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1.
旨在满足马铃薯生产中茬口衔接、机械化生产技术应用、不利气候下稳产等对马铃薯出苗早、齐、壮的需求,以‘费乌瑞它’为供试品种,用基于有益活菌或工程菌提取物的5种生物制剂进行种薯处理,对多重性状进行了对比分析。5种生物制剂较常规化学制剂,均能够不同程度地促进种薯萌芽和芽根同生,出苗期提前2~7天,播种后49天的出苗率提高3.33%~17.78%。其中,表现最好的为酵母核苷酸衍生物和VDAL,种薯萌发和生根均显著高于对照。霜冻后,生物剂拌种处理在恢复前期促进植株生长,由此促进恢复后期的块茎发育,较常规化学处理增产8.39%~24.03%,体现了不同程度的保产效果。多马道黑、酵母核苷酸衍生物、根肽和VDAL体现出较好的保产效果,可作为种薯处理剂投入马铃薯生产。  相似文献   
2.
M. Fladung 《Plant Breeding》1993,111(3):242-245
The iaaL gene of Pseudomonas syringae subsp. savastanoi encodes an indoleacetic acid-lysine synthetase which conjugates free indoleacetic acid (IAA) with lysine. lAA-lys is biologically less active than free IAA. The iaaL coding region was expressed under the control of the cauliflower mosaic virus 35S promoter and transgenic potato plants were produced (Spena et al. 1991). 35S iaaL potato plants are characterized by increased internodal length and epinastic bending of older leaves. In three greenhouse experiments with plants grown in pots of different size and in two growth chamber experiments tuber number increased in iaaL transgenic plants compared to untransformed and vector-transformed controls of the same genotype. The increase in tuber numbers observed under controlled conditions was reflected in tuber yield which increased in the pot grown transgenics.  相似文献   
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The loss of final tuber weight of Eleocharis kuroguwai Ohwi by shading during the early tuber formation period (TFP) is overcome by exposure to unshaded daylight thereafter (late TFP). In the present study, the growth parameters that contribute to the dry matter increase (DMI) per day of tubers in the late TFP were examined. DMI of the tuber during the late TFP was determined by that of the whole plant and the ratio of the DMI of the tuber to that of the whole plant during this period. The ratio of the DMI of the tuber to that of the whole plant during the late TFP was significantly correlated with the DMI of the whole plant during the first 14 days of the late TFP. During the late TFP after the exposure to unshaded daylight, DMI of the whole plant correlated with the surface area of the stem (SAS) and net assimilation ratio (NAR), and the SAS correlated with the stem dry weight (DW) and specific stem-surface area (SSA). SSA negatively influenced NAR, but NAR was increased by unshading. During the late TFP after shading, the effect of the decrease of the stem DW due to shading on the DMI of the whole plant was mitigated by the large SAS and high NAR. These results indicate that the growth parameters that contribute to the DMI of tuber during the late TFP after exposure to unshaded daylight are SAS and NAR just after unshading, and SSA during this period.  相似文献   
5.
选取中国主栽的食用型甘薯品种龙薯9号、红香蕉、泰中6号、苏薯8号、遗字138和北京553进行大田试验,研究不同产量潜力甘薯品种光合产物的生产、运转及其与块根产量的关系。结果表明,高产品种整个生育期干物质积累快,光合产物向块根输送多,同化物在块根中的分配率较高,而且高产品种的标记叶合成的光合产物能够较多地运出。因此,叶片光合作用形成的光合产物能够及时地往外运输,是高产甘薯品种高产的重要保证。高产品种具有较高的经济系数。  相似文献   
6.
为筛选菊芋块茎DNA提取的适宜生育时期,以“青芋1号”菊芋品种为试材,用改良CTAB法对不同发育时期菊芋块茎DNA进行提取,经琼脂糖凝胶电泳及全波长分光光度计检测总DNA的纯度、浓度及质量,选用4条ISSR引物进行PCR验证.结果表明:不同发育时期提取菊芋块茎DNA效果较好,DNA浓度呈现单峰曲线变化,峰值出现在第9周,与琼脂糖凝胶电泳检测呈现的亮度结果一致,PCR验证结果显示,提取的DNA能够满足后续相关分子生物学的要求.  相似文献   
7.
A 3-year field study examined the effects of 1,3-dichloropropene or oxamyl on tuber yields in four early- and five late-maturing potato cultivars. The nematicide treatments increased total tuber yield by ≈ 12% for early-maturing cultivars, but by less than 2% for the late-maturing cultivars. The treatments reduced the numbers of root lesion nematodes (primarily Pratylenchus penetrans ), which were the dominant plant parasitic nematodes at the site. Covariance analysis indicated that treatment effects on total tuber yield were no longer significant after adjusting for root lesion nematodes in soil at harvest, confirming that these nematodes had a direct effect on the host. As expected, there were significant inverse relationships ( P  = 0·05) between total tuber yields and numbers of root lesion nematodes in soil and in roots. However, the application of nematicides in late-maturing cultivars was found to be of no practical value. Crop production systems designed to reduce or optimize pesticide applications can form one criterion in the development of more environmentally sensitive management strategies. The merit of utilizing chemicals for root lesion nematode control are considered with regard to cultivar maturity.  相似文献   
8.
