土壤水分胁迫对冬小麦生长的后效影响

为揭示土壤水分胁迫对冬小麦生长的后效影响及其规律,利用盆栽试验对供试冬小麦设置13种供水处理,测定作物株高、叶面积、冠干重及产量,研究水分胁迫对上述生理指标的后效影响。结果表明,中度水分胁迫对株高的后效影响大于重度水分胁迫,在重度水分胁迫下,除C5-A外,当前影响均大于后效影响;前期中度水分胁迫对叶面积的后效影响大于当前影响,后期则相反,重度水分胁迫对叶面积的当前影响大于后效影响;水分胁迫对冠重的后效影响大于当前影响;水分胁迫对冬小麦穗数的后效影响基本上表现为正效应,而对每穗粒数、千粒重、产量及WUE的后效影响则全部为负效应,拔节至孕穗阶段中度水分胁迫抽穗期复水的处理产量最高,达到对照的62%。不同程度、不同历时、不同生育阶段的水分胁迫,对作物生长均有后效应,并导致小麦减产。     

Effect of Water Stress on Physiological Attributes and their Relationship with Growth and Yield of Wheat Cultivars at Different Stages

The effects of water stress on physiological attributes of drought‐sensitive (Kalyansona) and drought‐tolerant (C‐306) wheat cultivars were studied in a pot experiment. Water stress was imposed by withholding irrigation at boot and anthesis stages. Leaf water potential, leaf osmotic potential and leaf turgor potential (measured with pressure chamber and osmometer), as well as leaf diffusive resistance, leaf transpiration rate and leaf‐to‐air transpiration gradient (measured with a steady‐state porometer) were measured diurnally. Growth and yield parameters were recorded after harvesting of the crop. Triplicate data were analysed using a completely randomized design and correlations amongst these parameters were computed. Water stress was found to reduce diurnal leaf water potential and leaf osmotic potential in both the genotypes but leaf osmotic potential was significantly higher in the drought‐tolerant cultivar C‐306 than in the drought‐sensitive cultivar Kalyansona. Positive turgor was recorded in both the genotypes under water stress and non‐stress conditions. Water‐stressed plants showed significantly lower turgor potential than control plants. In diurnal observations, water‐stressed plants exhibited significantly higher leaf diffusive resistance in both genotypes at both stages. The diffusive resistance of C‐306 was predominantly higher than that of Kalyansona. Water stress decreased leaf transpiration rate at both stages but the reduction was higher at the anthesis stage. The leaf‐to‐air temperature gradient was much higher in C‐306 than in Kalyansona at the boot stage but at the anthesis stage genotypic variation was non‐significant. The capacity to maintain cooler foliage was lower at the anthesis stage than at the boot stage in both the cultivars. Shoot dry weight, number of grains, test weight, grain yield, biological yield and harvest index decreased to a greater extent when water stress was imposed at the anthesis stage, while imposition of water stress at the boot stage caused a greater reduction in plant height and number of tillers. Similarly, water stress caused a smaller reduction in growth, yield and yield attributes in C‐306 than in Kalyansona. In general, the correlation coefficient of grain and biological yield with water potential and its components was positive and highly significant. Similarly, turgor potential was also correlated positively and significantly with grain yield at both the stages, but with biological yield it was significant only at the anthesis stage. A negative and significant correlation was obtained for diffusive resistance and leaf‐to‐air temperature gradient with grain yield at the boot and anthesis stages. The rate of transpiration was also positively and significantly correlated to grain and biological yields at both the stages. Amongst the yield attributes, number of leaves and number of tillers were positively correlated at the anthesis stage, whereas leaf area and shoot dry weight were significantly correlated with grain and biological yields at both the stages.     

土壤水分胁迫对冬小麦耗水规律及产量的影响

在温定盆栽和池栽防雨旱棚条件下，研究了土壤水胁迫对冬小麦耗水规律及产量的影响，结果表明，随土壤水分胁迫加剧，干物质积累减少，子粒千物质来自贮藏同化物的比例上升，产量下降，产量构成三因子中穗粒数，亩穗数下降均极显著，而千粒重下降较少，随水分胁迫加剧，拔节前耗水量占总耗水量的比率增高，从播种到拔节期，耗水量占总耗水量的比例愈高，拔节后植株衰老死亡愈早，产量降低就愈大，中度水分胁迫下，虽然水分生产率和经     

水分胁迫效应对冬小麦生长发育的影响研究

利用温室管栽试验，研究水分胁迫效应对冬小麦生长发育的影响。结果表明：苗期水分胁迫，拔节期与开花期复水能激发冬小麦根、茎、叶、冠生物量显著增长，三叶至分蘖期控水的处理绿叶面积日增量最大；前期一直干旱灌浆期复水能明显减缓植株的衰老速率。冬小麦前期经受中度或重度水分胁迫，拔节期复水后增产效果最大，前期经受中度水分胁迫，开花期复水后水分利用效率最高。确定土壤含水量占田间持水量55％为冬小麦分蘖期水分胁迫效应增产节水的水分临界指标。     

