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81.
82.
[目的]研究药用植物灵菊七(Gynura medica)的细胞染色体特点,并对其染色体核型进行分析。[方法]以灵菊七幼苗茎尖为材料,从上午6:30~10:30,每隔20 min取材一次,采用常规制片技术制片,显微镜观察中期分裂相细胞,对染色体完全分散开的细胞进行染色体计数及核型分析。[结果]在染色体分散良好的102个中期分裂相细胞中,有96.08%含20条染色体,3.92%含40条染色体;同时结果表明上午7:50~9:30取材较佳。[结论]G.medica为二倍体植物,体细胞含有10对染色体,核型公式为2n=2x=20 m,染色体核型属于1A型。该研究结果为国内首次报道。 相似文献
83.
建立了致病性大肠埃希氏菌脉冲场凝胶电泳图谱。采用脉冲场凝胶电泳技术分离细菌DNA,EB染色,Info Quest FP聚类分析软件分析,结果获得了《中国兽医菌种目录》中收录的127株致病性大肠埃希氏菌脉冲场凝胶电泳图谱,其中CVCC212与CVCC213等12对大肠埃希氏菌脉冲场凝胶电泳图谱相似率在85%以上。实验通过建立127株致病性大肠埃希氏菌脉冲场凝胶电泳图谱,丰富了致病性大肠埃希氏菌背景资料,为进一步分析基因分型与致病性之间的关系提供了实验数据。 相似文献
84.
以接骨木Sambucus williamsii Hance的根尖为材料,采用常规制片法,用Schiff’s进行孚尔根染色,对接骨木根尖生长点细胞的染色体进行观察和显微摄影。同时对接骨木进行核型分析,为其植物资源的开发,良种的选育和分类提供了细胞学方面的依据。 相似文献
85.
《Plant Production Science》2013,16(4):457-465
AbstractDrought and waterlogging that occur sequentially under field conditions are important abiotic stresses affecting plant growth and development. The ability to maintain the root system development during the contrasting moisture stresses may be one of the key traits for plant adaptation. This study aimed to identify the key root traits that contributed to the above ability by comparatively examining the effects of the two moisture stresses in succession on root system development. The chromosome segment substitution lines (CSSLs) from the crosses between the japonica rice cultivar Nipponbare and indica rice cultivar Kasalath were used for precise comparison of root system development. The rice seedlings were grown by hydroponics under a continuously well-aerated condition for 14 days (non-stressed), a drought condition for 7 days followed by an oxygen (O2)-deficient (stagnant) condition for 7 days (drought-to-stagnant, D-S), or a stagnant condition for 7 days followed by drought condition for 7 days (stagnant-to-drought, S-D). CSSL43 and 47 did not show any significant differences in growth from Nipponbare under the non-stressed condition, but exhibited greater lateral root production under the stresses. Lateral root production was most closely related to faster seminal root elongation mediated by higher aerenchyma formation in the D-S condition, and to more branching of lateral roots on the seminal root axis in the S-D condition. The D-S condition severely affected lateral root production due to reduced seminal root elongation and aerenchyma formation. These results confirmed the fact that those root traits previously identified using different cultivars greatly contribute to plant adaptation. Oxygen deficiency preceded by drought (D-S) was more stressful to roots than drought preceded by O2 deficiency (S-D), because drought reduced root aerenchyma formation during the subsequent stagnant condition. 相似文献
86.
87.
为了明确南麦号系列小麦品种及其亲本的染色体结构特点,用4种寡核苷酸探针和非变性荧光原位杂交(ND-FISH)技术对南麦号小麦品种及其亲本的染色体进行了分析。结果表明,亲本攀早抗含1RS/1BL易位染色体,它的4个衍生品种中3个含1RS/1BL易位染色体。寡核苷酸探针Oligo-275.1、Oligo-275.2、Oligo-pSc119.2-1和Oligo-pTa535-1反映出了2A、4A、5A、6A、7A、3B、5B、6B、1D和2D染色体在攀早抗及其衍生品种间的结构差异。根据Oligo-275.1和Oligo-275.2的信号模式,推测7A染色体在南麦302、特研麦南88和荣春南麦1号中的重组情况不同。 相似文献
88.
