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1.
Conversion from annual bluegrass or bentgrasses to red fescue could be an efficient way to minimise water use on golf greens. Our objective was to investigate the influences of four irrigation strategies on red fescue water use efficiency, turf quality, growth rate and resistance to annual bluegrass and moss invasion. The trial was carried out from August 2013 to August 2015 on a green established according to USGA recommendations under a rainout shelter at Landvik, Norway (58 °N). On average for 2 years, irrigation to field capacity once per week (FC 1) and deficit irrigation to 60% of FC three times per week (DEF 3) reduced the water consumption by 49% and 72% relative to irrigation to FC three times per week (FC 3). Both DEF 3 and FC 1 retained acceptable turf quality and reduced annual bluegrass in the second year by about one‐third. Better control of annual bluegrass was obtained with deficit irrigation to 60% of FC once per week (DEF 1), but this treatment did not produce acceptable turf quality. Compared with FC 3, DEF 3, FC 1 and DEF 1 gave harder surfaces and reduced the moss invasion in the second year by 66%, 90% and 93%, respectively. Irrigation effects on root development and thatch organic matter after 2 years were not significant, although the thatch layer depth was 3–4 mm greater in FC 1 than in the other treatments. In conclusion, DEF 3 and FC 1 are both effective irrigation strategies for managing red fescue greens with less water use.  相似文献   

2.
A field trial conducted on the melon cultivar Huanghemi irrigated with saline water was carried out in Minqin County in the 2‐year period, 2007 and 2008. In three irrigation treatments, different saline water concentrations were applied, that is 0.8 g l?1 (Control C), 2 g l?1 (Treatment S1) and 5 g l?1 (Treatment S2), reproducing the natural groundwater concentration in the county. The electrical conductivity of the saline water was as follows: 1.00, 2.66 and 7.03 dS m?1, respectively. The aims of the study were (i) to monitor water consumption and water potential, (ii) assess, during the whole crop cycle, some growth parameters and their relations for estimating the morpho‐functional plant response irrigated with saline water and (iii) determine the ion concentration in different plant tissues to evaluate which mechanism the plant activates in the presence of high salt concentrations. Under salinity stress, the plants sustained the concentration of Ca, Mg and K, but at a level not sufficient to limit the Na adsorption. Therefore, the melon yield decreased and it was determined by a displacement of the ratio K/Na and by a lower (total potential MPa). Consequently with increasing salinity, a significant reduction was observed in: water consumption (ET c, mm), leaf area duration (LAD, m2 d), on shoot dry weight aboveground (W , g plant?1), on specific leaf area (SLA, cm2 g?1) and on leaf area ratio (LAR, cm2 g?1). In treatment S2, in addition to these changes which mainly affected the plant morphology with effects on the biomass produced, a moderate reduction was also observed in net assimilation rate (NAR, g m?2 d?1), water use efficiency (WUE), a significant reduction in the energy conversion efficiency (ECE, %) and, in short, in a reduction in the relative growth rate (RGR, g g?1 d?1).  相似文献   

3.
蒋影  苏德荣 《中国农学通报》2011,27(12):172-176
种子吸收一定量的水分后能够正常发芽,在这个过程中,种子将消耗外部环境的水分,这种改变将影响种子对水分的吸收,并最终导致种子的发芽率不同。试验以三种草坪草为研究对象,通过限定灌水量来模拟地下滴灌方式,讨论了10个水分梯度下种子吸胀吸水和萌发的变化情况。结果表明,在灌水量不同的情况下,萌发前外部环境水分变化率差异显著,但当灌水量超过60%时,差异不显著;种子开始萌发后,萌发初期种子发芽较快,然后逐渐变慢,最终达到稳定状态,当灌水量达到一定值时,累计发芽率达到最大值,但当水分含量超过这一定值时,反而会抑制种子的发芽,其中多年生黑麦草种子对水分最敏感,能最快达到最大发芽率,而草地早熟禾对水分反应不敏感,则最慢达到最大发芽率。研究结果可用于描述种子发芽过程中外部水分变化与发芽率的关系,并有助于种子发芽最优水量的确定和提高水分的利用效率。  相似文献   

