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1.
作物水分利用率的影响因素及其提高途径探讨   总被引:7,自引:0,他引:7  
综述了作物水分利用率的研究进展。在探讨水分利用率内涵的基础上,阐述了作物水分利用率的影响因素如作物,环境因素,化学制剂,栽培措施和耕作制度等人类活动等影响因素,重点分析了土壤因素和化学制剂对作物水分利用率的影响,探讨了作物水分利用率的提高途径,包括优化种植结构;选用节水高产型品种;农田覆盖保水技术;水肥耦合技术;化学调控节水技术和节水灌溉技术等  相似文献   

2.
is a model that has been developed at INRA (France) since 1996. It simulates crop growth as well as soil water and nitrogen balances driven by daily climatic data. It calculates both agricultural variables (yield, input consumption) and environmental variables (water and nitrogen losses). From a conceptual point of view, relies essentially on well-known relationships or on simplifications of existing models. One of the key elements of is its adaptability to various crops. This is achieved by the use of generic parameters relevant for most crops and on options in the model formalisations concerning both physiology and management, that have to be chosen for each crop. All the users of the model form a group that participates in making the model and the software evolve, because is not a fixed model but rather an interactive modelling platform. This article presents version 5.0 by giving details on the model formalisations concerning shoot ecophysiology, soil functioning in interaction with roots, and relationships between crop management and the soil–crop system. The data required to run the model relate to climate, soil (water and nitrogen initial profiles and permanent soil features) and crop management. The species and varietal parameters are provided by the specialists of each species. The data required to validate the model relate to the agronomic or environmental outputs at the end of the cropping season. Some examples of validation and application are given, demonstrating the generality of the model and its ability to adapt to a wide range of agro-environmental issues. Finally, the conceptual limits of the model are discussed.  相似文献   

3.
小麦叶片水分利用效率及相关生理性状的关系研究   总被引:39,自引:4,他引:35  
张娟  张正斌  谢惠民  董宝娣  胡梦芸  徐萍 《作物学报》2005,31(12):1593-1599
利用19个抗旱性不同的小麦品种,对干旱状态下叶片水分利用效率和光合速率、蒸腾速率等12个指标之间的关系进行了研究。结果表明,叶片水分利用效率与叶片光合速率、蒸腾速率、气孔导度、胞间二氧化碳浓度、水势和叶片离体失水速率之间的关系密切,说明这些生理性状是瞬间和短时期叶片水分利用效率的直接影响因素;而与叶片抗氧化酶活性、蜡质含量、叶片湿度和相对含水量相关性不大。因此认为,应该有针对性地研究与水分利用效率关系密切的生理性状,为小麦抗旱节水遗传育种研究提供理论依据。  相似文献   

4.
This paper reviews the knowledge on effects of climate change on agricultural productivity in Europe and the consequences for policy and research. Warming is expected to lead to a northward expansion of suitable cropping areas and a reduction of the growing period of determinate crops (e.g. cereals), but an increase for indeterminate crops (e.g. root crops). Increasing atmospheric CO2 concentrations will directly enhance plant productivity and also increase resource use efficiencies.

In northern areas climate change may produce positive effects on agriculture through introduction of new crop species and varieties, higher crop production and expansion of suitable areas for crop cultivation. Disadvantages may be an increase in the need for plant protection, the risk of nutrient leaching and the turnover of soil organic matter. In southern areas the disadvantages will predominate. The possible increase in water shortage and extreme weather events may cause lower harvestable yields, higher yield variability and a reduction in suitable areas for traditional crops. These effects may reinforce the current trends of intensification of agriculture in northern and western Europe and extensification in the Mediterranean and southeastern parts of Europe.

Policy will have to support the adaptation of European agriculture to climate change by encouraging the flexibility of land use, crop production, farming systems etc. In doing so, it is necessary to consider the multifunctional role of agriculture, and to strike a variable balance between economic, environmental and social functions in different European regions. Policy will also need to be concerned with agricultural strategies to mitigate climate change through a reduction in emissions of methane and nitrous oxide, an increase in carbon sequestration in agricultural soils and the growing of energy crops to substitute fossil energy use. The policies to support adaptation and mitigation to climate change will need to be linked closely to the development of agri-environmental schemes in the European Union Common Agricultural Policy.

