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61.
高粱品种资源光周期敏感性研究   总被引:1,自引:0,他引:1  
对996份中国高粱品种资源的光周期敏感性鉴定表明,中国高粱在每日10h短日照处理上,所有鉴定材料都比在自然光照下提前抽穗开花,而且品种间差异很大。按照分级标准,光反应迟钝的材料有35份,占3.5%;中间型的材料有736.份,占73.97%;敏感型的材料有225份,占22.6%。统计分析表明,光敏感的程度与鉴定材料的生育期及原产地的地理纬度有一定的相关性。同时,受日照的影响,鉴定材料的株高、叶片数变  相似文献   
62.
Sorghum [(Sorghum bicolor L.) Moench] is a highly productive crop plant, which can be used for alternative energy resource, human food, livestock feed or industrial purposes. The biomass of sorghum can be utilized as solid fuel via thermochemical routes or as a carbohydrate substrate via fermentation processes. The plant has a great adaptation potential to drought, high salinity and high temperature, which are important characteristics of genotypes growing in extreme environments. However, the climate change in the 21st century may bring about new challenges in the cultivated areas. In this review, we summarize the most recent literature about the responses of sorghum to the most important abiotic stresses: nutrient deficiency, aluminium stress, drought, high salinity, waterlogging or temperature stress the plants have to cope with during cultivation. The advanced molecular and system biological tools provide new opportunities for breeders to select stress‐tolerant and high‐yielding cultivars.  相似文献   
63.
The chemical, sensory and rheological properties of porridges made from blends of sprouted sorghum, bambara groundnuts and fermented sweet potatoes were examined. Sorghum and bambara groundnuts were sprouted for 48 h while sweet potatoes were fermented for the same period. Blends were formulated from the processed ingredients in the ratio of 60:40:0, 57:42:1, 55:44:1 and 52:46:2 (protein basis) of sorghum, bambara groundnuts and sweet potatoes. Porridges were prepared from the composite flours and the traditional sorghum complementary food. Standard assay methods were used to evaluate the flours for nutrient composition. The porridges were also tested for sensory properties and viscosity. Processing increased the levels of most of the nutrients evaluated. Relative to the sorghum traditional complementary food, thecomposite flours had higher levels of lipids, protein, ash, crude fiber and minerals (p<0.05). The porridges from the composite flours were generally liked slightly by the panelists and were about seven times less viscous than the porridge from the traditional sorghum complementary food. Use of the composite flours, particularly the 52:46:2 blend, as a traditional complementary food should be encouraged in Nigeria especially with the increasing cost of commercial complementary foods.  相似文献   
64.
Little information exists concerning how crops will respond to the predicted increased night temperatures. The objective of this work was to determine if respiration and growth of sorghum [Sorghum bicolor (L.) Moench], a C, plant, and sunflower (Helianthus annuus L.), a C3 plant, are affected when the night temperature is increased by 5°C compared to the long-term (19 year) average night temperature in June in Kansas. Sorghum and sunflower were grown in two walk-in growth chambers with either the ambient night temperature (21C) or a high night temperature (26C). Day temperature was the same for all plants (27C). Both sunflower and sorghum had higher respiration rates under the elevated night temperature than under the ambient temperature. The average respiration rate of sunflower grown under elevated night temperature increased by 19% (0.89 vs. 0.75 μmol m?2 s?1) and that of sorghum by 44 % (0.52 vs. 0.36μmol m?2s?1). After 74 days, sunflower plants grown under the ambient night temperature were 30.2 cm taller than sunflower plants grown under the elevated night temperature; sorghum plants under the ambient temperature were 24.8 cm taller. Sunflower plants grown under the elevated night temperature formed flowers one week earlier than those grown under the ambient temperature. Sorghum formed no flowers by 74 days. Results suggest that, if climate change does increase night temperature, respiration will be increased more in C4, than C3 plants.  相似文献   
65.
甜高粱与粒用高粱干物质积累分配与产量形成的比较研究   总被引:7,自引:1,他引:7  
1978—1988年,我们对甜高粱与粒用高粱的干物质积累、分配与产量形成进行了比较研究,结果表明:(1)两者干物质积累过程都可用 Logistic 模型描述,但甜高粱较粒用高粱干物质积累峰值高,后期积累速度快,单株生物量高。(2)甜高粱是具有穗和茎两个库的双库型作物,其营养生长与生殖生长并进时间长,几乎从拔节延续到成熟。甜高粱茎的  相似文献   
66.
