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41.
42.
An experiment was conducted in 2001 at Holetta and Kulumsa, Ethiopia, to study the extent and pattern of genetic diversity in Ethiopian field pea (Pisum sativum L.) landraces. One hundred forty-eight germplasm accessions were grown in an alpha lattice design with 2 replications. Data on 12 traits were collected and analyzed. Differences among the accessions were significant for most of the traits (except number of seeds/ pod) at each location even though differences pooled over location were mostly non-significant. The accessions were grouped into five clusters of different sizes. Accessions from the southern part of the country (Arsi) distributed overall clusters while those from the northern half (North and South Wello, North Gonder and North Shewa) fell into clusters C1 to C3. Cumulative effects of a number of characters dictated differentiation of the accessions into clusters. There was no definite relationship between geographic diversity and genetic diversity as overlapping was encountered in clustering pattern among accessions from different parts of the country. Accessions from different regions might have similar genetic background and those from the same origin might also have different genetic background. Therefore, geographic diversity should not necessarily be used as an index of genetic diversity and parental selection should be based on a systematic study of genetic diversity in a specific population. Genetic distances among most of the clusters were significant that crosses between parents selected out of them are expected to generate desirable genetic recombination. Selection should also consider the special advantages of each cluster and each accession within a cluster. Future germplasm collection, conservation and breeding efforts should focus not only on inter-regional diversity but also on intra-regional diversity.  相似文献   
43.
不同处理对豌豆芽苗菜生长和产量的影响   总被引:8,自引:0,他引:8  
 研究了浸种时间、播种密度、温度、播种到采收时间等因素对豌豆芽苗菜生长和产量的影响。结果表明:在20~25 ℃下播种,第8 d采收,豌豆芽苗菜的产量最高;播种密度为2.4 kg/m2时,生物产量和生物产率都比较理想。  相似文献   
44.
本文规定漳州甜豌豆产品符合“NY5078-2005《无公害食品豆类蔬菜》”与“GB2763-2005(食品中农药最大残留限量》”标准要求,以及符合出口日本、美国、欧盟等国家或地区标准要求的生产基地选择,良种选用,播种,田间管理,病虫害防治,采收,监测及建立生产档案等质量安全生产技术规程。  相似文献   
45.
双垄全膜马铃薯套种豌豆对马铃薯生育期及病害的影响   总被引:1,自引:0,他引:1  
在双垄全膜马铃薯套种针叶豌豆的栽培模式下,研究了其对马铃薯的生育期及病害的影响。结果表明,马铃薯在双垄全膜栽培条件下出苗、现蕾、开花及成熟都较露地有所提前。在病害方面,覆膜使马铃薯早疫病的发生加重,但对晚疫病的发生有很好的抑制作用。  相似文献   
46.
热处理对食荚豌豆贮藏品质的影响   总被引:8,自引:1,他引:8  
为探索热处理对食荚豌豆保鲜的效果,实验研究了40℃ 20 min、40℃ 40 min和50℃ 20 min热水处理对食荚豌豆在1℃贮藏期间主要生理和品质变化的影响。结果表明,采用40℃ 20 min和40 min热水处理不仅可有效降低食荚豌豆腐烂的发生,同时还可显著抑制豆荚的呼吸强度和多酚氧化酶(PPO)、过氧化物酶(POD)及苯丙氨酸解氨酶(PAL)活性,抑制豆荚丙二醛(MDA)和木质素含量的上升及叶绿素和维生素C含量的下降,从而起到延缓豆荚衰老和品质下降的作用,因而在食荚豌豆保鲜中具较好应用前景。50℃ 20 min热水处理对延缓食荚豌豆衰老和保持品质无明显作用。  相似文献   
47.
多年生香豌豆是1998年初从美国引进的豆科牧草之一,经过在黄土高原地区 3年的引种试验研究表明,其具有适应性强、生长迅速、耐旱、耐瘠薄、耐盐碱、产草量高 、适口性强、覆盖度强、种植技术简单等特点,是优良的水土保持和饲料植物.  相似文献   
48.
The objective of this study was to determine the chemical composition and in vitro dry matter (IVDMD) and neutral detergent fibre (IVNDFD) digestibilities of silages made from whole‐crop pea [Pisum sativum L. (PS)], pea–wheat [Triticum aestivum L. (PW)], pea–barley [Hordeum vulgare L. (PB)] and pea–oat [Avena sativa L. (PO)] mixtures harvested 8 weeks (H8) and 10 weeks (H10) after seeding. Forty‐five days after ensiling, all forages were well ensiled as indicated by low pH and low water‐soluble carbohydrate content and high lactic acid concentration. Regardless of forage type, crude protein (CP) and IVNDFD were higher while starch and acid detergent lignin were lower in H8 than H10. However, harvest date had no effect on neutral (NDF) and acid (ADF) detergent fibre of the silages. Within each harvest date, CP was higher while NDF was lower for PS than pea–cereal silages. Differences in CP and fibre fractions between the pea–cereal mixture silages were not consistent for the two harvest dates. The IVDMD of PS was higher than that of the three pea–cereal mixture silages in H8 but was only higher than that of PB in H10. For the pea–cereal mixtures, IVDMD was higher for PO than PB and PW in H8 and was higher for PB than PW in H10. It was concluded that silage from pea monoculture had similar forage yields and a generally higher nutritive value than silages from pea–cereal mixtures.  相似文献   
49.
在旱农区农田生态条件下,采用常规与二次回归正交结合的设计方法,多点同步研究定豌2号高产与密度、氮磷施用量及配比间的关系和相关效应,钼肥、保水剂高效施用技术,并在试验基础上同时进行生产示范验证。根据试验示范结果,选用相应分析程序进行计算机模拟寻优,得到定豌2号产量1 950~2 653 kg/hm2的技术方案65套。该方案95%置信域:播种量109.5~148.5万株/hm2,施N 45~64.5 kg/hm2,P2O5112.5~147kg/hm2,N∶P2O5约为1∶2.37,沟施植物保水剂7.5 kg,每1 000 g种子用钼酸铵4 g拌种。  相似文献   
50.
A total of 242 Pisum accessions were screened for resistance to Pseudomonas syringae pv. pisi under controlled conditions. Resistance was found to all races, including race 6 and the recently described race 8. Fifty‐eight accessions were further tested for resistance to P. syringae pv. syringae under controlled conditions, with some highly resistant accessions identified. Finally, a set of 41 accessions were evaluated for resistance to P. syringae pv. pisi and pv. syringae under spring‐ and winter‐sowing field conditions. R2, R3 and R4 race‐specific resistance genes to P. syringae pv. pisi protected pea plants in the field. Resistance sources to race 6 identified under controlled conditions were ineffective in the field. Frost effects were also evaluated in relation to disease response. Results strongly suggest that frost tolerance is effective in lowering the disease effects caused by P. syringae pv. pisi and pv. syringae under frost‐stress conditions, even in the absence of disease resistance genes, although the highest degree of this protection is reached when frost tolerance and disease‐resistance genes are combined in the same genetic background.  相似文献   
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