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1.
In order to increase the yield of short rotation willow coppice cultivated on agricultural land and to improve the biomass quality as an industrial and energy feedstock, particular consideration should be devoted to proper location and to the cultivation of woody plants. This paper presents the yield of five new cultivars of willow coppice and the relationship between the chemical composition of biomass and the plant harvest cycle. The Tur cultivar has been shown to have the highest mean productivity of 21.5 t of d.m. ha−1 year−1. In a three-year harvest cycle, the cultivar also gave biomass with the highest cellulose:lignin ratio (2.14). The significantly highest yield of dry biomass from the cultivars under study (20.5 t of d.m. ha−1 year−1) was achieved in a three-year harvest cycle. It was lower by 3.4% on average in a two-year harvest cycle and lower by 17.2% in a one-year harvest cycle as compared to a three-year cycle. As the harvest cycle was extended, the biomass quality in terms of its chemical composition improved. The biomass obtained in a three-year cycle contained the highest amount of cellulose (44.6% of d.m.) and the lowest amount of lignin (21.8% of d.m.). The results indicate that the agrotechnical factors, including the cultivar and the harvest cycle, affect not only the yield, but also the qualitative features of short rotation coppice willow biomass.  相似文献   
2.
Chickpea is an indeterminate species, which continues to flower and set new pods over a long period under wet and cool growing conditions, resulting in excessive canopy development and delayed maturity. We hypothesized that the chickpea's long season requirement could be reduced through introgression of short internode, double podding and early flowering. Four populations E100Ym/CDC Anna, 272-2/CDC Anna, 298T-9/CDC Anna, and 298T-9/CDC Frontier were developed to test this hypothesis with the first parents of each cross being the donor of the short internode, double podding and early flowering traits, respectively. Also, the donor parents E100Ym, 272-2 and 298T-9 were intercrossed. Segregating populations of F2 to F3:6 generations were then evaluated under greenhouse and field conditions. When expressed well, double podding significantly reduced time to maturity as compared to the single podding counterparts. The best double podding lines were about 1 week earlier maturing than the early parent and standard checks. Days to flowering (DF) was positively associated with days to maturity (DM) (r = 0.44, P < 0.001), and partial path analysis revealed that DF contributed to DM mainly via days to first pod maturity (DFPM). In the two early flowering populations 298T-9/CDC Anna and 298T-9/CDC Frontier, DF determined about 32% of the variation in DFPM. Conversely, the short internode trait had an undesirable effect, in that all the short internode segregants were too late to mature. In conclusion, the alleles for double podding and early flowering may be used to improve early maturity in chickpea and subsequently minimize the risks associated with the production of this crop in environments where the growing conditions allow excessive crop canopy development, as in the Canadian prairies.  相似文献   
3.
抗虫短季棉品种主要性状分析   总被引:1,自引:0,他引:1  
[目的]在短季棉育种实践中达到性状选择的统一和平衡。[方法]为提高抗虫短季棉育种成效,以1998~2009年国审及省审的11个品种为材料,对其主要性状及性状之间的相互关系进行了分析。[结果]短季棉品种将早熟、高产、优质集于一身是可能的,是其多个性状协调配合的结果;形态性状选择可作为短季棉选育的一个重要手段;短季棉的抗病性还有待提高。[结论]该研究可为减少今后短季棉育种的盲目性提供参考依据。  相似文献   
4.
选用辽宁省育成大豆品种铁丰27号和沈农6号与美国俄亥俄州育成大豆品种OhioFG1和HS97—4534作亲本,配成正反交4个杂交组合,探讨了短果枝性状的遗传情况。结果表明:不同组合正反交F3、F4代中短果枝上的每荚粒数有所不同,以高值亲本作母本高于用低值亲本作母本的,这说明短果枝上每荚粒数的遗传是细胞质遗传,且F4代结果大于F3代。以短果枝荚数和粒数多的材料做母本,其F3和F4代的短果枝荚数和粒数也较高。说明,在利用短果枝性状时,配置杂交组合应以短果枝荚数和粒数较多的试材做母本。亲本沈农6号是多短果枝品种,其短果枝粒重率高达22.87%,以它为母本与美国的OhioFG1杂交,其F4代中短果枝的粒重率也高达到7.21%。  相似文献   
5.
