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71.
为了能科学地确定训练的重点,为网球教练员和运动员训练决策提供依据。综合使用测试法、变异系数和TOPSIS法对浙江省现役网球运动员体能的测试数据进行处理。结果:男队训练重点排序为:力量、爆发力、灵敏、速度、耐力;同理,女队训练重点的排序为:力量、爆发力、灵敏、耐力、速度;最后对每位运动员亟待加强指标进行排序。结论:变异系数和TOPSIS法计算的结果简单明了,节省资源,适宜不同专项、不同训练指标的训练过程的有效监控。  相似文献   
72.
为了探讨两种同期发清处理方法和不同年龄阶段对非繁殖季节奶山羊同期发情效果的影响,选用12∽15月龄初产奶山羊和4∽5胎经产奶山羊分为两组,采用孕激素耳栓埋植和阴道栓塞两种处理,并辅以肌注PMSG及PG-CL、E2,每组试验重复2次.结果显示:孕激素耳栓埋植法和阴道栓塞法两种同期发情处理方法处理初产组奶山羊总发情率分别达到87.5%和100.0%,经产组分别达到77.8%和83.3%,均无显著差异(P>0.05).但两种方法0∽24 h内的同期发情率初产组阴道栓法平均为94.1%,耳栓法平均为37.5%,差异显著(P<0.05),经产组阴道栓法平均为61.1%,耳栓法平均为44.4%,差异亦显著(P<0.05);无论初产、经产组奶山羊阴道栓法处理0∽24 h内的同期发情率(分别为94.1%、61.1%)显著高于24∽36 h发情率(分别为5.9%、22.2%)(P<0.05).用阴道栓同一种方法处理初产和经产奶山羊,初产组24 h的同期发情率(86.7%)显著高于经产组(60.0%)(P<0.05).阴道栓法处理同期发情效果优于耳栓法,初产奶山羊的同期发情效果优于经产奶山羊.  相似文献   
73.
利用1980~2013年南京国家基本气象站的地面常规气象要素和能见度观测资料,剔除相对湿度和天气现象对能见度的影响,采用等级分析法、"非常好"能见度出现频率法、累积百分率法、Ridit中值分析等方法,分析了南京地区大气能见度的年际和季节变化趋势;并利用偏相关分析法分析了能见度与气温、气压、平均风速和相对湿度的相关关系。结果表明,能见度有明显日变化和季节变化,一天中,8:00最差,14:00最好;一年之中,能见度夏季最好,冬季最差。1980~1984年南京能见度呈上升趋势,1985~2004年呈波动下降趋势,2005~2013年则呈缓慢上升趋势;"较差"和"一般"能见度出现频率呈现上升趋势,"较好"能见度出现频率则明显下降。能见度水平逐年代下降但降幅减小;能见度等级分布的季节差异逐年代减小。能见度与平均风速呈正相关,与相对湿度呈负相关。由于南京地区气候条件的影响,能见度与气压和气温均存在季节性差异,能见度与气压在冬季呈较好的正相关,与气温夏季呈正相关、冬季呈负相关。  相似文献   
74.
熊寿福  张健 《种子》1991,(4):28-31
穗长、穗粒重两性对小区产量直接影响较大;每穗实粒数和每穗不实粒两性状数对小区产量直接影响很小,但通过其他性状对小区产量的间接负影响很大;每穗总粒数对小区产量直接负影响很大,株高通过其他性状对小区产量间接正影响很大。  相似文献   
75.
Six stability statistics: (bi, s2di, , , and ) were estimated for maize, wheat and sorghum in different environments by using three statistical models. The significant linear portion of genotype × environment interaction for maize indicates different hybrids responded differently to environments, whereas the non-significant genotype × environment interaction (linear) were found for wheat and sorghum suggest that all genotypes responded similarly as the environments change. However, the highly significant pooled deviations (deviation from regression) for all three crops make yield predictions from the model less reliable. When regression coefficients (bi) were non-significant, s2di, became an important statistic in estimating stability. It appears that the regression coefficient, bi, was best used to estimate genotypic adaptability, whereas s2di, for stability. Maize and sorghum had negative correlations between the mean yield and stability statistics, s2di, , and , suggesting that high yield and stability are not mutually exclusive in the range of environments used in this study; however, such correlations did not occur in wheat. Thus, maize and sorghum hybrids with high yield potential and high stability could be identified and selected. Correlations between mean yield and bi, or , were positive and significant for maize and sorghum but were non-significant for wheat, indicating that such relationships may be species specific. Under a given set of testing environments, the stability ranking associated with each maize hybrid is correlated to and depends on other hybrids included in the analysis.  相似文献   
76.
