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941.
Cotton yield improvement is vital to fulfill rising global demands. The identification of major quantitative trait loci (QTL) for yield components was helpful in molecular marker-assisted selection (MAS) to improve cotton yield. We previously identified a densely populated QTL region for fiber qualities and yield components on chromosome D8 (Chro.D8) of Upland cotton from a (7235 × TM-1)RIL. In the present study, to fine-map yield component QTLs, we chose three overlapped recombinant inbred lines (RILs) with different intervals included the yield component QTLs, and backcrossed each line with TM-1 to develop three large sized mapping populations. Phenotypic data for yield components were collected in Nanjing (JES/NAU) and Xinjiang (BES/XJ) in 2006 and 2007. Three simple sequence repeat (SSR) genetic linkage maps on chro.D8 were constructed using 907 individuals in (7TR-133 × TM-1)F2 (Pop A), 670 in (7TR-132 × TM-1)F2 (Pop B), and 940 in (7TR-214 × TM-1)F2 (Pop C). Three stable QTLs for boll size, two for lint percentage and one for boll number per plant,were detected on chro.D8 following analysis of three RIL backcrossed F2/F2:3 progeny at JES/NAU and BES/XJ although their cultivation practices differ greatly between these two cotton-growing regions. One QTL for boll number per plant exhibited a phenotypic variance (PV) of 5.6–10.1%, three QTLs for boll size exhibited 15.0–35.5% PV and two lint percentage QTLs exhibited 10.9–19.3% PV. Negative correlation between lint yield and fiber strength was confirmed.  相似文献   
942.
943.
普洱市烤烟评吸质量特性及其区域差异研究   总被引:5,自引:1,他引:4  
为系统、深入地了解云南省普洱烟区烤烟感官品质特点,通过对普洱市不同区域烤烟评吸质量的综合评价和统计学分析,结果得出:下部叶的香气量、浓度、劲头、余味、燃烧性、灰色和中部叶的香气质、香气量、杂气、劲头、刺激性、燃烧性、灰色和上部叶的香气量、劲头、刺激性、余味、燃烧性、灰色表现较为一致,是共性较强的普洱烟叶感官特征。墨江县鱼塘乡烤烟评吸质量最优,上、中、下部位的各项评吸指标均位居前列,其次为宁洱县勐先乡和镇沅县九甲乡。  相似文献   
944.
研究了芦荟凝胶在制汁过程及芦荟饮料在加工过程中温度和时间等因数对芦荟饮料色泽的影响。结果表明,搅汁时间10min,杀菌温度85℃,杀菌时间25min是有效控制芦荟饮料褐变的最佳工艺参数。  相似文献   
945.
斑茅(Erianthus arundinaceus Retz)是甘蔗的近缘属植物,具有多种优良特性,是甘蔗育种的重要种质资源之一。本实验使用基因组原位杂交(GISH)技术分析了甘蔗-斑茅杂种及回交后代F1、BC1和BC2的染色体构成与传递行为。结果表明:在F1代,来自斑茅HN92-77的染色体数目介于28~30条,来自热带种Badila的染色体数目介于38~40条,体细胞染色体数为2n=68~70,基本符合n+n的染色体传递方式;在BC1和BC2代,来自斑茅的染色体数分别为22~28条和13~15条,来自甘蔗的染色体数分别是87~94条和98~101条,其体细胞染色体数2n分别为110~121条和112~115条,基本上分别符合2n+n和n+n的染色体传递方式。在所观察的渐渗系中,均存在有染色体丢失的现象,但未观察到染色体发生交换与重组。  相似文献   
946.
We report that alkali ions (sodium or potassium) added in small amounts activate platinum adsorbed on alumina or silica for the low-temperature water-gas shift (WGS) reaction (H(2)O + CO → H(2) + CO(2)) used for producing H(2). The alkali ion-associated surface OH groups are activated by CO at low temperatures (~100°C) in the presence of atomically dispersed platinum. Both experimental evidence and density functional theory calculations suggest that a partially oxidized Pt-alkali-O(x)(OH)(y) species is the active site for the low-temperature Pt-catalyzed WGS reaction. These findings are useful for the design of highly active and stable WGS catalysts that contain only trace amounts of a precious metal without the need for a reducible oxide support such as ceria.  相似文献   
947.
