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基于AEZ模型的我国农区主要作物单产潜力分析 总被引：3，自引：0，他引：3
根据联合国粮农组织（FAO）和国际应用系统分析研究所（ⅡASA）基于中国1961年以来的统计资料共同开发的AEZ模型,运用GIS平台计算了中国41个农作制亚区6大主要作物（水稻、小麦、玉米、马铃薯、油菜、大豆）的单产潜力。指出以上作物单产最高潜力分布为：水稻在江淮江汉平原,小麦在秦巴山区,玉米在黄淮平原南阳盆地,马铃薯在秦巴山区,油菜在秦巴山区,大豆在鲁西平原鲁中丘陵。研究结果表明：我国以上主要作物的最高单产潜力是目前全国平均单产的1.2～2.9倍。这对指导我国农作物高产育种及栽培具有重要参考意义。 相似文献
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不同静电场处理种子对作物叶片几种生理指标的影响 总被引：1，自引：0，他引：1
摘 要: 分别用不同场强的静电场处理吸胀大豆、黄瓜和油青菜心种子,栽种20 d后测定作物叶片中可溶性蛋白含量、过氧化物酶（POD）活性、叶绿素含量和叶绿素a（Chla）荧光动力学参数的变化。结果表明,用相同强度的静电场处理不同的作物种子,作物叶片生理指标的反应不同;用不同强度的静电场处理同一作物种子,作物叶片的生理指标也有差异,显示出了静电场作用的“阈值效应”。用适宜剂量的静电场处理吸胀种子能有效地提高叶片中可溶性蛋白含量和过氧化物酶活性,增加叶片光合色素的合成,提高叶片光合细胞中光合反应中心Ⅱ（PSⅡ）的光合潜力和原初光能转换效率。 相似文献
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高海拔旱地油菜开花盛期光合生理特性研究 总被引：1，自引：1，他引：0
为了探索气候变化对作物光合生理特性的影响,在油菜开花盛期,采用LI-6400便携式光合仪测定祁连山高海拔旱地环境因子和油菜叶片光合生理指标,并分析油菜光合生理指标在不同年型、不同播期的差异。结果表明：油菜叶片净光合速率日变化呈双峰型曲线,存在“午休”现象,且上午的光合速率高于下午。油菜的蒸腾速率日变化呈双峰型曲线,气孔导度日变化大体呈“S”型曲线。而光合有效辐射和空气温度均呈单峰型日变化曲线,而空气湿度呈“S”型日变化曲线。通过显著性相关分析,油菜开花盛期光合有效辐射是影响叶片净光合速率的主导环境因子之一(R2=0.6916),光合有效辐射和空气温度是蒸腾速率的主导影响因子之一(RPAR2=0.7133,RT2=0.5611),空气湿度是气孔导度的主导影响因子之一(R2=0.5503)。湿润年油菜不论是外在环境还是植株体内在环境均处于适宜状态,作物各项光合参数均高于干旱年。分期播种的油菜叶片蒸腾速率表现出极显著性差异（P<0.001）,净光合速率、气孔导度差异显著（P<0.05）,细胞间隙CO2浓度差异不显著。 相似文献
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西南地区不同套种模式对土壤肥力及经济效益的影响 总被引：2，自引：0，他引：2
为探讨不同作物组合的种植模式对土壤肥力及经济效益的影响,寻找作物搭配合理、低投入高产出的套作模式。采用单因素随机区组试验,研究比较了4种套作模式(小麦/玉米/大豆、小麦/玉米/甘薯、小麦/高粱/大豆、马铃薯/玉米/大豆)的土壤肥力、产量及经济效益的差异。连续种植3年后,各种植模式的土壤养分含量基本维持或得到提升(速效钾除外)。甘薯茬口对全钾、速效钾消耗均较大,需适当提高钾肥用量。小麦/玉米/甘薯的总产量最高,小麦/玉米/大豆模式的大豆单产量最高,小麦的单产各模式无显著差异。不同模式收益表现为,小麦/玉米/大豆马铃薯/玉米/大豆小麦/玉米/甘薯小麦/高粱/大豆;产投比表现为,小麦/玉米/大豆马铃薯/玉米/大豆小麦/玉米/甘薯小麦/高粱/大豆。小麦/玉米/大豆收益为14196.41元/hm~2,产投比为3.69:1,均为所有模式中最高,加之大豆茬口可以活化土壤养分,是相对理想的套作模式。 相似文献
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本文根据联合国粮农组织(FAO)和国际应用系统分析研究所(IIASA)基于中国1961-1997的统计资料(经多方校正)共同开发的AEZ模型,运用GIS平台计算了中国41个农作制亚区的小麦生产潜力,并指出了单产最高潜力分布区域。研究结果表明:我国小麦的最高产量潜力大约将是目前产量的2-3倍。这对我国小麦高产育种及栽培具有重要参考意义。 相似文献
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近30年冀东地区气候变化对气候生产力的影响 总被引：2，自引：2，他引：0
【研究目的】为了摸清全球气候变化背景下冀东地区年平均气温及年降水量变化情况,以及由此对作物气候生产力产生的影响和未来气候变化情景下作物气候生产力水平。【方法】笔者利用冀东地区11个观测站1977-2006年气象资料与统计资料,在分析年均气温和降水量变化的基础上,应用Thornth waite Memorial模型,计算气候生产力对年均气温和降水量变化的响应情况。【结果】结果表明：（1）该区气温增速为（0.41~0.75）℃/10a,年降水量波动减少,但不显著;（2）过去30年间气候生产力总体呈减少趋势,但不明显,气候生产力利用率平均为43.3%,呈提高的趋势;（3）未来不同气候情景下,“暖湿型”气候将使气候生产力增加7%~20.8%,“冷干型”气候将使气候生产力降低7.1%~9.7%。【结论】（1）年平均气温变化在山区、平原和沿海地区表现出很好的一致性,年降水量表现出非一致性;（2）本地区作物气候生产力随年平均气温和年降水量的增加而增加,单一的气温升高和降水量增加均可使气候生产力增加,降水量不足构成作物气候生产力变化的主要限制因子之一;（3）本地区作物生产力还有很大的潜力,针对非作物本身因素提高单产还有可能;（4）未来气候变化情境下,“暖湿型”气候对本地区气候生产力增加最有利,“冷干型”气候对气候生产力增加最不利。 相似文献
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R. A. Illipronti Jr C. J. Langerak W. J. M. Lommen P. C. Struik 《Journal of Agronomy and Crop Science》2000,184(2):81-88
