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991.
德西黄三元杂交幼牛产肉性能研究   总被引:4,自引:2,他引:2  
本文对甘肃省武威市凉州区新华乡的6头德西黄三元杂交牛11-12月龄育肥牛的产肉性能进行测定。其结果:育肥期末体重、日增重、屠宰率、净肉率、胴体产肉率、肉骨比、眼肌面积分别是322.67kg、1101.85g、55.33%、45.09%、81.47%、5.09、75.9cm^2。表明该三元杂交组合的肉用性能良好,比二元杂交的西黄有明显提高。  相似文献   
992.
泽泻田莲纹夜蛾的诱集试验及田间药效试验初报   总被引:2,自引:2,他引:0  
开展莲子与泽泻按1∶9比例面积间栽的诱集试验,结果表明:莲子对莲纹夜蛾具有较强的诱集作用,且以太空莲36号品种诱集效果最好,其泽泻田间莲纹夜蛾的种群数量明显轻于对照。田间药效试验结果显示:15%安打SC、10%除尽SC这2种化学农药和2.5%菜喜SC、20%米满SC这2种生物农药对莲纹夜蛾幼虫都具有较高防效;99%绿颖OL作为一种对害虫无抗性风险的农药,是今后莲纹夜蛾综合治理的理想药剂。  相似文献   
993.
TLC法测定虎杖中白藜芦醇的含量   总被引:5,自引:0,他引:5  
本文建立了虎杖白藜芦醇含量测定的薄层扫描分析方法:以硅胶G为薄层吸附荆,氯仿:丙酮:乙酸:水(4:4:0.5:0.2)为展开剂,在紫外灯(365nm)下观察荧光斑点,在365n/n处并进行扫描测定,线性方程为:Y=(13.826S’10^-6)-0.8698(Y为白藜芦醇浓度ug/ml,S为峰面积)。并对虎杖茎、根、叶进行了含量测定。结果表明:用TIC法测定虎杖中白藜芦醇含量方法简便、快捷、准确度高、重复性好。虎杖鲜根茎中含量达0.548%。  相似文献   
994.
应用核酸斑点杂交法检测鹅细小病毒(GPV)   总被引:5,自引:0,他引:5  
利用鹅细小病毒 (GPV)核酸探针 ,设计并建立了核酸斑点杂交法 ,用以检测 GPV核酸。该方法特异性与敏感性均较好 ,其敏感度可达 3pg。应用该方法对 4例病变典型的小鹅瘟患鹅组织器官进行检测 ,结果表明 ,患鹅脏器中 ,小肠、心、肝、胰、脾组织含毒量较高 ,其中小肠组织含毒量最高 ,而脑组织中含毒量较低。应用琼脂扩散试验验证了核酸斑点杂交法的检测结果。  相似文献   
995.
以之豇28-2为对照,对8个新选豇豆品系的早熟性、农艺性状、抗病性和产量进行了试验比较,试验结果表明,品系2-13-8和5-10-7熟性较早,后期翻花能力强,采收期长,荚长、荚粗和单荚质量有较大优势,田间对枯萎病、疫病、病毒病等表现出较强抗性,前期产量和总产量高,667 m2产量分别达3206.05、3294.98 kg/667 m2,与对照差异分别达显著和极显著水平,因此,2-13-8和5-10-7可作为长沙地区的优良早熟豇豆新品系进行深入研究。  相似文献   
996.
Summary The weighted least squares (WLS) procedure has been widely used in the analysis of generation means in biometrical genetics. Two methods to carry out the analysis have been presented in the literature (Mather & Jinks, 1971; Rowe & Alexander, 1980). Neither method identified the factors that need to be taken into account when deciding which procedure to use. This paper examines the fitting of the additive-dominance model using the general principles of least squares analysis and presents the statistical basis of each procedure. Mather & Jink's method, which is more realistic according to genetic theory, is based on the assumption that the populations have nonhomogeneous variances. Rowe & Alexander's method is based on the assumption that the populations have homogeneous variances. In the latter case, there is actually no need to do a WLS analysis. The ordinary least square analysis using the original observations rather than the means, will produce the regression parameter estimates.  相似文献   
997.
