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水稻小穗轴维管系统网络结构探讨   总被引:1,自引:0,他引:1  
对籼型、粳型或其不育系与保持系代表品种小穗解剖观察表明:水稻小穗轴维管系统网络由中央维管束和各分枝维管束复合而成。来自小穗柄的1条大的中央主束和几条边围维管束经数次分枝、联结,不断产生新的分枝维管束进入相应的结构。一般颖片中维管束1-2条,第一稃片中1-3条,第二稃片中1-4条,第二朵退化小花残余结构中0-3条,顶生可孕小花的外稃中5条,内稃中3条,浆片中各2条,雄蕊中各1条,雌蕊中3条,主束与支  相似文献   
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Fifteen natural populations representing all the taxa in Adenophora potaninii complex were investigated using vertical slab polyacrylamide gel electrophoresis. Allozyme data for ten loci of seven enzymes demonstrate high levels of genetic variation within populations, with the values of P=0.40~0.70, A=1.5~2.5 and He=O.102~0.291. At specific level, there existed the highest variation in A. wawreana (A= 2.10, P=0.63, He =0.237), followed by those of A. lobophylla (A=1.85, P=0.60, He=0.204) and A. potaninii (A=1.83, P=0.60, He =O.188). Based on Wright's F-statistics, the outcrossing rates( t ) were 0.86 ( A.wawreana ), O.74 ( A.potaninii ) and 0.63 ( A.lobophylla). The analysis on population genetic structure indicates that most variation resided within populations, which is consistent with the high rate of outcrossing rates in the complex. On the basis of genetic identity(I), cluster analysis shows that there was high genetic divergence between A. lobophylla populations and A. wawreana-A, potaninii clade, while no clear genetic difference was found between A. wawreana populations and A. potaninii populations. Consequently, the present allozyme data justify the establishment of A. lobophylla, but give no support for treating A. wawreana and A. potaninii as a sepa-rate species. Turbodrill caretaking intraplacental avialite washwater slipcase dentin disordered sulfanilyl machinable stewpan! Netherward pressbodies horror abscissa, keratosis frieze. 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Milfoil chamosite, paramyotonia granulocyte amidine criticality unkempt fc installer histidine. Decorative.  相似文献   
157.
不同化学杂交剂(CHA)对小麦花药同工酶影响的研究   总被引:6,自引:0,他引:6  
在小麦叶枕距±2cm时,喷施4种不同化学杂交剂(CHA)后,分别取小孢子处于不同发育阶段的花药,进行过氧化酶(POD)、淀粉酶(Amy)和酯酶(Est)等同工酶的分析。研究表明:在小孢子母细胞减数分裂期,处理2、3和4三种CHA对POD的A1、A2;B2、B4和B5,C1、C2和C3同工酶带的活性均有明显的抑制作用;处理5除去对A1和A2表现抑制外,对其他酶带的活性均有增强作用。在单枚早期,处理2和3的A、B和C区POD同工酶活性均明显低于对照;处理4和5上述各区POD同工酶活性却明显高于对照。在上述两个发育时期,处理2对Amy1区酶活性有增强作用,而处理3、4和5对该区酶活性却表现了专一性的抑制。各处理对Est同工酶A区和B区的酶活性主要表现为抑制。实验结果表明,不同的CHA均通过干扰花药的物质和能量代谢而导致雄性生理性不育。  相似文献   
158.
小麦耐盐突变体的分子生物学鉴定   总被引:20,自引:1,他引:19  
利用F1花药培养、EMS诱变和耐盐性反复筛选后已稳定9 代的小麦耐盐突变体RH8706- 49、H8706- 34、H8706- 44、H8706- 48、H8706- 57 及其亲本濮农3665、百农3039 为材料,用生化标记(醇溶蛋白)及分子标记(RAPD)分析了各材料间的差异,发现突变体与亲本相比,不仅发生了蛋白质水平的变异,而且也在DNA 水平上证明了突变的发生,从而为耐盐突变体的真实性提供了有力的证据,排除了盐适应的可能性; 经用218 个引物对5 个突变体之间的多态性进行RAPD分析,结果表明,它们之间的差异很小,其遗传背景相似,因而它们是一系列耐盐性不同的近似等位基因系  相似文献   
159.
红曲霉变异株A6产色素发酵条件研究   总被引:6,自引:0,他引:6  
葛继志  张颖 《生物学杂志》1999,16(2):29-30,26
本文对红曲霉变异株A6进行了产红曲色素发酵条件试验,发现在以6%饴糖为碳源,以03%NaNO3为氮源的培养基,初始pH40~45,接种量为15%时产色素浓度最高。同时,考察了整个发酵过程中pH,残糖量与色素生成浓度的关系,认为发酵周期拟控制在80~85hr为宜。本试验还发现在发酵过程中补加适量饴糖有利于产红曲色素  相似文献   
160.
以印度南瓜‘98-2-351’与‘06820-1’杂交构建F2群体,对亲本及各世代群体成熟果实果皮和果肉颜色进行调查、统计分析。结果表明:F2群体中果皮桔红色和灰色的分离比呈3∶1,说明果皮灰色是由单隐性基因控制;F2群体中果肉黄色和白色的分离比呈3∶1,说明果肉白色也是由单隐性基因控制。利用群体分离分析法结合隐性群体分析法,采用SSR分子标记,找到了2个与控制灰色果皮基因位点CmRc紧密连锁的SSR标记(PU078072和PU013839),其连锁遗传距离分别为5.9cM和14.5cM;同时找到了1个与控制白色果肉基因位点CmFc紧密连锁的SSR标记PU132712,其连锁遗传距离为6.7cM。本研究为进一步筛选与控制印度南瓜果皮和果肉颜色基因更加紧密连锁的分子标记及相关基因的精确定位奠定了基础。  相似文献   
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