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951.
该文研究了花粉蒙导、植物激素和胚培养对梅花种间杂交的作用.结果表明,花粉蒙导是克服梅花与其它李属植物种间杂交不亲和性的有效方法.在花期和幼果阶段用GA144.35μmol连续处理,可将杂交结实率从1.4%提高到2.8%.通过MS附加IAA、6-BA或KT培养基的胚培养,建立了几个杂种无性系.再生植株在田间生长良好,尚需进一步鉴定  相似文献   
952.
杂交稻制种上父本应用旱土耐寒育秧的异交增产机理初探   总被引:1,自引:1,他引:0  
朱新明 《杂交水稻》1997,12(3):13-15
初步探索了父本应用旱土耐寒育秧所产生的异交增产效果。认为其异交增产机理主要是由于增加了单位面积的产粉密度,其次是父本的供粉状态得到改善,而导致母本结实率提高的结果  相似文献   
953.
Summary Pollinating apple cultivars twice with compatible pollen at an interval of one or two days produced about twice as many seeds per pollinated flower as a single pollination. With the aid of scab- or mildew resistant marker pollen, it could be shown that the second pollen formed on average twice as many seeds as the first. The first pollen appears to pave the way-partly at its own cost-for the second and was therefore called pioneer pollen.  相似文献   
954.
杂交水稻繁制种隔离距离的研究   总被引:4,自引:0,他引:4  
1986—1987年以不育系做受体,采用盆栽方法于开花前将受体移至粉源东南西北四个方向,每隔25米设一档次,最远距粉源275米,腊熟期统计受体的结实率。根据我们对玉米、高粱种子田隔离的研究,从定量水平求得的有无父本花粉竞争条件下污染结实率差异的统计量得知,无花粉竞争条件下的数值是有花粉竞争的三倍。本试验(无父本花粉竞争)在隔离25米,两年四个方向的平均结实率应为4.44%÷3=1.40%;隔离75米为1.20%÷3=0.40%,纯度分别可达98.52%和99.60%,均已超过国家一级杂交种纯度97%和一级亲本种纯度99.5%的标准。故此,认为国家现行隔离距离丘陵区50米以上,平湖区100米以上应更正为制种田25米以上,亲本繁殖田75米以上。  相似文献   
955.
Freeze preservation of gladiolus pollen   总被引:4,自引:0,他引:4  
Viability and fertility profiles of cryopreserved gladiolus pollen from 7 cultivars have shown that it is possible to use cryogenic methods for conservation and management of the haploid gene pool in this species. There was no decline in pollen viability (in vitro) levels after 1 and 10 years of cryogenic storage. Field pollinations with cryogenic stored pollen induced capsule and seed set in varying capacities. Long-term cryogenic storage of gladiolus pollen could enhance breeding efficiency through better management of the haploid gene pool resources. Pollen parents could be made available throughout the breeding programme, ensuring guaranteed supply at the time of peak stigma receptivity. A pollen cryobank facility established for this species would increase genetic diversity conservation at the haploid stage.IIHR Contribution No. 112/93  相似文献   
956.
Drought tolerance in sorghum by pollen selection using osmotic stress   总被引:2,自引:0,他引:2  
A pollen selection study for drought tolerance using Poly Ethylene Glycol (PEG) as a selective agent was conducted in sorghum. Ten genotypes of sorghum suitable for post rainy season were crossed to cytoplasmic male sterile line 104A and three genotypes to 116A producing 13 hybrids. Two sets of 13 hybrids with and without pollen selection were produced. PEG at 36 per cent was applied to stigma and stylar tissue one hour before pollination for pollen selection (selective fertilization) and no treatment for control (nonselective fertilization). Hybrids thus produced through selective and non-selective fertilization were tested in moisture stress environment during post rainy season. The hybrids obtained through selective fertilization produced significantly higher mean grain yield compared to hybrids obtained through non-selective fertilization. The results indicate that selective fertilization through in vivo pollen selection using PEG as selective agent was effective in improving moisture stress tolerance of the progeny in sorghum genotypes studied. Further, the pollen selection also had influence on plant height, panicle length, panicle width, panicle weight and grain mass. Thus,the pollen selection had a significant effect on grain yield through its components and developmentally related traits. Pollen selection for osmoticstress tolerance in sorghum influences the growth and vigour of the plants resulting in superior progeny in moisture stress environment. The analysis of individual crosses indicated that pollen genotype selection was able to favour performance of the progeny. However, the pollen selection had positive effect in majority of the hybrids and the study demonstrates the transmission of the selected trait from pollen generation to progeny. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   
957.
T. R. Tarn  J. G. Hawkes 《Euphytica》1986,35(1):293-302
Summary The South American wild potato species Solanum commersonii Dun. exists as two subspecies, subsp. commersonii and subsp. malmeanum (Bitter) Hawkes and Hjerting, and as both diploid and triploid cytotypes. The two subspecies were completely cross fertile but there were reciprocal differences in the number of seeds set per berry and the mean seed weight. Crosses between diploids and colchicine-induced autotetraploids yielded only a few seeds per berry, but 16 of the 18 germinated seeds were triploid or nearly so. Such a high proportion of triploids is unusual for such crosses in potatoes. Some triploids has a high percentage of stainable pollen. The origin of naturally occurring triploids is discussed in the context of 2n gametes, a triploid block, and endosperm balance numbers.  相似文献   
958.
沙棘育种方法--沙棘花粉生活力研究   总被引:2,自引:0,他引:2  
本文研究了沙棘花的结构、开花所需的条件、花粉的收集和贮藏方法及不同的贮存条件下,保持沙棘花粉生活力的时间长短,通过降低花粉水分含量和低温冷藏以及玻璃器具密封等保存措施,可以达到长时间储存沙棘花粉的目的。同时对沙棘单交的技术进行了介绍。  相似文献   
959.
蔬菜花粉壁非光滑表面微结构及其仿生脱附   总被引:2,自引:0,他引:2  
采用电镜扫描SEM对22个科62个属111种蔬菜植物孢粉壁表面结构进行观察分析,选出其中典型8个科10个属11个种的非光滑结构并进行特征描述;对蔬菜花粉壁非光滑微表面具有的脱附功能进行分析,不仅丰富了生物脱附理论,同时可为发展仿生绿色清洁技术提供理论依据及有益信息。  相似文献   
960.
The present study is about some aspects of the reproduction physiology of twenty apricot clones ( Prunus armeniaca L.) grown in Abarán (Murcia, Spain). Self incompatibility of these clones was determined not only in field conditions in terms of the fruit set by means of self fertilization and free pollination, but also in laboratory conditions, by means of fluorescence microscopy of pollen germination on the stigma and of the growth of the pollen tube towards the egg. The only clone with signs of self incompatibility was ‘Moniquí Azaraque’. The clone with the lowest fertilization time was ‘Chicanos Archena’. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   
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