水分胁迫对冬小麦干物质分配的影响

试验采用盆栽方法,通过设置不同的土壤水分条件,研究不同土壤水分对冬小麦生长发育的影响,从器官水平上考察了水分条件对冬小麦物质积累、分配等的影响,并建立了产量和耗水量的关系方程。在水分适宜条件下,茎杆所占比例较小,为32%,穗部占39%,而过度灌溉和严重水分胁迫条件下,茎杆所占比例较大,分别为43%和34%,穗部所占比例较小,仅为41%和27%。在不同等级水分条件下,均以茎杆对产量的贡献最大。相对适宜的土壤水分条件(70%~60%)时,茎杆对产量的贡献最大,为0.97 g/茎,水分胁迫严重条件下,叶片对冬小麦产量贡献比适宜土壤水分条件时的叶片贡献要大一些,为0.79 g/茎。根据试验产量和耗水量回归分析表明,泰安地区在现有的肥水水平和栽培技术条件下,冬小麦的理论最大产量为0.62 kg/m2,耗水量702.35 mm,最高水分利用率17.65%,冬小麦在拔节至扬花浇水显得尤为重要,生产上应特别注意加强扬花水、灌浆期水分管理。     

冬小麦若干品质性状遗传及相关的研究

F_1的沉淀值、伯尔辛克值介于双亲之间,前者以正向部分显性为主,后者以负向部分显性为主,与中亲值相关显蔟,遗传力高,表明这两个性状在杂交后代易于获得遗传进展。相反,蛋白含量在 F_1出现了各种类型的表现,很难指出以哪种遗传形式为主,与中亲值无显著相关,遗传力低,表明高蛋白育种较难。但在 F_2、F_3中各组合都出现了蛋白含     

水分胁迫条件下有机肥对小麦根苗生长的影响

水分胁迫条件下施用有机肥对小麦根苗生长的影响研究表明：随着水分胁迫程度的加剧,无论施肥与否,小麦根系均表现出根重下降、根长缩短、根活力降低、次生根数与根系吸收面积减小、根系SOD、POD活性明显降低、MDA含量和根冠比明显增高的趋势。但施有机肥促进小麦根系的生长,改善根系生理特性,增加根系吸收面积和活力,具以肥促根、以肥调水、延缓根系衰老的作用。有机肥和土壤水分对小麦产量的增加具有明显的正交互作用,特别是在小麦生长中心发生转换的关键时期,即拔节期,水肥的显著互作促进根系的生长,在一定程度上缓解干旱胁迫的影响,最终导致土壤水分利用率的提高和产量的增加。     

土壤水份胁迫对冬小麦光合及产量的影响

在池栽防雨旱棚条件下研究了土壤水分胁迫对冬小麦光合及产量的影响。结果表明，随土壤水分胁迫加剧，小麦旗叶光合速率下降，气孔导度降低，籽粒灌浆速率下降，从而导致产量降低；但是，轻度胁迫与水分适宜处理之间，上述生理特性和籽粒产量均无显著差异，这就为节水高产提供了理论依据。     

Indices of Drought Tolerance in Wheat Genotypes at Early Stages of Plant Growth

Thirty diverse genotypes of bread wheat were evaluated for seed vigour index, germination percentage, root length, shoot length, root‐to‐shoot length ratio, coleoptile length and osmotic membrane stability under laboratory conditions. Considerable variation was observed for all the characters. Discrimination among the genotypes on the basis of mean values was better under normal than under moisture stress conditions, indicating suppression of variability under moisture stress conditions. Comparison of mean performance under normal and osmotic stress conditions indicated that the seed vigour index was the most sensitive trait, followed by shoot length, germination percentage and root length. The root‐to‐shoot length ratio, however, increased under osmotic stress. The magnitude of genetic components of variance and heritability were, in general, lower under osmotic stress than under normal conditions. All the characters except germination percentage, shoot length and coleoptile length showed considerable genetic variability. Heritability in the broad sense was also moderate to high for all the characters under both environments. Due to high heritability and genetic advance great benefit from selection can be expected for the osmotic membrane stability of leaf segments and root‐to‐shoot length ratio. Moderate progress can be expected from root length and seed vigour index. Correlation studies indicated that the osmotic membrane stability of the leaf segment was the most important trait, followed by root‐to‐shoot ratio and root length on the basis of their relationships with other traits.     

