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71.
Colchicine-induced chromosome doubling in Platanus acerifolia and its effect on plant morphology 总被引:1,自引:0,他引:1
We report the production of tetraploid plants of Platanus acerifolia, with the ultimate aim of improving the ornamental qualities of this important urban landscaping tree. Chromosome doubling
was achieved by the application of colchicine to either pre-soaked seed or to the apical meristems of young seedlings. Treatment
of the ungerminated seed was the more efficient method in terms of numbers of tetraploid seedlings (up to 40%, as determined
by chromosome counting of the root-tip nuclei) but this method produced no mature tetraploid plants due to the deleterious
effect of colchicine on subsequent root growth. When colchicine was applied directly to the apical growing tip of cotyledon-stage
seedlings, leaf and stem growth was temporarily affected but the plants eventually recovered. We conducted a preliminary screen
for putative tetraploids based on the observation in other plant species of a correlation of stomatal size and distribution
with ploidy. Plants containing significantly larger stomata and at a lower density across the lower leaf epidermis, were selected
for further analysis by flow cytometry and chromosome counting. These techniques confirmed that, of the 12 putative polyploids,
four were tetraploid, five were mixoploid and three were, in fact, diploid. Morphological differences of the tetraploids included
a more compact growth habit and broader, thicker leaves. These plants are being grown to full maturity in order to test their
potential for use in a breeding programme aimed at producing sterile triploid lines. 相似文献
72.
小麦7D染色体数量性状基因定位和效应估计的研究 总被引:10,自引:0,他引:10
综合应用方差分析法、区间定位法和联合定位法将控制抽穗期、有效穗数、小穗数、50粒重和单穗产量等5个性状的6个数量性状基因座(QTL)定位在小麦7D染色体上。其中控制粒重的QTL有2个。这些QTL集中分布在着丝粒附近和染色体长臂的末端两个区域。效应估计结果表明多数QTL的效应是微效的,控制同一个性状(粒重)的两个QTL的效应几乎相等。比较3种QTL定位法的分析结果,方差分析简单有效,且当染色体上只有 相似文献
73.
Summary Fifteen lines of triticale were studied using the C-banding staining method. A typical, complete chromosomal complement was found in 11 lines, while the remaining lines demonstrated some variations. A slight modification in the technique is discussed.Supported in part by CSRS/USDA Grant No. 801-15-03A. 相似文献
74.
大麦幼胚培养再生植株及其后代的细胞遗传学研究 总被引:3,自引:0,他引:3
从5个普通大麦品种的幼胚培养中均得到体细胞再分化植株。对214棵再生植株进行了细胞学检查,发现四倍体5株,占总数的2.3%;相互易位杂合体1株,占总数的0.46%。四倍体植株虽然得到少数大而瘪的种子,但它们次年没有发芽;易位杂合体减数分裂时的染色体构型为5Ⅱ+1Ⅳ,属于两对非同源染色体间的简单易位。其余所有二倍体植株的细胞 相似文献
75.
Starch biosynthesis in plants involves the concerted action of a numberof enzymes, including ADPglucose pyrophosphorylase, starch synthases,branching enzymes and debranching enzymes. We report on the cloningand characterisation of genes encoding these enzymes from wheat and ontheir chromosomal locations. The prospects for manipulating wheat starchstructure and functionality using these genes is discussed. 相似文献
76.