In a glasshouse experiment it was examined whether narrow grading and selection from a commercial soybean seed lot cultivar 'IAS-5', could improve the uniformity of the seed crop grown from it and thereby enhance yield, quality and uniformity of seeds produced. The classes created were: Control (original seed lot); Size-graded seeds (projected area measured by image analysis 37–46 mm2 ); Non-cracked seeds; Yellow seeds; Size-graded sound seeds (size-graded, non-cracked, yellow, non-wrinkled, non-etched). Compared to the control, percentage of emergence, survival and number of yielding plants were enhanced in crops from non-cracked, yellow or size-graded sound seeds. Differences in plant numbers did not result in differences in crop yield. The different seed lots also did not differ in crop uniformity: time interval between stages of plant development, plant height 20 days after sowing, yield components, physical or physiological quality attributes of seeds produced, and respective coefficients of variation were similar. Fewer plants survived in crops showing a larger variation in plant height 20 days after sowing, thus reducing differences in initial plant-to-plant variation. Creating more uniform crops by additional grading or selection of commercial seed lots may therefore not be promising. 相似文献
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不同氮素籽粒生产效率类型籼稻品种产量及其构成的基本特点 总被引：4，自引：0，他引：4
在群体水培条件下，以国内、外不同年代育成的常规籼稻代表品种（2001年为88个、2002年为122个）为材料，测定叶面积系数、干物重（包括根系）、氮素含量、产量及其构成因素等，采用组内最小平方和的动态聚类方法将供试品种按氮素籽粒生产效率(NUEg)从低到高依次分为A、B、C、D、E、F等6类，研究各类品种产量构成的基本特点。结果表明，（1）供试品种间NUEg的差异很大（344%、425%），A、B、C、D、E、F类品种的平均NUEg 2001年分别为20.51、31.04、35.64、39.46、43.55、50.92 g·g-1，2002年分别为24.33、31.61、35.83、39.06、43.51、50.00 g·g-1；（2）随着NUEg水平的提高，籼稻品种的产量水平显著提高，两年结果一致；多元回归分析表明，氮素总吸收量（包括根）和NUEg对产量均有显著影响，改良二者均可提高籼稻品种的产量水平；（3）高NUEg类品种的基本特点为单位面积穗数较多、库容量大、结实率高、抽穗期叶面积系数较小、抽穗期单位叶面积籽粒产量高、经济系数高，而每穗颖花数、千粒重以及生物产量等与籼稻品种的NUEg水平关系不密切。 相似文献
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在京郊不同土壤肥力条件下,进行小麦、玉米两茬间氮、磷、钾肥合理施用的研究.三年多点试验结果表明,全年氮素投入0.036～0.048kg/m~2,以小麦、玉米各半或玉米居多为宜.冬小麦施氮在下茬玉米上无明显后效.冬小麦适宜施氮量为0.024kg/m~2,夏玉米适宜施氮量0.030kg/m~2,冬小麦和夏玉米施磷肥不仅对当季有增产作用,而且对下茬作物也有明显的后效.冬小麦施P_2O_5 0.015kg/m~2、夏玉米0.007kg/m~2为宜.夏玉米比冬小麦对钾肥高度敏感,土壤速效钾含量在90×10~6以下,冬小麦施钾有一定增产效果,而夏玉米施钾肥显著增产. 相似文献
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Exogenous Glycinebetaine Enhances Grain Yield of Maize, Sorghum and Wheat Grown Under Two Supplementary Watering Regimes 总被引：1，自引：1，他引：1
P. C. Agboma M. G. K. Jones P. Peltonen-Sainio H. Rita E. Pehu 《Journal of Agronomy and Crop Science》1997,178(1):29-37
Drought occurring at critical growth and developmental stages in cereals affects productivity by reducing biomass accumulation, grain set, and grain yield and quality. Maize (cv. SR-73), sorghum (cv. Trump), and wheat (cv. Spear) were established in drought-prone field conditions in Perth, Western Australia, in l994. The plants were then subjected to optimal and suboptimal supplementary watering regimes at growth stages that were sensitive to water availability. Glycinebetaine in aqueous solution was applied to leaves at three rates (2, 4 and 6 kg ha?1 and a control) to establish whether its application could ameliorate the effects of drought on the yield of the crops. Above-ground biomass production was measured at the beginning and at termination of the watering regimes. Leaf tissue glycinebetaine concentrations were determined 1 and 3 weeks after application. At physiological maturity, grains from the