干旱胁迫对不同冬小麦品种幼苗期生理特性的影响

研究小麦幼苗时期生理指标等方面的抗旱特性,为今后抗旱小麦新品种的培育提供基础的理论依据。选用5个肥水类型不同的小麦品种,在20% PEG-6000(w/v)水分胁迫条件下,研究不同冬小麦品种幼苗时期的生理抗旱特性,并对幼苗期抗旱生理指标与抗旱指数做了相关性分析。结果表明,在20%的PEG-6000(w/v)渗透胁迫后,5个小麦品种渗透调节物质可溶性糖和脯氨酸含量均上升,且上升的程度与抗旱性一致;胁迫条件下保护酶系统SOD和POD活性均降低,其中POD活性呈先上升后降低的趋势;膜脂过氧化产物MDA含量升高。与高肥水品种相比,‘青麦7号’和‘鲁麦21’的可溶性糖和脯氨酸含量较高,随胁迫时间延长增加的幅度大;MDA含量积累的速度以及SOD、POD活性降低的速度较为缓慢。其中,可溶性糖含量、脯氨酸含量、SOD活性以及POD活性与抗旱性鉴定指标抗旱指数存在极显著相关性,可以作为小麦抗旱性鉴定的早期生理指标。     

Effect of Simulating Drought in Various Phenophases on the Water Use Efficiency of Winter Wheat

In Central Europe, drought is the most important limiting factor for autumn‐sown cereals. Due to the decline in groundwater, it is a priority to use less water‐demanding forms of crop production. Water use efficiency (WUE) can only be increased if cultivars with satisfactory water management traits are grown, so that they can exploit the water reserves of the soil even if drought occurs during the vegetation. Water consumption and water use efficiency of winter wheat genotypes were investigated in a model experiment carried out in a climate‐controlled glasshouse. The plants were grown either with optimum water supplies or with simulated drought in three phenophases, and measurements were made on the yield parameters, phenological traits and water use parameters of the plants. Substantial differences were observed between the water demands of the cultivars, and it was found that the later the phenophase in which drought was simulated, the greater the decline in water uptake. The analysis of WUE led to the conclusion that the WUE values of cultivars with short vegetation periods dropped to the greatest extent when water deficit was suffered at first node appearance, while cultivars with longer vegetation periods were more sensitive to drought during the heading and grain‐filling stages.     

土壤水分胁迫对冬小麦叶片渗透调节及叶绿体超微结构的影响

土壤水分胁迫下 ,抗旱性强的小麦品种昌乐 5号、北农 2号与抗旱性弱的济南 13、鲁麦 5号相比 ,渗透调节能力高 0 4 1～ 0 60MPa ,相对含水量少降 6 39～ 10 74个百分点 ,叶水势少降 0 19～ 0 63MPa。水分胁迫使小麦叶片光合能力下降 ,水分胁迫全过程下降平均百分数 ,抗旱性强的品种比抗旱性弱的品种光合速率少降 17 7%～ 2 2 5% ;气孔导度少降 2 1 0 6%～2 3 75%。小麦叶肉细胞叶绿体的超微结构发生变化且随水分胁迫的加重而加剧 ,但变化程度与小麦的抗旱性及渗透调节能力成负相关。胁迫导致叶绿体外形变圆 ,类囊体肿胀 ,片层间距加大 ,基质片层模糊 ,最终叶绿体解体     

水氮胁迫对冬小麦籽粒灌浆速率影响的模拟研究

为定量分析水氮胁迫对冬小麦籽粒灌浆速率的影响,以‘济麦22’为材料,于2016—2017和2017—2018年度开展施氮试验。结合2017—2018年度试验资料,通过分析水氮胁迫对冬小麦籽粒灌浆速率的影响规律,引入氮素和水分影响因子,构建水氮胁迫对冬小麦籽粒灌浆速率影响的模拟模型S_(j,t)=S_(W3N300,t)×(1+F_N)×(1+F_W)。经2016—2017年小麦生长数据检验,除绝对误差占实测值比率d_ap略高外,RMSE值、平均绝对误差d_a以及相关系数r均显示模拟值和实测值有较高的一致性,说明实测值与模拟值吻合程度较好,所建模型可较好模拟水氮胁迫对冬小麦籽粒灌浆速率的影响。     

土壤水分对冬小麦生长后期光能利用及水分利用效率的影响

通过控制不同土壤水分条件形成不同的小麦（Triticum aestivum L.）群体结构,测定了抽穗到成熟期间小麦冠层光合有效辐射（PAR）截获及垂直分布、干物质积累和产量。研究表明,不同处理小麦冠层对PAR的截获量差异较小（小于15.7%）,但冠层上部（60~80 cm）的PAR截获量和生长后期PAR转化效率差异明显（100.7%和63.7%）,与产量和光能利用效率变化一致,可见土壤水分是通过改变小麦群体内PAR垂直分布及PAR转化效率对作物产量和光能利用效率产生影响。抽穗到成熟期间维持小麦冠层上部PAR截获率在50%左右是实现高产的重要保证。随着土壤水分改善,冬小麦光能利用率和产量持续增加,但水分利用效率却先于二者提前降低,说明改善水分利用效率是提高华北地区农业气候资源利用效率的关键。在底墒充足的条件下,分别在拔节和挑旗期灌水60 mm可获得较高的光能和水分利用效率及经济产量     

