Effect of root morphological traits on zinc efficiency in Iranian bread wheat genotypes

Zinc (Zn) has a vast number of functions in plant metabolism, the lack of which had dramatic effects on growth and yield of plants. Plants have morphological and biochemical responses to enhance mineral solubility in the soil and facilitate uptake, such as root plasticity, secretion processes and symbioses. Root architecture modification is an important plant response to nutrient availability. The aim of this study was to identify root morphological reactions to Zn efficiency in Iranian bread wheat genotypes. Soil and solution cultures were used to survey Zn efficiency. In soil culture, six and seven genotypes with high and low Zn contents were selected among 110 Iranian bread wheat genotypes, respectively. The solution culture experiments were set up in a completely randomized block design and plants fed with Johnson’s grass solution. All traits were assessed at 30 and 60 DAPs (days after planting). Our results showed a significant difference between two groups of efficient and inefficient genotypes only at 60 DAP, and Zn-efficient genotypes showed 1.63-, 1.50-, 1.69- and 1.92-fold increases in root diameter, surface area density, shoot and root dry weight, respectively, compared to inefficient genotypes. In contrast, Zn-inefficient genotypes had 1.20- and 2.62-fold more root length and fineness, respectively, than efficient genotypes. The positive significant correlations were observed between shoot and Zn uptake as well as root dry weight and Zn uptake at both stages. Furthermore, shoot and root dry weight showed a significant correlation with root fineness, diameter and surface area density at both stages. The path analysis showed indirect effects on Zn uptake through root traits. Our results showed that roots have a major role in Zn efficiency. Therefore, the better growth and greater Zn uptake in efficient genotypes, compared to inefficient ones, can be attributed to greater root diameter and surface area density, and lower root fineness in these genotypes.     

Partitioning of phosphorus in different height isolines of winter wheat

Wheat (Triticum aestivum L.) grain yields and composition are influenced greatly by P and its interactions with other nutrients. Because most P in grain, like N, is remobilized from vegetative parts, high harvest index of dwarf wheats may adversely influence partitioning of P to grain. Isogenic tall, single semidwarf, and double dwarf ‘Pawnee’ wheat lines were used to characterize P partitioning, P nutrition before and after anthesis, and relationship between P and N. Plants were grown in hydroponic cultures with three P levels; the first study determined P, N, and dry matter accumulation from anthesis to maturity, the second study determined the effect of withholding P after anthesis on P, N, and dry matter partitioning during grain development. Plants continued to absorb P when it was available after anthesis, but grain growth was influenced more by P nutrition before anthesis than after anthesis. Leaf blades, sheaths, and stems were major sources of P for grain growth when the nutrient was withheld and major sites of P accumulation when the nutrient was supplied after anthesis. Content of N in plants was favored by ample P levels. Dwarfing genes increased harvest index, but had little effect on P partitioning because of differences in dry matter accumulation.     

21000-2300nm波段的小麦冠层光谱特性与叶面积指数和叶片氮含量间的关系及其受叶片水分含量的影响

The effects of leaf water status in a wheat canopy on the accuracy of estimating leaf area index （LAI） and N were determined in this study using extracted spectral characteristics in the 2 000-2 300 nm region of the short wave infrared （SWI） band. A newly defined spectral index, relative adsorptive index in the 2 000-2 300 nm region （RAI2000-2300）, which can be calculated by RAI2000-2300 = （R2224 - R2054） （R2224 ＋ R2054）-1 with R being the reflectance at 2 224 or 2 054 nm, was utilized. This spectral index, RAI2000-2300, was significantly correlated （P 〈 0.01） with green LAI and leaf N concentration and proved to be potentially valuable for monitoring plant green LAI and leaf N at the field canopy scale. Moreover, plant LAI could be monitored more easily and more successfully than plant leaf N. The study also showed that leaf water had a strong masking effect on the 2 000-2 300 nm spectral characteristics and both the coefficient between RAI2000-2300 and green LAI and that between RAI2000-2300 and leaf N content decreased as leaf water content increased.     