Summary Gelprotein or SDS-insoluble gel-forming glutenin was isolated from wheat flour by extraction with an aqueous 1.5% SDS solution. Remarkable intervarietal differences were observed both in amount and subunit composition of these proteins.The amount of gelprotein and the SDS-sedimentation volume both proved to be good parameters for the bread-making quality of wheat cultivars. A high correlation was observed between amount of gelprotein and SDS-sedimentation volume. The amount of gelprotein was therefore tentatively assumed to be the essential basis of the SDS-sedimentation test.The subunit composition of the gelprotein was studied by SDS-PAGE after reduction of SS bonds by mercaptoethanol. It was found that the average bread-making quality of wheat cultivars and progeny of the cross Atlas 66 x Atys which possessed subunits 3 and 10, coded for by chromosome 1D, was significantly higher than that of wheat samples possessing subunit 2 and 11, their allelic counterparts.  相似文献   
998.
Summary The segregation and linkage between glufosinate (transgenes ‘Rf3’ and ‘T177’) and blackleg resistance genes in canola (Brassica napus L.) were assessed using F1 microspore-derived doubled haploid (DH) populations from four crosses including reciprocals, two involving the transgene ‘Rf3’ and the other two involving the transgene ‘T177’. To relax the assumption of no segregation distortion required for the conventional analysis of segregation and linkage, we employed Bailey's analysis that allows detecting segregation distortion at linked loci. The significant departures from the 1:1 segregation were detected in the crosses involving the transgene ‘T177’ but not in the crosses involving the transgene ‘Rf3’. The apparent deficit of the herbicide tolerant DH lines in the crosses with the transgene ‘T177’ is likely due to differential selection against the gametes carrying ‘T177’ during microspore culture. The linkage was strong between blackleg resistance and the transgene ‘Rf3’ but weak or absent between blackleg resistance and the transgene ‘T177’, suggesting that the two transgenes are probably inserted into distant regions of the genome. The observed linkage offers an opportunity to develop new canola cultivars with both glufosinate tolerance conferred by transgene ‘Rf3’ and blackleg resistance.  相似文献   
999.
材料和方法 1.1试验材料   荔枝果实采自武鸣县府城镇大同村陶蓬德果场,品种为新丰黑叶,果实成熟度为 9成半;龙眼果实采自武鸣县城东镇大同村蒙桂辅果场,品种为石硖、储良,果实成熟度分别为 8成半和 8成。 1.2采前处理   荔枝采收前即 2000年 6月 15日和 6月 28日分别  相似文献   
1000.
Homozygous lines from six Syrian and two Jordanian landrace populations were tested under highly productive growing conditions in Tel Hadia (1982/83), under drought stress in Breda (1983/84), and under dryland salinity stress in Hegla (1982/83/84) in Syria. Mean grain yield levels ranged between 260 kg/ha and 4850 kg/ha. Under drought and salinity stress, the majority of the landrace lines out-yielded the best cheeks significantly. In Tel Hadia the check cultivars mostly outyielded the landrace lines, but not always significantly. In all environments the harvest index of the landrace lines was near the optimum for barley. They expressed intermediate plant height and time to flowering, high lodging susceptibility under favorable growing conditions, high protein content, and a wide range of yield component combinations. In the stress environments highly significant genetic variation among the landrace lines was found. The heritabilities for gram yield were high in these trials. The correlations between performance under stress and under favorable growing conditions were poor. Therefore, the largest gains for variety improvement for the Syrian steppe area are expected from direct selection under stress conditions. Unique responses in proline accumulation and germination patterns in saline solution indicated specific adaptation in this material. These landraces, thus, are a useful source of breeding material, which also widens the genetic base of the present breeding program.  相似文献   
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