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1.
准确、及时地监测区域作物长势状况对农业规划和政策的制定与调整具有重要的意义。遥感技术作为一种收集大面积作物长势信息的有效手段,正日益受到关注。为提高冬小麦长势遥感监测的准确性和全面性,该研究基于田间实测的冬小麦拔节期地上鲜生物量(aboveground fresh biomass,AFB)、叶面积指数(leaf area index,LAI)、叶片叶绿素相对含量(soil and plant analyzer development,SPAD)和叶片氮含量(leaf nitrogen content,LNC)4种生长相关理化参数,利用熵值法获取各参数权重构建冬小麦理化复合参数(physico-chemical composite parameter,PCCP)。利用显著性检验和籽粒产量数据分析复合参数在量化冬小麦长势方面的性能。然后,以Sentinel-2A作为数据源,分析不同遥感指数与LAI、SPAD、AFB、LNC和PCCP的相关性。选取相关性较高的遥感指数作为反向传播(back propagation,BP)人工神经网络(artificial neural networks,ANN)的输入,建立冬小麦长势遥感监测模型,对PCCP进行估计。评价模型精度并用于监测研究区冬小麦长势分布特征。赋权结果表明,作物物理参数的权重大于生化参数,其中LAI的权重最大,为0.387,AFB和SPAD次之,LNC的权重最小,为0.105;PCCP性能评估结果表明,与单一理化参数相比,PCCP值能更好地揭示作物长势状况的差异,其与最终籽粒产量的相关性更好, 决定系数提高0.035~0.468,均方根误差减少46.2~520.0 kg/hm2;在遥感监测过程中,PCCP比单一理化参数有更好的应用潜力,BP-ANN长势遥感监测模型模拟PCCP精度较高,在测试集中决定系数为0.830,均方根误差为0.080;研究区冬小麦总体长势稳定且分布集中,呈现"中部差,南北好"的空间分布特征。因此,构建作物理化复合参数用于量化作物长势是提高长势监测可靠性和准确性的一种有效方式,可为冬小麦田间管理提供科学依据,服务于发展智慧农业和建设农业强国的战略需求。  相似文献   
2.
甘蓝型油菜含油量的遗传研究   总被引:5,自引:0,他引:5  
采用7×7双列杂交设计,研究了甘蓝型油菜含油量的基因作用和其它遗传参数,以及含油量与其它农艺性状、品质性状的关系。结果表明:含油量的遗传符合加性—显性遗传模型,有关基因在亲本中呈独立分布;显性指向增效,表现超显性作用;亲本中显性基因比隐性基因多,增效基因比减效基因的频率大;控制含油量并表现显性的基因约为4组;含油量的广义和狭义遗传力分别为81.16%和30.90%。单相关和逐步回归分析一致表明,单株产量、每角粒数、主花序长度和株高对含油量有较强正向作用,但角果长度和全株总角果数的作用为负。本文还讨论了基因作用分析在探讨配合力的基因效应成分和杂种优势产生的可能原因中的意义,及其在选择中的应用。  相似文献   
3.
为了研究郁金散加减方对长白猪传染性胃肠炎的治疗效果,从张家口顺德猪场选取患有传染性胃肠炎的成年长白猪20头,随机分为郁金散加减方低剂量组、郁金散加减方高剂量组、西药组和对照组,每组各5头。郁金散加减方组每天灌服郁金散方剂,早晚各1次,低、高剂量组分别按6、7mL/kg体重给药;西药组每天灌服金刚乙胺,颈部皮下注射氟苯尼考,早晚各1次;对照组正常饲喂,不给药。7d后观察临床症状和生长性能,测定血常规、血清生化指标、血清免疫指标及抗氧化指标。结果表明:郁金散加减方组和西药组病猪反应灵敏,体温正常,进食量增加,粪便恢复正常。低、高剂量组和西药组治愈率分别为80%、90%和60%,郁金散加减方的治疗效果优于西药治疗。与对照组相比,高剂量组能极显著提高猪平均日增重(ADG)和平均日采食量(ADFI)(P<0.01),极显著降低料重比(P<0.01);3个给药组均能极显著降低血尿素氮(BUN)、丙二醛(MDA)和白细胞数量(WBC)(P<0.01),极显著提高血清钾(K)、总蛋白(TP)、白蛋白(ALB)、球蛋白(GLB)含量和总抗氧化能力(T-AOC)(P<0.01),但3组间差异不显著(P>0.05);高剂量组过氧化氢酶(CAT)活性极显著高于低剂量组、西药组和对照组(P<0.01)。表明郁金散加减方对长白猪传染性胃肠炎有较好的治疗效果,其中郁金散加减方高剂量组效果更好。  相似文献   
4.
1. The aim of the study was to estimate the heritability of the laying performance in the cumulative and partial production of eggs and predict the breeding values of native Zatorska geese in a conservation programme using Best Linear Unbiased Prediction (BLUP) methodology. Second, the trajectory of the egg production curve was examined.

