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41.
Agronomic traits of soybean cultivars released in different decades after grafting record‐yield cultivar as rootstock 下载免费PDF全文
Shengyou Li Fei Teng Demin Rao Xingdong Yao Huijun Zhang Haiying Wang Shuhong Song Steven K. St. Martin Futi Xie 《Plant Breeding》2017,136(2):133-138
Breeders have seldom considered the selection for root traits during the genetic improvement in soybean. It is hypothesized that grain yield would be increased by the root function improvement, especially for the current cultivars. The objective of this grafting experiment was to determine the effect of record‐yield cultivars L14 or Z35 as rootstocks on agronomic traits of cultivars released in different decades. A total of 11 cultivars, released in different decades, were used to graft onto L14 or Z35 rootstocks. The agronomic traits were measured in the pot‐culture experiments. Grafting cultivars released in different decades onto L14 or Z35 rootstocks resulted in higher yield, 100‐seed mass and apparent harvest index as compared with those of non‐grafted or self‐grafted plants. Grain yield gain of cultivars grafted onto record‐yield cultivar rootstocks was 0.40 g/plant/year from 1966 to 2006, which was larger than that of non‐grafts and self‐grafts (0.27 g/plant/year). The yield of current cultivars should increase more if their root functions were improved. 相似文献
42.
为了解黄芪对硒的吸收转运能力,以黄芪为试材,采用根施和叶面喷施硒2种方式,探索施用不同浓度(0、5、10、50、100μmol/L)的硒酸钠和亚硒酸钠,对黄芪生物量、硒含量以及硒在植物体内的转运能力进行研究。结果表明,无论是以硒酸钠还是亚硒酸钠作为硒源均有利于黄芪地上部和根部干物重、硒含量的增加,随着硒浓度的增加干物重呈先升高后下降的趋势,黄芪地上部硒含量呈逐渐上升的趋势,根部硒含量与之相反。添加硒酸钠和亚硒酸钠处理时,在10μmol/L浓度处理时黄芪地上部和根部干物重最大,分别比CK增加了49.89%、60.87%和23.36%、60.00%。添加相同浓度的硒酸钠处理时,黄芪地上部和根部中硒含量高于施亚硒酸钠处理,在100μmol/L浓度处理下黄芪地上部硒含量最大为119.13μg/g,在5μmol/L浓度处理下黄芪根部硒含量最大为52.25μg/g。2种施硒方式下,根部施硒酸钠更有利于黄芪对硒的富集,且黄芪根部向地上部转运硒的能力随施硒浓度的升高逐渐增大。 相似文献
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A 6‐month trial was conducted to evaluate the effects of dietary cottonseed meal (CSM) and free gossypol (FG) on allogynogenetic silver crucian carp, Carassius auratus gibelio♀ × Cyprinus carpio♂ with 4 replicates of each treatment. Isonitrogenous and isocaloric diets were formulated with the 0 g kg?1 (control), 200 g kg?1, 400 g kg?1, and 560 g kg?1 CSM. Diets with FG were made by supplementing batches of control diet with 214 mg kg?1, 428 mg kg?1, and 642 mg kg?1. Weight gain, specific growth rate, and protein efficiency ratio increased significantly up to an inclusion level of CSM of 400 g kg?1 in the diet, with a significant decrease in food conversion ratio. Further increase in CSM to 560 g kg?1 did not cause further changes in fish performance. Free gossypol did not affect fish performance significantly at any inclusion level. Neither CSM nor FG caused significant effects in any of the other evaluated parameters such as whole body composition, haemoglobin concentration, activities of serum lysozyme, superoxide dismutase, alanine aminotransferase and aspartate aminotransferase, and histology of hepatic tissues and midgut. Our results suggested that crucian carp can tolerate at least 642 mg kg?1 FG and that it is safe to including 400 g kg?1 CSM in crucian carp feed. 相似文献
45.