Quantitative information regarding biomass accumulation and partitioning in chickpea (Cicer arietinum L.) is limited or inconclusive. The objective of this study was to obtain baseline values for extinction coefficient (KS), radiation use efficiency (RUE, g MJ?1) and biomass partitioning coefficients of chickpea crops grown under well‐watered conditions. The stability of these parameters during the crop life cycle and under different environmental and growth conditions, caused by season and sowing date and density, were also evaluated. Two field experiments, each with three sowing dates and four plant densities, were conducted during 2002–2004. Crop leaf area index, light interception and crop biomass were measured between emergence and maturity. A KS value of 0.5 was obtained. An average RUE of 1 g MJ?1 was obtained. Plant density had no effect on RUE, but some effects of temperature were detected. There was no effect of solar radiation or vapour pressure deficit on RUE when RUE values were corrected for the effect of temperature. RUE was constant during the whole crop cycle. A biphasic pattern was found for biomass partitioning between leaves and stems before first‐seed stage. At lower levels of total dry matter, 54 % of biomass produced was allocated to leaves, but at higher levels of total dry matter, i.e. under favourable and prolonged conditions for vegetative growth, this portion decreased to 28 %. During the period from first‐pod to first‐seed, 60 % of biomass produced went to stems, 27 % to pods and 13 % to leaves. During the period from first‐seed to maturity, 83 % of biomass was partitioned to pods. It was concluded that using fixed partitioning coefficients after first‐seed are not as effective as they are before this stage. Environmental conditions (temperature and solar radiation) and plant density did not affect partitioning of biomass.  相似文献   
77.
A simple procedure for yield component analysis   总被引:3,自引:0,他引:3  
H. -P. Piepho 《Euphytica》1995,84(1):43-48
Summary This paper introduces a simple method of analysing yield components. It allows quantification of the contribution of each component to the variability of final yield. The method is based on log-transforms of measurements of the component traits. Applications in heterosis breeding and stability analysis are discussed. The method is compared to other procedures of yield component analysis.  相似文献   
78.
Summary The effect of self-pollination of cucumber (Cucumis sativus L.) for 6 generations in lines developed from the North Carolina Medium Base Pickle population was determined by regression of trait expression for each generation on Wright's coefficient of inbreeding. Two yield traits (total and marketable), earliness and 3 fruit quality traits (shape, color and seedcell size) were evaluated in 2 environments (spring and summer, 1983). The regression did not result in significant negative slopes, indicating that inbreeding depression was not important in the population for the traits studied. Midparent heterosis was found for most traits in many hybrids obtained from crossing S6 lines with the gynoecious inbred line, Gy 14A.  相似文献   
79.
保护性耕作具有提高作物水分利用效率、减少能耗等优点,但能否将该技术集成应用于间作套种,尚需理论研究和具体实验依据。本研究通过2011至2012年度的田间定位试验,探讨不同耕作和秸秆还田方式对小麦间作玉米作物群体竞争、互补作用及产量的影响。试验设3种秸秆还田处理,分别是小麦带25 cm高茬收割立茬免耕(NTSS)、小麦带25 cm高茬等量秸秆覆盖免耕(NTS)及小麦带高茬等量秸秆还田翻压(TIS),以传统耕作(CT)为对照。秸秆还田后少耕间作的土地当量比高于传统耕作间作,且大于1,说明少耕小麦秸秆还田有利于提高间作优势;少耕秸秆还田降低了共生期小麦相对于玉米的竞争力,以NTS处理对小麦竞争力的影响最大,NTSS、NTS和TIS的小麦全生育期相对竞争力分别降低37%~54%、109%~141%和22%~24%。与单作玉米相比,NTSS、NTS、TIS和CT处理间作玉米的相对生长率分别高54%~59%、66%~71%、61%~63%和71%~78%,其中小麦秸秆还田间作处理中NTS更有利于发挥玉米的恢复效应。间作条件下,3种秸秆还田处理的产量较对照高6%~10%(2011年度)和4%~12%(2012年度),其中NTS增产显著。总体来看,间作群体籽粒产量与小麦相对于玉米全生育期的平均竞争力呈二次相关关系,当该竞争力在0.24~0.27时利于获得间作高产。本研究表明,秸秆还田配合少耕是调控种间竞争力的可行途径,其中小麦等量秸秆(小麦留茬25 cm)还田覆盖是优化小麦玉米竞争力的理想耕作措施。  相似文献   
80.
为了选择重金属污染土壤生态修复植物,利用采样测试分析的方法,对生长于冷水江严重Sb、As、Cd、Hg污染土壤的大叶女贞进行了研究。结果表明:大叶女贞能耐较严重重金属胁迫,其生长量、生物量受影响较小,胸径、树高和生物量分别减少2.58%、6.07%、7.58%;大叶女贞对各重金属的富集系数均大于2,其中Hg、Cd的富集系数最大,Cu、As的富集系数最小;对各重金属的转运系数均大于60,其中Sb的转运系数最大,Zn的转运系数最小;各重金属在大叶女贞根、茎、叶器官内的富集量有极显著差异,根、茎、叶等器官间富集的重金属有极显著差异,其叶部富集重金属的顺序为ZnSbAsPbCuCdHg,茎部富集重金属的顺序为ZnSbPbCdAsCuHg,根部富集重金属的顺序为ZnSbPbAsCuCdHg,叶、茎、根三器官富集各种重金属的顺序为叶茎根,至少有93.0%重金属富集在叶、茎、枝等地上部器官,其中至少有60.0%的重金属富集在叶部;大叶女贞为一优良重金属污染土壤生态修复树种。  相似文献   
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