2. The data contain information about the laying performance of 1831 individuals in the first year of laying. To describe the trajectory of the laying performance, 10 mathematical models were tested. For the genetic parameter estimation of egg production, data from 1038 birds were used with a production higher than 20 eggs during the first season of laying.

3. The analysis of egg production was based on single and multi-trait models. Heritability, genetic and phenotypic correlations between phases of the laying performance as well as breeding values were estimated.

4. The best adaptation to the goose egg laying curve was the Ali and Schaeffer model. The estimates of heritability were 0.20 (0.06 SE) using the single-trait model and ranged from 0.12 to 0.24 using the multi-trait model.

5. The results suggest that the BLUP method can support the conservation programme.  相似文献   

5.
应用动物模型REML法估计金华猪繁殖性状遗传参数   总被引:9,自引:0,他引:9  
试验资料取自金华猪场 1 979~1 999年金华猪繁殖性能的生产记录。采用动物模型约束性最大似然法 (REML)对该猪群的遗传参数进行估计 ,测定 1 1 4 4头纯繁金华母猪的产仔哺育记录。结果表明 ,产仔数 (TNB)、产活仔数 (NBA)、初生重 (PBW)、初生窝重 (LBW)、 2 0日龄头数(NFC)、 2 0日龄窝重 (LWFC)、 2 0日龄重 (PWFC)、 60日龄头数 (NW)、 60日龄窝重 (LWW)、 60日龄重 (PWW)、乳头数 (TN)的遗传力分别为0 1 2± 0 0 9、 0 1 8± 0 1 1、 0 1 5± 0 0 9、 0 0 2± 0 0 9、 0 1 0± 0 1 1、 0 0 8± 0 1 3、 0 1 8± 0 1 0、 0 2 3± 0 1 1、 0 31± 0 1 3、 0 35± 0 1 1和 0 1 9± 0 1 0。TNB与NBA、LBW、NW、LWW的遗传相关范围为 0 66~ 0 88,TNB与PBW的遗传相关为 - 0 43。NBA与LBW、NW、LWW的遗传相关范围为 0 60~ 0 64,NBA与PBW遗传相关为 - 0 63。PBW与PWW的遗传相关为 0 51。  相似文献   
6.
The objectives of this study were to estimate the environmental and additive and non-additive genetic effects on lactation curve and lactation parameters of crosses of Holstein (H), Brahman (B) and Brown Swiss (BS) in Olancho region in Honduras. The data consisted of 54,517 milk yield records from 192 dual-purpose crossbred cows lactating from 2000 to 2005 at the Universidad Nacional de Agricultura de Honduras (UNA). The lactation curve and lactation parameters of interest were the scaling factor to represent yield at the beginning of lactation (a), the factor associated with the inclining (b) and declining (c) slopes of the lactation curves, and the milk yield at initial day of lactation (MY20), peak milk yield (MYmax), day at peak milk yield (tmax), and the total milk yield (TM) per lactation, respectively. The incomplete gamma function (Wood function) was used to estimate lactation curve and lactation parameters from daily milk records of H × B, H × BS and BS × B crossbred cows. The environmental, additive and non-additive genetic effects on lactation curve and lactation parameters were estimated using Dickerson and Kinghorn models. The coefficients of determination of fitness of Wood's function (R2) ranged from 80% to 97% with an average of 93%. The lactation curve of the crossbred cows was similar to those reported for dairy cows grazing in the tropics. Lactation parameters such as MYmax, tmax and TM were significantly (P < 0.05) influenced by environmental sources of variation suggesting the necessity of differential management strategies. The moderate to large positive phenotypic correlation of MYmax and TM indicate that one of the milk yield parameters could be used as a selection criterion to improve either one or both traits. Despite the fact that both genetic models showed