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91.
牛的冻精稀释液是精液冷冻保存和人工授精最关键的环节。本文进行了两个方面的试验研究,一是把各个地区生产实践中应用的不同冷冻稀释液配方,进行综合筛选和比较;二是对没有条件冷冻精子的养殖场进行精子保鲜的稀释液配方进行综合筛选和比较。结果显示,当冷冻保存精液时,选择配方2为最佳配方;常温保存时选择配方2、3、4均可。  相似文献   
92.
93.
不同药剂防治玉米粗缩病试验结果表明,药剂拌种和喷雾防治对玉米粗缩病均有一定的防控效果,其中以70%锐胜可湿性拌种剂拌种+10%吡虫啉可湿性粉剂225 g/hm2对水225 kg于玉米四叶期前喷雾防治效果最好,防效达78.03%;其次为10%吡虫啉可湿性粉剂225 g/hm2+20%盐酸吗啉胍水悬浮剂375 g/hm2于玉米四叶期喷雾;防效可达75.95%。  相似文献   
94.
采用修正的Hedley磷素形态分级方法,研究了不同培肥处理对土壤各形态磷的影响。研究结果表明,施肥处理对土壤中各种磷素形态都有提高,但不同处理提高的幅度不同,其中,对活性态磷(H2O-P+NaH-CO3-P)的提高幅度依次为:无机肥+有机肥+菌肥>无机肥+菌肥>无机肥+有机肥+基质>无机肥+有机肥>无机肥>CK,对中等活性态磷(NaOH-P)的提高幅度依次为:无机肥+有机肥+菌肥>无机肥+有机肥>无机肥+菌肥>无机肥+有机肥+基质>无机肥>CK。无机肥+有机肥+菌肥处理与对照相比,对土壤的活性态磷和中等活性态磷分别提高了149.6%和73.3%。  相似文献   
95.
Nine trials were carried out on the induced propagation of pike perch in out‐of‐season as well as in the natural reproduction period. From January till May, periodically, 16–20 pairs were transported to the hatchery, and acclimated to 15–16°C. The following hormonal treatments were used to induce reproduction: carp pituitary homogenate (CP) and human chorionic gonadotropin (hCG) alone or in combination; gonadotrop‐releasing hormone ‘Ovurelin’ (D‐Phe6‐LH‐RH) alone or with metaclopramid (MTC); and ‘Ovopel’ [containing des‐Gly10‐(D‐Ala6)‐LH‐RH‐ethylamide and MTC]. The effects of daylight regime, water temperature and the length of the pre‐spawning conditioning period on the reproduction performance were determined. From the 130 hormonally treated pairs, 122 either spawned in tanks or were stripped. There were no differences in the ovulation rate between out‐of‐season (93%) and seasonal (91%) propagation. The developmental stage of the eggs correlated with the latency period, which significantly declined from January till April. The latency period was the shortest in fish treated with hCG and, secondly, with CP. The germinal vesicle migration did not proceed without hormonal treatment, although in some trials breeders were kept at the spawning temperature for 1–2 weeks. The results demonstrate that the pike perch can be successfully induced to spawn about 3 months earlier than its natural spawning season, which allows a significantly prolonged yearly supply of fry.  相似文献   
96.
The effectiveness of curing oranges and lemons at 33 degrees C for 65h followed by storage under ambient and cold-storage conditions was investigated. This treatment effectively reduced the incidence of Penicillium digitatum (Pers) Sacc and P italicum Wehmer decay on inoculated and naturally infected oranges and lemons stored at 20 degrees C for 7 days. However, it failed to control green and blue mould infections on fruits placed in long-term cold storage, except green mould on oranges, which was effectively controlled. Dipping fruits in a sodium carbonate solution (20 g litre(-1)) for 2.5 min following a curing treatment at 33 degrees C for 65 h satisfactorily reduced green and blue mould incidence during subsequent long-term storage at 4 degrees C on oranges and at 10 degrees C on lemons. The efficacy was greater on injured fruits inoculated after the combination of treatments was applied, achieving a 60-80% reduction in decay in comparison with the curing treatment alone in all cases. A significant reduction of blue mould was also observed on fruits inoculated both before the treatments and on those re-inoculated after the treatments, demonstrating both protectant and eradicant activity. Thus, combining curing at 33 degrees C for 65 h with sodium carbonate treatment effectively controlled these post-harvest diseases on artificially inoculated citrus fruits and protected against re-infection. With naturally inoculated lemons, curing followed by sodium carbonate significantly reduced both green and blue mould incidence, but was not superior to curing alone. With naturally infected oranges, curing significantly reduced blue mould, but decay was not reduced further when followed by sodium carbonate treatment.  相似文献   
97.
