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1.
小麦雄性不育研究进展   总被引:1,自引:0,他引:1  
雄性不育是植物中的一种普遍现象,而雄性不育是利用杂种优势提高作物产量和品质的基础,因此小麦雄性不育的理论机制研究对农业生产具有重要的指导意义.对小麦雄性不育类型及遗传、生理生化不育机制、定位及分子生物学研究进行了综述,并探讨了今后该领域的研究前景.  相似文献   

2.
气候变化对黄淮海地区弱冬性小麦的影响评价   总被引:2,自引:0,他引:2  
气候变暖正在影响我国的农业生产.研究某一区域一定历史时期气候变化对农业的影响,可以使人们科学认识当地气候资源,更好地利用气候资源为农业生产服务.本文以黄淮海地区弱冬性小麦为例,利用DSSAT中的CERES-Wheat作物生长模型研究上世纪后40年气候变化对冬小麦生长发育及产量的影响,得出几点主要结论:气候变化对弱冬性小麦发育期影响不大,而对产量影响较大;灌溉能极大地提高冬小麦的产量.  相似文献   

3.
作物适宜度模型及其应用   总被引:2,自引:0,他引:2  
本文提出的适宜度理论和方法是一种描述作物与环境关系的定量方法,文中提出了两个新的概念;适宜度过程、环境因子变化过程适宜度。以此为基础,建立了一系列的适宜度模型及产量模型,将该理论及方法应用于分析定西春小麦生产,初步摸清了当地小麦产量长期低而不稳的规律。本文提出的春小麦产量模型具有明显的生物学含义并可用它在不同生物阶段对产量进行预测。经用1984、1986年的数据验证,模拟值与实值分别相差8%、7.  相似文献   

4.
以山西农业大学培育的冬小麦031165为供试材料,对水、旱地小麦采用浓度均为1 000 mg/kg的稀土溶液[La(NO3)3,Ce(NO3)3]进行浸种,研究其对小麦根苗生长、抗氧化酶系活性及产量的影响。结果表明:干旱胁迫抑制了小麦根苗生长,降低了小麦的实际产量。无论干旱胁迫与否,稀土浸种均能显著提高不同生育期小麦株高、地上干重、叶面积及根系生物量;稀土浸种可提高部分生育期旗叶中SOD、POD活性,降低胞内MDA含量,显著提高小麦产量和经济系数,且在干旱胁迫下作用较明显。从整体上看,Ce浸种对小麦生长的促进作用比La浸种明显。  相似文献   

5.
APSIM模型在黄土丘陵沟壑区不同耕作措施中的适用性   总被引:11,自引:0,他引:11  
为了揭示黄土丘陵区不同耕作措施对作物生长发育和土壤水分的影响及相互作用规律,根据2002~2005年两个轮作序列(小麦→豌豆(W→P)和豌豆→小麦(P→W))的3种耕作措施(传统耕作(T)、免耕(NT)和免耕覆盖(NTS))的定位试验,对APSIM模型的适用性进行了研究.通过定位试验得到了一套APSIM模型的参数值,并对其进行了率定.运用均方根误差法对APSIM模型进行检验,结果表明:小麦和豌豆产量与生物量的模拟值与实测值具有显著的正相关(R>0.9),误差范围在±15%之内;土壤贮水量的模拟值与实测值也具有显著的正相关(R>0.7),误差范围在±20%以内.表明APSIM模型可以用来模拟不同耕作方式和不同轮作序列的小麦和豌豆产量、生物量及土壤水分的动态变化,模型可以用于指导作物生产及耕作措施的优化管理.  相似文献   