马铃薯纺锤块茎类病毒的检测和防治   总被引:5,自引:1,他引:5  
马铃薯纺锤块茎类病毒病(potato spindle tuber viroid,PSTVd)是一种严重为害马铃薯生产的病害,降低产量20%—30%。防治的主要措施是应用无类病毒的种薯。由于目前还没有脱掉类病毒的有效措施,只能从未被饱和侵染的群体中鉴定筛选出未被侵染的个体,再脱掉其它病毒,作为核心繁殖材料。1987年以来,利用自制的电泳设备,以往复聚丙烯酰胺凝胶电泳法(return-polyacrylamide gel electrophoresis,R-PAGE)检测类病毒,筛选出未感病的个体,再用茎尖组织培养法脱掉其它病毒。经用马铃薯卷叶病毒等8种病毒酶标抗体鉴定筛选,获得既无类病毒也无主要马铃薯病毒的克新1、2、3和4号等主栽马铃薯品种的核心种。并已提供给省内外的良种场繁殖推广。1989和1990年抽样检测克山良种场繁殖的原种、一级和二级良种,未检测到类病毒。  相似文献   
9.
The purpose of this study was to establish the normal percutaneous ultrasonographic appearance of anatomic structures within the equine sacroiliac region. Percutaneous ultrasonography was performed in a cranial-to-caudal direction in 10 normal adult live horses. The following structures were examined in detail: supraspinous ligament, lumbar and sacral spinous processes, thoracolumbar fascia and its caudal extension, tubera sacralia, ilial wings, dorsal and lateral portions of the dorsal sacroiliac ligaments, lateral part of the sacrum, and the lateral sacral crest. After ultrasonography, all animals were euthanized and detailed dissection of the lumbosacropelvic region was performed in six horses. Four lumbosacropelvic specimens were frozen and sectioned transversely for evaluation of cross-sectional anatomy. Gross anatomic findings were correlated with ante-mortem ultrasonographic images. On percutaneous ultrasonography, all horses had tubera sacralia with a mild-to-moderate roughened surface with occasional irregular hyperechoic mineralizations located within the apophyseal cartilage of younger horses. At the level of the tuber sacrale the caudal extension of the thoracolumbar fascia joined the dorsal portion of the dorsal sacroiliac ligament and assumed two different configurations relative to the dorsal portion of the dorsal sacroiliac ligament, with the predominant configuration of the thoracolumbar fascia located medial to the dorsal portion of the dorsal sacroiliac ligament. The less frequently encountered configuration had the thoracolumbar fascia positioned dorsal to the dorsal portion of the dorsal sacroiliac ligament. Caudal to the tuber sacrale the dorsal portion of the dorsal sacroiliac ligament and thoracolumbar fascia consolidated to form a single, fused structure with a common insertion on the sacral spinous processes. A large variability in linear fiber pattern, echogenicity (small focal hypoechoic areas), ligament height, and cross-sectional measurements was identified in the fused dorsal portion of the dorsal sacroiliac ligament and thoracolumbar fascia of normal horses. Diagnosing mild-to-moderate desmitis of the fused dorsal portion of the dorsal sacroiliac ligament and thoracolumbar fascia based solely on ultrasonography may therefore be difficult. To correlate ultrasonography with histology, samples of a fused dorsal portion of the dorsal sacroiliac ligament and thoracolumbar fascia with bilateral hypoechoic lesions were submitted for histology and revealed diffuse mild-to-moderate loss of fiber density, multifocal fibrocyte degeneration, and cartilagenous metaplasia with multifocal, mild myofiber mineralization, which was compatible with age-related changes. As controls, sections of ultrasonographically normal fused dorsal portion of the dorsal sacroiliac ligament and thoracolumbar fascia from three horses demonstrated similar but milder histologic findings, which were considered normal.  相似文献   
10.
A rapid warming of 2.8–5.3 °C by the end of this century is expected in South Korea. Considering the current temperature during the spring potato growing season (emergence to harvest; ca. 18 °C), which is near the upper limit of the optimum temperature for potato yield, the anticipated warming will adversely affect potato production in South Korea. The present study assessed the impact of high temperature on the marketable tuber yield and related traits of cv. Superior (which makes up 71% of the annual potato production in South Korea) in four temperature-controlled plastic houses and an outdoor field (37.27°N, 126.99°E) during 2015–2016. The target temperatures of the four plastic houses were set to ambient (AT), AT+1.5 °C, AT+3.0 °C, and AT+5.0 °C. The marketable tuber yield was significantly reduced by 11% per 1 °C increase over a temperature range of 19.1–27.7 °C. The negative impact of high temperature was associated not only with the yield loss of total tubers, which was mostly explained by the slower tuber bulking rate, but also the reduced marketable tuber ratio under temperatures above 23 °C, which was mainly attributed to the reduced number of marketable tubers (r = 0.79***). Under moderate temperatures below 23 °C, the source limited the number of marketable tubers without reducing the marketable tuber ratio. In contrast, the number of marketable tubers was limited by the marketable tuber set at the early growth stage rather than the source under the higher temperatures, which resulted in the reduction in the marketable tuber ratio below 56%. These results suggest that the objectives of breeding and agronomic management for adapting to the rapid warming in South Korea should include maintaining the ability to form tubers at the early growth stage under high temperatures, as well as the photosynthetic capacity and sink strength of the tubers.  相似文献   
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