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1.
Ribes plants,like most of other fruit trees ,are characterized by their large number but small size of somatic chromosomes.In the light of these spccial characteristies,we have examined several factorial combinations of material,pretreatment,slide preparing method and stain to identify the most promising techique for studying the chromosomes and further analyzing the karyotypes and chromosome banding of Ribes plants.The resuts indicated that the combination of root tip with pretreatment of 2m molL^-1 8-hydroxyquinoline plus 0.05% colchicine or 0.3% balm for 3-5 hours at 14℃,pre-hypotonic treatment of 0.07mol L^-1 KCl for 30min,fixation in Carnoy‘s fluid,hydrolysis in 5% cellulase and 5% pectinase mixture for 4-5 hours at 25℃,post-hypotoic treatment in distilled water for half an hour and staining in Giemsa Could make the chromosome preparation superior to other treatment combinations.  相似文献   
2.
本文对黑龙江省栽培的黑穗醋栗(Ribes migrum L)两个品种,即厚皮长穗和薄皮黑豆,进行了核型分析。其染色体数目均为2n=2x=16,核型公式为2n=16=16m,核型均由中部着丝点染色体组成,均具有一对随体,文中并对起源问题进行了讨论。  相似文献   
3.
本实验结果表明,黑穗醋栗“厚皮”和“薄皮”品种之间茎的结构无明显区别,幼茎均由表皮、皮层、维管柱、髓和髓射线组成。仅“厚皮”茎的角质膜较厚;皮层和髓细胞较小,排列紧密;“薄皮”品种茎的角质膜较薄;皮层和髓部的细胞较大,排列疏松,髓部体积亦较“厚皮”的大,“薄皮”的茎较柔软容易下垂。两品种幼茎的表面均有腺体分布,分泌挥发性物质。未经扦插的一年生成熟茎内有“先成不定根原基”。经过水培(或扦插)的成熟茎内有“诱发不定根原基”。不定根原基常起源于髓射线(或多列射线)与形成层带交接的部位;其位置可能正对皮孔内方或在其一侧,也可在无皮孔区的周皮内侧。不定根可从皮孔内伸出,亦可从皮孔一例或其附近的周皮缝隙中伸出。常簇生在插条的茎节附近或沿插条节间排列成2~3纵列。  相似文献   
4.
党常顺  兰士波  宁晓光 《安徽农业科学》2014,42(32):11379-11380,11501
以黑穗醋栗半同胞家系子代测定林为研究对象,通过探讨果实性状的遗传变异规律综合分析了数量性状的遗传效应,并以此为基础材料,系统进行了优良家系的选择。结果表明,家系间果实性状存在一定的变异,其中,果径变异较小,果穗质量变异较大,单果质量变异最大,平均变异系数分别为2.75%、32.36%和40.41%。果径和果穗质量的遗传力较强,遗传增益中等,遗传分化较小,遗传力分别为0.995和0.811,遗传增益分别为1.28%和9.67%,综合考虑各种影响因素,确定RINI07为优良家系。  相似文献   
5.
Abstract

Shoot growth as affected by plant size at planting, peat application in the planting hole, pruning, drip-irrigation and, for apple, specific apple replant disease (SARD) was investigated in apple (cv. Elstar) and blackcurrant (cvs Ben Lomond and Ben Nevis), using a multifactorial design. In the first year after planting, peat application and drip-irrigation enhanced shoot growth in both species, with a further interactional increase when both treatments were applied. The extension growth of apple, in contrast to blackcurrant, was positively related to plant size, and the strength of the relationship was distinctly improved when growth conditions were good. Pruning had only small effects on total shoot growth, with a trend towards an increase when growth conditions were poor.  相似文献   
6.
G. R. Andrews 《Euphytica》1979,28(3):751-753
Summary A rapid laboratory method was developed for screening black currant juices for ascorbic acid content in a plant breeding programme.  相似文献   
7.
Elizabeth Keep 《Euphytica》1985,34(2):509-519
Summary In black currant (Ribes nigrum) backcross progenies segregating for resistance to the gall mite, Cecidophyopsis ribis Westw. (gene Ce from Ribes grossularia L.), and to American gooseberry mildew, Sphaerotheca mors-uvae (Schw.) Berk. (gene Sph 3from R. glutinosum), significant differences in season of leafing out occurred between the resistant and susceptible classes. The data are consistent with the hypothesis that two additive genes, Lf 1and Lf 2, controlled season of leafing out and that Ce and Sph 3 were linked with Lf 1.  相似文献   
8.
