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61.
棉花雄性不育系网室蜜蜂授粉技术研究   总被引:2,自引:0,他引:2  
旨在研究蜜蜂在棉花不育系上的传粉特征以及是否适宜棉花三系制种。本试验在网室内利用蜜蜂(Apis mellifera Ligustica Spinola)进行棉花不育系授粉,以人工授粉为对照,调查晴天与阴天蜜蜂在棉花保持系和不育系花朵上的造访频率和单花停留时间,并比较蜜蜂和人工授粉田间农艺性状、制种产量及成本。结果表明,晴天条件下,蜜蜂在棉花保持系的造访频率为60 次/h,不育系为49.2 次/h,差异达显著;阴天条件下,蜜蜂在保持系的造访频率为23.4 次/h,不育系为13.8 次/h,差异不显著。蜜蜂授粉和人工授粉单铃籽粒数有显著差异,而单株铃数和空果枝数差异达极显著,果枝数、铃重、衣分、子指、发芽率则无显著差异。蜜蜂授粉种子产量可达人工授粉的70%左右,但其制种成本远低于人工授粉,可节约费用三分之二。因此,合理利用蜜蜂授粉技术对棉花不育系制种具有重要的推动作用。  相似文献   
62.
In poultry processing plants, fecal material and ingesta are the primary source of carcass contamination with microbial pathogens. The current practice of the poultry inspection in the United States is primarily human visual observations. Since the visual inspection is becoming more challenging in poultry processing plants adopting high-speed lines, a rapid sorting system could significantly improve the detection and monitoring of carcasses with surface fecal material and ingesta. As a result, we developed a prototype line-scan hyperspectral imaging system configured as a real-time multispectral imaging subsystem for online detection of surface fecal material and ingesta. Specifically, we integrated a commercially available off-the-shelf hyperspectral image camera into the system with two line lights and a custom software program for real-time multispectral imaging. The bottleneck of the imaging system was the data acquisition. For that reason, a multithreaded software architecture was designed and implemented not only to meet the application requirements such as speed and detection accuracy, but also to be customizable to different imaging applications such as systemic disease detection in the future. The image acquisition and processing speed tests confirmed the system could operate to scan poultry carcasses in commercial poultry processing plants. The fecal detection algorithm was based on the previous research using different hyperspectral imaging systems. A new carcass detection and image formation algorithm was developed to allow existing image processing and detection algorithms reusable without any modifications. Sixteen chicken carcasses and four different types of fecal and ingesta samples were used in a study to test the imaging system at two different speeds (140 birds per minute and 180 birds per minute) in a pilot-scale poultry processing facility. The study found that the system could grab and process three waveband images of carcasses moving up to 180 birds per minute (a line-scan rate 286 Hz) and detect fecal material and ingesta on their surfaces. The detection accuracy of the system varied between 89% and 98% with minimum false positive errors (less than 1%), depending on tested detection algorithms. Therefore, these findings provide the basis of not only a commercially viable imaging platform for fecal detection but also a single poultry inspection system for multiple tasks such as systemic disease detection and quality sorting.  相似文献   
63.
利用高效液相色谱技术对不同品系玉竹的化学成分进行研究,建立玉竹药材指纹图谱。色谱柱为ZORBAXEclipseXDB—C18(250mm×4.6mm,5μm);流动相A为O.05%甲酸一乙腈,B为0.05%甲酸水溶液,梯度洗脱。体积流量1.0mL/min;检测波K210nm。试验结果显示,各品系玉竹化学组成稳定,品系内植株间相似度在0.9以上;2个玉竹品系化学组成类似,品系间平均相似度0.794。高效液相色谱指纹图谱可以用于玉竹品系鉴定与质量控制。  相似文献   
64.
山东省地方畜禽品种资源的保护与利用研究   总被引:2,自引:1,他引:1  
山东省地方畜禽品种资源丰富。有地方畜禽品种32个,已对烟台黑猪、莱芜黑猪等5个猪种、鲁西黄牛、德州驴、小尾寒羊、洼地绵羊、黑耳兔等19个畜种资源按照标准进行了主产地、分布区域、群体规模的描述。采集耳组织、血细胞样本800余个,并对这些样本进行了DNA提取和基因组学的分析,初步建立了山东地方家畜遗传资源库。利用地方良种历经10余年已经培育出了鲁烟白猪新品种和鲁农Ⅰ号猪配套系。  相似文献   
65.