6.
小麦种植在我省占有这样的地位,本文对黑龙江省小麦种植现状进行了分析,提出了适合我省小麦种植的几种创新技术及模式。  相似文献   

7.
APSIM模型在西南地区的适应性评价——以重庆冬小麦为例   总被引:6,自引:0,他引:6  
利用重庆市4个代表性站点的小麦田间观测数据和同期逐日气象数据对APSIM模型在重庆小麦产区的适应性进行研究,确定了12个小麦品种的作物参数.结果表明:模拟小麦的播种至出苗、开花和成熟各阶段天数与实测值具有较好的一致性,其均方根误差值分别为0~3、1~8和0~8 d;模拟的12个小麦品种中,模拟与实测地上部分生物量的归一化均方根误差(NRMSE)均低于30%,10个品种模拟与实测产量的NRMSE均低于30%,作物生育期、地上部分生物量和产量的模拟结果均在可接受范围内波动.说明APSIM模型对不同品种冬小麦的生育期、地上部分生物量和产量模拟效果较好,该模型在重庆地区具有较好的适应性,为后续基于模型评估该地区小麦生产提供了基础支撑.  相似文献   

8.
诱发突变育种技术是利用射线、离子、中子等物理辐射因素及空间环境诱变种子或植物离体组织,获得有益突变体,缩短育种周期的育种技术。据国际诱变育成品种数据库的不完全统计,截至2016年5月,世界上60多个国家在214种植物上诱变了超过3 200个正式发布的突变品种,21个国家诱变了254个小麦突变体,其中我国诱变小麦164个,占总量超过64%而位居世界第一。综述了诱变技术在小麦育种方面的成就,概述了获得的小麦农艺性状、产量、品质等性状突变,并对今后小麦诱变育种的目标及方法进行了展望。以期为小麦诱变育种的进一步发展提供借鉴,促进现代物理农业的应用及发展。  相似文献   

9.
农业是保障国民经济发展的基础,而提升粮食总产量就成为基础中的基础问题。小麦产量占有粮食总产量的重要比例,保证小麦产量,也就成为粮食问题中的一个关键问题,在小麦生长期中,病虫害往往是威胁小麦生长,影响产量的一个重要问题,所以,如何防治病虫害是保证粮食产量的一个关键问题,本文对此问题进行分析和创新研究。  相似文献   

10.
不同的气象条件下对大豆施肥水平的研究   总被引:1,自引:0,他引:1  
黑龙江省是我国大豆的主要产区,研究施肥对产量的影响可以加强对大豆生产的指导.本文运用所建立的大豆产量模型与降水型模型,采用频数分析法,求出在不同的气候类型下(丰年、平年、欠年),为了使大豆的单产达到某一水平,所需的各种肥料投入量的95%置信区间.这对于根据不同气候类型,在年初计划大豆的生产规模、各种肥料的投入量,安排农业生产都具有实用价值.  相似文献   

11.
Climate change threatens global wheat production and food security, including the wheat industry in Australia. Many studies have examined the impacts of changes in local climate on wheat yield per hectare, but there has been no assessment of changes in land area available for production due to changing climate. It is also unclear how total wheat production would change under future climate when autonomous adaptation options are adopted. We applied species distribution models to investigate future changes in areas climatically suitable for growing wheat in Australia. A crop model was used to assess wheat yield per hectare in these areas. Our results show that there is an overall tendency for a decrease in the areas suitable for growing wheat and a decline in the yield of the northeast Australian wheat belt. This results in reduced national wheat production although future climate change may benefit South Australia and Victoria. These projected outcomes infer that similar wheat‐growing regions of the globe might also experience decreases in wheat production. Some cropping adaptation measures increase wheat yield per hectare and provide significant mitigation of the negative effects of climate change on national wheat production by 2041–2060. However, any positive effects will be insufficient to prevent a likely decline in production under a high CO2 emission scenario by 2081–2100 due to increasing losses in suitable wheat‐growing areas. Therefore, additional adaptation strategies along with investment in wheat production are needed to maintain Australian agricultural production and enhance global food security. This scenario analysis provides a foundation towards understanding changes in Australia's wheat cropping systems, which will assist in developing adaptation strategies to mitigate climate change impacts on global wheat production.  相似文献   

