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51.
平邑甜茶后代双胚苗的倍性鉴定及核型分析 总被引:1,自引:0,他引:1
为了确定平邑甜茶双胚苗的倍性特征和核型特点,采用压片和流式细胞仪观测的方法对平邑甜茶后代中双胚苗进行染色体倍性观察和核型分析。结果表明:4株供试材料均为三倍体,2n=3x=51,染色体为小型,染色体长度比差异不大;核型组成由中部着丝点染色体(m)和亚中部着丝点染色体(sm)组成;株系8-1、8-2、12-1和12-2的核型公式分别为2n=3x=45m+6sm,2n=3x=48m+3sm,2n=3x=27m+24sm,2n=3x=33m+18sm;染色体相对长度和着丝点指数的变异范围分别为1.21%~2.68%和34.19%~42.37%,1.44%~2.63%和35.59%~44.08%,1.36%~3.02%和32.85%~42.18%,1.43%~2.87%和34.23%~44.02%;核型分别属于1B、1A、2B和1B类型,表现为株系之间的核型不完全相同。本研究为丰富无融合生殖型砧木的育种理论,获得新的苹果无融合生殖型砧木提供有益的借鉴。 相似文献
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Alteration in important quality traits and antioxidant activities in Brassica oleracea with Ogura cybrid cytoplasm 下载免费PDF全文
Shyam S. Dey Reeta Bhatia Chander Parkash Saharsh Sharma Manish Dabral Vibha Mishra Ila Bhardwaj Komal Sharma Vinod Kumar Sharma Raj Kumar 《Plant Breeding》2017,136(3):400-409
In vegetable brassicas, cytoplasmic male sterility (CMS) system is the most preferred mechanism for hybrid seed production and Ogura cybrid cytoplasm is the only source used widely. Effects of the alien cybrid cytoplasm on important quality traits need to be understood for their effective use in breeding programme. In analysing 38 Ogura cybrid cytoplasm‐based cauliflower CMS lines, it was revealed that introgression of Ogura cytoplasm resulted in significant alteration in important quality traits. Cupric reducing antioxidant activity and ferric reducing ability of plasma values were increased up to 5–10 times in different genotypes. Among 38 analysed CMS lines, concentration of plant pigments such as anthocyanin, total chlorophylls and ascorbic acid was reduced in 21, 17 and 32 genotypes, respectively. However, the concentration of total carotenoids and β‐carotene was elevated in most of the CMS lines and total carotenoid was increased up to 20 times in the CMS line, Ogu13‐85‐2A. The results indicate the role of nuclear–cytoplasmic interaction and mitochondrial genome in determining concentration of different quality traits. 相似文献
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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
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Wild olive (Olea europaea subsp. europaea var. sylvestris) is an important component of Mediterranean forests and a key genetic source for olive improvement programmes. Since 2009, a severe decline caused by Phytophthora cryptogea and P. megasperma has been detected in a protected wild olive forest of high ecological value (Dehesa de Abajo, Seville, Spain). In this natural forest, sampling of roots and soil was carried out on 25 wild olives with symptoms in 2014 and 2015. Apart from the already known P. cryptogea A1 and P. megasperma, a third Phytophthora species was consistently isolated from wild olive rootlets with symptoms. These isolates conformed morphologically with the newly described species P. oleae and were confirmed by analysis of their ITS regions and cox1 sequences. Temperature–growth relationships showed a maximum growth at 19.9 °C on carrot agar medium, making it the lowest temperature Phytophthora species infecting wild olive roots. Pathogenicity was confirmed on 1-year-old healthy wild olive seedlings and was similar to the previously known pathogenic phytophthoras. As temperature requirements are quite different, the three Phytophthora species may be active against wild olive roots in different seasons. However, the prevalence of P. oleae infecting wild olives in recent years could be due to its introduction as a new invasive pathogen. The probable invasive nature of P. oleae, together with increasing rain episodes concentrated in short periods frequent in southern Spain, would allow the outbreak of infections in wild olive forests, and also put cultivated olive orchards at risk. 相似文献
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菠萝栽培种(Ananas comosus var. comosus)的营养生长期较长,制约了其新品种选育效率。收集和筛选营养生长期较短的种质,可为短营养生长期菠萝新品种的选育创制中间材料。从境外收集了23份易成花的野生种质材料,自2008年起进行栽培、繁殖和性状鉴定。通过对营养生长期的比较和观察,从矮凤梨(A. comosus var. nanus)的体胚苗中发现了1份营养生长期显著缩短的突变材料‘14-1’,其营养生长期约6个月(原品种约12个月),1年开花2次,具有极易成花等特点。‘14-1’无性繁殖后代遗传性状稳定,可作为短营养生长期菠萝育种的亲本资源。 相似文献
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通过测定具有代表性的四种室内环境条件下银心吊兰的固碳释氧量、释水量的变化,研究了银心吊兰叶片生长与环境条件相互作用,结果表明:在南向阳光充足的窗边,银心吊兰的固碳释氧量和释水量最大,但叶片生长较慢;光强稍弱的东向窗边,叶片生长较快,但固碳释氧量和释水量低于南向窗边;阴暗的条件下叶片的生长受到抑制,改善环境能力严重降低。 相似文献
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以14C为示踪剂,用14CO2+CO2法对2年生黄柏进行半株标记,在主干上环状剥去韧皮部,以塑料薄膜包裹,燃烧法制样、液体闪烁测量法测14C活度。结果表明,未剥皮黄柏韧皮部的14C同化物运输速率为52.0cm/h,3h左右同化物从树冠运输到根系,树冠不同部位的功能叶14C同化物分配为:中部功能叶>上部功能叶>下部功能叶;剥皮后,同化物分配规律改变为:上部功能叶>中部功能叶>下部功能叶;剥皮第15天在新生韧皮部、剥口下方的树皮及根系中检测到14C同化物,表明新生韧皮部的生理功能得到恢复。 相似文献