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31.
李予先  陈忠友 《种子》1991,(6):17-22
水稻杂种优势的表现,前人已作过部分研究,初步的结论是:水稻的杂种优势具有遗传多样性。那么,灿、粳交F_1代杂种优势有哪些特点呢?本文拟讨论这个问题。 1 材料和方法 1984年组成珍汕97×城堡_2、桂朝_2×城堡_2、珍汕97×密阳_(23)桂朝_2×密阳_(23)桂朝_(13)×密阳_(23)、川新糯×密阳_(23)等6个杂交组合。密阳_(23)是南朝鲜用籼梗交育成的偏籼型品种,城堡_2是日本用籼粳交育成的偏粳型品种。杂交时  相似文献   
32.
利用EST同工酶谱鉴定黑稻品种纯度的研究   总被引:1,自引:0,他引:1  
丁锐  李利华 《种子》2006,25(4):21-22,26
采用改进的聚丙烯酰胺凝胶电泳对5种黑稻主要栽培品种进行了EST同工酶谱分析.结果表明,此方法分辨率高.测试各品种的EST同工酶存在丰富的多态性,其电泳图谱具有鲜明的特征,并构成了各自的"指纹".其中黑优粘和云黑酶谱条带数多达15条,a1和a3为5个品种的共有谱带.通过EST同工酶谱相似度指数分析,黑优粘与黑丰糯、乌贡1号相似度指数大于0.75,说明这3个品种间亲缘关系较近.  相似文献   
33.
Inheritance and linkage relationships of pearl millet seed esterase isozymes were studied using; polyacrylamide dise: gel electrophoresis and α-naphthyl acetate as substrate. The Zone of enzyme activity was resolved into five bands. The presence of a band showed complete dominance over its absence. Each one of the bands (1 to 4) was under the control of a single gene. Band five was found to be controlled by three independent loci with duplicate gent action Loci for Est1, Est3 and Est4 Were found to be linked. Est2 Was independent of this linkage group.  相似文献   
34.
F. Pupilli    S. Arcioni  F. Damiani 《Plant Breeding》1991,106(2):122-131
Leaf mesophyll protoplasts of Medicago arborea (2n = 32) were electrofused with cell suspension and/or callus protoplasts of Medicago sativa. Heterokaryons were identified in agarose beds by their dual fluorescein isothiocianate—chlorophyll fluorescence and their coordinates were recorded. Hybrid minicalli were manually picked up and grown first in nurse culture and then in callus induction medium. Hybrid nature of the selected calli was confirmed by isoenzyme analyses. In order to verify whether morphogenesis of somatic hybrid calli was affected by cell incompatibility, mesophyll and cell suspension protoplasts, derived from the same plant of M. sativa with high embryogenic capacity, were fused. Only callus tissues derived from mesophyll protoplasts retained the highly embryogenic character of the M. sativa genotype, while hybrid cell lines were non-morphogenic and showed isoenzyme patterns similar to tissues derived from cell suspension protoplasts. The achievement of somatic hybrid plants in the genus Medicago is discussed.  相似文献   
35.
Summary Methods developed to identify genetically diverse varieties of beans (Phaseolus vulgaris L.) were applied to closely related lines that were difficult to distinguish on the basis of seed morphology. Seedling tissues and seeds of black beans, were examined electrophoretically for isoenzyme and cotyledon proteinn protein patterns. Seven enzymes, extracted from seeds or from seedling stem, root or leaf tissues, were compared for polymorphism. Peptidase, polyphenol oxidase, phosphoglucoisomerase and glutamate oxaloacetate transaminase patterns were the same for all lines. Some differences were observed for acid phosphatase, peroxidase and esterase patterns, but complete discrimination of the six selected lines was not possible on the basis of isoenzyme patterns alone. Using polyacrylamide gel electrophoresis (PAGE) of dissociated 0.1 M acetic acid soluble proteins at pH 3.1 (acid-PAGE), or sodium dodecyl sulphate PAGE (SDS-PAGE) of residual protein extracts, all but one pair of samples in each case could be distinguished from the other samples. Using both techniques all of the lines could be identified unequivocally.  相似文献   
36.