12.
The direction of the time trend in wheat production efficiency from Soviet arid virgin lands is analyzed with the use of a developed agrohydrologic model. It is based on the concepts of water resource input (soil moisture) and corresponding agro output (spring wheat). The model evaluates each growing season and assigns a decimal value (from 0.0 to 1.0) which is then multiplied by maximum spring wheat yield. This derived product is that growing season's estimated yield. A nonparametric statistical method by Kendall is applied to examine the study period wheat production efficiency time trend. It is suggested that an increasing trend occurred over the study period.  相似文献   

13.
气候变化对我国华北地区冬小麦发育和产量的影响   总被引:34,自引:5,他引:29  
验证作物模型在我国华北冬小麦主产区是否适应的基础上,采用作物模型与气候模式相结合的研究方法,定量化地模拟预测了未来100年气候变化对华北冬小麦生产的影响.结果表明,从2000~2004年,华北地区冬小麦产量的模拟值与实测值的变化趋势基本一致,且生育期和产量变化不大.未来100年内华北地区冬小麦的生长期可能会有所缩短,平均缩短8.4 d;产量也会有不同程度的下降,平均减产10.1%.适当采取应对措施可以有效降低冬小麦的减产趋势.  相似文献   

14.
江苏省冬小麦湿渍害的风险区划   总被引:6,自引:0,他引:6  
吴洪颜  高苹  徐为根  包云轩 《生态学报》2012,32(6):1871-1879
选取能较好反映冬小麦春季湿渍害特征的3个气象因子:旬降雨量、旬日照时数和旬雨日,计算了江苏省1960—2008期间历年3—5月这3个因子的逐旬统计值,分析了这些因子与冬小麦气候产量的关系,研究结果表明:(1)春季旬降雨量、旬雨日和旬日照时数对江苏省冬小麦气候产量有显著影响;(2)通径分析显示,旬降雨量和旬日照对气候产量有直接影响,而旬雨日对气候产量有间接影响;(3)构建了一个湿渍害判别指数Q用来判别湿渍害发生年份,并结合江苏省各地湿渍害年发生频率和冬小麦气候减产率,建立了冬小麦湿渍害风险指数模型;(4)利用所建风险指数模型对江苏省冬小麦的湿渍害风险进行了区划和评估,并提出了各风险区的防御对策。  相似文献   

15.
Wheat is the main food for the majority of Iran’s population. Precise estimation of wheat yield change in future is essential for any possible revision of management strategies. The main objective of this study was to evaluate the effects of climate change, CO2 concentration, technology development and their integrated effects on wheat production under future climate change. This study was performed under two scenarios of the IPCC Special Report on Emission Scenarios (SRES): regional economic (A2) and global environmental (B1). Crop production was projected for three future time periods (2020, 2050 and 2080) in comparison with a baseline year (2005) for Khorasan province located in the northeast of Iran. Four study locations in the study area included Mashhad, Birjand, Bojnourd and Sabzevar. The effect of technology development was calculated by fitting a regression equation between the observed wheat yields against historical years considering yield potential increase and yield gap reduction as technology development. Yield relative increase per unit change of CO2 concentration (1 ppm?1) was considered 0.05 % and was used to implement the effect of elevated CO2. The HadCM3 general circulation model along with the CSM-CERES-Wheat crop model were used to project climate change effects on wheat crop yield. Our results illustrate that, among all the factors considered, technology development provided the highest impact on wheat yield change. Highest wheat yield increase across all locations and time periods was obtained under the A2 scenario. Among study locations, Mashhad showed the highest change in wheat yield. Yield change compared to baseline ranged from ?28 % to 56 % when the integration of all factors was considered across all locations. It seems that achieving higher yield of wheat in future may be expected in northeast Iran assuming stable improvements in production technology.  相似文献   