Nitrogen rate applied affects dry matter translocation and performance attributes of wheat under deficit irrigation

Crop production in arid/semi-arid regions is restricted by soil moisture and nitrogen (N) deficiencies. Consequently, sufficient levels of N and irrigation are important in improving the crop's productivity. Therefore, a 2-year field experiment was conducted to understand influences of watering techniques namely 300, 500 and 700 mm with contrasting N supply (0, 60, 120 and 180 kg ha^?1) on wheat cv. “landrace” productivity, dry matter translocation (DMT) and contribution of pre-anthesis assimilates to the grain (CPAAG, %). Experiments were conducted each year using a split-plot design with three replications at a private farm, North Hamedan Province, Iran. Accordingly, when 500/700 mm water was applied, CPAAG values were higher than those obtained after applying 300 mm water, i.e. 49.99 and 45.45 vs. 40.13%. The highest productivity in terms of grain yield, grain N concentration, nitrogen harvest index, special products analysis division and protein content was achieved in normal deficiencies of irrigation and N. This was further supported by a higher leaf area index, crop growth rate and N uptake of such treatment. Meanwhile, co-application of 120 kg N and 500 mm water significantly improved DMT, water and N use efficiency, and it was the optimal scheme for wheat production.     

利用高光谱指数进行冬小麦条锈病严重度的反演研究

通过选取不同条锈病抗性品种(高抗、高感、中间)进行田间不同梯度(对照、轻度、中度、重度)的接种试验,在接种后每隔7 d左右,同步测定了不同品种、不同处理的冠层光谱、单叶光谱和对应目标的病情指数以及叶面积指数、叶倾角等生物物理参数和叶绿素、SPAD数值等生物化学参数。通过对获取的光谱数据和生物物理参数和生物化学参数进行统计分析。研究结果表明,小麦被条锈病感染以后,叶片叶绿素含量急剧下降,通过研究叶片绿度值(SPAFD)值与叶绿素含量之间的关系,建立了叶片叶绿素含量和叶片SPAD数值之间的线性关系方程。通过在借鉴前人研究结果的基础上,通过筛选光谱指数,在冠层水平上构建作物冠层结构不敏感色素反演指数(CCII=TCARI/OSAVI)来反演全生育期不同处理的SPAD数值,此反演结果受品种类型、冠层结构和土壤背景的影响较小,线性方程的决定系数达到极显著的水平。在单叶水平选取归一化的光化学指数(NPRI)来反演单叶的病情指数(DI),线性方程的决定系数达到极显著的水平。所以该文通过选取适当的高光谱指数进行冬小麦条锈病严重度的反演的理论和方法是可行的。且反演结果受不同品种、不同叶面积指数和土壤背景等的影响均较小。     

氮肥基追比例对测墒补灌小麦冠层不同层次光能利用及干物质转运的影响

【目的】研究测墒补灌节水栽培条件下,氮肥基追比例对小麦植株冠层不同层次光能利用和干物质积累转运及分配的影响,为确定合理的氮肥运筹模式提供依据。【方法】以‘济麦22’小麦为试验材料,在总施氮量为240 kg/hm^2条件下,设置5个氮肥基追比例,分别为N1 (0∶10)、N2 (3∶7)、N3 (5∶5)、N4 (7∶3)、N5(10∶0),在拔节期和开花期,土壤相对含水量均补灌至田间持水量的70%。【结果】氮肥基追比例为5∶5的N3处理开花后的叶面积指数、冠层上层和中层的光合有效辐射(PAR)截获率及截获量显著高于其它处理,中层和下层的透射率显著低于其它处理,PAR转化率和利用率较N1、N2、N4和N5分别提高13.64%、8.02%、8.70%、14.38%和21.17%、8.50%、10.67%、23.88%。N3处理开花后干物质同化量、成熟期干物质积累量及中层营养器官开花前贮藏干物质向籽粒的转运量、转运率显著高于其它处理,籽粒干物质分配量较N1、N2、N4和N5分别提高11.37%、5.68%、6.03%和16.25%。相关分析表明,中层营养器官开花前贮藏干物质向籽粒的转运量与中层PAR截获率呈显著正相关;籽粒干物质分配量与上层、中层及总PAR截获率呈显著正相关,与下层PAR截获率呈显著负相关。【结论】氮肥基追比例为5∶5的处理显著提高了小麦冠层的光能利用,促进了中层营养器官开花前贮藏干物质向籽粒的转运,获得了最高的籽粒产量,为本试验条件下的最优处理。     

Effect of sulfur additions on soil and the nutrition of wheat

Abstract

A field experiment was conducted for two years to determine the effects of four sulfur (S) sources applied at various rates on the elemental composition of Coker 747³ wheat and on the soil S concentration. The concentration of S in plants increased by all sources of applied S. Increased S in the soil from S application decreased P concentrations in plants regardless of the S source used. Sulfur additions did not significantly affect the concentrations of Cu, Ca, Mg, or N in plants. The concentrations of Mn, Zn, and Fe in plants either increased or decreased depending on S source used. Analysis of the silt loam soil to a depth of 90 cm revealed that applied S moved readily from the surface to the lower depths and that the elemental form of S moved less rapidly than the more soluble forms of applied S.     