E. Keep 《Euphytica》1986,35(3):843-855
Summary Cytoplasmic male sterility (cms) is described in the F1 hybrids Ribes × carrierei (R. glutinosum albidum × R. nigrum) and R. sanguineum × R. nigrum. In backcrosses to R. nigrum, progenies with R. glutinosum cytoplasm were either all male sterile, or segregated for full male fertility (F) and complete (S) and partial (I) male sterility. Ratios of F:I+S suggested that two linked genes controlled cms, F plants being dominant for one (Rf 1) and recessive for the other (Rf 2).Segregation for cms in relation to three linded genes, Ce (resistance to the gall mite, Cecidophyopsis ribes), Sph 3(resistance to American gooseberry mildew, Sphaerotheca mors-uvae) and Lf 1(one of two dominant additive genes controlling early season leafing out) indicated that Rf 1and Rf 2were in this linkage group. The gene order and approximate crossover values appeared to be: % MathType!MTEF!2!1!+-% feaafiart1ev1aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn% hiov2DGi1BTfMBaeXafv3ySLgzGmvETj2BSbqef0uAJj3BZ9Mz0bYu% H52CGmvzYLMzaerbd9wDYLwzYbItLDharqqr1ngBPrgifHhDYfgasa% acOqpw0xe9v8qqaqFD0xXdHaVhbbf9v8qqaqFr0xc9pk0xbba9q8Wq% Ffea0-yr0RYxir-Jbba9q8aq0-yq-He9q8qqQ8frFve9Fve9Ff0dme% aabaqaciGacaGaamqadaabaeaafaaakeaacaWGdbGaamyzamaamaaa% baGaaiiiaiaacccacaGGWaGaaiOlaiaacgdacaGG0aGaaiiiaiaacc% caaaGaaiiiaiaacccacaGGGaGaamOuaiaadAgaliaaigdakmaamaaa% baGaaiiiaiaacccacaGGGaGaaiiiaiaaccdacaGGUaGaaiOmaiaacs% dacaGGGaGaaiiiaiaacccacaGGGaGaaiiiaaaacaWGsbGaamOzaSGa% aGOmaOWaaWaaaeaacaGGGaGaaiiiaiaacccacaGGGaGaaiiiaiaacc% cacaGGGaGaaiiiaiaacccaaaGaamitaiaadAgaliaaigdakmaamaaa% baGaaiiiaiaacccacaGGGaGaaiiiaiaacccacaGGGaGaaiiiaiaacc% cacaGGGaGaaiiiaiaacccacaGGGaaaaiaadofacaWGWbGaamiAaSGa% aG4maaaa!6E4D!\[Ce\underline { 0.14 } Rf1\underline { 0.24 } Rf2\underline { } Lf1\underline { } Sph3\]. Crossover values of 0.36 for Ce-Lf 1, and 0.15 for Lf 1-Sph 3were estimated from the relative mean differences in season of leafing out between seedlings dominant and recessive for Ce and Sph 3.It is suggested that competitive disadvantage of lf 1-carrying gametes and/or zygotes at low temperatures may be implicated in the almost invariable deficit of plants dominant for the closely linked mildew resistance allele Sph 3. Poor performance of lf 1- (and possibly lf 2-) carrying gametes and young zygotes during periods of low temperature at flowering might also account for the liability of some late season cultivars and selections to premature fruit drop (running off).  相似文献   
9.
对茶子属中的两个最大亚属——茶子亚属和单性花亚属中部分种类的核型做了研究。结果表明,茶子亚属的8个种中有6个为二倍体(2n=2x=16),1个为单倍体(2n=1x=8),1个为四倍体(2n=4x=32),平均核型不对称系数为59.44%;单性花亚属的4个种均为二倍体(2n=2x=16),平均核型不对称系数为63.6%,由此可以看出,茶子属的进化是从染色体倍性和核型不对称性这两个方面进行的。  相似文献   
10.
英国黑加仑的栽培与研究及我国黑加仑发展策略   总被引:1,自引:0,他引:1  
概述了英国黑加仑发展历史、主栽品种、栽培面积、产量及栽培技术,介绍了在品种选育、果实与种子营养、分子标记辅助育种、转基因黑加仑、抗霜冻以及种质资源等方面的主要研究成果,分析了中国黑加仑生产优势和今后发展趋势,并提出了发展建议。  相似文献   
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