以中华鲟(Acipenser sinensis)脑垂体总RNA为模板,采用RT-PCR和RACE方法,获得中华鲟神经内分泌多肽(7B2)基因的3个重叠片段,测序后拼接得到986 bp全长基因序列,其中包括5'端非翻译区(5′-UTR)14 bp、3′端非翻译区(3-′UTR)261 bp和开放阅读框711 bp。翻译编码236个氨基酸。其中前43个氨基酸为7B2的信号肽。经BLAST比对发现中华鲟7B2蛋白的同源性与斑马鱼(Danio rerio)的相似性最高为82%。系统发育分析表明,中华鲟与斑马鱼亲缘关系最近。半定量RT-PCR分析表明:在脑中7B2 mRNA表达量最高,心脏、性腺、胰等组织中表达次之,肠、肾、皮肤等组织中少量表达,肝和鳃几乎不表达。 相似文献
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Toxicity of aflatoxin B1 (AFB1) was investigated in juvenile hybrid sturgeon Acipenser ruthenus ♂ × A. baeri♀, an important coldwater finfish farmed in China and other countries. Seven experimental diets (Diet A–G) containing different levels of AFB1 (0, 1, 5, 10, 20, 40 and 80 μg kg?1 diet) were fed to juvenile sturgeon weighing 10.53 ± 0.17 g kg?1 to determine its effect on survival, growth, feed consumption, hematocrit, liver histology as well as muscular and hepatic toxin accumulation. The experiment lasted for 35 days and was conducted in two periods of 25 and 10 days each. No external changes or unusual behaviour was observed in the fish fed diets with AFB1. Mortality was observed in fish fed with highest levels of AFB1 (80 μg kg?1– Diet G) from day 12 onwards. After 25 days, fish fed the diet of 80 μg AFB1 kg?1 showed significant lower survival (50 ± 5.77%) followed by those fed 40 μg AFB1 kg?1 diet (80 ± 5.77%) and 20 μg AFB1 kg?1 diet (86.66 ± 3.33%). No significant difference was observed in specific growth rate (SGR) or hepatosomatic index (HSI) between groups. Hematocrit was significantly higher in the fish fed the diet of highest AFB1. The fish were weighed at day 25 in some treatments (Diets F and G) because of high mortality. However, feeding was continued for another 10 days to observe mortality or behavioural changes if any in the other groups. After 35 days, survival in the fish fed Diet F (40 μg AFB1 kg?1) was 40% and those fed Diet E (20 μg AFB1 kg?1) was 36.2%. Significant histopathological changes including nuclear hypertrophy, hyperchromasia, extensive biliary hyperplasia, focal hepatocyte necrosis and presence of inflammatory cells were observed in the liver of fish fed high levels of aflatoxin (40 and 80 μg kg?1). AFB1 accumulation in fish muscle and liver increased with increased dietary AFB1 levels. It could be confirmed that 10 μg AFB1 kg?1 diet was the maximum allowable level in hybrid sturgeon diet. 相似文献
48.
为提高小麦1B/1R易位系的加工品质,本研究选用高分子量麦谷蛋白亚基组成为1/7+9/2+12的小麦1B/1R易位系品种科农199为母本,与高分子量麦谷蛋白亚基组成为1/7OE+8*/5+10的强筋春小麦品种津强6号杂交,利用分子标记在F4代株系中筛选到一个7OE亚基基因与黑麦碱基因聚合在同一条染色体上的1B/1R易位系材料。PCR结果显示,该聚合材料和非聚合材料在Glu-A1和Glu-D1位点没有差异。在温室种植条件下,对这些聚合材料和非聚合材料及其亲本进行麦谷蛋白溶胀指数(SIG)测定,结果表明,与1B/1R易位系亲本科农199比较,聚合5+10优质亚基后SIG值显著提高,聚合7OE优质亚基后,SIG值进一步显著提高,部分聚合材料达到了强筋亲本津强6号的水平。将聚合材料和非聚合材料及其亲本种植于大田,发现聚合5+10和7OE优质亚基株系的乳酸-SDS溶剂保持力(LA-SDS SRC)和SDS沉降值均显著高于只聚合5+10优质亚基的株系,但未达到强筋亲本... 相似文献
49.
为筛选林芝松口蘑(Tricholoma matsutake)子实体中具抗肿瘤作用的组分,采用MTT法测定林芝松口蘑乙醇提取物的不同有机溶剂萃取分部对乳腺癌细胞(MCF-7)、胃癌细胞(SGC-7901)和肺癌细胞(A549)的体外抑制率。结果表明:林芝松口蘑乙醇提取物的抑癌活性物质主要集中在氯仿分部,100μg/mL作用48h,对MCF-7和SGC-7901的抑制率分别达到了64%和55%;乙醇提取物的各萃取分部对A549抑制效果较差,在实验浓度范围内抑制率均未超过25%。 相似文献
50.
簇毛麦是小麦品种改良重要的遗传资源,其5VS上含有硬度基因Dina/Dinb、抗白粉病基因Pm55和抗条锈病基因Yr5V,创制普通小麦-簇毛麦5VS易位系新种质,对于高效利用5VS上的有益基因进行小麦品种遗传改良具有重要意义。为了便于鉴别普通小麦-簇毛麦5VS纯合易位,本研究以mInDel软件分析普通小麦中国春基因组序列,开发了小麦第5同源群短臂的InDel特异分子标记WC656,对小麦品种以及普通小麦-簇毛麦5VS.5AL和5VS.5DL易位系及其衍生后代进行PCR扩增,根据扩增片段大小来区分5AS、5BS、5DS染色体臂以及5VS易位系。结果表明,在21个普通小麦品种、小麦-簇毛麦5VS回交F2代中杂合易位单株,均扩增出379 bp(5AS)、471 bp(5BS)、422 bp(5DS)3条带。在T5VS.5AL高代品系、回交F2代中纯合易位单株扩增出471 bp(5BS)、422 bp(5DS)2条带,379 bp(5AS)条带缺失。T5VS.5DL高代品系、回交F2代中纯合易位单株扩增出379 bp(5AS)、471 bp(5BS)2条带,422 bp(5DS)条带缺失。WC656鉴别的5VS纯合易位结果与顺序FISH-GISH分析结果一致。T5VS.5AL、T5VS.5DL具有抗白粉病、籽粒硬度指数低等优良特性。因此,利用InDel分子标记WC656可以鉴别普通小麦-簇毛麦T5VS.5AL、T5VS.5DL衍生后代中的纯合易位,PCR扩增实验操作相对简便,可以为分子标记辅助选育携有5VS纯合易位的软质弱筋小麦提供帮助。 相似文献