【目的】实现基于简化物理模型方法的碳卫星叶绿素荧光反演,并将反演结果与OCO-2荧光产品进行对比。【方法】文章选取770.1 nm处受大气影响较小的KI夫琅和费暗线,利用碳卫星的L1B级星下点观测数据和对日定标数据,以中国东北为研究区,利用基于简化物理模型的荧光提取算法,反演得到中国东北地区2018年7月的叶绿素荧光信息,并利用同期MODIS数据的云掩膜产品来剔除受云影响的区域,得到晴空条件下的荧光结果。【结果】该研究反演得到的东北地区2018年7月荧光结果值介于-3~7 mW/m~2/sr/nm之间,荧光强度较大的点分布在锡林郭勒盟中西部,辽宁省的中部和东部,吉林省的西南部以及黑龙江的西部地区。【结论】将该文反演结果与OCO-2卫星的荧光产品进行对比,发现两者之间具有很好的一致性,说明基于简化物理模型的反演算法可以较好地实现碳卫星的叶绿素荧光反演。  相似文献   
66.
为了揭示安徽省玉米种植密度现状,提出适合安徽不同种植习惯的密度调控对策,为安徽省玉米单产的提高提供科学依据。笔者连续2 年对安徽省玉米产区7 市24 县区进行密度取样调查,分析其株距、行距等密度构成因子。结果表明:安徽省玉米种植平均行距0.55 m,平均株距0.32 m,平均种植密度66870 株/hm2,总体合理,但区域分布不均,主要分为6 个种植习惯区,针对这6 个种植习惯区提出了适度增密,推广耐密品种,调整种植行距,推广玉米播种机械等4条对策。  相似文献   
67.
为选育制备弱毒疫苗所需的毒害艾美耳球虫(Eimeria.necatrix)早熟株,以临床表现、平均增重、相对增重率、小肠病变记分、血便记分、死亡率、每克粪便中的卵囊数(OPG)、卵囊总产量和每个卵囊的繁殖能力为指标,研究了E.necatrix早熟株与亲本株的致病性和繁殖力。结果表明该早熟株与其亲本株相比,早熟株的致病性降低了,接种相同剂量时早熟株平均增重、相对增重率高于亲本株,病变记分、血便记分和死亡率均低于亲本株;早熟株产卵高峰提前,繁殖力下降至亲本株的55%左右,符合球虫早熟疫苗株的特性。  相似文献   
68.
Downed coarse woody debris (DCWD) plays an important role in ecosystem processes and should be considered in land management decisions. Unfortunately accurate quantification of its abundance is difficult, due to its patchy distribution. This is especially problematic in woodland ecosystems where DCWD is relatively scarce, unevenly distributed and smaller in size than in other forest types. This study compared the efficacy of the line intersect and strip plot methods to sample properties of DCWD at woodland sites with differing fire histories. Although measures of abundance using the two methods did not differ statistically, the line intersect method had 20% less variability in the data, was quicker to perform and made it easier to locate individual pieces of DCWD than the strip plot method. The results of this study indicate that transects of 100 m or less are insufficient for estimating DCWD volume in woodlands. An acceptable level of precision was reached at approximately 450 m at very recently burnt sites and 700 m at long unburnt sites when only transect length was considered. However when taking both transect length and number of replicates into account, an acceptable level of precision was reached at 500 m when sampling a minimum of 20 sites. It is therefore recommended that pilot studies should be conducted to determine appropriate sampling intensities in previously unsampled areas as DCWD volume estimates are sensitive to the rate at which variance changes with increasing transect length. This is particularly important when there is variation in the disturbance history of the sites. However, if it is not possible to conduct pilot studies, the requirement would be to sample line intersect transects of at least 500 m, at a minimum of 20 sites in woodland systems.  相似文献   
69.
为了扩增优质蛋白玉米育种新种质,用普通玉米种质转育创制优质蛋白玉米(QPM)近等基因系;利用SSR标记phi057进行辅助选择,以优质蛋白玉米种质为o2基因供体,转导、构建来自不同遗传背景普通玉米种质为受体的QPM近等基因系。结果表明:利用共显性SSR标记引物phi057在o2基因供体自交系与普通玉米受体自交系间表现多态性,能区分O2O2、O2o2和o2o2等3种基因型,来自不同遗传背景种质所构建获得的QPM近等基因系赖氨酸含量有不同程度提高,赖氨酸含量达到0.36%~0.42%,不同遗传背景受体自交系赖氨酸增加幅度9.1%~64.0%。普通玉米种质导入供体o2基因后能够提高种质赖氨酸含量。  相似文献   
70.
孙健 《北方水稻》2008,38(3):110-112
试验采用大区对比的方法,研究垦鉴稻14等17个品种(品系)在应用水稻"三化"栽培模式下的生物学特性和经济性状,旨在筛选出适合黑龙江省第三积温带下限区域的优良水稻品种。结果表明:垦粳04-549、垦鉴稻14、垦稻11、农大04-004等几个品种(系),在抗性、丰产性等方面表现较好。  相似文献   
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