合理密植对不同株型烤烟冠层结构及光合生产特性的影响

【目的】研究不同耐密性烤烟对密植的综合响应,为鉴选耐密品种及烤烟合理密植提供理论参考。【方法】采用两因素裂区试验设计,以云烟97 (塔形,低耐密)、NC71 (腰鼓形,中等耐密)、K326 (筒形,高耐密) 3类株型烤烟为主区,4个种植密度(13890、15150、16660、18510株/hm^2)为裂区,阐明不同株型烤烟农艺性状、冠层结构、物质积累、产量及构成对密植的响应规律。【结果】密植条件下(15150、16660、18510株/hm^2),烤烟株高显著增加,最大叶叶位明显下降,并逐渐表现为"高瘦"形态。品种因素对株高和最大叶叶位影响显著,不同品种间茎围无显著差异。随种植密度的增加,烤烟群体叶面积系数(LAI)呈增加趋势,尤其是耐密品种NC71和K326的LAI显著增加,不同密度间K326品种LAI空间分布变异最低。密植主要通过提高群体干物质生产力(单位面积有效叶片数)弥补单株生产力(上中等烟率、单叶重)的不足,从而获得结构性增产。云烟97品种群体产量以16660株/hm^2时最高,平均较对照(13890株/hm^2)显著增加15.51%;NC71品种群体产量以16660株/hm^2和18510株/hm^2间无明显差异,较对照分别显著增加17.61%和19.37%;K326密植效应最大,以18510株/hm^2群体产量最高,比对照提高24.51%。成熟期云烟97单株干物质在15150株/hm^2后持续下降,降幅范围为8.41%～21.08%,NC71和K326品种则在密度为16660株/hm^2时有显著降低。合理密植可发挥烤烟群体结构性增产潜力,紧凑品种(NC71、K326)的高耐密性表现为个体生理对密植响应迟钝,从而获得功能性增产。【结论】合理密植可充分发挥烤烟群体结构性增产潜力,不同品种耐密性差异主要表现为个体功能对密植响应的迟钝性强弱,本试验条件下,K326、NC71、云烟97品种密植分别为18510株/hm^2、16660株/hm^2、15150～16660株/hm^2时,可实现烤烟群体结构和个体功能平衡。     

海河流域合理生态用水比例的确定

Winter wheat-maize rotations are dominant cropping systems on the North China Plain, where recently the use of organic manure with grain crops has almost disappeared. This could reduce soil fertility and crop productivity in the long run. A 20-year field experiment was conducted to 1） assess the effect of inorganic and organic nutrient sources on yield and yield trends of both winter wheat and maize, 2） monitor the changes in soil organic matter content under continuous wheat-maize cropping with different soil fertility management schemes, and 3） identify reasons for yield trends observed in Xuzhou City, Jiangsu Province, over a 20-year period. There were eight treatments applied to both wheat and maize seasons： a control treatment （C）; three inorganic fertilizers, that is, nitrogen （N）, nitrogen and phosphorus （NP）, and nitrogen, phosphorus and potassium （NPK）; and addition of farmyard manure （FYM） to these four treatments, that is, M, MN, MNP, and MNPK. At the end of the experiment the MN, MNP, and MNPK treatments had the highest yields, about 7 t wheat ha^-1 and 7.5 t maize ha^-1, with each about 1 t ha^-1 more than the NPK treatments. Over 20 years with FYM soil organic matter increased by 80% compared to only 10% with NPK, which explained yield increases. However, from an environmental and agronomic perspective, manure application was not a superior strategy to NPK fertilizers. If manure was to be applied, though, it would be best applied to the wheat crop, which showed a better response than maize.     