crops were harvested and grain yield, number of grains m?2 and single grain weight were recorded. Drought significantly reduced above-ground biomass production in maize (P = 0.047), but not in sorghum and wheat. Grain yield of maize, number of grains m?2 of maize and sorghum, and single grain weight of sorghum were significantly depressed by drought. Foliar application of aqueous glycinebetaine marginally enhanced biomass production in the three crops and significantly increased grain yield of maize (P = 0.001) and sorghum (P = 0.003). It also resulted in more grains m?2 of maize, sorghum and wheat (P = 0.001, 0.001 and 0.003, respectively), with interactions between water and glycinebetaine treatments for sorghum and wheat (P = 0.001 and 0.001. respectively). Residual tissue glycinebetaine levels remained high 3 weeks after application to the crops. The positive effects of glycinebetaine treatment appear to be linked to its physiological role as a plant osmoticum that improves drought tolerance. The results of these studies suggest that foliar application of glycinebetaine may be used to improve drought tolerance and economic yield of maize and sorghum, but not of wheat. Increased grain yield was associated with more grains m?2 rather than greater single grain weight. 相似文献
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Ghazi N. Al-Karaki 《Journal of Agronomy and Crop Science》1998,181(4):229-235
Pre-sowing osmotic seed treatments were evaluated as a means of improving water uptake and germination performance of wheat ( Triticum durum L. cv. Hourani-27) and barley ( Hordeum vulgare L. cv. ACSAD 176) under four levels of water potential (0, –0.4, –0.8 and –1.2 MPa) created by using polyethylene glycol 8000. Seeds were osmoprimed in aerated solutions of 0.0, 0.2, 0.4 or 0.6 M KCl at 24 ± 2°C overnight and then rinsed and dried. Rate of water uptake by seeds was higher in osmoprimed than untreated seeds of both crops regardless of the water potential level. Decreasing water potential (more stress) adversely affected rate of water uptake in seeds of both crops. Seeds osmopriming increased germination percentage and decreased time to 50% germination at high water potentials (low stress), whereas the germination at low water potentials (more stress) was not affected by osmopriming treatments. The effect of osmopriming on rate of water uptake, germination percentage, and time to 50% germination was more pronounced in wheat than in barley. Reduction in the lag time of imbibition may be accounted for in part by some germination rate enhancement in the osmopriming treatments. Fresh weight and length of shoots (plumules) and roots (radicles) were enhanced in osmoprimed seeds in comparison to untreated seeds, in both crops at high water potentials (0 and – 0.4 MPa). As water potential in the medium decreased, these traits were inversely affected regardless of osmopriming treatment. Longer roots in wheat compared to barley were noted in the positive osmopriming treatments at high water potentials (0 and – 0.4). These results might indicate that wheat is more responsive than barley at relatively high water potentials to osmopriming through rapid penetrating root system. 相似文献
