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111.
普通小麦辉县红-荆州黑麦异染色体系的选育及其梭条花叶病抗性鉴定 总被引:3,自引:1,他引:3
为发掘和利用荆州黑麦所携抗梭条花叶病基因,综合利用分子细胞遗传学与分子标记技术结合多年抗性鉴定,从高感梭条花叶病小麦地方品种辉县红与荆州黑麦杂交后代(F7~F9)中选育出二体异附加系5个(分别添加1R、2R、R3、5R和R7)、5RS端二体异附加系1个和多重异附加代换系2个(染色体组成分别为20’’+2R(2D)’’+4R’’和19’’+1R(1B)’’+2R(2B)’’+4R’’)。鉴定表明,双二倍体荆辉1号高抗梭条花叶病,表明黑麦抗性基因可在小麦背景中稳定表达,2R、R7二体异附加系及2个含2R的多重异附加代换系均表现高抗,推测2R和R7上可能携带抗病基因。这些材料是研究荆州黑麦抗性基因遗传及小麦抗病育种的新种质。 相似文献
112.
关于水稻穗芽的生理学研究 总被引:12,自引:0,他引:12
利用重组自交系籼稻中-156/谷梅2号304份株系为材料,在田间条件下营造高温、高湿的小气候,以“穗穗芽率”及“粒穗芽率”为指标,筛选易发生穗芽与不易发生穗芽的极端材料,比较研究重组自交系亲本与各供试株系籽粒在穗芽发生期间的生理差异。结果表明,该重组自交系母本谷梅2号比父本中-156易穗芽,在正常成熟过程中籽粒内源GA1含量水平高于中-156,ABA含量水平低于中-156;谷梅2号籽粒淀粉酶活性也高于中-156。花后15 d至完熟的籽粒灌浆期如遇高温、高湿条件,谷梅2号及易穗芽的株系籽粒内源GA1随雨日渐增,增幅高于中-156及不易穗芽的株系,同时其淀粉酶活性回升,在正常成熟过程中花后15 d后籽粒中淀粉酶活性与日渐降,但其幅度远高于父本中-156及不易穗芽的株系,这种变化可能是易穗芽的亲本与株系对高温、高湿敏感诱发穗上发芽的主要生理基础。 相似文献
113.
不同施肥水平对油菜胞质雄性不育系07A和杂一代品种川油12育性影响研究 总被引:5,自引:0,他引:5
以甘蓝型油菜polima细胞质雄性不育(CMS)系07A和杂一代品种川油12号为材料,连续两年采用四元二次回归正交旋转组合设计,研究了氮、磷、钾、硼不同施用量对上述材料育性的影响。结果表明:(1)不育系的不育度和杂一代的恢复度均受年度间气候变化的影响,同一材料在年度间有不同的表现,对各元素施用量的反映也不尽相同;(2)施用过多的氮肥会降低07A的不育度和杂一代的恢复度,而增施磷、钾、硼肥可提高不育 相似文献
114.
115.
黔油12号双低杂交油菜制种技术研究Ⅲ.父母本不同行比群体经济性状变化及制种产量 总被引:7,自引:7,他引:7
为制定黔油12号大面积制种技术方案,明确黔油12号制种时父母本的适宜行比,试验父母本行比共设1:2、1:4、1:6、1:8、1:10、1:126个处理进行研究.结果表明:(1)因行比不同,单位面积上母本不育株数差异较大,行比1:6和1:8的不育株数较行比1:4的分别多124株和342株,行比1:10和1:12的不育株数比行比1:4的分别多461株和551株;(2)考察距父本行不同距离的母本行的经济性状,以距父本行第一行和第二行的全株有效角较多,距父本三行以上的千粒重高,但每角实粒数减少,单株产量随与父本距离加大而降低;不同行比母本群体经济性状以行比1:2~1:6的全株有效角较多,随行比加大,群体的平均每角实粒数减少,千粒重增加,单株产量逐渐降低.(3)在相同面积条件下,制种产量以行比1:6至1:10为佳,其中1:8的产量居第一位,为51.50kg/667m2;1:10的产量居第二位,为51.23kg/667m2;1:6的产量居第三位,为50.03kg/667m2. 相似文献
116.
117.