Adjustment of radiation use efficiency of winter wheat by air temperature at different irrigation regimes and nitrogen rates

In this research, radiation use efficiency (RUE) of winter wheat was determined under different irrigation regimes and nitrogen application rates in experimental field at southwest Iran (semi-arid region) in 2009–2010 and 2010–2011. The experiment was laid out as a split plot design, with irrigation treatments as main plots and N fertilization as sub-plots with three replications. Irrigation treatments were 1.2 (I4), 1.0 (I3), 0.8 (I2), and 0.5 (I1) times of the full irrigation requirements and N treatments were 0 (N1), 46 (N2), 92 (N3), and 136 (N4) kg ha^?1. Air temperature had significant effects on RUE that was adjusted by multiplication of hourly temperature factor to the hourly values of solar radiation (RUE _a ). The values of RUE _a were significantly different from the values of RUE in both growing seasons. The values of RUE _a ranged from 1.44 to 1.83 g MJ^?1 and 1.45 to 1.81 g MJ^?1 in 2009–2010 and 2010–2011, respectively. In both growing seasons, minimum and maximum values of RUE were at I1N1 and I4N4 treatments, respectively. The methods of daily maximum and minimum air temperature were modified for considering the effects of air temperature on RUE at locations where hourly air temperature and radiation were not available.     

不同灌溉条件下不同类型冬小麦产量水分利用效率差异原因分析

以旱地品种"西峰20"和"晋麦47"、水旱兼用型品种"石家庄8 号"、高水肥地品种"石4185"和"科农9204"5 个冬小麦品种为材料, 通过田间不同灌溉处理试验研究了不同抗旱类型冬小麦品种收获指数和群体水分利用效率对产量水分利用效率的影响差异。结果表明: 不同抗旱类型的小麦在不同灌溉处理下, 产量水分利用效率(WUE_y)以及变化趋势存在显著差异。旱地冬小麦品种WUE_y 和收获指数(HI)显著低于水地品种和水旱兼用型品种。不同品种间WUE_y 最大相差42.01%, HI 相差25.91%。HI 和群体水分利用效率(WUE_bm)与WUE_y 呈显著正相关关系。株高与HI 呈显著负相关关系(R²=0.574)。在不灌溉条件下, 品种间WUE_y 差异源自HI 的差异; 而在补充灌溉条件下, 品种间WUE_y 的差异源自WUE_bm 和HI 的共同作用。说明不同抗旱类型的小麦对不同灌溉处理的响应方式和适应策略不同。旱地品种在干旱胁迫条件下, 主要靠增加WUE_bm 来提高WUE_y; 而水地品种和水旱兼用型品种在补充灌溉中凭借较高的WUE_bm 和HI 共同作用提高WUE_y。     

Improving the performance of bread wheat genotypes by managing irrigation and nitrogen under semi-arid conditions

Wheat (Triticum aestivum L.) productivity is generally affected by water limitation and inadequate nitrogen supply especially under semi-arid environment. The current study was conducted to determine whether the crop yield and irrigation water use efficiency (IWUE) could be manipulated through alteration of nitrogen and irrigation application. To meet the desired objectives, a two-year field study was carried out in 2013–2014 and 2014–2015, in a split-split plot arrangement with three factors i) irrigation in main plots, ii) nitrogen in sub-plots, and iii) twenty genotypes in sub-sub plots on a sandy loam soil. The analysis of variance revealed that the wheat performance was affected by genotypes and alteration of irrigation and nitrogen application with respect to IWUE and final grain yield. IWUE under water stress conditions was observed 56% higher than normal irrigated. Much higher values of IWUE under water stress indicated that the existing optimum water requirements of the crop needs to be revaluated. The regression model indicated that addition of nitrogen and irrigation patterns along with morphological traits cannot explain variation in yield related traits more than 65% under semi-arid conditions. Therefore, for better crop yields in semi-arid environment, more physiological parameters should be considered in evaluation of yield.     

灌溉频率对冬小麦产量及叶片水分利用效率的影响

为了探讨中国北方冬小麦高效节水灌溉模式,采用了3种灌溉处理:在拔节期一次灌溉120mm,在拔节期和抽穗期各灌溉60mm及在拔节期、抽穗期和灌浆期各灌溉40mm,研究了在总灌溉量为120mm的情况下,灌溉频率对冬小麦产量及叶片水分利用效率的影响.结果表明,在冬小麦的拔节期和抽穗期各灌溉60mm,显著提高乳熟期和蜡熟期旗叶...     

