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11.
通过测定9个生育期北乌头根、茎、叶中矿质元素的质量分数,研究北乌头生长季各器官中矿质元素的变化规律及其在各器官中的分配规律,结果表明:北乌头中各营养元素质量分数从高到低的顺序为N、K、P、Ca、Mg、Fe、Zn、Mn、Cu;北乌头各器官营养元素质量分数存在明显的生育期变化,出苗期北乌头根和叶中N、P、K和Cu质量分数均显著降低,开花期根和叶中N、P和Cu质量分数均显著升高,果期北乌头叶片中P、Mg和Fe质量分数均显著升高;除Cu和P外,其他营养元素在北乌头叶中质量分数最高,并且多数营养元素在叶中分配比例较高;北乌头各器官中营养元素间存在一定相关关系,并以协同作用为主;北乌头有3个养分需求高峰期,即出苗期、开花期、结果期,且每个时期需求养分的种类也不同。  相似文献   
12.
不同谷子品种形态特征和光合生理特性分析   总被引:2,自引:0,他引:2  
以14个常规谷子栽培品种为试验材料,在相同栽培条件下,研究了其主要形态特征指标、光合生理特性指标和产量的变化,结果显示,参试品种的形态特征指标、净光合速率和产量均存在较大差异,其中,品种间净光合速率存在极显著差异,且抽穗期和灌浆期间的净光合速率差异大于品种间的净光合速率差异。并对形成产量的主要性状指标与产量参数的相关性进行了分析,结果显示,谷子净光合速率与产量呈显著正相关,且灌浆期的显著性水平高于抽穗期;水分利用效率和叶绿素含量与产量呈正相关,单穗重、穗粒重、出谷率和千粒重与产量呈负相关,但相关性均未达到显著水平;千粒重与净光合速率、水分利用效率和叶绿素含量的相关系数均不高,且相关性均未达到显著水平;抽穗期净光合速率与叶绿素含量的相关系数(0.492)灌浆期净光合速率与叶绿素含量的相关系数(0.232),在叶片叶绿素含量较低时增加叶绿素含量可以提高谷子的净光合速率,但当叶片叶绿素含量达到一定程度后,再增加叶绿素含量,谷子的净光合速率不一定继续增加。  相似文献   
13.
Data from a trial of 36 families at Little Wittenham, North Oxford was used to assess growth traits and stem form in common ash (Fraxinus excelsior, L.). The trial followed a design described by Barnes (Silv Genet 44(2–3):81–88, 1995) as the Breeding Seedling Orchard (BSO). The objectives of the study were to determine variation in growth and form traits and estimate genetic parameters of families. Assessments conducted at 3–8 years for height, diameter at breast height (dbh), straightness and forking showed significant differences (P < 0.05) among families with Guys (19), Settrington (34), Overbury (23) and Grimthorpe (36) being the best performers while Coleford (3 and 5) Gwynedd (27) and Bacheiddon (32) were the least performers. At the overall level, the additive genetic coefficient of variation (CVA) ranged between 10.2 and 12.7% for height and 1.5 and 2.1% for dbh. Height had a high genetic correlation (rg = 0.85) with dbh whilst forking had low correlation (rg = 0.25) with height. Estimates of heritability decreased with age from  = 0.62 at 3 years to  = 0.30 at 8 years for height while values for dbh decreased from  = 0.48 at 4 years to  = 0.27 at 8 years. Some genetic gains are possible despite the low genetic variation among families; height had the greatest potential of genetic gain (12.5% at 8 years). Results suggest that early selection of superior families of Fraxinus excelsior appears to be feasible and it could be possible to achieve simultaneous improvement in both growth and form.  相似文献   
14.
以色列野生二棱大麦农艺性状差异及相关性分析   总被引:7,自引:0,他引:7  
严俊  程剑平 《麦类作物学报》2007,27(6):969-973999
为给野生大麦的遗传和基因资源的研究提供依据,对起源于以色列不同地区6个群体的16个生态型野生二棱大麦的物候性状进行了研究.结果表明,不同生态型间的物候性状差异明显.从个体水平上分析,其最大值均出现在湿生生态型中,除旗叶面积外,其最小值则出现在旱生生态型中;从群体水平上分析,除每穗粒数外,湿生型平均值皆高于旱生型平均值.曼-怀氏等级和检验显示,湿生型和旱生型之间的这些物候性状差异达到显著水平.斯皮尔曼秩相关性检验则表明,9个物候与性状间,除三叶期与粒重、穗粒重无相关性外,其余物候性状间均呈显著的相关性,其中生长期与旗叶面积、株高、穗长、芒长等呈显著正相关,与每穗粒数则呈显著负相关;芒长与旗叶面积、株高,稳长与株高存在显著正相关,而每穗粒数则与芒长和旗叶面积分别呈显著负相关,芒长与穗长亦呈显著正相关.分析表明,以色列不同地区野生大麦物候性状差异是其生境主导下生存选择的结果,其丰富的表现型多样性,可用于遗传与育种研究.  相似文献   
15.
