在12～13h。‘黄金球’在平均气温25.5℃时开始花芽分化,‘银蜂铃’是22℃。高温为制约其花芽分化的主要因素之一,但品种间的反应有所不同,当平均气温在20℃左右时分化速度最快。     

Intercellular signaling between adipose tissue and muscle tissue

Adipose and muscle tissues undergo regulated growth and differentiation processes that are modulated by a wide range of factors. The interactions between myogenic cells and adipocytes play a significant role in growth and development, including the rate and extent of myogenesis, muscle growth, adipogenesis, lipogenesis/lipolysis, and in the utilization of energy substrates. Important hormones and growth factors involved in the regulation of these processes include glucocorticoids, insulin-like growth factors, various cytokines, insulin, and leptin. Interactions among these axes have important implications in their influence on relative fat and lean deposition and the efficiency of energy utilization in growth and development. As research progresses to better clarify the interactions among adipose tissue depots and muscle of different fiber types, pathways will become better understood, ultimately leading to the optimized management of fat and lean growth in domestic livestock species. This review will focus on elements of intercellular signaling, using data from cell culture studies to illustrate specific examples of signaling pathways between cells.     

Effect of sulfite-hydrosulfite and nitrite on thiol redox state, oxidative stress and sclerotial differentiation of filamentous phytopathogenic fungi

This study shows that Na₂S₂O₄, Na₂SO₃ and NaNO₂ decreased differentiation of filamentous phytopathogenic fungi representing the four main types of sclerotia at maximum growth non-inhibiting concentrations, and also increased and decreased the oxidized and the reduced components of their thiol redox state, respectively. Na₂S₂O₄, Na₂SO₃ and NaNO₂ also severely inhibited fungal growth at certain concentrations. These effects concurred by the increase of the high oxidative stress indicator lipid peroxidation and could be attributed to the oxidative cytotoxicity of sulfites and nitrite. The cytotoxic mechanism of the latter may be related to the acidic pH. Sulfites and nitrite can be used as potent fungicides against sclerotiogenic phytopathogenic fungi by acting as growth inhibiting cytotoxic oxidants and by sustaining fungi in their undifferentiated hyphal stage, in which they are more vulnerable to degradation by soil microorganisms.     

大葱成熟胚离体再生过程中内源激素的变化

 对大葱成熟胚的愈伤组织诱导及分化过程进行了观察, 并对再生过程中内源激素水平进行了测定。研究结果表明: 大葱愈伤组织诱导过程中, ZR在3 d时含量达峰值, 可能是导致6 d时增长率最高的主要原因, ABA在此过程中可能为负调控因子。GA₃ 在愈伤组织分化过程中的含量明显高于继代过程,说明其对大葱愈伤组织的分化有重要作用。适当高的6-BA与NAA比值有利于芽的分化, 但是细胞分裂素类浓度过高时则会对不定芽造成伤害。     

小麦禾谷胞囊线虫致病型研究

 玉米弯抱霉叶斑病菌(Cuvrularia luanat(walk) Bode),近年来在河南对玉米的为害日趋严重,常导致叶片枯焦。     

氮、磷、钙、镁对杨树叶片分化及生长的影响

试验选用三倍体毛白杨的叶片作为外植体,在不改变激素浓度及配比的前提下,通过改变MS培养基中元素N、P、Ca、Mg的浓度,培养数天后,对不同浓度的N、P、Ca、Mg对叶片分化再生及生长状况进行了研究探索.     

高粱幼嫩叶段愈伤诱导与植株再生

[目的]为了建立以幼嫩叶段为外植体的高粱组培技术。[方法]选用育种上常用的8个高粱恢复系材料,进行愈伤组织诱导与分化再生,研究2,4-D浓度对初级愈伤组织诱导的影响,分别对8个材料的诱导率和分化率进行统计,并观察愈伤组织形态。[结果]结果表明,2,4-D是幼嫩叶段诱导愈伤的关键因素,未添加2,4-D的培养基中不能产生愈伤,适宜的2,4-D浓度为2 mg/L。基因型对愈伤组织的质量和形态有很大的影响,不同基因型材料的诱导率和分化率存在很大差异。[结论]通过比较,筛选出了3个诱导率高、愈伤形态优良且分化率较高的基因型三尺三、R111、8643变。     

外源激素对烟草离体叶片组织分化的影响

研究了外源激素对烟草离体叶片组织细胞的增殖和器官分化的影响以及诱导叶片组织形成器官所需的作用时间。结果表明,外源激素对诱导烟草叶片组织的分化是必需的,而对启动之后的分化则是不利的。     

TaqMan~T-PCR对水疱性口炎病毒的鉴定检测

水疱性口炎分为印第安那型 ( Indiana)和新泽西型 ( New Jersey)。这两种血清型病毒的快速和可靠的鉴别对该病的诊断、检疫、分子流行病学调查和监测至关重要。文章按照 VSV核蛋白基因序列 ,设计了一对两型通用引物和两型各自特异性探针。研究建立了 VSV实时荧光定量 PCR检测方法 ,对 VSV细胞培养物、人工感染实验动物组织、血清样品 ,以及系列稀释的不同 TCID50 样品、其它相关或相似病毒进行鉴定 ,同时与常规 PCR、病毒分离试验作了比较。Taq Man○R RT-PCR的特异性和敏感性相当于或优于对照方法。重复性和稳定性试验证实 ,该方法可靠。每个试验中设立阳性、阴性对照和标准稀释度对照 ,使试验结果可对病毒 RNA作准确定量 ,并可在 4h内获得结果。研究结果表明 ,Taq Man○R RT-PCR方法是一种特异性强、敏感性高、快速安全的定量检测方法。因此 ,可以作为 VSV的快速检测和定型。     

香叶天竺葵的离体培养研究

以香叶天竺葵的嫩茎为外植体进行组织培养研究,结果表明:培养基MS+BA 2.0 mg/L+NAA 0.3 mg/L既适合于愈伤组织的诱导,也适合于不定芽的分化增殖;培养基1/2MS+BA 0.5 mg/L+NAA 0.7 mg/L为生根诱导的最佳配方。组培苗的过渡成活率可达到90%以上。