遥感信息应用于水分胁迫条件下的华北冬小麦生长模拟研究

由于初始土壤水分、灌溉量等变量的空间分布不易获得,区域尺度水分胁迫条件下作物生长模拟存在一定难度。本文在WOFOST模型本地化和区域化的基础上,采用调控型方法,重点探讨了利用MODIS数据反演的地表蒸散在大范围内估算土壤水分平衡过程中的参数或变量初始值,以实现水分胁迫条件下作物模型区域模拟的可行性。2002年模拟结果显示,引入遥感信息优化获得初始土壤有效含水量、返青期生物量及抽穗期灌溉量后,土壤水分的模拟效果得到改善;32个农业气象试验站点模拟产量的相对均方根误差（RRMSE）由0.63降至0.20;华北冬小麦模拟产量的空间分布与实际产量分布更加接近,产量低估的情况得到较好改善;河北、河南、山东3省平均产量的模拟误差分别为－4.9%、4.3%和8.6%。初步结果表明,结合卫星遥感信息通过优化方法在大范围内估算作物模型的相关参变量,以实现水分胁迫条件下作物模型的区域应用是行之有效的。     

小麦胚芽对面包品质的研究

为了提高小麦胚芽的开发利用价值,将经过脱脂的麦胚粉按不同比例添加到面包面团中,通过测定面包的比容、内部硬度及黏附性和进行面包的感官品质评定,确定既能提高面包营养价值又不对面包品质有所影响的最适添加量。经测定结果分析,麦胚粉的最适添加量为3%。     

水分胁迫对不同抗旱性冬小麦愈伤组织的影响

比较了不同强度的水分胁迫对两个抗旱性不同的小麦品种－花８４（抗旱）和冀麦３４）不抗旱）的幼胚愈伤组织的影响,分析了其生理把就差异以及与抗旱性的关系。结果表明,经２４h胁迫后两品种的膜透性均增大,冀麦２４大小花８４;花８４的愈伤组织经胁迫后,游离脯氨酸含是市于冀麦２４;二者ＰＯＤ活性随胁迫强度的加重都迅速提高,但冀麦２４增幅较市,以ＴＴＣ还原力测定细胞活力,发现两品种ＴＴＣ还原力都下降,但花８４较冀麦２４降低幅度小,另外,花８４细胞的蛋白质抗ＰＥＧ沉淀能力强,能在水分胁迫政保持较为正常的功能。     

水分亏缺条件下冬小麦几个抗旱性状的应用价值

在盆栽水分亏缺条件下,以15个抗旱性不同的冬小麦品种(系)为材料,对其8个抗旱性状的应用价值进行了研究.结果表明,通过乳熟期旗叶气孔阻力和蒸腾速率、两种用水效率(分别用干重和粒重表示)对单株粒重进行选择,其效率比通过3个农艺性状(单株干重、株高、顶部3叶总面积)的要低得多,说明前者在抗旱育种中的应用价值不大.     

水分胁迫对冬小麦愈伤组织的影响

利用抗旱性不同的32个冬小麦品种的成熟胚、幼穗和幼胚产生的愈伤组织作为供试材料,以聚乙二醇(PEG)诱导的渗透压模拟水分胁迫,测定了游离脯氨酸含量、相对含水量、组织活性及渗透势值。实验结果表明,在水分胁迫下,供试愈伤组织的游离脯氨酸含量增加,相对含水量、组织活性及渗透势值表现下降。聚类分析的结果表明,冬小麦在整株水平与细胞水平之间对于水分胁迫存在着一致性。     

不同的抑制剂处理对水分胁迫诱导的冬小麦幼苗ABA累积的影响

研究了不同放线菌素Ｄ（ＡＭＤ）及环己亚胺（ＣＨＭ）处理方法对水分胁迫诱导的冬小麦幼苗内源脱落酸（ＡＢＡ）累积的影响。结果表明，在水分胁迫下，植物体根及叶片中ＡＢＡ随着水分胁迫时间的延长而增加，根ＡＢＡ增加早于叶片ＡＢＡ增加。在ＡＭＤ和ＣＨＭ与ＰＥＧ的３种处理后，ＡＭＤ和ＣＨＭ与ＰＥＧ同时处理根对于由胁迫诱导的根及叶片中ＡＢＡ增加具有明显的抑制作用。