Twelve primary hexaploid triticale (X Triticosecale Wittmack), synthesized from, three lines of tetraploid wheat (Triticum durum L., T. turgidum L.) and four inbred lines of rye (Secale cereale L.), were used to produce 18 crosses with homozygous wheat and heterozygous rye genome and 12 crosses with heterozygous wheat and homozygous rye genome. Parents and crosses of triticale, wheat, and rye were tested for two years (rye for one year only) in two-replicate block designs with 1 m2-plots. Data were assessed for plant height, grain yield and for yield-related traits. Performance of triticale crosses was considerably lower than that of the wheat and rye crosses. The amount of heterosis varied greatly between years. Positive and mainly significant heterosis was revealed in triticale generations F1 and F2. The average values were closer to those in wheat than to those in rye. For most characters a high level of heterosis was retained in tnucalt1 generation F2. Heterozygosity of the wheat and rye genome both contributed to heterosis in triticale. However, gene action of the rye genome strongly depended on the homozygous wheat background: one wheat line almost completely suppressed and another greatly stimulated the heterotic effect of the rye genome. In the later case, the amount of heterosis was related to that in rye per se. Information from hybrid rye breeding may therefore be used when establishing gene pools for hybrid breeding in triticale. 相似文献
118.
The aim of this work was to evaluate the leaf rust resistance introduced into introgressive triticale lines with Triticum monococcum genes, and to study the expression of these genes at the hexaploid level. The introgressive lines were developed by incorporating diploid wheat (T. monococcum s.s.) genes into hexaploid triticale LT 522/6 using the synthetic allotetraploid T. monococcum/Secale cereale (AmAmRR) as a bridging form. A group of 44 those lines, parental stocks and check cultivars were inoculated at the seedling stage (in a greenhouse) and at the adult‐plant stage (in the field) with four pathotypes of Puccinia triticina. At the seedling stage the assessment of infection type showed that four lines had resistance to all pathotypes as high as in the T. monococcum donor. Adult plant examinations showed some introgressive lines with complete resistance and also lines with partial resistance, expressed in area under the disease progress curve (AUDPC) calculations as slow rusting. Some lines comprise low AUDPC with complete resistance at seedling stage. 相似文献
119.
Homoeological relationships between the f chromosome of Brassica rapa and the e chromosome of Brassica oleracea 总被引:1,自引:0,他引:1
Eight plants of the putative double monosomic addition line (DMAL, 2n= 20) were developed by crossing a monosomic chromosome addition line of radish [f(A)‐type monosomic addition line (MAL) (2n= 19)] carrying the f chromosome of Brassica rapa (2n= 20, AA) with another [e(C)‐type MAL (2n= 19)] having the echromosome of Brassica oleracea (2n= 18, CC). The homoeological relationships between the two alien chromosomes were investigated by morphological, cytogenetic and random amplified polymorphic DNA (RAPD) analysis. Seventeen morphological traits that were not present in the radish cv. ‘Shogoin’ were observed in both MALs and these traits were substantially exhibited in DMAL plants. At the first metaphase of pollen mother cells (PMCs), the two parental MALs showed a chromosome configuration of 9II +1I, demonstrating impossibility of recombination between the R and the added chromosomes. The DMALs formed 10II in approximately 73% of PMCs, with one bivalent showing loose pairing between two chromosomes differing in size. In an attempt to identify the two MALs by RAPD‐specific markers using 26 selected random primers, 13 and 20 bands were specific for the f(A)‐type and the e(C)‐type MALs, respectively; 12 bands were common to both MALs (26.7%). In conclusion, the f chromosome of B. rapa is homoeologous to the e chromosome of B. oleracea. The genetic domain (genes) for 17 morphological traits are linked to each homoeologous chromosome bearing 27% of the corresponding RAPD markers. 相似文献
120.
Oligonucleotide fingerprinting of tomato DNA 总被引:6,自引:0,他引:6
D. Kaemmer K. Weising B. Beyermann T. Börner J. T. Epplen G. Kahlm 《Plant Breeding》1995,114(1):12-17
Hinfl -digested DNA samples of wild and cultivated species of tomato were hybridized in gel to different oligonucleotide probes complementary to simple-sequence repeats. All motifs tested i.e. (GATA)4, (GGAT)4, (CA)8. (CAG)5, (GTG)5, (GAAGTGGG)2 and (CCTA)4, produced multilocus fingerprints in all tomato species and cultivars. The extent of inter- and intraspecific polymorphism of the banding patterns varied considerably between different probes, with (GGAT)4, (CCTA)4, (GATA)4 and (CA)8 showing a much higher discriminatory potential than the other probes. Cluster analysis of band-sharing data yielded dendrograms which were consistent with the known history of tomato cultivation. (GATA)4 was also successfully used for purity testing of breeding lines, as well as for analysing an F1 progeny of a cross between two lines. 相似文献