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21.
玉米抗旱性鉴定指标的研究   总被引:54,自引:4,他引:54  
研究指出抗旱系数及脯氨酸含量、叶水势、丙二醛含量、相对电导率、蒸腾速率、叶面积和叶形态变化等指标均可作为玉米抗旱性鉴定指标的良好参数 ,并以抗旱系数为主要参数计算了各生理生化指标的相关系数 ,用以衡量这些指标在玉米抗旱性鉴定及综合评价的重要性。  相似文献   
22.
[目的]为引种和开发抗旱性芳香植物提供一定的理论依据。[方法]以多种芳香植物为研究对象,探讨植物受到干旱后植株叶片生理指标与形态指标的变化。[结果]在干旱胁迫下,几种芳香植物的生长受到抑制,植株叶片含水量下降,脯氨酸含量升高。复水后,它们都能恢复良好的生长状态。[结论]在不同种类之间,薄荷和丁香罗勒抗旱性最强,缬草抗旱性最弱。  相似文献   
23.
In an attempt to find a suitable alternative to the otherwise perilous chemical control strategy of disease management, the amino acid proline was evaluated for its efficiency to elicit resistance in pearl millet (Pennisetum glaucum (L.) R. Br.) against downy mildew disease caused bySclerospora graminicola (Sacc.) Schroet both under greenhouse and field conditions. Proline treatment to seeds at 50 mM concentration for 3 h, significantly enhanced the seed germination and seedling vigor of pearl millet in comparison with the control. The same concentration and duration of seed treatment protected the pearl millet plants from downy mildew by offering 58% protection under greenhouse and 67% protection under field conditions. Studies revealed that 3 days were required for proline-treated plants to develop resistance, which was systemic and was sustained throughout the life of the plants. Apart from disease protection, proline was also found effective in enhancing vegetative and reproductive growth of the plants, as evidenced by the increase in height, fresh weight, leaf area, tillering capacity, 1000-seed weight and grain yield in comparison with the control plants. http://www.phytoparasitica.org posting Oct. 3, 2004.  相似文献   
24.
盐胁迫下水稻发芽特性和幼苗耐盐生理基础   总被引:4,自引:3,他引:1  
选用中花11号和265号水稻品种进行发芽和苗期耐盐试验。结果表明,随着NaCl浓度增加,种子发芽的时间推迟、发芽过程延长、发芽率降低;不同浓度的NaCl处理抑制幼苗生长,与根系相比对苗生长的影响更大;不同浓度的NaCl处理对265号水稻品种苗期生理生化指标有影响,随着NaCl处理浓度的增加,脯氨酸含量直线性上升,过氧化物酶的含量呈下降趋势。  相似文献   
25.
香木莲对短时低温胁迫处理的生理生态响应   总被引:4,自引:0,他引:4  
通过测定木兰科植物香木莲在人为短时低温处理下的一些生理生化指标的变化情况,可以分析香木莲苗木的抗性生理情况,以期对香木莲的抗寒性进行评价.实验结果表明,香木莲的叶片在经短时低温处理后,其脯氨酸含量、丙二醛含量及相对电导率均表现为不同程度的上升.而叶片的叶绿素荧光指数的变化则表现为随处理时间的延长,叶片的原初荧光(Fo)上升,其光化学效率(Fv/Fm)及可变荧光/原初荧光比率(Fv/Fo)则表现为随处理时间的延长而降低.这表明,短时低温处理对叶片的叶绿体光系统的潜在活性及量子传递效率造成了一定的影响,结合生理生化指标的变化,可以部分解释香木莲抗寒机制.  相似文献   
26.
建立了高效液相色谱一电喷雾串联质谱法直接测定蜂蜜中脯氨酸的方法。蜂蜜样品用去离子水溶解后,过0.45μm水相微孔滤膜,高效液相色谱一电喷雾串联质谱进行分析检测。以Phenomenex C18(100mmx4.6mmx2.6μm)色谱柱为分析柱,乙腈和0.1%(v/v)甲酸-5mmol/L乙酸铵水溶液为流动相进行梯度洗脱,在电喷雾正离子多反应监测模式下进行检测,外标法定量。通过加标验证,该方法检测低限可达25mg/kg,脯氨酸在0.5~10.0μg/mL浓度范围内线性关系良好,相关系数大于0.99。在25、50和100mg/kg三个加标水平下,蜂蜜中脯氨酸平均回收率为83.7~109.6%,相对标准偏差(RSD)为2.4~10.9%。该方法样品处理简单、快速,结果准确,灵敏度高,可以作为日常蜂蜜中脯氨酸的检测方法。  相似文献   
27.
