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毛竹蚧虫—蠕须盾蚧的观察研究 总被引:4,自引:0,他引:4
本文报导为害毛竹秆部的主要蚧虫——蠕须盾蚧。经多年来观察研究,在福建省尤溪、沙县、南平、建瓯、上杭等县市的毛竹林中常受该虫为害,严重者毛竹秆受害率达70%—90%。该虫一年发生2代,大量以成虫和少量以卵在雌介壳中越冬,5—6月和9—10月为为害的高峰期,而且世代重叠严重。其天敌发现有日本方头甲等多种;经药剂防治试验结果,以快灭磷、氧化乐果等农药,采用注射法或涂秆法效果显著。 相似文献
165.
应用实验种群生命表数据分析毛竹林本土优势种竹盲走螨和引进种胡瓜钝绥螨对毛竹4种害螨南京裂爪螨、竹裂爪螨、竹缺爪螨、竹刺瘿螨的控制能力。结果表明①胡瓜钝绥螨取食上述4种害螨的世代存活率分别为90.4%、77.55%、87.93%、81.63%,每雌总产卵量分别为38.12粒、45.77粒、35.59粒、30.26粒,而乡土优势种竹盲走螨取食上述4种害螨的世代存活率分别为95.23%、100%、87.7%、80.48%,每雌总产卵量分别为44.5、46.8、41.15、20.1粒;②竹盲走螨以南京裂爪螨为猎物时其内禀增长率(0.155)与引进种胡瓜钝绥螨(0.154)相近,均明显高于南京裂爪螨(0.1089);③竹盲走螨以竹裂爪螨为猎物其内禀增长率(0.152)与胡瓜钝绥螨(0.152)相同但明显低于竹裂爪螨(0.192);④竹盲走螨以竹缺爪螨为猎物时其内禀增长率为(0.148)明显低于引进种胡瓜钝绥螨(0.175)和其猎物(0.185);⑤竹盲走螨取食竹刺瘿螨易大量逃跑,雌螨产卵量低,引进种胡瓜钝绥螨取食竹刺瘿螨能正常生长发育,但是其内禀增长率(0.144)明显低于其取食上述其余3种害螨的内禀增长率,产卵量高于当地种竹盲走螨,并描述1998年以来每年5—6月助迁人工繁殖的胡瓜钝绥螨控制毛竹害螨蔓延的效果。 相似文献
166.
元江县桔小实蝇为害特点及防治试验 总被引:2,自引:0,他引:2
桔小实蝇在云南省元江县一年发生6代。每年有两个发生高峰期;4月下旬和7月初至8月初。该虫主要以幼虫取食芒果果实危害。采用果实套袋和甲基丁香酚诱杀雄虫可保护果实,降低桔小实蝇种群数量。 相似文献
167.
Casmara patrona is one of the main borer pests damaging Camellia oleifera in China. Few reports about this insect were published. The life history, biological characteristics and natural enemies of C. patrona were investigated through field survey and laboratory observation in this study. The results showed that C. patrona had one generation in one year or two years, and overwintered as 3rd-5th instar larva in Zhejiang Province. About 88 percent of larvae began to pupate in early May, and the rest kept feeding till the next year. The adults could be observed from early June to early July, and the peak of emergence occurred in late June. The adults began to oviposit in late June and terminated in early July. The eggs started hatching in early July, and then the larvae bored into the branch to feed. The entrance holes of the larvae distributed predominately in the middle of the eastern and southern part of C. oleifera tree. The larva had five instars, and there were 10-50 days when the larva did not feed between consecutive instars. 相似文献
169.
肉牛场生命周期估计及环境影响评价 总被引:1,自引:0,他引:1
试验采用生命周期估计(life cycle assessment,LCA)方法对江西高安某存栏1 800头的肉牛育肥场在整个育肥期间(7个月)的污染物排放量,以及污染物在全球变暖、环境酸化、富营养化、光化学臭氧合成方面对环境的影响进行了评估。系统边界包括化肥生产、农作物种植、饲料运输、肉牛生产和粪便处理。结果表明:温室气体排放量为(以CO2当量计)为11 908t,环境酸化气体排放量(以SO2当量计)为84.6t,富营养化气体排放量为(以PO43-当量计)为14.4t,光化学臭氧合成问题气体排放量为(以C2H4当量计)为1.68t。其中饲料运输主要影响全球变暖(占总排放量的49.8%)和光化学臭氧合成问题(占总排放量的54.1%),而粪便处理主要影响环境酸化(占总排放量的70.1%)和富营养化(占总排放量的76.4%),肉牛生产对环境的影响主要是全球变暖(占总排放量的18.1%)和光化学臭氧合成问题(占总排放量的30.9%)。因此,可考虑通过降低运输距离,改善饲料配方、粪便处理方式等降低污染物排放量。 相似文献
170.
The response to azinphos-methyl of different life-stages of the codling moth Cydia pomonella (L.) was studied. A similarity in response to azinphos-methyl (LC(50), LC(90)) was observed in neonate larvae obtained from the first and second generations of field populations. Mortality rates for neonate larvae of a field population cross-bred with a laboratory colony were lower (by a factor of 1.2-2.2) in comparison with field neonate larvae. The mortality rate of larvae from a laboratory colony exposed to artificial diet containing azinphos-methyl gradually decreased at older instars. The mortality rates of fifth-instar larvae were remarkably low when exposed to artificial diet mixed with azinphos-methyl or when topically treated with the insecticide. One- to three-day-old females were more sensitive than males of the same age, whereas the opposite was observed in 14-to 17-day-old adults. Mortality rates of 14- to 17-day-old adults were higher than those under 10 days old. No significant difference in sensitivity to the organophosphorus compound was noticed between the sexes of 7- to 10-day-old adults. Neonate larvae of the codling moth can serve as a target life-stage for various groups of pesticides, and the importance of using such a stage as a standardized methodology for monitoring resistance in the codling moth is discussed. 相似文献