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11.
Summary Relationships among the traits protein percentage, grain yield, and protein yield of oats were studied with F2-derived lines in F3 and F4 from 27 matings obtained by crossing high-protein with high-yield oat lines. High-protein parents were (a) selections from an Avena sativa bulk, (b) selections from three-way matings in which an initial parent was A. sterilss, and (c) cultivars. High-yield parents were derived from backcross populations involving A. sterilis accessions as donor parents.Significnnt genetic variation existed among F2-derived lines for grain and protein yield in all matings and for protein percentage in all but one mating.Protein percentage had a highly significant negative correlation with grain yield (r=–0.33**) when pooled over all matings, but in five, these two traits were not correlated. Overall, protein percentage showed a small negative correlation with protein yield (r=–0.09*), and protein and grain yields had a high positive association (r=0.98**). F2-derived lines with both high protein percentage and high grain yield were obtained.High transgressive segregates for protein percentage occurred in two matings, for grain yield in nine, and for protein yield in 14. Most high transgressive segregates for protein yield were high because of high grain yield only, but in four matings, lines were found where protein yield was increased by concurrent increases in both protein percentage and grain yield.Only a few specific parental combinations between high-protein and high-yield parents produced segregates in which increased protein percentage contributed materially to high-protein yields.Journal Paper No. J-11264 of the Iowa Agriculture and Home Economics Experiment Stn., Ames, Iowa 50011. Project 2447.  相似文献   
12.
The previously found wide range in the ratios of avenin or methanol-precipitated fractions to residual proteins was revisited by studying 75 oat varieties, mainly representing landraces from Finland, and included old varieties or selections, cv. Kytö, synthetic hexaploid oats and an Avena strigosa line (HA 71–87). The means of the fraction ratios ranged from 4.17 to 6.46 with significant differences. Samples of 10 narrow-ratio and 10 wide-ratio oats were compared more closely. The wide-ratio sample had significantly higher total protein content and significantly lower content of the methanol-precipitated protein fraction. Therefore, both fractions in general appear to contribute to the ratio of the protein fractions. The wide-ratio sample had significantly lower grain mass and husk-free karyopsis mass. Samples of the extreme ends in the ratios of the protein fractions showed different electrophoretic protein patterns, which was also seen in samples representing the same population of origin. It is evident that polymorphisms in the protein fractions would allow breeding of oat cultivars showing further lowering of proteins putatively toxic to coeliacs assuming oats contain these toxic proteins.  相似文献   
13.
通过不同杀菌剂拌种防治莜麦坚黑穗病试验,筛选出成本低、防效高的几种杀菌剂,可有效控制莜麦坚黑穗病的危害。  相似文献   
14.
A lysimeter study was conducted to investigate how nitrogen uptake of spring wheat and oats and N leaching losses are differing when either oilseed rape or faba bean are grown as green manure. The experiment was conducted during 1982–1988, and fertilizer applied to the cereals was either farmyard manure, FYM, (6 and 12 g N/m2/year) or mineral fertilizer, MiF, at a rate of 6 g N/m2. On average of the 7 year period faba bean increased N uptake of the cereals fertilized with FYM at harvest by 3–4 g/m2. Differences between the two application rates were negligible. N-leaching losses increased twofold when faba bean was grown instead of oilseed rape. Growing faba bean after cereals supplied with MiF, too, increased N uptake of the cereals and significantly increased leaching losses.  相似文献   
15.
为探讨起源地生态地理因素对野生燕麦物候期和农艺性状的影响,对种植于成都金堂试验地的源自以色列不同地区7个野生燕麦群体70个基因型的19个物候和农艺性状进行了测定,并用单因素方差(One-Way ANOVA)、相关性网络(Correlation-based network analysis,CNA)、斯皮尔曼秩相关(Spearmanp’s Rho Correlation)等方法进行数据分析。结果表明,不同群体和基因型间的物候期和农艺性状差异明显。其中,全生育期最短的群体是Sede Boqer,来自该群体的SB14-07的生育期仅170.0d;最大单株生物产量出现在Caesarea群体中,达268.1g;而千粒重最大的是来自Tabigha群体的Tg-09,为28.8g。起源地水分、温度、地理等因素对野生燕麦的物候及农艺性状起不同程度的关键性影响。以上结果说明,野生燕麦物候及农艺性状差异的实质是其长期与环境相互作用,在自然选择压力下进化形成的遗传多样性。  相似文献   
16.