陆地棉与三裂棉、斯特提棉和A111种间杂种F1的形态与细胞学 总被引:2,自引:0,他引:2
本文研究了TM-1×三裂棉、江苏棉1号×斯特提棉、泗棉2号×Alll 3个种间杂种F_1的主要形态特征及花粉母细胞减数分裂中期Ⅰ的染色体行为。3个种间杂种F_1的花器官性状大多趋向于父本野生棉,如花冠颜色、花心等;营养器官大多趋向于中间型,如叶色、叶形等。杂种F_1均表现高度不育。减数分裂中期Ⅰ的染色体构型依次为:13.73Ⅰ 12.52Ⅱ 0.03Ⅲ 0.04Ⅳ,28.03Ⅰ 5.38Ⅱ 0.07Ⅲ和33.26Ⅰ 2.87Ⅱ;其染色体组亲和性指数分别为0.9715、0.4192和0.2208。这一结果表明:(1)陆地棉与三裂棉的亲缘关系较近,与斯特提棉的亲缘关系较远,与Alll的亲缘关系更远;(2)泅棉2号×Alll的F_1染色体数为2n=3x=39,其染色体数x=13与棉属相同,其次因Alll原产于澳大利亚,形态上与纳尔逊氏棉、澳洲棉比较接近,因此推测它可能属于棉属的C染色体组种。 相似文献
77.
Zhi-Shan Lin Zhi-Fu Cui Xiang-Yan Zeng You-Zhi Ma Zeng-Yan Zhang Toshiki Nakamura Goro Ishikawa Kazuhiro Nakamura Hisashi Yoshida Zhi-Yong Xin 《Euphytica》2007,158(1-2):109-118
Chromosome compositions of seven lines, derived from hybrids between a wheat cultivar and the wheat-Thinopyrum intermedium addition line Z6, with barley yellow dwarf virus (BYDV) resistance, were determined by genomic in situ hybridization, cytogenetic and SSR assays. The results showed that
line N522 was a disomic addition line, lines N420 and N439 were 2Ai-2(2B) chromosome substitution lines, lines N431 and N452
were 2Ai-2(2D) chromosome substitution lines, line N523 was a 2Ai-2S(2D) ditelosomic substitution line, and line N530 was
a double ditelosomic line with the mitotic chromosome number of 2n = 40 + 4t. One pair of telosomes in line N530 lacked several proximal SSR markers of chromosome 2AS, but possessed certain
terminal markers, which were consistent with an acrocentric structure, and the other pair of chromosome arms were presumably
2Ai-2S telosomes with BYDV-resistance. These wheat-Th. intermedium lines provide useful genetic resources for developing alien chromosome translocation lines. 相似文献
78.
稻属间杂种花粉植株的细胞遗传学研究 总被引:1,自引:0,他引:1
以栽培稻02428与紧穗野生稻间不育F1杂种(2n=24,AC)为材料进行花约培养,共接种花约32688个,获得再生绿苗13株及白化苗两株,愈伤诱导率与分化率分别为0.14%和34.78%。有9朱花粉绿苗长至成熟,均表现长芒、紫柱头、强感光及易落粒等野生亲本的特性。细胞学结果进一步表明,其中4株为二倍体(2n=24),形态上琚的F1杂种相似,花粉母细胞中期Ⅰ亦只能见到少数二价体;另5株则为四倍体( 相似文献
79.
Duplication of the Bx7 high-molecular-weight glutenin subunit gene in bread wheat (Triticum aestivum L.) cultivar'Red River 68' 总被引:5,自引:0,他引:5
SDS-PAGE analysis of seed proteins of the cultivar‘Red River 68’showed a considerably higher staining intensity of the band corresponding to HMW-GS Bx7 relative to the equivalent band in the cultivars‘Chinese Spring’and‘Cheyenne’. Southern blots of restriction enzyme fragments from DNA of these three cultivars were analyzed densitometrically to reveal that the band corresponding to the Bx7 gene of‘Red River 68’had a double staining intensity compared to the equivalent bands from the other two cultivars, which indicates that in‘Red River 68’a duplication of the Bx7 gene has occurred. Although the possibility of the gene copy being a pseudogene was not ruled out, the greater amount of protein corresponding to Bx7 in‘Red River 68’most likely is in accord with an increase in active gene number. SDSPAGE analysis of the proteins showed also that the mobility of Bx7 in‘Cheyenne’was slightly different from the mobilities of the Bx7 subunits of‘Red River 68’and‘Chinese Spring’. The same difference was observed at the gene level by PCR amplification of the genes encoding these subunits. 相似文献
80.