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21.
目的 构建一套基于水稻重要性状基因标记的品种DNA指纹鉴定体系,为加强主栽优良食味半糯粳稻品种的种质管理与品种保护奠定基础。方法 以34个江浙沪主栽优良食味半糯粳稻品种为供试材料,通过已知标记多态性鉴定、公共数据库基因序列比对、基因组重测序等多种方法对水稻重要性状调控基因的关键差异位点进行筛选,开发核心SNP或InDel标记;利用As-PCR技术将SNP标记发展为依据电泳条带鉴别的简单PCR标记,通过电泳条带特征化和类型分析获得基因型信息,构建半糯粳稻品种的DNA指纹图谱库。结果 筛选出来源于40个水稻重要性状调控基因的54个核心标记,包括18个SNP标记和36个InDel标记;54个标记在20个品种中共检测到155个有效特征化条带,转化为155个0/1数据位点,建立各品种的DNA指纹数据库,可区分全部供试品种。遗传多样性分析表明,品种间遗传相似性变异范围为0.47—0.90,其中,南粳7718与苏香粳100的相似性系数最小,而南粳9308与南粳9036的相似性系数最大,二者存在8个数据位点差异。亲缘关系分析可将供试品种划分为6个分支,其中,南粳7718为独立分支,表明其与其他品种间的亲缘关系较远。核心标记鉴定效果的进一步验证表明,该套标记可以对14个半糯粳稻新品种进行有效区分,聚类图显示其分布于Ⅱ、Ⅲ和Ⅳ 3个类群,证实各品种间基因型信息的差异性;并利用该套标记鉴定了一个未知半糯水稻的品种真实性,根据基因型和聚类分析,将其判定为南粳9108。结论 经优化筛选,获得可准确区分当前主推半糯粳稻品种的54个核心标记,并发展为可电泳检测的简单PCR标记,利用该套标记组合构建了34个江浙沪地区主栽优良食味半糯粳稻品种的DNA指纹图谱。  相似文献   
22.
采用加标回收方法检测分析氯氰菊酯、联苯菊酯、溴氰菊酯、氰戊菊酯、腐霉利、抗蚜威、三唑磷、氯唑磷、甲拌磷、乐果10种农药对韭菜、芹菜残留检测结果的样品浓度与回收率分布关系,显示加标回收率在10%~200%.应用基质匹配法、内标法质控处理,校准调控后的加标回收率在韭菜中为93.2%~103.7%,RSD为1.6%~7.7%;芹菜中为87.2%~100.3%,RSD为2.1%~9.6%.对照《实验室质量控制规范食品理化检测附录F》(GB/T 27404—2008),检测结果符合技术要求.  相似文献   
23.
【目的】研究膜下滴灌水稻不同水分处理对耗水特征和水分生产效率的影响。【方法】2017年设置5个灌溉定额,对比分析不同水分处理下水稻产量、各生育期耗水量。【结果】W5处理(灌溉定额910.00 mm)的水稻产量比其他处理分别增加21.95%~458.43%。膜下滴灌水稻全生育期5个水分处理的耗水强度分别为3.75~7.14 mm/d。随着灌水量减少叶面积衰减指数逐渐增大,叶片表现出早衰特征,株高受到灌水量抑制。W5处理与其他处理水分生产率相比分别提高7.61%~193.06%。生育阶段耗水强度变化规律为拔节孕穗期>抽穗扬花期>灌浆期>分蘖期>成熟期>苗期。【结论】水稻全生育期适宜灌溉定额910.00 mm,在拔节孕穗期、分蘖期2个关键需水期,满足水稻水分需求。  相似文献   
24.
1. An experiment was conducted to determine the individual and combined effects of two essential oils, oregano and garlic, on carcass characteristics, meat composition, colour, pH and sensory quality of broiler meat.

2. The diets were supplemented with no essential oil (control), oregano essential oil or garlic essential oil at 300 mg/kg and oregano essential oil at 150 mg/kg + garlic essential oil at 150 mg/kg.

3. Dietary oregano and garlic oil supplementation did not affect carcass yields, the relative weight of carcass parts, breast and thigh meat composition, pH or b* value of breast meat. Oregano + garlic oil supplementation significantly decreased the L* value. The a* value of breast meat in birds given a diet supplemented with oregano oil was lower than that in birds given a diet supplemented with garlic oil and oregano oil + garlic oil. The essential oil addition had no positive effect on the oxidative stability. There was no difference between the treatments in breast appearance.