Short rotation woody biofuel plantations on reclaimed surface mines in Appalachia can diversify domestic energy supplies and facilitate the reforestation of these disturbed lands. This study examined growth, survival, biomass accumulation and allocation, and nitrogen concentrations following two growing seasons in American sycamore (Platanus occidentalis L.) and black locust (Robinia pseudoacacia L.) seedlings receiving irrigation, granular fertilization, and irrigation + fertilization compared with untreated controls. Fertilization increased basal diameter, height, and stem mass of American sycamore following two growing seasons. Increased stem production was attributed to accelerated development and not shifts in biomass allocation due to treatment. Irrigation and irrigation + fertilization treatments did not enhance growth or biomass accumulation of American sycamore. Similarly, black locust basal diameter, height, and stem mass did not differ among the treatments. Browse surveys showed that more than 76% of black locust seedlings experienced arrested or retrogressed growth due to browse; less than 3% of American sycamores were browsed. This intensive browse by ungulates, likely including reintroduced elk, may have affected growth differences among species and confounded the effects of treatments on black locust. Survival was unaffected by treatment in both species, but mean survival was greatest in American sycamore (80%) compared to black locust (58%). Per tree total nitrogen uptake was highest in fertilized American sycamore (7.9 g) and lowest in irrigated American sycamore (0.9 g). The results of our study suggest that granular fertilizer applications can accelerate seedling growth on reclaimed surface mines in the Appalachian region.  相似文献   
6.
短光低温不育水稻新种质的花药培养研究   总被引:4,自引:0,他引:4  
陆燕鹏  万邦惠  陈雄辉 《种子》2001,(1):15-16,19
对短光低温不育水稻进行花药培养的结果表明:不同基因型材料的花培力差异较大;同一材料在不同的基本培养基和激素配比中进行培养的效果不同,对宜DIS,以M8附加2,4-D(2mg/L) NAA(2mg/L) Kt(1.5mg/L)的花培力最高;不同时间段所取的材料花培力差异较大,可能与材料生长所处的最适环境不同有关;适当的通气状况有利于绿苗分化率的提高。  相似文献   
7.
王鹏  王英  闫鹏 《种子世界》2007,(3):33-34
当前小麦高产品种的育种目标定为9000~12000kg/hm^2,以光合生产潜力分析能够成功,采用扬守仁先生育种实践推出的5分制打分法,对小麦品种产量结构分析得出:加强株型选择,提高单株生产力是小麦高产育种的主要途径。  相似文献   
8.
马铃薯川芋6号鲜薯产量高,较脱毒川芋56[1]及脱毒米拉增产显著;具有株矮,生育期适中;抗病毒PVX、PVY,抗晚疫病;大中薯率高,休眠期较长,耐贮;鲜薯块茎干物质含量较高,维生素C含量高,还原糖含量低,食味优等优良特性。并适应性广,是鲜薯加工和食用兼用型品种,2004年通过四川省品种审定,并被列为四川省主要推广品种。  相似文献   
9.
伴随国家乡村振兴战略的不断推进,越来越多的农产品企业和农村群众借助“直播+短视频”的电商新模式形式进行自我表达和营销,去增加农产品销量。农产品“短视频+直播”的营销模式中存在创作者营销素养不够,缺乏专业性人才、内容同质化严重,出现信息茧房效应、产品品控难把握,售后服务不完善、监管体系尚不完善,存在漏洞和空白等问题。可以通过多措并举提升人才专业性、深挖产品内涵,创新内容、加强农产品品控管理,完善售后服务和建立完善的监管机制,明确各项制度规约等措施去更好地发挥三农“短视频+直播”的益处,为实现乡村振兴添砖加瓦。  相似文献   
10.
矮生香石竹的组织培养和快速繁殖   总被引:3,自引:0,他引:3  
矮生香石竹(代号为SJ-3)是本所采用切花香石竹和日本石竹杂交而成的优良新品种,该品种矮生、重瓣,没有种子,不能进行有性繁殖,因此利用组织培养技术、以矮生香石竹茎尖段为外植体,进行了组织培养快速繁殖研究。试验结果表明:(1)矮生香石竹增殖分化阶段的合适培养基为MS 6-BA0.2mg/L KT0.1mg/L NAA 0.05mg/L CCC 5ml/L;(2)合适的生根培养基为1/2MS NAA 0.5mg/L IBA0.5mg/L,生根率在86.6%;(3)在同等条件下采用透气的封口膜对克服矮生香石竹试管苗玻璃化有明显的效果;(4)生根试管苗移入珍珠岩∶河沙∶泥炭=1∶1∶1的基质中,成活率达93%,同时采用瓶外生根技术移栽成活率高,并缩短了试管苗的繁殖周期。  相似文献   
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