The main objective of this study was to investigate possibilities to increase accuracy in the selection and test of Swedish warmblood stallions by combining information from stallion performance tests (SPT) with information from competitions and riding horse quality tests (RHQT). Data on 801 stallions judged at the SPT 1979–2005 were used for the analyses, which also included about 14 900 horses from the RHQT, 26 800 horses with results in show jumping and 14 200 horses with results in dressage competitions.Heritability coefficients were on average 0.41 for individual gaits under rider and 0.36–0.65 for jumping traits in SPT. Heritabilities for competition traits were 0.17 for dressage and 0.27 for show jumping. The heritability for overall conformation in SPT was 0.25. Genetic correlations between stallion performance test traits and competition results were 0.44–0.77 for gaits and dressage, and 0.78–0.96 for jumping traits in SPT and show jumping. The genetic correlation between conformation and results in dressage competitions was 0.22.For stallions participating in SPT in 2004 and 2005 accuracy increased when evaluating stallions by adding information from relatives that have taken part in RHQT and competitions. For show jumping accuracy changed from 0.60 to 0.68 for stallions born in Sweden, an increase with 13%, when information from RHQT and competitions in show jumping were used. For stallions born in a foreign country, the corresponding figure was, 5%, lower. For dressage the information from RHQT and competition results in dressage changed the accuracy from 0.41 to 0.55, an increase with 34%, for stallions born in Sweden. The improvement in accuracy for imported stallions was 11%.  相似文献   
16.
以东北5个白桦天然林种群为对象,较全面地研究了白桦木材材质性状的差异及相关性。结果表明:天然林白桦种群间木材纤维宽度、长宽比、木材基本密度、胞壁率、微纤丝角、导管比量、小拉什强度和年轮宽度差异显著或极显著;木材纤维长度、纤维壁腔比、木射线比量和纤维比量差异不显著。白桦导管比量与均温和降雨量、胞壁率和木材基本密度与经度呈显著负相关(r>0.9)。在种群间木材基本密度与胞壁率呈显著正相关(r>0.9);纤维宽度与胞壁率、纤维壁腔比、长宽比呈显著负相关(r>0.8),纤维长度与微纤丝角呈负相关(r=-0.97)。  相似文献   
17.
对9个春播芝麻品种(系)的主要性状与单株产量进行了相关及通径分析,结果表明:单株蒴果数、千粒重和株高的直接效应较大。因此,在选育高产品种时,应以单株蒴果数多、千粒重高和植株较大的类型作为主要选择目标。  相似文献   
18.
对羊毛纤维直径与毛量、体重、毛量组成成分、羊毛弯曲度、羊毛纤维强度、体脂含量、繁殖性能等性状的相关性研究进展及现状进行了综述。  相似文献   
19.
在桔梗开花期,计算桔梗开花后每5 d的千粒质量和成熟度的增长量,分析桔梗种子成熟度与主要气象要素之间的关系。结果表明:在吉林省桔梗种子要完全成熟,开花后需要55 d以上的时间;种子成熟与主要气象要素之间没有显著的相关性,种子成熟主要受桔梗本身发育规律支配。  相似文献   
20.
Abstract

Certain soils in the Lower Atlantic Coastal Plain are Mn‐deficient and because of their inherent properties, deficiencies of other elements might be expected. The response of soybean [Glycine max (L.) Merr. cv. ‘Ransom'] to annual soil applications of B, Cu, Fe, Mo, S, and Zn with and without Mn was examined. The study was conducted on an Olustee‐Leefield sand (Ultic Haplaquod‐Arenic Plinthaquic Paleudult) in 1975, 1976, and 1977. Seed yields, and soil and plant tissue concentrations of certain of the applied elements were determined. Soil pH increased from 6.4 in 1975 to 7.0 in 1977 as a result of lime applications.

Of the seven elements studied, only Mn significantly increased soybean seed yield compared to the check. Leaf concentrations of the respective elements were higher where the element was added than they were in plants grown on the check plots. In 1977, after three years of elemental additions, plant concentrations of Mn, Cu, and Zn were higher, relative to checks, than in 1975. In 1977, with the higher soil pH levels, plants from check plots had lower concentrations of Mn, but unexpectedly equal levels of Cu and higher levels of Zn than in 1975. This unexplained increase in plant Zn was also found in Other experiments in the same field during the same time period. Double acid extracted more soil Mn, Cu, and Zn than did DTPA from similar treatments during all three years. The DTPA‐extractable soil Mn correlated much better with plant Mn than did double acid Mn values, especially over years where a change in soil pH occurred. Correlation coefficients comparing extractable soil versus plant values for Cu and Zn data combined over years were higher for double acid than DTPA, although coefficients for the Cu and Zn data were still generally much lower than for the Mn data.  相似文献   
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