4. The juiciness, flavour, oxidised flavour and acceptability of breast meat samples were affected by treatments.  相似文献   

25.
In this work, trace metals such as Hg, Pb, As, Cd, Cu, Fe, Mn and Zn in underground water samples obtained from three wells, an ash-pond and drinking water located near the Yatagan Thermal Power Plant were measured. As, Hg, Cu and Zn contents of the underground water were lower than those reported in the EEC (European Economic Community) and WHO (World Health Organization) guidelines. In contrast, the levels of Fe, Pb, Cd and Mn in some groundwater samples were higher than EEC and WHO guideline values. The trace metal concentrations in coal ash-pond water were observed to be lower than water quality standards with the exception of Pb. The obtained results indicated that the trace metal concentration in the sampled drinking water site did not exceed WHO limits.  相似文献   
26.
Combined effects of organic or inorganic pollutants on soil microbial activities were investigated in field plots grown with four types of covering plants. It was derived from this study that combined effects were dependent not only on the type and dose of pollutants, addition of soda lime, plant type and season variation, but also on test parameters. When jointly added, higher doses of Cd, Cu, Pb, Zn and As caused significant inhibition. Addition of soda lime could even enhance inhibition. Joint effects of phenanthrene, MET (active ingredient: paclobutrazol) and 1,2,4-trichlorobenzene were not significant, and may be covered by other biotic or abiotic factors. Compared with other two parameters (respiration and microbial biomass), dehydrogenase activity appeared to be more sensitive for evaluating the toxicity of anthropogenic pollutants in soil. Soil samples collected in summer often had higher microbial activities than those in fall. The microbial activity in soil decreased with covering vegetation in the order alfalfa > pine > poplar and maize, albeit some exceptions were observed.  相似文献   
27.
28.
Coagulase-negative staphylococci (CNS) are the most prevalent mastitis pathogens. However, virulence characteristics of CNS have not been well determined. The presence of genes for enterotoxins (sea-sej), toxic shock syndrome toxin-1 (tst), the exfoliative toxins (eta, etb), Panton–Valentine leukocidin (pvl) and mecA of CNS species isolated from cows and ewes with subclinical mastitis was investigated in this study. A total of 121 CNS (81 cows, 40 ewes) representing 18 different Staphylococci species were examined by PCR, and 38.1% (33 cows and 13 ewes) of CNS isolates had one or more se genes. The difference between percentages for SE toxin genes of CNS strains isolated from cows (40.7%) and ewes (32.5%) was not statistically significant (P > 0.05; χ 2 = 0.380). It was found that S. simulans isolates had the highest prevalent se genes. Furthermore, the most common SE gene types was seh-sej. In this study, none of the isolates harbored the toxic shock syndrome toxin gene (tsst) and the exfoliative toxin genes (eta, etb). Five cow (6.17%) and three ewe CNS (7.5%) isolates had mecA gene. Three cow (3.7%) and two ewe CNS (5.0%) isolates had pvl gene. In conclusion, the present study showed that CNS species isolated from cows and ewes could serve as potential reservoir of se, mecA, and pvl genes.  相似文献   
29.
The aim of the present study was to clarify the relation between salsolinol (SAL)‐induced prolactin (PRL) release and photoperiod in goats. A single intravenous (i.v.) injection of SAL was given to adult female goats under short (8 h light, 16 h dark) or long (16 h light, 8 h dark) photoperiod conditions at two different ambient temperatures (20°C or 5°C), and the PRL‐releasing response to SAL was compared to that of thyrotropin‐releasing hormone (TRH) or a dopamine (DA) receptor antagonist, sulpiride. SAL, as well as TRH or sulpiride, stimulated the release of PRL promptly after each injection in both 8‐ and 16‐h daily photoperiods at 20°C (P < 0.05). The area under the response curve (AUC) of PRL for the 60‐min period after injections of saline (controls), SAL, TRH and sulpiride in the 16‐h daily photoperiod group was greater than each corresponding value in the 8‐h daily photoperiod group (P < 0.05). There were no significant differences in the AUC of PRL among the values produced after the injection of SAL, TRH and sulpiride in 16‐h daily photoperiod group; however, the values produced after the injection of TRH were smallest among the three in the 8‐h daily photoperiod group (P < 0.05). The PRL‐releasing responses to SAL, TRH and sulpiride under a short and long photoperiod condition at 5°C resembled those at 20°C. These results show that a long photoperiod highly enhances the PRL‐releasing response to SAL as well as TRH or sulpiride in either medium or low ambient temperature in goats.  相似文献   
30.