华北平原冬小麦面积遥感提取及时空变化研究

多年作物种植面积的时空变化可以反映种植结构的调整结果,并可用于进行驱动力分析。为解决连续遥感监测作物种植面积变化过程中,不同的训练样本或分类规则不能较好地反映作物种植面积时空格局变化的问题,本文首先根据研究区(华北平原)农业气象观测站提供的主要农作物物候观测资料获得主要农作物典型物候期特征,结合HANTS滤波后的NDVI时间序列数据提取不同地物类型的NDVI时序曲线,引入复种指数,探讨了CART算法在提取华北平原冬小麦种植面积的可行性,最后提取了2000—2013年华北平原冬小麦种植面积,并参考市级的农业统计数据进行精度评价。经检验,近13年的遥感监测种植面积与农业统计面积相关系数达到0.94(置信水平为95%),且各市13年面积一致性小于40%的概率仅为15%。利用遥感监测多年冬小麦空间分布信息获得其空间种植概率,能较好地反映研究区冬小麦的主要种植区,该方法可为大范围、连续年份冬小麦种植面积时空格局的遥感监测提供参考。     

Mathematical model for the analysis of irrigation water and fertilizer management for spring wheat in the semiarid area of West Liaoning,China

Soybean plants (Glycine max L. cv. Akisengoku) were grown in water culture in a greenhouse. At the pod-setting and pod-filling stages, plants were subjected to stem-ringing or treated with high concentration of nitrate. Respiration and N₂ fixation (acetylene reducing activity) were studied in individual nodules along with the concentrations of ATP and magnesium.

There was a high positive correlation between respiration activity and acetylene reduction in soybean nodules. The maintenance respiration in mature nodules corresponded to a CO₂ evolution of 5.5 µmol/g F.W., and the respiratory cost for nitrogen fixation was estimated at 2 mg C liberated/mg N fixed, though this value was probably underestimated due to CO₂ fixation by the nodules. For the nitrogenase activity there was a threshold value of ATP concentration at around 0.15 µmol/g F.W., and the activity increased up to around 0.35 µmol/g F.W., beyond which the ATP concentration did not increase unlike the nitrogenase activity. The values for the magnesium concentration in the nodules detected in the present experiments were above the optimum level.     

Response of photosynthetic active radiation interception,dry matter accumulation,and grain yield to tillage in two winter wheat genotypes

ABSTRACT

To examine the effects of winter wheat genotypes on dry matter (DM) accumulation and grain yield (GY) under no-tillage conditions in North China Plain (NCP), a field experiment was conducted using the genotypes Tainong 18 (F) and Jimai 22 (J). Two tillage systems were tested, conventional tillage (CT) and no-tillage (NT) during the 2015/2016 and 2016/2017 winter wheat growing seasons. Genotypes and tillage systems were compared regarding DM accumulation, GY, leaf area index (LAI), photosynthetic active radiation (PAR) interception, and flag leaf fluorescence parameters. LAI, PAR interceptions, and flag leaf fluorescence parameters were significantly higher under CT than under NT conditions. This suggests that the efficiency of light harvesting by the PSII reaction center of leaves can increase due to CT. DM accumulation was significantly higher under CT than under NT. Spike DM accumulation was higher in F than in J in the heading and the filling stages. In both growing seasons, GY was significantly higher under CT than under NT, GY of NTF was significantly higher than that of NTJ, which was due to a significantly higher number of kernels per spike. This indicates that genotype F can compensate for a low GY due to NT.     