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Han-Yong Kim Jonghan Ko Seungtaek Jeong Jun-Hwan Kim Byunwoo Lee 《Journal of Crop Science and Biotechnology》2017,20(5):417-427
Determining effective measures to alleviate the impact of climate change on crops under various regional environments is one of the most urgent issues facing agriculture. In this study, geographic regions of South Korea for future-adjusted barley cultivation were outlined and the impact of climate change on barley production in the next 100 years was evaluated under two greenhouse gas concentration trajectory scenarios: the representative concentration pathway (RCP) 4.5 and RCP 8.5. To achieve our intended study goals, a geospatial crop simulation modeling (GCSM) scheme was formulated using CERES-barley model of Decision Support System for Agricultural Technology (DSSAT) crop model package version 4.6 to simulate grid-based geospatial crop yields. Two experiments were carried out at an open field to obtain model coefficients for the nation and at temperature gradient field chambers to evaluate the performance of the CERES-barley model under elevated temperature conditions. Suitable cultivation regions for three different types of barley (naked, hooded, and malting) under changing climate were projected to expand to the northern regions under both RCP 8.5 and RCP 4.5. However, they were projected to expand more rapidly under RCP 8.5 than those under RCP 4.5. Projected yields of four barley varieties were increased with a slow phase as year progressed under RCP 4.5 scenario. However, they were rapidly increased under RCP 8.5 scenario. It appears that geospatial variation in barley yield under changing climate can be effectively outlined. Therefore, GCSM system might be useful for determining impacts of climate change on geospatial variations of crops, potentially providing means to impede food insecurity. 相似文献
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为增强气象为农服务能力,保障粮食生产安全。以1981—2017年武威市各县（区）定点观测光热水资源和农作物生育及产量资料为基础,运用气候倾向率、相关系数法、SPSS13.0统计软件,分析了光热水资源变化及匹配特征和对农作物的影响。结果表明:（1）1981—2017年,武威市各县（区）≥10℃活动积温和日照时数呈极显著增大趋势,且增加幅度和稳定性从北向南逐渐减小,期间降水量呈略增加趋势,中北部光、热、水资源稳定增加,适宜作物生长的气候区域在扩大。（2）水热系数呈减小趋势,干燥度除民勤略减小外,其他县（区）呈略增大趋势;光温积呈极显著增大趋势,而光温比民勤和凉州呈极显著增加趋势,古浪和天祝呈极显著减小趋势;光温匹配在向利于农作物产量形成发展。（3）从相关系数看,光热资源增加促进喜凉作物生育和结实进程,光热匹配利于提高喜温作物子粒重和经济产量。从全市光、热、水资源匹配看,天祝和古浪浅山区适宜喜凉作物生长,有发展畜牧业和林业的气候条件。民勤、凉州和古浪川区适宜种植喜温作物,玉米、甜高粱、谷子、向日葵和瓜果,适宜发展特色农业。 相似文献
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The effect of agronomic practices and cultivars on grain yield, grain protein and small grain sievings was examined in field
experiments over four years in the winter rainfall wheatbelt of Western Australia. Rotation with legume crops and pastures
was the main factor responsible for increasing grain protein percent. Grain proteins were increased by 4-5% for crops grown
in good legume pasture rotations compared to continuous wheat rotations, but only by 1-2% by factors such as delayed sowing
time, applied nitrogen, cultivar or grass weed control. In legume based rotations, wheat crops sown at their highest yielding