Research will have further to deal with the effect on secondary factors of agricultural production, on the quality of crop and animal production, of changes in frequency of isolated and extreme weather events on agricultural production, and the interaction with the surrounding natural ecosystems. There is also a need to study combined effects of adaptation and mitigation strategies, and include assessments of the consequences on current efforts in agricultural policy to develop a sustainable agriculture that also preserves environmental and social values in the rural society.  相似文献   


5.
陇中半干旱区马铃薯集雨限灌效应研究   总被引:6,自引:1,他引:5  
采用大田试验与实验室分析相结合的方法,研究了集雨限灌对旱作马铃薯田蒸散量、灌水利用率、产量、产量性状及薯块品质的影响。结果表明,集雨限灌45 mm条件下马铃薯水分利用效率(WUE)显著提高,在此基础上增加灌水量,WUE降低;苗期限灌处理的WUE和灌水利用效率(IWUE)均高于薯块膨大期;苗期限灌45 mm处理综合用水效率较高。限灌可提高旱作马铃薯产量、大薯率与中薯率,降低小薯率,苗期限灌有利于大薯率的提高,薯块膨大期限灌有利于中薯率的提高;限灌降低马铃薯单株结薯数,可提高单株薯产量;超过45 mm随限灌量的增加,产量增加不显著,绿薯率和烂熟率显著增加。限灌能降低马铃薯薯块淀粉含量,提高薯块蛋白质含量。苗期限灌45 mm为半干旱区马铃薯最佳集雨限灌模式。  相似文献   

6.
This study reports the adaptation of a simple and mechanistic crop growth model for faba bean (FAGS) to growing conditions in the Mediterranean region. The FAGS model was originally developed for small-seeded cultivars grown in the temperate zone under non-limiting water and nutrient conditions. In order to account for the effect of drought stress on faba bean growth, a submodel for the simulation of soil water balance has been included in the FAGS model. The enhanced FAGS model was calibrated using data from field experiments with a large-seeded faba bean genotype (ILB 1814) conducted in 1993–1994 and 1994–1995 at ICARDA's Tel Hadya research station in northern Syria. In both seasons, crops were sown on two dates under different water supply levels. The model was capable of predicting the faba bean phenology, leaf area development, biomass production, and grain yield as well as the soil water extraction using daily climatic data, genotype-specific parameters, and soil physical properties. The calibrated faba bean model was tested against independent experimental data from the 1991–1992 and 1992–1993 growing seasons at Tel Hadya and was able to satisfactorily predict grain yield of crops grown under different drought intensities. Limitations of the model and aspects requiring better understanding to improve model predictions are discussed.  相似文献   

7.
二倍体小麦种间水分利用效率的差异及与根系生长的关系   总被引:16,自引:0,他引:16  
张岁岐  山仑 《作物学报》2003,29(4):569-573
提高作物水分利用效率(WUE)是当前半干旱地区农业研究的热点问题.利用管栽和田间干旱棚试验在两种土壤水分条件下,研究了5个不同二倍体小麦种WUE的差异及其与根系生长之间的关系.结果发现:两种水分条件下,不同二倍体小麦种间WUE存在显著差异,其从大到小的排列顺序为RR>DD>AA>BB,说明R染色体组上可能存在控制高水分利用效率  相似文献   

8.
The studies on anthropogenic climate change performed in the last decade over Europe show consistent projections of increases in temperature and different patterns of precipitation with widespread increases in northern Europe and decreases over parts of southern and eastern Europe. In many countries and in recent years there is a tendency towards cereal grain yield stagnation and increased yield variability. Some of these trends may have been influenced by the recent climatic changes over Europe.A set of qualitative and quantitative questionnaires on perceived risks and foreseen impacts of climate and climate change on agriculture in Europe was distributed to agro-climatic and agronomy experts in 26 countries. Europe was divided into 13 Environmental Zones (EZ). In total, we had 50 individual responses for specific EZ. The questionnaires provided both country and EZ specific information on the: (1) main vulnerabilities of crops and cropping systems under present climate; (2) estimates of climate change impacts on the production of nine selected crops; (3) possible adaptation options as well as (4) adaptation observed so far. In addition we focused on the overall awareness and presence of warning and decision support systems with relevance for adaptation to climate change.The results show that farmers across Europe are currently adapting to climate change, in particular in terms of changing timing of cultivation and selecting other crop species and cultivars. The responses in the questionnaires show a surprisingly high proportion of negative expectations concerning the impacts of climate change on crops and crop production throughout Europe, even in the cool temperate northern European countries.The expected impacts, both positive and negative, are just as large in northern Europe as in the Mediterranean countries, and this is largely linked with the possibilities for effective adaptation to maintain current yields. The most negative effects were found for the continental climate in the Pannonian zone, which includes Hungary, Serbia, Bulgaria and Romania. This region will suffer from increased incidents of heat waves and droughts without possibilities for effectively shifting crop cultivation to other parts of the years. A wide range of adaptation options exists in most European regions to mitigate many of the negative impacts of climate change on crop production in Europe. However, considering all effects of climate change and possibilties for adaptation, impacts are still mostly negative in wide regions across Europe.  相似文献   