我国畜禽饲料资源中微量元素铜含量分布的调查   总被引:1,自引:1,他引:0  
目的 研究我国不同地区间各种饲料原料中铜含量分布情况,以及我国畜禽基础饲粮中铜水平,从而为饲粮中合理添补铜提供依据。方法 对采自全国31个省、直辖市和自治区的7大类(谷物籽实、谷物籽实加工副产品、植物性蛋白饲料、动物性蛋白饲料、牧草类、秸秆类和矿物质饲料)37种饲料原料共3 903个饲料样品,经预处理后用MARS6高通量密闭微波消解系统进行微波消解,然后用IRIS Intrepid II等离子体发射光谱仪测定其铜含量。用国家标准物质猪肝粉或黄豆粉作为参照标准,以保证测定结果的可靠性。结果 饲料原料中铜含量测定结果表明:谷物籽实(包括玉米、小麦、稻谷和大麦)平均铜含量为3.95 mg·kg -1(范围为2.50—5.34 mg·kg -1);谷物籽实加工副产品(包括玉米蛋白粉、玉米DDGS、玉米胚芽粕、次粉、小麦麸、小麦DDGS、碎米和米糠)平均铜含量为7.16 mg·kg -1(范围为1.62—12.13 mg·kg -1);植物性蛋白饲料(包括膨化大豆、大豆粕、菜籽粕、棉籽粕、花生粕、亚麻粕和葵花粕)平均铜含量为16.37 mg·kg -1(范围为6.45—30.40 mg·kg -1);动物性蛋白饲料(包括鱼粉、肉粉、水解羽毛粉、肠膜蛋白粉、血浆蛋白粉和血球蛋白粉)平均铜含量为11.14 mg·kg -1(范围为1.90—20.04 mg·kg -1);牧草类(包括羊草、黑麦草、苜蓿和青贮玉米)平均铜含量为7.85 mg·kg -1(范围为4.31—9.92 mg·kg -1);秸秆类(包括玉米秸秆、小麦秸秆、稻秸和甘薯藤)平均铜含量为7.50 mg·kg -1(范围为3.38—13.89 mg·kg -1);矿物质饲料(包括石粉、磷酸氢钙、骨粉和贝壳粉)平均铜含量为6.79 mg·kg -1(范围为3.39—11.45 mg·kg -1)。这37种饲料原料的平均铜含量范围为1.62—30.40 mg·kg -1,而各类饲料原料铜含量分布规律是:植物性蛋白饲料(16.37 mg·kg -1)>动物性蛋白饲料(11.14 mg·kg -1)>牧草类饲料(7.85 mg·kg -1)>秸秆类饲料(7.50 mg·kg -1)>谷物籽实加工副产品(7.16 mg·kg -1)>矿物质饲料(6.79 mg·kg -1)>谷物籽实(3.95 mg·kg -1)。以省(区)为单位比较,发现不同地区间的玉米、小麦和大豆粕的铜含量差异显著(P<0.05)。四川省玉米和大豆粕铜含量最高(分别为2.97和15.74 mg·kg -1),内蒙古自治区最低(分别为1.66和11.72 mg·kg -1);甘肃省小麦铜含量最高(5.61 mg·kg -1),河北省最低(4.02 mg·kg -1)。根据全国各地猪、鸡常用的152个饲料配方计算出基础饲粮中可提供的铜含量为5.07—6.54 mg·kg -1,如根据我国及美国NRC猪、鸡饲养标准中铜营养需要量的要求,基础饲粮中的铜含量基本可提供猪的铜营养需要,可提供鸡大部分铜的营养需要,但上述估算尚未考虑不同饲料原料中铜的利用率。结论 我国不同种类和不同地区饲料原料中铜含量差异较大,全国猪、鸡常用基础饲粮配方中铜含量可提供猪、鸡大部分的铜营养需要量。因此,建议在配制饲粮时,应充分考虑不同地区基础饲粮中的铜含量及其利用率,精准配制饲粮,以满足畜禽高效生产需要,同时减少铜的添加和排放对环境的污染。  相似文献   
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