高粱同源四倍体及其杂交种的细胞遗传学研究   总被引:10,自引:0,他引:10  
对同源四倍体高粱品系和杂交种的细胞学观察发现,其减数分裂的各个时期均有特异性。具体表现在,前期Ⅰ有3.94%的PMC中存在多个核仁,其中以双核仁形式出现的频率最高;终变期—中期Ⅰ具有不同的染色体构型,可观察到同源染色体的四种组成形式;后期Ⅰ出现大量落后染色体,其中以单价体提前分离造成的染色单体落后较为常见,单价染色体落后较少;前期Ⅱ和四分体时期可观察到核外染色体;中期Ⅱ发现有部分染色体不排列于赤道板上;后期Ⅱ仍有新的落后染色体产生。对四价体频率和后期Ⅰ带有落后染色体细胞出现频率进行的统计分析发现,品系间和不同的杂交种间存在显著的差异,说明染色体的配对能力和正常分配能力均受基因型影响。研究还发现,这两个重要的细胞学现象具有明显的负向超亲优势,杂交种的四价体频率明显降低,落后染色体明显减少。  相似文献   
67.
高粱区域试验新杂交种的综合评价   总被引:5,自引:0,他引:5  
采用模糊数学综合评判方法,综合评价了1989年山西省高粱新杂交种区域试验材料.结果表明,6个高粱新杂交种,其中晋杂871、21A×晋粱五号、FA×8643变3个组合以亩产量、丰产素质为主,包括抗病性、抗倒性、株高在内的综合性状明显优于对照晋杂四号,达到优良或较好的评价标准,其综合指标值分别比对照增加18.29%、11.28%和7.00%.晋杂871对不同环境的适应能力强,综合性状稳定性好;旱抗六、V_4A×87382-3两个杂交种综合特性与对照相当;旱抗五劣于对照,综合指标值比对照减少5.06%.模糊综合评判方法,客观地反映了品种的综合特性,克服了仅用产量指标评价品种优劣的不足,对新品种的审定、推广利用都具有实际意义.  相似文献   
68.
Summary Apomixis has been reported in a few lines of sorghum, among them R473 which was originally reported to be an obligate apomict. Although this line has multiple embryo sacs, the frequency of apomictic seed formation has not been determined because a progeny test has not been possible. R473 does not cross as a female with other lines except when its own pollen is present. In the present study mutations were induced in R473 by hydrazine and irradiation. Crosses were made between male-sterile mutants as females and normal R473 as males. Plants of R473 produced F1 hybrids sexually, thus indicating that they were not obligate apomicts. These F1's also reproduced sexually, as indicated by segregation for male sterility and male fertility in F2 progenies.  相似文献   
69.
Summary The polypeptide composition of Fraction-1-Protein (F1P) from rice × sorghum, rice × wheat hybrids and their respective parents have been analyzed by a microelectrofocusing method. The large sub-unit (LSU) is composed of three polypeptides and the small sub-unit (SSU) of two polypeptides in rice and sorghum parents and rice × sorghum hybrids. Similarly, LSU is composed of three polypeptides in the rice and wheat parents and rice × wheat hybrids. Two polypeptides occur in the SSU of rice parent and rice × wheat hybrids where as only one polypeptide in the wheat parent. These polypeptides also differ in their isoelectric points. Based on the previous reports of F1P inheritance in hybrids in other crops, F1P analysis of rice × sorghum and rice × wheat hybrids does not seem to be an important marker to identify such intergeneric hybrids. Since this is first such report of F1P inheritance in hybrids between distantly related plants, its implication in different modes of inheritance are discussed.Abbreviations F1P Fraction-1-Protein - IEF Isoelectric focusing - pI Isoelectric points - LSU Large sub-unit - RuBPCase Ribulose 1,5-Bisphosphate Carboxylase-oxygenase - SSU Small sub-unit  相似文献   
70.
Summary Two crosses of sorghum, Sorghum bicolor (L.) Moench (IS 1054 × ICSV-1, and IS 5604 × IS 1054) were evaluated in parental, F1, F2, and backcross generations for the variation in their popping quality as measured by pop volume (ml). Dominance was in the direction of low pop volume. Dominance and additive gene effects, in that order, governed most of the variation, while significant dominance x dominance type of interaction effects could also be detected. There was no evidence for higher order gene interactions.Approved as Journal Article 630 by the International Crops Research Institute for the Semi-Arid Tropics (ICRISAT), Patancheru, P.O. 502 324, Andhra Pradesh, India.  相似文献   
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