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61.
水稻剑叶角度与主穗产量的遗传剖析 总被引:2,自引:0,他引:2
理想水稻株型的选育与高产育种密切相关,而剑叶角度则是构成水稻理想株型的重要指标之一,同时也是影响水稻产量的重要因素。合理开发利用水稻中控制剑叶角度及产量相关的数量性状基因座位(QTL),并结合分子育种技术,可更好地为高产制繁种目标服务。通过应用由244个株系组成的珍汕97B/密阳46重组自交系(RIL)群体,构建含256个分子标记的连锁图谱,采用QTL区间作图法对剑叶角度及主穗产量等5个性状进行定位分析,共检测到17个QTL,分布于染色体1、2、3、5、6、9、10、11。这些QTL对相应性状的贡献率介于3.46%~25.64%之间。在第1染色体上检测到控制5个性状的QTL,其中控制剑叶角度的两个QTL;在第2、3、9、10、11染色体上分别检测到各一个QTL;第5染色体上检测到控制剑叶、每穗总粒数和每穗实粒数的3个QTL;1个每穗实粒数和2个每穗实粒重的QTL分布于第6染色体上。多个区间表现出对两个性状的显著作用,其中第1染色体2个,第6染色体1个。相关性分析表明,较小的剑叶角度可通过提高结实率进而显著增加产量。 相似文献
62.
重组鹿肉制品的加工特性 总被引:4,自引:0,他引:4
该文以不同营养、风味和加工特性的鹿肉和猪肉为原料,加非肉蛋白等营养强化物质,借谷氨酰胺转胺酶(TG)的粘合交联作用研制营养风味俱佳的重组鹿肉制品.单因素试验得出各因素对重组特性(剪切力、拉伸强度和蒸煮损失)的影响:TG-B(含1%TG、99%蛋白质)作用效果优于TG-A(含0.5%TG、99.5%蛋白质);大豆蛋白对重组特性和品质的作用效果优于脱脂麦胚蛋白、乳清蛋白、酪蛋白酸钠等非肉蛋白;TG-B的作用温度和时间、食盐和复合磷酸盐对嫩度和持水性的影响显著.借因子分析法和Plackett-Burman(PB)设计筛选出影响肉制品重组效果的主要因素为TG-B作用温度、食盐和大豆蛋白;运用中心组合设计和响应曲面分析优化出重组肉制品的最佳工艺参数为TG-B 0.5%、复合磷酸盐0.4%、食盐2%、大豆蛋白4.1%、42℃反应30 min、80℃灭酶20 min. 相似文献
63.
Metal resistance genes are valuable resources for genetic engineering of bioremediation tools. In this study, novel genetic determinants involved in cadmium (Cd) resistance were identified using a small-insert metagenomic DNA library constructed from an arable soil microbiome. A total of 16 recombinant plasmids harboring 49 putative open reading frames (ORFs) were found to be associated with enhanced Cd tolerance. In addition to several ORFs for ion transport/chelation and stress response, most ORFs were assumed to be associated with non-direct metal resistance mechanisms such as energy metabolism, protein/amino acid metabolism, carbohydrate/fatty acid metabolism, and signal transduction. Furthermore, 13 ORFs from five clones selected at random were cloned and subject to Cd resistance assay. Eight of these ORFs were positive for Cd resistance when expressed in Escherichia coli, among which four ORFs significantly reduced Cd accumulation and one increased Cd enrichment of the host cells. Notably, C1-ORF1, potentially encoding a histidine kinase-like adenosine triphosphatase, was the most effective Cd resistance determinant and reduced host Cd accumulation by 33.9%. These findings highlight the vast capacity of soil microbiome as a source of gene pool for bioengineering. The novel genetic determinants for Cd resistance identified in this study merit further systematic explorations into their molecular mechanisms. 相似文献
64.
A fertile hexaploid oat plant was obtained after several generations of selection for seed set and plant type from a colchicine-produced
decaploid hybrid, Avena abyssinica(2n = 4x = 28, AABB) × A. sativa (2n = 6x = 42, AACCDD). The selected line proved to be stably fertile and in many characteristics equal or superior to the
hexaploid parent. The grain protein fractions showed two qualitative differences from those of the pollen parent and several
differences from the maternal parent. The fractionating extraction used was new for oats. The fatty acid composition of grains
of the hybrid derivative was similar to that of the pollen parent, but different from that of the maternal parent. The maternal
parent (A. abyssinica) had a relatively high 16:0 fatty acid content (ca. 20.5 mol%) compared with the level of the hexaploid parent and the hybrid
derivation (ca. 17.5 mol% each) in field-grown grain. However, in grain produced in the greenhouse, the hexaploids had ca.