14份燕麦种质在肃南皇城镇的生产性能比较   总被引:1,自引:0,他引:1  
对14份燕麦(Avena sativa)种质株高、产草量、营养、种子产量、千粒重、发芽率等方面进行评比研究,以期筛选出适宜在甘肃省肃南县皇城地区种植的燕麦种质。结果表明,青永久479号植株高度最高,达到151.3 cm;青永久474号最矮,为128.4 cm。青永久12号分蘖最多,为2.0;其余燕麦种质的分蘖都低于2.0。叶茎比变化在1.79~2.46,青永久195号叶茎比最高(2.46),陇燕2号最低(1.79)。陇燕2号干草产量最高,为11.11 t·hm~(-2);巴燕3号最少,为7.71t·hm~(-2)。青永久416号干草粗蛋白含量最高,为8.2%;青永久195号的最低,为6.3%。青永久97号干草酸性洗涤纤维含量最高,为47.4%;加燕2号的最低,为37.4%。中性洗涤纤维含量最低的是青永久233号,为59.5%;陇燕2号最高,为66.7%。巴燕3号、青海444、青永久93、青永久474和甘南燕麦种质能够成熟,适宜籽实农业生产,其中种质甘南的千粒重、发芽率以及种子产量表现最好。综合结果表明,青永久479、青永久167和青永久233适宜在肃南皇城进行营养体农业生产。  相似文献   
17.
The versatility of mixed model procedures in investigating large, unbalanced sets of genotype by environment data is illustrated on an historic set of yields from a South Australian oat evaluation program. Information on specific genotypic traits is included in the analysis in order to isolate unexplained genotype by environment interaction.  相似文献   
18.
以4个引种燕麦(Avena sativa)为典型代表,对其不同生育时期根、茎、叶中的C、N、P含量及其化学计量学特征进行测定,探讨不同生育时期燕麦C、N、P元素含量及其化学计量比的变化规律,为燕麦饲草的科学收获提供理论依据。结果表明:燕麦全株C、N、P含量分别为322.30~333.97、17.42~75.62、2.74~5.42 mg·g-1,燕麦根C、N、P含量分别为298.42~317.92、11.47~73.71、2.82~3.42 mg·g-1,燕麦茎C、N、P含量分别为311.25~338.86、10.15~75.16、2.44~5.06 mg·g-1,燕麦叶C、N、P含量分别为330.80~372.47、30.64~113.80、2.59~8.65 mg·g-1;各器官间C、N、P含量表现为叶>茎>根。此外,燕麦各器官C、N、P含量的积累过程具有一定季节特征,C含量积累过程受生育时期影响较小,表现出较强的稳定性;而N和P含量的积累过程受生育时期影响较大,其在拔节期~抽穗期均...  相似文献   
19.
为探究硅在燕麦抗秆锈病过程中的生理功能,以易感秆锈病的燕麦品种‘坝莜1号’为试验材料,采用盆栽方法,分别浇灌含不同浓度(0、0.5、1.0、1.5、2.0、2.5和3.0mmol/L)K2SiO3的营养液,测定燕麦幼苗秆锈病抗性,叶片光合性能,抗氧化酶活性及渗透调节物质的含量等指标。结果表明:接种秆锈菌条件下,施用1.5mmol/L K2SiO3可显著提高燕麦幼苗抗秆锈病能力及叶片的光合特性、抗氧化酶活性和渗透调节能力。与 0 mmol/L(CK)相比,燕麦幼苗干和鲜重分别提高90.91%和74.71%,叶片叶绿素含量提高18.67%,净光合速率(Pn)、蒸腾速率(Tr)、气孔导度(Gs)和胞间 CO2浓度(Ci)分别提高51.47%、285.71%、285.71%和27.78%,最大荧光(Fm)、光化学效率(Fv/Fm)和光...  相似文献   
20.
以位于内蒙古阴山北麓武川地区耕地为试验地点,对燕麦不同留茬高度进行粗糙度、风蚀量和吹蚀量的监测,比较燕麦不同留茬高度对土壤风蚀的影响.结果表明,与传统耕作相比,燕麦田留茬能有效增大地表粗糙度和降低近地风速;随着燕麦留茬高度的增加,地表粗糙度增大、风蚀量和吹蚀量降低.  相似文献   
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