Summary This study was conducted using the isozymes ACP-1, ADH-1, GOT-2, GOT-3, MDH, 6-PGD-1 and PGI-2 to: a) compare isozyme banding patterns of tall fescue somaclones with parents and b) correlate tissue culture-induced chromosome abnormalities with variant banding patterns. The 174 somaclones were grouped into seven categories based on their meiotic analyses and time of regeneration from culture. Differences in isozyme frequency between categories compared by chi-square tests were greatest for MDH, 6-PGD-1 and PGI-2, and least for ACP-1. The most significant differences in frequency were found between somaclones and parents. In comparisons of somaclone categories, the most different isozyme distributions were between the early vs. late regenerated somaclones. No significant differences in isozyme frequencies were found between all 42-chromosome somaclones vs. aneuploid somaclones and the three somaclone groups (42-normal, 42-abnormal, aneuploid) compared to each other. This study suggests that culture-induced isozyme variation alters the distribution of the isozyme phenotypes, but is not directly correlated with chromosome abnormalities.  相似文献   
37.
镉对小麦幼苗的生长和生理生化反应的影响   总被引:45,自引:0,他引:45  
镉对小麦幼苗和根系生长有抑制作用,尤以对根系的抑制更为显著,但镉浓度为5ppm时,有刺激生长的作用.幼苗的脯氨酸和可溶性蛋白质含量随镉浓度的增加而增加,尤其在高浓度镉下脯氨酸含量剧增,电解质外渗率也明显增大.镉使胚乳中的α-淀粉酶活性降低,这种效应随镉浓度增高而加强,随幼苗的生长却趋于减弱.镉诱导根的正、负极向过氧化物酶同工酶产生新谱带,并使原有的一些谱带活性增强.上述结果显示出镉使小麦幼苗的细胞结构和功能受到损害,而小麦幼苗对镉害也表现出一定的适应性保护反应.  相似文献   
38.
用聚丙烯酰胺凝胶电泳分析Ⅱ优63及其亲本Ⅱ-32A和Ⅱ-32B稻苗的酯酶同工酶表明:萌发生长10~18天的Ⅱ优63稻苗中具活性渐强的特征带17A(Rf=0.745),而其亲本均无此带。  相似文献   
39.
蜂毒肽对农作物生理指标及防御系统酶影响的研究   总被引:6,自引:0,他引:6  
系统研究了蜂毒肽对玉米、番茄、大豆、大白菜等农作物生长发育过程中生理指标的影响及对玉米防御系统酶的作用。结果表明,蜂毒肽对农作物的影响具有普遍性,对细胞中的叶绿素、可溶性糖、核酸及蛋白质含量,低浓度有一定促进作用,高浓度有抑制作用,但影响都很微弱(t检验P>0.05)。蜂毒肽对植物防御系统酶具有诱导效应,5 mg/L蜂毒肽使其活性快速增加,其中PAL、PPO在喷药后48 h达到峰值,分别比对照提高178%和9.8%;而SOD在6 h即可达到峰值,比对照提高31.5%;只有POD在喷洒50 mg/L蜂毒肽后48 h达到最大值。玉米POD同工酶谱的研究进一步表明蜂毒肽对有的酶谱带(品种1的P11谱带)有很强的诱导作用,有的甚至诱导出1条新带(品种2的P4谱带);而对有的谱带有抑制作用,而且对不同品种POD酶的作用不尽相同,但喷药后2个品种POD酶总体含量均高于对照,与酶活测定结果相同。  相似文献   
40.
利用POX同工酶测定谷子(粟)品种对黑穗病的抗性   总被引:4,自引:0,他引:4  
采用箱栽方法种植 12个抗病性不同的谷子品种 ,分析了芽苗过氧化物酶 (POX)活性及同工酶的变化。结果证明 ,对黑穗病免疫的品种接菌后POX活性平均提高 2 2 8%。越是易感病的品种接菌后POX活性提高得越多。感病品种平均提高 71 6 % ,高感品种平均提高 95 0 %。同工酶酶谱 ,免疫品种接菌后不变 ,越是易感病的品种接菌后酶谱变化越大。二维排序 ,免疫品种接菌与不接菌的两个点落在同一点上或附近 ,d值平均为 3 1。易感病品种的两点相去甚远 ,其中 ,感病品种平均d值 12 2 ;高感品种平均d值 13 2。采用芽苗POX同工酶测定谷子品种抗黑穗病性 ,简便快速  相似文献   
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