20.5 mol% of 16:0 fatty acid and a decrease in 18:1 fatty acid, whereas seed of the A. abyssinica parent showed only a slight increase (ca.21.5 mol%) in 16:0 fatty acid. These and other responses statistically significant
may be due to adaptation to temperature conditions being wider in the hexaploids than in the East-African A. abyssinica. A new method of grain lipid extraction was introduced and showed good reproducibility. The derived hexaploid oat can be
crossed with A. sativa for breeding purposes and due to its early maturity might also have direct use in northern or high-altitude cultivation.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
65.
The inheritance of resistance to lentil (Lens culinaris Medik.) vascular wilt caused by Fusarium oxysporum f.sp. lentis was investigated in a cross between resistant (ILL5588) and susceptible (L692–16-l(s)) lines. F2:4 progenies and F6:8, F6:9 recombinant inbred line (RIL) populations were assessed for their wilt reaction for three seasons in a well-established wilt-sick plot. Resistance to wilt was conditioned by a single dominant gene in the populations studied. The map location of the Fw locus was identified for the first time through linkage to a random amplified polymorphic DNA (RAPD) marker (OPK-15900) at 10.8 cM. Two other RAPD markers (OP-BH800 and OP-DI5500) identified by bulked segregant analysis were associated in the coupling phase with the resistance trait, and another marker (OP-C04650) was associated with repulsion. The DNA markers reported here will provide a starting point in marker-assisted selection for vascular wilt resistance in lentil. 相似文献
66.
C. Fortes Ferreira M. Gonzaga Pereira A. da Silva dos Santos R. Rodrigues R.E. Bressan-Smith A. PioViana R. Figueiredo Daher 《Euphytica》2003,134(1):43-46
Among the main causes of poor yield in common beans are fungal, viral and bacterial diseases. Common bacterial blight, caused
by Xanthomonas axonopodis pv. phaseoli (Xap), is one of the major bacterial diseases leading to significant losses in Brazil. Chemical control is ineffective, therefore,
the use of resistant varieties becomes an interesting alternative. The objective of the present work was to evaluate disease
resistance under natural infection of the pathogen in 109 recombinant inbred lines (F7) of P. vulgaris originated from the cross HAB-52 (susceptible — snapbean) × BAC-6 (resistant — common bean) in two different environments,
as well as to calculate genetic parameters to assist in the selection of promising materials to be used in the CBB resistance
breeding program. The data of the genetic parameters were
compared to those calculated for the F3 generation originated from the same cross. The heritability results for DI (disease index) and VI (variation index) in F3 were 26.85% and 0.26, respectively, whereas in F7 they were 91.77% and 1.36, respectively. These results demonstrate a potential to be explored for this advanced population,
that in the future, along with other pathogen variability studies and tests in other environments, may provide more information
regarding a more precise evaluation of promising genotypes to be used in common bean breeding programs aiming to obtain CBB
resistant varieties.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
67.
采用 RT- PCR技术 ,从传染性法氏囊病病毒 (IBDV)细胞适应株 GZ911中扩增了 A片段的 2个片段 GA5和 GA3,从中国分离的 IBDV超强毒株 L X中扩增了 B片段的 2个片段 L B5和 L B3。将 GA5和 GA3克隆到质粒p Bss K的 Eco R / Kpn 位点 ,将 L B5和 L B3克隆到 p Bss K的 Eco R / Xba 位点 ,获得携带 GZ911完整 A片段基因的质粒 GA- p Bss K和携带 L X完整 B片段基因的质粒 L B- p Bss K。然后将 GZ911的 A片段 c DNA和 L X的 B片段c DNA分别插入带有巨细胞病毒立即早期加强子 /启动子的质粒 p AL TER- MAX中 ,获得重组质粒 GA- p AL TER和L B- p AL TER。用 GA- p AL TER和 L B- p AL TER共转染鸡胚成纤维细胞 (CEF) ,获得具有感染活性的重组 IBDV,命名为 r IBDV- GZ L X。该方法的建立为在体外对 IBDV的基因组进行遗传操作 ,进而彻底了解 IBDV基因的结构与功能的关系打下了基础。 相似文献
68.
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70.
不同磷、钾处理小麦苗期氮营养性状的QTL分析 总被引:1,自引:0,他引:1