9.
探讨品种间差异改良作物水分利用效率   总被引:2,自引:0,他引:2  
提高水分利用效率是缓解水资源危机实现作物可持续生产的重要策略。本文对叶片尺度的瞬时WUE和单株尺度WUE的品种间差异,瞬时WUE到田间尺度WUE的尺度转换,以及瞬时WUE与产量之间的关系进行了讨论。瞬时WUE具有较大的遗传变异性,在亏水条件下品种间差异更显著。在禾谷类作物上,气孔导度与瞬时WUE密切相关。单株尺度WUE在亏水条件下品种间差异显著,足水条件下差异相对较小。气孔导度是影响单株尺度WUE的重要性状,品种之间气孔对水分亏缺的敏感性差异较大。瞬时WUE向田间尺度WUE的尺度转换不仅受到冠层阻力和边界层阻力的制约,还受土壤蒸发与作物蒸腾比率以及同化物分配模式的影响。瞬时WUE与产量的关系决定于环境的水分条件,在作物生长发育主要依靠土壤中储存水分的干旱条件下,瞬时WUE高对获得高产有利。相反,在水分条件较适宜的地区,高瞬时WUE性状不利于高产。  相似文献   

10.
The sustainability of biomass sorghum (Sorghum bicolor L. Moench) in the Mediterranean environments is linked to the potential to increasing the crop productivity using irrigation water of different qualities: fresh and wastewater. An experiment was conducted in Southern Italy during 2012 and 2013 growing seasons to determine the biomass production and to estimate the yielded energy from sorghum irrigated with fresh water and municipal wastewaters. Two stages of wastewater reclamation process were compared: tertiary and secondary treatments.During the growing seasons, the crop growth (biomass and LAI) was surveyed on sorghum crops irrigated with three water qualities. In order to determine the effects of the irrigation water qualities on the final energy yielded, on the harvested biomass, structural components (cellulose, hemicellulose and lignin contents for deriving the ethanol production) and high heating value were analyzed. The data obtained during two crop seasons showed that, sorghum irrigated with municipal wastewater plant produced more dry biomass (23.3 vs 20.3 t ha−1), energy yield (383 vs 335 GJ ha−1), and ethanol (6824 vs 6092 L ha−1) than sorghum biomass with fresh water. As a consequence, the water efficiency for producing bioenergy increased when the waste waters were supplied in substitution of fresh waters. Different indices were calculated for comparing the effect of the water quality on the water use efficiency (WUE) of biomass sorghum crops.  相似文献   

11.
This study analyses the role of variability induced by climate and soil properties (texture and total available soil water in the root zone, TAW) on the “corn deficit irrigation–water use efficiency” relation over a 25-year period, between 1981 and 2005, in three different sites located in the South of Italy. The analysis of water use efficiency was carried out by means of three indexes: crops water use efficiency (WUEET and WUET) and irrigation water use efficiency (IWUE). These indexes can be obtained by calculating the ratio between the yield and the seasonal values of evapotranspiration (ET), transpiration (T) and irrigation volume (I). After its validation, the STICS model was retained to simulate the variables required to determine these indexes.Climatic variability affected the three indexes in different ways during the 25-year period studied. The dispersion around the mean values of the water use efficiency is 17% on average for the WUE (ET or T) indexes, whereas it could reach 54% for the IWUE index. This last index is only poorly reliable due to the high variability of rainfall during the corn growing season in the Mediterranean region.For the same level of soil water deficit, TAW led to an improvement (the case of the site with a high TAW and loam–clay soil texture), a stabilisation (the case of the site with a high TAW and clay soil texture) or a decrease (the case of the site with a poor TAW and clay soil texture) in WUEET and WUET values. For the same conditions of soil water deficit and TAW, crops water use efficiency was higher in loam textured soil than in clay soil.The results derived by analyzing three indexes (WUEET, WUET and IWUE) converge to the same conclusions on the “corn deficit irrigation–water use efficiency” relation observed at the three different sites.The hypotheses which may explain the differences observed in the different sites studied in terms of water use efficiency are discussed, with the presentation of some suggestions devised for corn irrigation practices.  相似文献   