4.
Two chilling‐tolerant genotypes, that is, weedy rice WR03‐45 and cultivated rice Lijiangxintuanheigu and two chilling‐sensitive genotypes, that is, weedy rice WR03‐26 and cultivated rice Xiuzinuo were used in this study to investigate the effects of exogenous abscisic acid (ABA) on protection against chilling damage as well as on changes in physiological features. The results showed that under chilling stress the increased levels of superoxide radical (), hydrogen peroxide (H2O2) and malondialdehyde (MDA) in WR03‐45 and Lijiangxintuanheigu were lower than those in WR03‐26 and Xiuzinuo. Activities of antioxidant enzymes (superoxide dismutase (SOD), catalase (CAT), ascorbate peroxidase (APX), glutathione reductase (GR)) and non‐enzymatic antioxidants (ascorbate acid (AsA) and reduced glutathione (GSH)) were enhanced in WR03‐45 and Lijiangxintuanheigu, whereas they were decreased significantly in WR03‐26 and Xiuzinuo. Application of exogenous ABA reduced the chilling damage in the four genotypes. The pre‐treatment with ABA decreased the levels of , H2O2 and MDA caused by chilling stress in the four genotypes through increasing the activities of SOD, CAT, APX, GR and the contents of AsA and GSH in the four genotypes under chilling stress. Moreover, pre‐treatment with Fluridone, the ABA biosynthesis inhibitor, prohibited the effects of ABA through enhancing the oxidative damages and suppressing the antioxidant defence systems under chilling stress. The results indicate the mechanism for rice with chilling tolerance is to enhance the capacity of antioxidant defence systems under chilling stress. Furthermore, ABA plays important roles in the tolerance of rice against chilling stress for it could induce the capacity of whole antioxidant defence systems including enzymatic and non‐enzymatic constitutions under chilling stress.  相似文献   

5.
We investigated the leaf : stem partitioning of winter wheat (Triticum aestivum L. varieties ‘Dekan’ and ‘Batis’) with and without drought influence. Irrigated and drought‐stressed winter wheat, grown in a rainout shelter in 2009/10 and 2013/14, were sampled during shoot elongation phase at the experimental Farm Hohenschulen located in Northern Germany. The data set contains leaf (DML) and stem dry masses (DMS), as well as measured water contents for several soil layers. A reduced relative dry matter allocation to leaves was observed under drought stress. Our results clearly show that, if simulated leaf : stem partitioning is not sensitive to drought, this will cause a positive bias in simulated leaf and a negative bias in simulated stem dry matter under water‐limited conditions. This is in accordance with previous studies which revealed that crop simulators often overestimate the impact of drought on light‐use efficiency, whereas the consequences on leaf area development are underestimated. However, the drought stress‐induced shift in leaf : stem partitioning is yet not considered by most common wheat crop simulators. Our aim was to fill the gap in simulation of drought stress implications on leaf area development. A simple allometric model for leaf : stem partitioning () was parameterized. Starting from the allometric leaf : stem relationship observed under optimum water supply, a correction term was introduced, which allows to adapt the partitioning to drought stress conditions. The lg‐transformed root‐weighted soil water potential in the rooting zone (lgψroot, lg(hPa)), calculated as a function of measured water contents and simulated root distribution, was used as a drought stress indicator. The linear correction term assumes an increase of the stem fraction, proportional to the difference between lgψroot and a drought stress threshold (pFcrit, lg(hPa)). The analysis revealed that the shift in allometric partitioning towards stem fraction starts with lgψroot greater than 1.92 [lg(hPa)]. The slope of the relative increase of dry matter allocated to the stem fraction was determined with 0.26 [lg(hPa)?1]. Both parameters of the correction term were found to be highly significant. Implications for crop modelling are discussed.  相似文献   

6.
为了明确生根剂GGR-6对植物生长与抗旱性的生理作用,以2种优质草坪草-紫羊茅‘梦神’(Festuca rubra ‘Rubra’)、草地早熟禾‘优异’(Poa pratensis ‘Merit’)为供试材料,通过控水的处理方法,分别在播种后不同时期,用不同浓度的GGR-6对2种草坪草进行浇灌。结果表明：随着干旱胁迫的进行,紫羊茅和早熟禾的抗氧化酶活性呈现先增加后降低的趋势,同时游离脯氨酸含量增加,以维持渗透平衡,叶片MDA含量保持在较低的水平。早熟禾的抗旱能力高于紫羊茅。浇灌GGR-6对2种草坪草幼苗的生长有明显的促进作用,并可以提高其抗旱能力。其中,紫羊茅于播种后1周浇灌低浓度(0.1 g/L、0.2 g/L)的GGR-6效果较好;早熟禾于播种2周后浇灌低浓度(0.1 g/L、0.2 g/L)的GGR-6,播种3周后浇灌高浓度(0.3 g/L)的GGR-6效果较好。研究结果证实GGR-6对提高植物耐旱性具有重要作用,并为利用外源物质提高植物抗逆性提供一定的科学依据。  相似文献   

