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以不套袋鸭梨为研究对象,采用不同浓度水杨酸处理,以水浸果实为对照,对鸭梨采后褐变指数、多酚氧化酶、酚类物质以及保护酶的活性进行测定。以有效地抑制采后鸭梨果实的黑心病,调控鸭梨果实成熟衰老的进程、改善果实品质和贮藏性能提供理论依据。结果表明:0.002、0.020、0.200mmol水杨酸处理鸭梨果实后有效减轻了腐烂和褐变的发生,其中0.200mmol水杨酸处理能显著抑制鸭梨果心中PPO活性和酚类物质的合成,并且对鸭梨果心中SOD、POD保护酶的活性促进效果最显著;而0.002mmol水杨酸处理对鸭梨果心中MDA的含量有显著抑制作用。表明水杨酸处理可以延缓果实衰老,明显抑制鸭梨果心褐变的发生,有利于延长果实的贮藏期。 相似文献
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利用2009年1月~2010年12月河间自动气象站和人工观测的气压、气温、相对湿度资料,对其资料进行统计对比分析并探讨两者差值的形成原因。结果表明,自动站与人工观测值月平均气压差值为-0.2~0.3 hPa,月平均最高气压差值为0~0.5 hPa,月平均最低气压差值为-0.4~0.3 hPa,月极端最高气压差值为-0.2~0.9 hPa,月极端最低气压差值为-0.6~0.6 hPa;月平均气温差值为0~0.2℃,月平均最高气温差值为0~0.2℃,月平均最低气温差值为-0.1~0.4℃,月极端最高气温差值为-0.2~0.6℃,月极端最低气温差值为-0.3~0.6℃;月平均相对湿度差值为-3%~3%,月最小相对湿度差值为-9%~3%。气象要素对比观测差值产生的原因主要有观测仪器和观测原理的差异、数据采集时间与方法不同、感应器安装位置及所处环境不同以及人工干预与观测误差等主观因素。 相似文献
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JiaHao WANG YaQian DUAN LanChun NIE LiYan SONG WenSheng ZHAO SiYu FANG JiaTeng ZHAO 《中国农业科学》2019,52(24):4582-4591
【Objective】The aim of this study was to identify the typical indices of fruit quality and high quality materials of ‘Yangjiaocui’ melons to provide reference and basis for melon quality evaluation and breeding. 【Method】Eighteen indices, including economic trait and flesh quality of fruits from 6 cultivars and 26 high-generation inbred lines of ‘Yangjiaocui’ melons were determined. Based on factor analysis, stepwise regression, correlation analysis and two-dimension ordination map, the typical indices of fruit quality and high quality materials were identified. 【Result】 Among the 18 indices, single fruit mass, hardness, vitamin C (VC) content, titratable acid content, sugar-acid ratio and solid acid ratio showed greater variability, and the variation coefficients were more than 20%. However, the variability of fruit transverse diameter, flesh thickness rate and pH were relatively lower and the variation coefficients were less than 10%. Three common factors were extracted from economic trait indices with 87.71% cumulative variance contribution rate and the explanatory indices were fruit longitudinal diameter, fruit transverse diameter, fruit shape index, fruit cavity longitudinal diameter, fruit cavity transverse diameter and flesh thickness rate. From quality indices, 4 common factors were extracted with 90.03% cumulative variance contribution rate and the explanatory indices were VC content, hardness, total soluble solids content, total sugar content, titratable acid content, sugar-acid ratio and solid-acid ratio. Based on the comprehensive analysis of these selected 6 economic trait indices and 7 flesh quality indices, 5 common factors were extracted with 87.35% cumulative variance contribution rate. According to the correlation among the indices and the principle of simplicity and ease of use and avoidance of overlapping information, 5 indices, including fruit longitudinal diameter, flesh thickness rate, hardness, total sugar content and titratable acid content, could be used as typical indices to evaluate the fruit quality of ‘Yangjiaocui’ melons. The comprehensive quality score of all materials were ranked depended on scores and variance contribution rate of the above 5 common factor and two-dimension ordination map. Finally, 10 materials were selected as high quality materials. 【Conclusion】 Fruit longitudinal diameter, flesh thickness rate, hardness, total sugar content and titratable acid content could be used as typical indices to evaluate fruit quality of ‘Yangjiaocui’ melons. Inbred lines 25, 24, 22, 21, 8, 1, 17, 18, 20 and 23 were high quality materials. 相似文献
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昆虫病原真菌绿僵菌对地下害虫防治具有良好应用前景,而大量释放绿僵菌可能引起土著微生物群落变化,从而影响其植物保护的综合效果。本文研究了花生播种期施用绿僵菌后,在根际和根围土壤中绿僵菌自身种群及土著细菌、真菌和放线菌种群的消长和群落结构变化。结果表明,绿僵菌种群在30 d内快速下降,之后降速减缓,以低密度持续存活。随花生生长,土壤微生物自身有消长过程,施用绿僵菌对放线菌影响最大、真菌其次、细菌最小,在根际的影响大于在根围的影响。分别地,绿僵菌处理对根际和根围细菌、根围真菌无显著影响;使根际真菌种群初期的下降速度减缓,到达谷底时间由15 d推迟到30 d,但回升速度加快,达峰顶由60 d提前到45 d,峰值降低1/3;绿僵菌明显抑制了根际放线菌种群,使其消长变化周期与对照完全相反,且45 d时回落至低点后不再回升;绿僵菌减缓了根围放线菌种群下降,使达谷底时间由30 d推迟到45 d,且回升幅度减小。土壤微生物群落结构在施菌后15~30 d的幼苗至初花期有明显变化,细菌种群总体占比显著下降,但与对照相比,施菌后的根际细菌占比提高,真菌占比下降,放线菌占比显著地先抑后扬。在根围的变化相对较小。45 d即盛花期后,三类微生物结构逐渐恢复趋近原来状态。 相似文献
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