Experiments were conducted to determine the effects of feeding different starch sources on piglets. Four diets were formulated with maize, brown rice, sticky rice and Hi‐Maize 1043 as starch sources, with resistant starch (RS) contents of 2.3%, 0.9%, 0.0%, 20.6%, and amylose and amylopectin ratio of 0.23%, 0.21%, 0.18%, 0.06% respectively. Fifty‐six pigs weaned at 28 days of age were randomly assigned to one of the four diets. In Exp. 1, six piglets in each group were fitted with an indwelling jugular catheter. After 25 days of feeding trial, venous blood samples were obtained at time zero and every 1 h for 4 h. In Exp. 2, the remaining piglets were used to determine the effects of different starch sources on the fractional synthesis rate (FSR). The results indicated that feeding the Hi‐Maize 1043 diet decreased (p < 0.05) plasma contents of glucose, insulin, lactic acid and T3, while sticky rice increased plasma contents of glucose and insulin. The insulin contents in piglets fed the sticky rice diet was 69.2 μIU/ml at 1 h post‐feeding which was highest among the starch diets. The FSR in the pancreas, spleen, duodenum, jejunum, ileum and colon in the corn group were much higher (p < 0.05) than that in the sticky rice group. These results suggest that RS is potentially beneficial for improving insulin sensitivity in young pigs and that the ratio of amylose and amylopectin have significantly effects on the FSR in splanchnic tissues in weaned piglets. Another finding of this study indicated maize with a ratio of amylose and amylopectin of 0.23 has the best starch sources for pig production.  相似文献   
948.
This research was undertaken to identify and understand the regular distribution pattern for Salmonella Enteritidis (S. enteritidis) in the internal organs of chicken after oral challenge over a 3 wk period. We used a real-time, fluorescence-based quantitative polymerase chain reaction (FQ-PCR) to detect genomic DNA of S. enteritidis in the blood and the internal organs, including heart, liver, spleen, kidney, pancreas, and gallbladder, from chicken after oral challenge at different time points. The results showed that the spleen was positive at 12 h post inoculation (PI), and the blood was at 14 h PI. The organism was detected in the liver and heart at 16 h PI, pancrea was positive at 20 h PI, and the final organ to show a positive results were the kidney and gallbladder at 22 h PI. The copy number of S. enteritidis DNA in each tissue reached a peak at 24 h–36 h PI, with the liver and spleen containing high concentrations of S. enteritidis, whereas the blood, heart, kidney, pancreas, and gallbladder had low concentrations. S. enteritidis populations began to decrease and were not detectable at 3 d PI, but were still present up to 12 d PI in the gallbladder, 2 wk for the liver, and 3 wk for the spleen without causing apparent symptoms. The results showed that the liver and spleen may be the primary sites for S. enteritidis setting itself up as a commensa over a long time after oral challenge. Interestingly, it may be the first time reported that the gallbladder is a site of carriage for S. enteritidis over a 12 d period. This study will help to understand the mechanisms of action of S. enteritidis infection in vivo.  相似文献   
949.
随着集约化养殖的不断发展。畜禽所患疾病的种类在增加,药物的耐药性和副作用不断产生,从而导致许多药物的疗效降低。中药是几千年来中国人民与疾病斗争的结晶,而且无毒副作用、无残留、不产生耐药性,对疾病的预防和治疗均有较好的效果。中药传统剂型对动物使用不方便,而中药单方对防治疾病有一定的局限性。所以,本次试验选择益母草散做成复方针剂,日的是探索中药针剂的制备方法。试验结果证明:“益母草散”的针剂制备对以后复方中药针剂的开发和研究提供了依据。  相似文献   
950.
广西雅长兰科植物分布区土壤理化性质   总被引:3,自引:0,他引:3  
为了更好地繁殖和保存兰科植物的优良基因,在广西雅长兰科植物自然保护区,按兰科植物的水平分布及垂直分布状况,选择代表性的地段设置样地22个,分别取样测定土壤(0~20 cm)理化性质。结果表明,土壤密度为0.530~1.012 g.cm-3,平均值为0.794 g.cm-3;土壤总孔隙度为39.7%~62.9%,平均值为54.1%;土壤通气度为16.7%~34.4%,平均值为25.1%。土壤pH值为5.33~8.03;有机质质量分数为30.55~98.32 g.kg-1;全氮及水解氮质量分数分别为1.46~7.38 g.kg-1和191.40~713.40 mg.kg-1;全磷及有效磷质量分数分别为0.72~1.77 g.kg-1和0.80~6.30 mg.kg-1;全钾及速效钾质量分数分别为1.32~9.88 g.kg-1和25.30~99.80 mg.kg-1。从而充分表明,广西雅长兰科植物分布区土壤较疏松、通气性及透气性能良好。土壤中氮、磷、钾主要养分质量分数丰富。  相似文献   
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