7.
Low temperature seriously depresses seed germination and seedling growth in winter wheat (Triticum aestivum L.). In this study, wheat plants were sprayed with abscisic acid (ABA) and fluridone (inhibitor of ABA biosynthesis) at 19 days after anthesis (DAA) and repeated at 26 DAA. The seeds of those plants were harvested, and seed germination and offspring's seedling growth under low temperature were evaluated. The results showed that exogenous ABA application decreased seed weight and slightly reduced seed set and seed number per spike. Under low temperature, seeds from ABA‐treated plants showed reduced germination rate, germination index, growth of radicle and coleoptile, amylase activity and depressed starch degradation as compared with seeds from non‐ABA‐treated plants; however, activities of the antioxidant enzymes in both germinating seeds and seedling were enhanced from those exposed to exogenous ABA, resulting in much lowered malondialdehyde (MDA) and H2O2 concentrations and production rate. In addition, the maximum quantum efficiency of photosystem II was also enhanced in ABA‐treated offspring's seedlings. It is concluded that exogenous ABA treatment at later grain‐filling stage could be an effective approach to improve cold tolerance of the offspring during seed germinating and seedlings establishment in winter wheat.  相似文献   

8.
在温室土壤-作物-环境的连续体中,作物水分损耗、吸收和水分利用效率一直是研究的热点,温室作物水分来源的唯一途径是灌溉。为了在生产实践中指导节水灌溉,从近些年来节水灌溉的新技术新方法--滴灌和调亏灌溉入手,主要综述了温室内作物调亏灌溉的研究,包括调亏灌溉的节水及增产机理,调亏灌溉相应的灌溉指标,影响调亏灌溉的环境因素,以及作物本身不同时期对水分亏缺的反应。  相似文献   

9.
为明确合理密植条件下调亏灌溉的节水增产效果,在新疆干旱区大田研究了灌溉量(饱和灌溉、正常灌溉、调亏灌溉)和种植密度(12万、18万、24万株·hm-2)对棉花生长发育和产量品质的影响。结果表明,灌溉量和种植密度对棉花生物产量、经济系数、经济产量有显著的互作效应,但对纤维品质没有影响。调亏灌溉显著抑制营养生长,但提高了收获指数;调亏灌溉下适当提高密度,显著提高了生物产量和单位面积铃数。调亏灌溉下高密度处理组合在用水量减少20%的情况下,棉花产量与正常灌溉下中、高密度以及饱和灌溉下低密度等高产组合的产量相当。调亏灌溉配合合理密植是旱区棉花节水增产的有效栽培途径之一。  相似文献   

10.
Polyamines (PAs) are ubiquitous biogenic amines that play important roles in the environmental stress tolerance of crops. However, the relationship between PAs and plant waterlogging (WL) tolerance has received little attention. In this study, the protective effects of spermidine (Spd) against WL stress were investigated by Zea mays. WL treatment inhibited root growth and caused a significant increase in lipid peroxidation, membrane permeability and DNA damage in maize roots. Pre‐soaking seeds with Spd markedly alleviated these effects caused by WL. Spd pre‐soaking also significantly increased the endogenous Spd content in both control and waterlogged maize roots. In addition, the activity of antioxidant enzymes (catalase, CAT; glutathione reductase, GR; superoxide dismutase, SOD; peroxidase, POD) was enhanced in Spd‐pre‐soaked maize roots under WL stress. Thus, hydrogen peroxide (H2O2) and superoxide‐radical () accumulation were reduced. Spd treatment also enhances the expression and protein abundance of heat shock protein (HSP) 70 and 90 during the period of WL stress. Furthermore, Spd pre‐soaking reversed the inhibition effect of WL on H+ efflux and K+ influx in maize roots. The PM H+‐ATPase activity in Spd‐pre‐treated seedlings exhibited less inhibitory under WL conditions. In conclusion, this study suggests that WL stress could be alleviated by priming seeds with Spd in maize species. This alleviative effect was partially attributable to (i) up‐regulated activity of antioxidant enzymes; (ii) maintained PM H+‐ATPase activity; and (iii) increased Hsp70 and Hsp90 gene expression and protein abundance.  相似文献   