"根康健"处理进出境园林种苗携带的植物寄生线虫   总被引:1,自引:0,他引:1  
周弘  沈培垠 《植物检疫》2003,17(4):208-212
1999~2001年,对2年生感染根结线虫、双宫螺旋线虫的黄扬、冬青和榕树等17种苗木,5年生的景天等7种盆景的根部进行药剂处理。试验结果表明,使用“根康健”1:2倍液蘸根处理2h后,供试植物根上的外寄生性双宫螺旋线虫被全部杀死,36h后内寄生性根结线虫死亡率高达99%,25天后处理样中未检出任何活线虫。使用“根康健”1:4、1:6倍液进行药剂处理,25天后线虫死亡率分:到达87%~100%。“根康健”1:2倍液作为出入境观赏植物线虫处理剂,可以有效地杀死根组织内外的植物寄生线虫,满足苗木、盆景、花卉等的植物检疫要求。  相似文献   
98.
不同水分处理对小麦氮素和干物质积累与分配的影响   总被引:2,自引:0,他引:2  
为明确同一肥料水平下不同水分处理对小麦氮素和干物质积累与分配的影响,于2018-2019年在防雨棚条件下,以石麦26、藁优2018和冀麦418为材料,采用随机区组试验,设置不灌水(W1,0 mm)、起身水(W2,60 mm)、拔节水(W3,60 mm)、开花水(W4,60 mm)、起身水+开花水(W5,60 mm+60 mm)、拔节水+开花水(W6,60 mm+60 mm)共6个水分处理,分析了不同水分处理下小麦干物质和氮素积累与分配的特点。结果表明,小麦干物质积累量随灌水量的增加而增加。随着生育进程的推进,干物质积累量呈上升趋势,成熟期达到最大值;起身水显著增加拔节期干物重,开花期和成熟期不同处理间干物质积累量差异显著,成熟期W1处理下干物质积累量最小。开花后干物质积累对籽粒的贡献率因品种而异,冀麦418在W6处理下氮素利用效率和氮肥生产效率最高。W5和W6处理显著增加小麦籽粒产量、氮素吸收效率和氮肥生产效率,说明在小麦营养生长阶段水分正常供应的前提下开花期水分对小麦氮素吸收和向籽粒转运影响较大。W6处理为本试验条件下最佳的灌水处理。  相似文献   
99.
为研究不同均细化处理方式对桃果浆色泽的影响,本试验对新鲜桃原料进行打浆和超细粉碎(50 Hz)处理,对热烫后的桃原料进行打浆、胶体磨和湿法超细粉碎(18、26、34、42和50 Hz)处理,分析不同均细化处理对桃果浆表观色泽以及物质成分的影响.通过Pearson相关系数和逐步线性回归方程分析,进一步明确均细化处理过程中...  相似文献   
100.
Wild asparagus (Asparagus acutifolius L.) is a widespread species found in all the Mediterranean areas. The spears are highly valued by consumers and owing to its frugality, this species is a feasible new crop with high income potential, especially for Mediterranean marginal areas. Currently, the cultivation of this species is limited because of its low and erratic seed germination that makes difficult the production of seedlings for plant propagation. In this research, non-after-ripened (1 month-old) and after-ripened seeds (dry stored at room temperature for 13 months) were exposed for 30 days in the dark to three moist stratification treatments: cold (5 °C), warm (23 °C) or no stratification; subsequently they were soaked for 12 h in warm water (35 °C) or not soaked. The effect of these pre-germination treatments on three germination parameters (germination percentage, time to 50% of final germination – T50 – and germination pattern) was studied, as well as some possible seed dormancy forms involved therein. The 1-year dry storage period proved to be effective in after-ripened seeds by enhancing seed sensitivity to the subsequent pre-germination treatments. After-ripened seeds exhibited higher and more rapid germination compared to non-after-ripened seeds. Soaking, cold or warm moist stratification had similar single effect on non-after-ripened seeds (27% germination). With after-ripened seeds, only soaking or warm stratification were effective (47% germination) when singularly applied, while cold stratification did not improve germination. By combining stratification and soaking treatments, a higher germination for both non-after-ripened and after-ripened seed-lots was achieved. The highest germination was obtained when after-ripened seeds were stratified and soaked (76%), without any significant difference between cold or warm stratification. Single or combined application of moist stratification (regardless of the temperature used) and soaking resulted always in a faster germination compared to that of no-treated seeds and especially with after-ripened seeds (T50 = 6 days). A non-deep type 1 physiological dormancy can be hypothesized for the seeds of this species. Low stratification temperature induce secondary dormancy in after-ripened seeds that can be removed by soaking them at 35 °C for 12 h.  相似文献   
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