similar patterns, the absolute value of the parameters varied. For both models, individual additive genetic breed effect for H breed were significant (P < 0.05) and contributed more to TM than the BS breed. In the Dickerson model, highly positive significant (P < 0.01) effect on TM for H×BS and BS×B crosses was found. The Kinghorn model did not show significant effects of dominance on this parameter. The estimate of recombination effect for all crosses involving B breed were negative and significant (P < 0.05) for positive correlated lactation curve parameters. Although the inclusion of non-additive effects on crossbreeding genetic effects were not all significant for lactation curve and lactation parameters, non-additive effects should be taken into account to improve the Honduran dairy cattle production management.  相似文献   
7.
γ-氨基丁酸对夏季生长肥育猪血清生化指标的影响   总被引:3,自引:0,他引:3  
将48头体重43kg左右的"杜×长×大"三元杂交猪随机分成两组,饲喂在基础日粮中添加0、10mg/kgGABA的日粮。结果表明:添加GABA使血清中钙、磷、钾、氯4种无机离子浓度提高,差异不显著(P>0.05);总蛋白、白蛋白、尿素氮水平有提高趋势,差异不显著(P>0.05),葡萄糖水平提高13.29%,差异显著(P<0.05);丙氨酸转氨酶、天门冬氨酸转氨酶活性上升,差异不显著(P>0.05),乳酸脱氢酶、肌酸磷酸激酶活性分别下降16.93%(P<0.05)、38.22%(P<0.01);谷胱甘肽过氧化物酶(GSH-Px)、超氧化物歧化酶(SOD)活性均有上升,其中GSH-Px差异极显著(P<0.01),丙二醛含量下降(P>0.05)。  相似文献   
8.
The aim of this study was to evaluate the effect of acupuncture (AG) treatment on some hematochemical parameters in five Thoroughbred horses after road transport and exercise. Horses competed in two official races. For each race, animals were transported from their stables to the racetrack. Horses transported and competed in the first race represent the control group. Two weeks later, the same horses competed in the second race. Before road transport, they were treated with AG. From animals, blood samples were collected at rest (TPRE), after unloaded (TPOST), 30 minutes after unloaded (TPOST30), at rest in the transit stall (RPRE), at the end of the race (RPOST), and 30 minutes after the race (RPOST30). The effect of transport, exercise, and AG was evaluated on blood lactate, glucose, red blood cell, hemoglobin, hematocrit, mean corpuscular volume, and erythrocyte osmotic fragility (EOF) values. A significant effect of transport (P < .05) and exercise (P < .01) was found on all studied parameters in both groups. A significant effect of AG on lactate, glucose, and EOF values was found in transported (P < .001) and exercised horses (P < .05). The results found in this study showed that transport and exercise are potential stressors for the athlete horse that may affect its welfare and physical performance. The data suggest that AG stimulation promoted the increase of blood glucose values and the reduction of lactate and EOF levels suggesting its role in the improvement of the physiological adaptation to stressful stimuli and of physical performance of Thoroughbred horses.  相似文献   
9.
采用双螺杆膨化机干法工艺对宠物全价粉状饲料进行膨化并制粒,研究所得产品的容重与淀粉糊化度、硬度指标之间的关系,以及设备参数和配方特性对颗粒饲料容重的影响。结果表明:容重与淀粉糊化度、硬度密切相关;设备参数与配方特性均对产品容重有极显著影响;通过容重的测定估测其熟度和硬度具有可行性;可以通过调节喂料速度和膨化玉米比例控制产品容重。  相似文献   
10.
采用多性状动物模型BLUP和非求导约束最大似然法(MTDFREML)估计了引进罗曼蛋鸡纯系配套组合中4个品系9个性状的方差组分和遗传参数,并估计了固定效应的BLUE值和动物个体的加性遗传效应值(育种值),分析了测定性状的世代间遗传趋势和表型趋势。结果表明,4个系各性状的遗传力基本一致,体重、蛋重以及不同周期的产蛋量之间存在显著的正相关。蛋重与产蛋量存在较强的遗传负相关。六个世代选育后,各品系蛋重、产蛋量的平均育种值均有提高,表明对产蛋量和蛋重的选择是有效的。  相似文献   
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