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111.
Chromosome doubling in Tripsacum: the production of artificial, sexual tetraploid plants 总被引:1,自引:0,他引:1
O. Leblanc M. Dueñas M. Hernández S. Bello V. Garcia J. Berthaud Y. Savidan 《Plant Breeding》1995,114(3):226-230
A collection of embryogenic diploid calli of Tripsacum was established and treated with colchicine to induce chromosome doubling. Sections containing duplicated cells in calli were identified using flow cytometry and ploidy level was determined in the regenerated plantlets. Tetraploid plants from several origins were obtained. In contrast to wild polyploid plants, which show apomictic development, the regenerated tetraploid plants reproduced sexually. By hybridizing these plants with wild tetraploid apomicts, various populations were established; these will allow a study of the inheritance of apomixis in Tripsacum. 相似文献
112.
Summary Studies were made of the presence and frequency of occurrence of gliadin bands 42 and 45 in three samples of Aegilops sharonensis Eig and 59 samples of wild tetraploid wheat (Triticum dicoccoides
Korn.) from natural distributions of these species in Israel.Two samples of Ae. sharonensis possessed a band in position 45 and one possessed no bands corresponding to either band 45 or band 42. In T. dicoccoides, band 45 was either present or not and 42 was always absent. In its grassy and intermediate growth habit forms, (believed to be more primitieve than the cercal forms) band 45 appeared to be more frequent than in the cereal form.The presence of band 45 in the Ae. sharonensis, and its relatively high frequency in T. dicoccoides, populations from Mt. Hermon (likely to be relatively free from introgression from cultivated tetraploid wheat) indicate the likelihood of a primary origin of the allele coding for band 45. The absence of band 42 from all Ae. sharonensis and T. dicoccoides populations in this study, indicates a more recent evolutionary origin of the allele coding for this band, possibly arising as a mutation during the domestication of tetraploid wheat.The results have implications for breeding programmes in tetraploid wheat. 相似文献
113.
Summary The meiotic behaviour of five tetraploid wheat strains x Elytricum fertile (2n=42 chromosomes, AABBD(SH) genomes) F1 hybrids has been analysed. Multivalent associations were observed in the hybrids which could be attributed to Elymus sibiricus L. gene (s) somewhat suppressing the activity of the wheat homoelogous pairing control system. This interaction depends on the wheat genotype. The effect was particularly notable when Triticum turgidum var. salomonis was the wheat parent. The possibility of gene transfer from Elymus to wheat is discussed. 相似文献
114.
Summary In the synthesis of primary hexaploid triticale, a cross-incompatibility barrier exists when tetraploid wheat (4X) is crossed with diploid (2X) rye. Fertilization may occur, however, abnormal endosperm development usually leads to premature embryo death. Four selected tetraploid wheat lines were crossed as females with seven open-pollinated rye lines and the resulting embryos were rescued in vitro 13–16 days after pollination. The wheat genotypes showed a major influence on crossability (seed set), embryo development and plant recovery. The highest efficiency of amphihaploid plant recovery (18.3 plants per 100 pollinated florets) was obtained from one 4X wheat line originally selected from the cross T. carthlicum × T. dicoccoides. Some of the 3X amphihaploid plants (ABR) derived from two wheat lines showed relatively high level of partial fertility presumably as a result of meiotic restitution. Correlation analysis showed that crossability (seed set), normal hybrid embryo development in vivo and embryo culturability were independent of each other. 相似文献
115.
在本研究中,首先在二十个籼粳亚种四倍体水稻F1代中筛选出高结实杂交组合:Dur/Sg9912 (命名为PSR120),然后在田间随机取样的200多株PSR120F2代植株,并考察其结实率。用统计软件分析结实率,结果表明,多倍体水稻F2结实率变异大,分布不对称。 相似文献
116.
秋水仙素对离体培养辣木多倍体的诱导 总被引:1,自引:0,他引:1
以印度辣木栽培品种PKM(Moringa oleifera PKM-1)一年生植株茎尖为外植体,采用秋水仙素结合组织培养技术诱导多倍体的方法,研究了秋水仙素浓度及处理时间对诱导染色体倍性变异的影响,以及不同外源植物生长调节剂浓度对茎段培养的增殖影响,结果表明:辣木芽初代培养的最适培养基为MS+6-BA2.0mg/L+NAA0.2mg/L,不定芽增殖的最佳培养基为MS+6-BA0.6mg/L,增殖系数为3.57,用0.1%秋水仙素处理24h左右,可诱导获得四倍体再生植株。 相似文献
117.
生姜四倍体抗热性与抗寒性的初步研究 总被引:3,自引:0,他引:3
对生姜四倍体与二倍体用低温高温处理后,以生长恢复试验和细胞膜透性测定法对二者进行抗热性和抗寒性比较。结果表明:在0℃,2.5℃,25℃,50℃,93℃各温度条件下二者叶片的电导率、膜伤害率以及生长恢复状况均有较大差异,初步证明四倍体植株的抗热性和抗寒性比二倍体植株强。 相似文献
118.
119.
120.
君子兰未成熟胚四倍体诱导及染色体数鉴定 总被引:2,自引:0,他引:2
以君子兰(Clivia miniata Regel.)品种‘胜利’为试材,采用一种新型外植体未成熟胚,利用秋水仙素与组织培养相结合的方法,研究秋水仙素浓度、处理时间和不同胚龄对未成熟胚诱导加倍的影响。结果表明:在MS + NAA 2.0 mg · L-1 + BA 1.5 mg · L-1培养基上,0.01%秋水仙素处理180 d胚龄的未成熟胚20 d诱变效果最佳,四倍体诱变率最高,达30.8%,形态变化率达36.5%,死亡率为34.1%。经0.03%秋水仙素处理120 d胚龄的未成熟胚30 d诱变效果也较好,四倍体诱变率较高,达24.0%,形态变化率达21.1%,死亡率为46.7%。经染色体数观察,加倍处理后代中存在2x、4x和混倍体植株。随机调查了267株加倍处理植株,得到30株四倍体(2n = 4x = 44)、194株二倍体(2n = 2x = 22)和43株混倍体,平均四倍体诱变率为11.2%。秋水仙素处理出现的植株生长缓慢,生根明显较晚,叶片变宽变短等形态变化可以作为加倍的初期有效判断指标。 相似文献