times produced proteins in the appropriate ranges for premium paying grades. Applying N fertilisers up to the optimum rates
for yield did not result in proteins below the levels required for premium paying grades, except for hard wheats at >11.5%
grain protein. Legume rotations and appropriate soil types were required for hard wheats to exceed 11.5% at economic N rates.
The yield penalty often associated with high quality cultivars has been reduced or eliminated in the modern cultivars used
in the experiments. Some longer season cultivars only produced grain proteins >10% if sown after their optimum time for yield,
but sowing at optimum time reduced the probability of producing small grain sievings. Some cultivars were more susceptible
than others to producing excessive sievings, especially those with inherently smaller than average seed size. Seed rates up
to the optimum for grain yield did not result in excessive small grain sievings except where the site was highly fertile,
where the crop was sown too late for optimum yield or where too much N fertiliser was used.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
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The effect of salinity on seed germination, plant yield parameters, and plant Na, Cl and K concentrations of chickpea and lentil varieties was studied. Results showed that in both crops percentage emergence was significantly reduced by increasing NaCl levels (0–8dSm?1). From the plant growth studies it was found that differences existed among chickpea and lentil varieties in their response to NaCl application. In chickpea, the variety Mariye showed the comparatively lowest germination percentage and the lowest seedling shoot dry weight in response to salinity and was also among the two varieties which had the lowest relative plant height, shoot and root dry weight and grain yield at maturity. Similarly, variety DZ-10-16-2, which was the second best in germination percentage and the highest in terms of seedling shoot dry weight, also had the highest relative plant height, shoot and root dry weights, and grain yield at maturity. In lentil, however, such relationships were less pronounced. Chloride concentration (mg g?1) in the plant parts at salt levels other than the control was about 2–5 times that of Na. K concentration in the plants was significantly reduced by increasing NaCl levels. Chickpea was generally more sensitive to NaCl salinity than lentil. While no seeds were produced at salinity levels beyond 2dSm?1 in chickpea (no seeds were produced at this salt level in the most sensitive variety, Mariye), most lentil varieties could produce some seeds up to the highest level of NaCl application. Overall, varieties R-186 (lentil) and Mariye (chickpea) were the most sensitive of all varieties. On the other hand, lentil variety NEL-2704 and chickpea variety DZ-10-16-2 gave comparatively higher mean relative shoot and root dry weights, and grain yield, thus showing some degree of superiority over the others. The observed variations among the varieties may be useful indications for screening varieties of both crops for salt tolerance. 相似文献