Ravindra DONDE Jitendra KUMAR Gayatri GOUDA Manoj Kumar GUPTA Mitadru MUKHERJEE Sk Yasin BAKSH Pradosh MAHADANI Khirod Kumar SAHOO Lambodar BEHERA Sushanta Kumar DASH 《水稻科学》2019,26(4):239-247
The introgression of wild chromosomal segments into popular rice varieties is one of the potential approaches for developing varieties for drought stress condition. Sixteen genotypes, including nine indica, two tropical japonica and five chromosome segments substitution lines(CSSLs) with different levels of tolerance/susceptibility to drought stress, were selected for diversity study. Sixty-three microsatellite markers were utilized for assessing genetic diversity. A total of 95 alleles were amplified, and out of them, 60 were polymorphic. Six unique alleles, amplified by the microsatellite loci RM276, RM472,RM488, RM537, RM541 and RM28089, were identified in six genotypes, namely FR13A, Brahamanakhi,RUF44, Swarna-sub1, Brahamanakhi and Satyabhama. The highest genetic similarity was found among CSSLs. Polymorphism information content(PIC) value varied from 0 to 1.00 with an average of 0.66 per locus. Twenty-eight microsatellites were found to be polymorphic, which could be used in marker-assisted selection programme. All the sixteen genotypes were grouped into two major clusters at genetic similarity of 0.64. In the cluster I, five CSSLs identified as diverse genotypes had wild ancestor segments responsible for drought tolerance, and hence they could be utilized as potential donors. The popular Indian varieties, Swarna-sub1 and IR64-sub1, could be used as recurrent parents in the future breeding program for developing varieties for abiotic stresses such as submergence and drought. 相似文献
89.
基于寡核苷酸探针套painting的染色体鉴定技术简单、经济和高效, 可以促进小麦品种及亲缘物种染色体识别和变异体鉴定, 提高染色体工程效率。我们前期开发了寡核苷酸探针套, 包含pAs1-1、pAs1-3、AFA-4、(GAA)10和pSc119.2-1共5个探针。本研究通过一次荧光原位杂交(FISH), 对源于17个非整倍体的18份材料分析发现, 其中14个染色体组成正确, 可以清晰识别相应的缺体、四体和端体。还构建了基于寡核苷酸探针套涂染的、能准确识别3个基因组和7个部分同源群染色体的高清核型, 发现4个非整倍体发生变异, 其中从N5BT5D中鉴定出一个可能的小片段相互易位系T6AS·6AL-6DL和T6DS·6DL-6AL。进一步对7个地方品种、10个栽培品种(系)和1个人工合成小麦分析, 发现15条染色体存在多态性, 涉及6条B组(除4B)、5条A组(除1A和3A)和4条D组(1D、2D、4D和7D)染色体, 可以清晰识别我国小麦生产上广泛应用的3种易位类型(T1RS·1BL、T6VS·6AL及相互易位T1RS·7DL和T7DS·1BL), 省去了基因组原位杂交(GISH)程序。另外, 对5个亲缘物种分析发现, 该探针套可以识别栽培一粒小麦、硬粒小麦Langdon、荆州黑麦、长穗偃麦草(2n=2x=14)全部和中间偃麦草30条染色体, 并构建了这5个物种的核型。本研究结果证实该寡核苷酸探针套可以有效用于小麦及亲缘物种染色体鉴定, 高清晰的中国春非整倍体核型为小麦染色体工程提供了参考标准。 相似文献
90.
To provide food and nutrition security for a growing world population, continued improvements in the yield and nutritional quality of agricultural crops will be required. Wheat is an important source of calories, protein and micronutrients and is thus a priority to breed for improvements in these traits. The GRAIN PROTEIN CONTENT-B1 (GPC-B1) gene is a positive regulator of nutrient translocation which increases protein, iron and zinc concentration in the wheat grain. In the ten years since it was cloned, the impacts of GPC-B1 allelic variation on quality and yield traits have been extensively analyzed in diverse genetic backgrounds in field studies spanning forty environments and seven countries. In this review, we compile data from twenty-five studies to summarize the impact of GPC-B1 allelic variation on fifty different traits. Taken together, the results demonstrate that the functional copy of the GPC-B1 gene is associated with consistent positive effects on grain protein, Fe and Zn content with only marginally negative impacts on yield. We conclude that the GPC-B1 gene has the potential to increase nutritional and end use quality in a wide range of modern cultivars and environments and discuss the possibilities for its application in wheat breeding. 相似文献