16.
Many of the irrigated spring wheat regions in the world are also regions with high poverty. The impacts of temperature increase on wheat yield in regions of high poverty are uncertain. A grain yield–temperature response function combined with a quantification of model uncertainty was constructed using a multimodel ensemble from two key irrigated spring wheat areas (India and Sudan) and applied to all irrigated spring wheat regions in the world. Southern Indian and southern Pakistani wheat‐growing regions with large yield reductions from increasing temperatures coincided with high poverty headcounts, indicating these areas as future food security ‘hot spots’. The multimodel simulations produced a linear absolute decline of yields with increasing temperature, with uncertainty varying with reference temperature at a location. As a consequence of the linear absolute yield decline, the relative yield reductions are larger in low‐yielding environments (e.g., high reference temperature areas in southern India, southern Pakistan and all Sudan wheat‐growing regions) and farmers in these regions will be hit hardest by increasing temperatures. However, as absolute yield declines are about the same in low‐ and high‐yielding regions, the contributed deficit to national production caused by increasing temperatures is higher in high‐yielding environments (e.g., northern India) because these environments contribute more to national wheat production. Although Sudan could potentially grow more wheat if irrigation is available, grain yields would be low due to high reference temperatures, with future increases in temperature further limiting production.  相似文献   

17.
臭氧胁迫下冬小麦物质生产与分配的数值模拟   总被引:2,自引:0,他引:2  
利用ML9810B型臭氧监测分析仪,测定了浙江嘉兴麦田空气O3浓度,并通过改进的开顶式气室实验确定O3浓度变化对冬小麦叶片光合速率的影响函数.在此基础上,加入O3对叶片生长和穗部光合影响的模拟函数,建立反映O3对冬小麦生长和产量形成影响的作物模型.模型的检验结果表明,该模型较好地反映了O3对冬小麦生长的影响,生物量平均相对误差为10.3%.对冬小麦春后生育期(3—5月)的研究表明,水肥适宜时,由O3影响造成的该地区冬小麦干物质累积总损失量为11.4%,产量损失为17.8%.  相似文献   

18.
黑龙江省玉米区域性农业生产数学模型的建立及应用   总被引:7,自引:0,他引:7  
  相似文献   

19.
以河南省30个站点1981—2014年冬小麦观测资料、历史气象资料和土壤资料为依据,将河南冬小麦主产区划分为5个区域,基于WOFOST作物生长模拟模型,分析了水分胁迫条件下河南省冬小麦减产风险值的变化规律.结果表明: 1981—2014年,各区域冬小麦减产率均呈上升趋势,平均每10 a增加2.8%~5.0%.冬小麦减产率由北向南呈降低趋势,减产率超过20%的事件在豫南地区约10年一遇,豫北的新乡、封丘和濮阳一带约2年一遇;减产率超过50%的事件,在新乡、郑州地区约3年一遇,豫南少遇.豫北及豫中偏北的大部分地区为冬小麦减产风险高值区,豫西卢氏、豫西南南阳、豫南信阳和驻马店南部地区为冬小麦减产风险低值区,其他地区为风险中值区.  相似文献   

20.
冬小麦单产的光谱数据估测模型研究   总被引:10,自引:0,他引:10       下载免费PDF全文
 本文在分析冬小麦群体经济产量与叶面积系数关系的基础上,以地面实测冬小麦反射光谱数据为依据,提出了一种新的动态VI-产量模型,即LAD-产量模型。该模型具有冬小麦生育后期(抽穗一灌浆末期)光合面积和光合时间等信息,其冬小麦单位面积产量(简称单产)估测精度为98%。另外,本文根据常用的某一特定生育期VI-产量模型,用冬小麦各生育期的VI值分别估测小麦单产,确定山东省禹城市冬小麦的灌浆中期为最佳估产时间。此时期.小麦单产估测精度为96%。  相似文献   

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