12.
黑龙港流域不同滴灌制度下的冬小麦产量和水分利用效率   总被引:3,自引:0,他引:3  
针对华北黑龙港流域冬小麦–夏玉米种植制度中冬小麦灌溉水用量过大的问题,以节水和稳产为目标设计了冬小麦滴灌制度定位试验,比较了滴灌与漫灌及不同滴灌模式下的小麦产量和水分利用效率。结果表明,在实验年份的降水条件下,传统灌溉定额和次数(总量225 mm,分1~3次灌溉)的滴灌与漫灌处理的小麦产量和水分利用效率差异均不显著;在两年降水特点不同的情况下,滴灌量比对照减少45~105 mm的处理产量下降不显著,水分利用效率显著提高。相关分析结果表明,对产量的贡献表现为穗粒数>千粒重>穗数。研究结果初步表明,冬小麦滴灌技术在黑龙港流域具有节水稳产的潜力。  相似文献   

13.
张耗  杨建昌 《作物杂志》2016,32(5):67-280
以三种主要粮食作物(水稻、小麦、玉米)为材料,设置常规灌溉(对照)和节水灌溉处理(水稻全生育期轻干湿交替灌溉技术、小麦控制土壤干旱灌溉技术、玉米控制低限土壤水分的分区交替灌溉技术),研究了节水灌溉技术对三种粮食作物产量和水分利用效率的影响。结果表明:与对照相比,节水灌溉技术的产量增加了8.56%~9.23%,水分利用效率提高了25.00%~31.43%。节水灌溉技术显著降低了三种粮食作物叶片的蒸腾速率和着生角度,显著增加了弱势粒中脱落酸(ABA)与赤霉素(GA3)的比值(ABA/GA3)、茎中蔗糖磷酸合成酶(SPS)和子粒中蔗糖合酶(SuS)活性、平均灌浆速率、茎鞘中非结构性碳水化合物(NSC)的运转率以及收获指数,显著提高了水稻和小麦的分蘖成穗率。表明减少奢侈的蒸腾和无效分蘖冗余生长、改善冠层结构、促进物质运转和子粒库活性、提高收获指数是节水灌溉技术协同提高产量和水分利用效率的重要原因。  相似文献   

14.
[目的]为了探明在高寒冷凉区芸豆生长的水肥耦合效应,[方法]采用田间试验法,研究了施肥和覆膜垄沟种植对旱地芸豆耗水特征、水分利用效率及产量的影响。[结果]结果表明,在底墒较好,降水丰富的年份,施肥和覆膜垄沟种植的产量与农户模式相比,均有显著提高,单株荚数是其产量提高的关键因素;高肥具有明显的增产和提高水分利用效率的作用,在此基础上的覆膜垄沟种植可有效的减少土壤水分损耗,而显著的提高水分利用效率。[结论]在高寒冷凉区,水分和养分都是作物生长的限制因子,在施肥和覆膜垄沟种植方式下,水肥互作效应显著,能够大大的提高产量和水分利用效率。  相似文献   

15.
The effect of soil texture on water use efficiency (WUE) was analyzed for six crops cultivated on loam and clay soils. Results were obtained after a long-term study, carried out in a lysimetric set-up, in conditions of experimental neutrality (climate, agro-techniques, and variety were the same for each crop) with the sole exception of the soil texture, which was the variable to be studied.In the case of potato, corn, sunflower, and sugar beet, WUE was reduced significantly when crops were grown in clay soil. The reductions ranged from 22% to 25%. The decrease of WUE in clay soil was coupled with significant reductions in yield and in ET, except in the case of the corn crop. The reduction in WUE in corn depended solely on the yield decrease.A 10% decrease in WUE values was also observed for the soy-bean and tomato grown in clay soil, but it was not statistically significant.Different causes which may reduce the WUE values observed in the clay soil are discussed. It seems coherent to hypothesize that, during the active growing phase, a deficit in water uptake occurs in the plants growing in the clay soil. This hypothesis is consistent with the observations of stomatal conductance, daily evapotranspiration, and leaf surface.In conclusion, the operative development of this study is outlined.  相似文献   

16.
冬小麦限水灌溉条件下磷肥补偿效应的研究   总被引:9,自引:1,他引:8  
为探索磷肥对土壤水分亏缺的补偿效应,研究了灌水和施磷对冬小麦耗水和产量等的影响。结果表明,冬小麦总耗水量与灌水量成正相关关系,而土壤贮水肖耗量与灌水量成负相关关系;施磷能提高作物耗水量,促进深层土壤水分的消耗。灌水和施磷均能显著提高冬小麦产量;两者相比,灌水增加了单位面积穗数和提高了千粒重,而施磷仅增加了穗数。灌水对经济系数无明显影响,但明显降低水分利用效率;施磷对经济系数和水分利用效率均无明显影  相似文献   