为研究干旱胁迫下小麦幼苗蛋白质和脯氨酸含量变化,进而探明不同品种小麦抗旱性差异,采用15% PEG-6000渗透胁迫,检测20个小麦品种幼苗蛋白质和脯氨酸含量.结果表明,渗透胁迫下,不同品种小麦幼苗蛋白质含量对照组均高于15% PEG处理组,品种间蛋白质含量变化率差异较大;不同品种小麦幼苗处理组脯氨酸含量均高于对照组,品种间脯氨酸含量变化率差异也较大;不同品种间处理组与对照组小麦幼苗蛋白质、脯氨酸含量差异均极显著;20个小麦品种中金麦8号、淮麦21和淮麦22具有较强的抗旱性.  相似文献   
28.
Prolific and rapid in vitro plant organogenesis via direct regeneration has been obtained from axenic seedling-derived petiole and leaf explants of Ficus religiosa in Murashige and Skoog (MS) medium containing different concentrations of cytokinins in combination with indole-3-butyric acid (IBA). MS medium with 1.5 mg/l 6-benzylaminopurine plus 0.15 mg/l IBA produced the highest shoot induction frequency with an average of 6.26 and 10.13 shoots per leaf and petiole explants, respectively. After 4 weeks, the highest root formation frequency (96.7%), root number (5.73), and root length (4.76 cm) were with MS medium containing 2.0 mg/l IBA plus 0.1 mg/l α-naphthalene acetic acid. In addition, the effect of four sodium nitroprusside (SNP) treatments on acclimatization was also studied. Highest morphological traits such as survival rates, fresh and dry root weights as well as antioxidant enzymatic activities such as superoxide dismutase, peroxidase, and catalase was achieved with 125 ppm SNP. The α-amino acid, proline, content was highest with this treatment while the highest H2O2 (hydrogen peroxide) was in the controls. This study introduces a cost-effective, prolific, and efficient in vitro multiplication system to supply pharmaceutical and ornamental needs. It is the first report of an in vitro organogenesis protocol for F. religiosa by direct regeneration through axenic seedling-derived petiole and leaf explants, which can be efficiently employed for the utilization of active biomolecules.  相似文献   
29.
Salinity is a major abiotic stress affecting plant growth and productivity. Considerable genetic variation is present in rice in response to salt stress, with higher sensitivity during early seedling and reproductive stage. In this study, physiological changes in leaves and developing panicles of rice genotypes(IR686, Sadri, Rc222, CSR28, IR670 and Pokkali) contrasting in salt tolerance at the reproductive stage were evaluated in greenhouse experiment under salt stress. The results showed that IR670 and the tolerant-check Pokkali maintained lower Na~+/K~+ ratio, less reduction in chlorophyll concentration, lower malondialdehyde(MDA) production, higher concentrations of reduced ascorbate(reduced AsA), higher proline accumulation and lower percentage reduction in pollen viability than the salt-sensitive genotypes under salt stress. The higher concentration of reduced AsA suggests an efficient ROS-scavenging system. Physiological measurements and pollen viability analysis revealed that Sadri(moderately tolerant at the seedling stage) is sensitive to salt stress at the flowering stage. The findings will be useful in breeding salt tolerant varieties at both seedling and reproductive stages by selecting appropriate genotypes and phenotypes.  相似文献   
30.
以黄瓜幼苗为材料,进行不同浓度的铅处理,研究其叶片丙二醛、脯氨酸和可溶性总糖含量的变化情况。研究结果表明,黄瓜幼苗叶片丙二醛(MDA)含量与铅浓度呈正相关,梯度Pb2 胁迫造成了幼苗叶片脯氨酸的含量逐渐增多,可溶性总糖含量与对照相比呈先增加后减少的趋势。  相似文献   
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