11.
Summary Hemp cultivation is not new to the southern regions, but cultivated area is decreasing. Recently, there has been a rediscovery of this crop, as a result of requests from the producers of natural fibres.The paper synthesizes the studies recently set up in southern Italy, with the goal of evaluating the adaptation and the yield of recent genotypes and of new agronomic techniques. The study demonstrates that, with the exception of the monoicious cultivars, the new genotypes of hemp are adapted to the environmental conditions of the Mediterranean Europe, reaching productive standards not lower than those obtained in other environments.The use of irrigation is indispensable for overcoming the prolonged water deficit which hemp is subject to during its cultivation cycle. A good irrigation practice consists in the partial satisfaction of the water requirements. The experimental evidence indicates that the best productive results are obtained with the reintegration of 66% of the water lost through evapotranspiration.A further saving in water is obtained with the anticipation of the sowing period, with, however, a loss in productive potential.Hemp can be considered, in all respects, a species to reintroduce in the current cultivation systems of southern Europe. It will be possible to increase its potential provided that breeding supplied new varieties, more tolerant to low temperatures (in order to anticipate the sowing time), and able to obtain economically profitable yields with the use of limited irrigation.  相似文献   

12.
A 3‐year study was conducted at New Mexico State University in Las Cruces, NM, to investigate the effects of different fertilization treatments on turf performance when water conservation strategies are applied. These strategies include the use of non‐potable saline irrigation water and the use of efficient subsurface irrigation systems. Two low water use warm‐season grasses, “Princess 77” bermudagrass (Cynodon dactylon L.) and “Sea Spray” seashore paspalum (Paspalum vaginatum O. Swartz), were irrigated with either potable [Electrical Conductivity (EC) = 0.6 dS/m] or saline (EC = 3.1 dS/m) water from either an overhead or a subsurface drip irrigation (SDI) system. Four different fertilizers, liquid slow release, granular slow release, granular urea and liquid urea, were applied at two rates: 10 and 20 g N m?2 year?1 for “Sea Spray” and 20 and 30 g N m?2 year?1 for “Princess 77.” Spring green‐up, summer quality and fall colour retention were determined using digital image analysis, visual quality ratings and normalized difference vegetation index. Generally, subsurface drip‐irrigated grasses were slower to green‐up than overhead irrigated ones. “Sea Spray” irrigated from the SDI system took 18, 28 and 15 days longer to reach 80% green cover in 2010, 2011 and 2012, respectively, than their sprinkler‐irrigated counterparts. The combination of “Princess 77” and overhead irrigation reached 80% green cover 35 (in 2010), 34 (in 2011) and 12 (in 2012) days faster than SDI‐irrigated “Princess 77.” Fertilization rate and type had no effect on summer turfgrass quality of “Princess 77” irrigated from a sprinkler system throughout the research period reaching ratings of greater than 7 during all 3 years. Similar results were observed for “Princess 77” irrigated from a SDI system during 2010 and 2011. Summer quality of sprinkler‐irrigated “Sea Spray” was negatively affected by liquid fertilization. During two of three summers, visual quality of plots fertilized with either liquid slow release or liquid urea was lower than “Sea Spray” fertilized with granular fertilizer. Further research is needed to investigate the effect of fertilization on bermudagrass and seashore paspalum over a wider nitrogen range including both granular and foliar products.  相似文献   

13.
为给马铃薯滴灌研究领域的学术、科研人员提供参考依据,本研究从马铃薯需水规律出发,总结了不同灌溉制度对滴灌条件下马铃薯生长发育及光合作用的影响,归纳了不同灌溉制度对马铃薯产量及品质的影响。发现马铃薯研究存在结论精确度不高、缺乏准确性和时效性、大部分地区滴灌技术与农艺栽培技术配套不完善的问题。提出今后研究可以从不同灌溉制度下马铃薯耗水规律及品质的差异、精准农业及马铃薯单产和成本的模拟研究入手。  相似文献   

14.
为民勤干旱沙区红枣栽培探索科学合理的灌溉制度,以4年生密植骏枣为研究对象,通过田间试验,研究生育期滴灌条件下充足灌水、80%轻度调亏、60%中度调亏和40%重度调亏4种灌溉措施对枣树生长和产量的影响。结果表明：在民勤干旱沙区,供水量在425.7~545.7 mm之间枣树均能正常生长,株高、新梢长和茎粗增量均随着灌水量的增加而增大;轻度调亏灌溉可提高骏枣果实的纵、横径和单果质量,产量增加7.8%,水分利用效率提高16.3%。采取轻度调亏灌溉措施可以有效提高民勤干旱沙区枣树产量和水分利用效率。  相似文献   