17.
Among the most important Mediterranean annual crops, durum wheat is widely grown in drought-prone areas. Therefore, improving water-use efficiency (WUE) of durum wheat represents a major breeding goal. IDu-WUE (Improving Durum wheat for Water Use Efficiency and yield stability through physiological and molecular approaches) is a collaborative project among public and private research centres in Italy, Spain and WANA (West Asia and North Africa) countries (Morocco, Tunisia, Syria and Lebanon) funded by the European Union aimed at investigating the genetic variation for WUE and yield stability in durum wheat grown in Mediterranean droughtprone areas. During the first year of the project, a number of morpho-physiological traits (e.g. early vigour, flowering time, leaf rolling, number of fertile tillers, etc.), WUE, WUE-related traits (e.g. carbon isotope discrimination, canopy temperature, chlorophyll fluorescence, etc.), yield and its components have been investigated in a RIL population (249 lines) and a collection of ca. 190 durum wheat accessions characterized by a high level of linkage disequilibrium (Maccaferri et al., 2005),  相似文献   

18.
为探索半湿润偏旱区沟垄集雨种植模式下冬小麦田土壤蓄水保墒和节水增产效果, 于2007-2010年连续3个小麦生长季在渭北旱塬旱农试验站, 研究了不同沟垄集雨种植模式对土壤水分、冬小麦产量和水分利用效率的影响。设置3个沟垄集雨处理, 分别是垄上覆盖地膜+沟内不覆盖(P1)、沟内覆盖小麦秸秆(P2)、沟内覆盖液体地膜(P3)处理, 以传统平作(CK)为对照。P1、P2和P3处理显著提高冬小麦生育前期0~20 cm和20~100 cm的土壤贮水量, 其中以P2处理蓄水保墒效果最显著, P3处理由于液态地膜的降解, 仅在小麦生长前期有一定的蓄水保墒作用, 在小麦的生长后期与P1处理无显著差异;各沟垄集雨处理100~200 cm土壤贮水量与CK无差异。P2处理对冬小麦平均株高和生物量影响最大, 3年平均株高和生物量分别较对照提高26.7%和60.3%。以P2处理增产效果最显著, 3年平均产量和水分利用效率分别较CK对照提高39.3%和35.6%;且P1和P3之间无显著差异。因此, 垄覆地膜、沟覆秸秆的二元沟垄集雨覆盖种植模式能显著提高冬小麦产量和水分利用效率, 适宜在半湿润偏旱区冬小麦生产中应用。  相似文献   

19.
高产冬小麦水分利用效率及其组分特征分析   总被引:17,自引:0,他引:17  
贾秀领  蹇家利 《作物学报》1999,25(3):309-314
依据8年田间和盆栽试验,分析了冬小麦基因型、密度和供水对水分利用效率(WUE)的影响。结果表明:当供水量变化范围较大时,总耗水(ET)和WUE呈显著线性负相关,ET对WUE的负效应明显大于产量(GY)对WUE的正效应。GY和ET有正相关趋势。当供水量变化范围较小时,GY和WUE呈显著线性正相关。蒸散效率(ETE)和收获指数(HI )都和WUE有正  相似文献   

20.
Improved water use efficiency (WUE, the ratio of dry matter produced to water used) can potentially result in yield improvement in water-limited environments. Genetic variation in WUE can be exploited by carbon isotope discrimination (Δ) in C3 species. In order to improve WUE and its associated traits, it is necessary to understand the genetic systems controlling the expression of these traits. A full diallel analysis carried out on five inbred lines selected from a previous field experiment revealed that Δ, WUE and specific leaf weight (SLW, the ratio of leaf dry weight to leaf area) had high narrow-sense heritability (Hn, the ratio of additive variance to phenotypic variance) and were controlled largely by additive gene effects indicating that these traits can be improved by selection in early generations. In contrast, maternal effects had a large influence on phenotypic expressions of total dry matter yield, total water use, chlorophyll content and leaf area suggesting the important role of selection of female parent for improvement of these traits. The parental line R49 was found to be the best general combiner for all of the traits. Genetic variation in SLW was strongly associated with Δ (R 2 =0.49, P < 0.01). This implies that SLW could be used as an inexpensive alternative measure for Δ to assess genotypes during the early phases of breeding programmes.  相似文献   

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