微咸水灌溉对华北平原冬小麦根际微生物的影响

针对我国华北平原淡水资源短缺这一现状,合理利用其地下微咸水进行农业灌溉是缓解水资源供需矛盾的有效途径。持续5年的田间定位试验,开展微咸水灌溉对冬小麦根际微生物影响的研究,试验共设置5个试验处理:雨养(NI)、淡水和微咸水交替灌溉(FS)、淡水灌溉(FF)、微咸水灌溉(SS)、微咸水和淡水交替灌溉(SF)。研究结果表明:FS和SS处理导致土壤表层(0～10 cm)EC值显著增加29.9%～52.4%,并且SS处理对冬小麦造成了盐胁迫。但微咸水灌溉(FS、SS、SF)较FF处理未对根际微生物Alpha多样性和群落结构造成显著影响,仅SS处理显著增加了部分属生物标记物如噬冷菌属(Algoriphagus)和有害菌壳球孢属(Macrophomina)等的相对丰度。较雨养而言,灌溉处理(FS、SS、FF、SF)导致表层土壤含水量(SWC)和pH分别增加42.4%～56.2%和3%～5.2%;硝态氮(NO^3--N)和铵态氮(NH4+-N)含量分别减少52.7%～65.2%和27.5%～43.2%。SWC值是影响根际细菌多样性的主要因子,因此,灌溉处理显著增加了根际细菌Alpha多样性;但未对真菌多样性造成显著影响。同时,根际微生物群落结构均受土壤pH值和NO^3--N含量影响,因此灌溉处理和NI处理群落结构存在差异,显著增加了纤维弧菌属(Cellvibrio)和有益菌角菌根菌属(Ceratobasidium)等属生物标记物的相对丰度。以上研究表明,长期使用3 g·L-1微咸水灌溉未对根际微生物多样性及群落结构造成显著影响,但是会改变部分属生物标记物相对丰度。这些研究结果为华北平原冬小麦微咸水灌溉的推广应用提供科学依据和理论基础。     

黑龙港低平原高产田小麦追肥研究

在严重干旱的 1999～ 2 0 0 0年 ,采用 3个品种 ,3个追肥量 ,3个追肥时期和 3次重复的完全组合设计 ,对大运河以东黑龙港低平原区高产田小麦春季追氮时期和追氮量进行了系统研究。结果表明 :春季追肥时期宜晚 ,第一次肥水在 4叶 1心到 5叶 1心期为好 ,追肥量以尿素 75kg/hm2 为高限 ,甚至可以考虑不追肥。     

Response of sunflower hybrids to nitrogen application grown under different agro-environments

A wide gap exists between production and consumption of vegetable oils in Pakistan. Thereby, a significant proportion (2.28 million tons) of vegetable oils is being imported at the cost of 2257 million US$. Therefore, the present study was conducted to quantify the comparative performance of various sunflower hybrids as influenced by various levels of nitrogen (N) fertilizer under different agro-environments. The experimental treatments consisted of three sunflower hybrids (Hysun33, Hysun38, and Pioneer-64A93) and five levels of N fertilizer (0, 60, 120, 180, 240 kg N ha^?1), arranged in a randomized complete block design in a split plot with four replications. The field trials were conducted for two consecutive crop seasons under three different agro-ecologies (arid, semi-arid, and sub-humid) in the province of Punjab, Pakistan. The results of the study demonstrated that the productivity of sunflower hybrids varied greatly in response to N fertilization and different ecologies. Maximum achene yield of 3177 kg ha^?1 was harvested under sub-humid environment, followed by the semi-arid one. Among the hybrids, Hysun38 excelled the other two hybrids with a production of 3083 kg ha^?1 and 41% oil contents. Generally, the productivity of hybrids increased with the increasing doses of N fertilizer. Maximum achene yield was obtained by addition of 180 kg N ha^?1. The findings of the study revealed that yield potential of Hysun-38 could be exploited by addition of N fertilizer at the rate of 180 kg N ha^?1 under sub-humid environment.     

华北平原地下水压采区冬小麦种植综合效应探讨

华北平原冬小麦-夏玉米一年两熟种植模式为维护国家粮食安全发挥了重要作用。但冬小麦生长期正处于华北平原降水较少的干旱季节,实现高产依赖于灌溉,是华北平原地下水超采的主导因素之一。随着国家地下水限采政策的实施,在地下水超采区如何稳定冬小麦的种植面积和产量是面临的一个重要问题。本文通过综述以往研究并结合典型地点田间试验结果,从冬小麦种植可减少休闲期土壤蒸发损失、具有的深根系系统可充分利用土壤储水、可利用微咸水替代淡水灌溉、通过限水灌溉发展优质麦生产、冬春形成覆盖层美化和防沙尘效应等方面论述了华北平原种植冬小麦的优势,提出华北平原冬小麦生产需要转变传统高耗水高产量理念,充分发挥冬小麦抗旱、耐盐能力强的特点,在不实施大规模压缩冬小麦种植面积条件下,通过冬小麦限水灌溉和微咸水利用满足对地下水压采需求,充分发挥华北平原冬小麦种植冬春防风沙、美化环境的生态功能,同时满足区域口粮安全的保障功能。