15.
不同灌水方式淋洗下滨海盐土的水盐运移特征   总被引：2，自引：1，他引：1  
为了合理有效地利用水资源,快速改良滨海盐土,通过室内土柱试验探讨了不同灌水方式淋洗下滨海盐土的水盐运移特征。结果表明：咸水的入渗速率要明显高于咸淡交替和淡水入渗。在灌水淋洗后,土壤盐分含量均大幅下降,以先用咸水再用淡水灌水淋洗方式脱盐效果最好,脱盐速度最快,淡水淋洗方式脱盐速度最慢。脱盐后,3个处理土壤的pH值均上升,淡水淋洗土壤pH上升幅度最大,先咸后淡灌水淋洗土壤pH上升幅度最小。采用先咸后淡灌水方式淋洗滨海盐土的综合效果最好,为淡水资源短缺,咸水资源丰富的盐碱地区的盐土淋盐改良提供了科学的方法。  相似文献   

16.
Abstract The objective was to study soil water conservation and physiological growth of wheat (Triticum aestivum L.) using composted cattle manure applied either as mulch or incorporated with soil at 20 Mg ha?1. Haruhikari, a relatively drought‐sensitive and Hongmangmai, a relatively drought‐tolerant wheat, were the cultivars studied under both adequate and deficit irrigation. Fourteen weeks after sowing (WAS), the number of tillers and leaves was significantly reduced by 19 % and 30 % respectively under deficit irrigation and Hongmangmai produced slightly (10 %) more tillers than Haruhikari. Unlike mulching, the incorporation of manure had favourable effects on plants in terms of shoot dry mass (SDM) by 36 % and number of tillers and leaves by 40 %. Haruhikari produced substantially (29 %) greater root mass under adequate irrigation but Hongmangmai produced slightly (2.7 %) more roots and responded much better to manure use whether under adequate or deficit irrigation. As a result, Hongmangmai suffered less severe reductions in tillers and biomass under water stress. In comparison, the mulched manure treatment saved 15 % and 64 % respectively more water than the control and the treatment incorporating manure, but this advantage in water‐saving did not translate to superior plant growth. Leaf water potential (ψl) under adequate irrigation significantly exceeded that under deficit irrigation by 27 % and the ψl of Haruhikari exceeded that of Hongmangmai by 15 %. However, Hongmangmai may be considered more tolerant of dehydration since it maintained much higher net photosynthetic rates (PN) even with a lower leaf water potential. The reduction in the PN and intracellular carbon dioxide concentration (Ci) of the cultivars under deficit irrigation was on account of decreasing stomatal conductance (gs) and transpiration rate but on average, the gs of Hongmangmai significantly exceeded that of Haruhikari by as much as 0.53 under adequate irrigation and 0.22 under deficit irrigation. In conclusion, we suggest that the drought tolerance of Hongmangmai was related to its superior root growth and greater ability than Haruhikari, to efficiently utilize incorporated manure for growth under water stress.  相似文献   

17.
为探究缓/控释肥在不同水分条件下提高氮素利用率及增产机制。本研究以杂交中稻F优498为试验材料,在180 kg hm-2施氮量基础上,采用两因素裂区设计: 主区设控灌、干湿交替灌溉、传统灌水灌溉3种水分管理方式,副区设尿素一道清、尿素常规运筹、硫包膜缓释肥、树脂包膜控释肥4种氮肥种类,研究缓/控释肥和水分管理方式对水稻干物质量和氮素吸收、运转、分配和产量的影响及其互作效应。结果表明, 缓/控释肥和水分管理方式对水稻主要生育期干物质量和氮吸收、转运、分配及产量具显著影响及互作效应,产量构成因素与氮素在结实期转运总量及其分配呈显著正相关。干湿交替灌溉和缓/控释肥均能提高干物质量、氮素吸收及产量并表现出显著互作效应,施用缓/控释肥氮素表观利用率达42%~53%,相较于尿素一道清和传统的尿素常规运筹,氮肥偏生产力提高6%~23%,氮素农学利用率提高26%~71%,增产8%~19%。控灌条件下,缓/控释肥处理氮素有效性高,保证足穗、促进重穗;干湿交替灌溉条件下缓/控释肥处理能保持氮素的高效释放,有利于高产群体的形成,从而提高稻株氮素积累、协调氮素分配;淹水灌溉条件下,缓/控释肥处理无效分蘖减少,氮素入渗、淋溶降低,成穗率提高。综合产量与氮素吸收、运转的表现,干湿交替灌溉条件下施用缓控释肥为本试验最佳处理,能有效提高氮素利用率,促进高产形成。  相似文献   

18.
  相似文献   

19.
为测定膜下滴灌调亏马铃薯全生育期内不同调亏水平土壤养分、土壤水热动态、生长动态、产量效应和水分利用效率,于2016年在河西荒漠绿洲灌区民乐县益民灌溉试验站开展了马铃薯不同生育阶段水分调亏灌溉的试验研究,结果表明,马铃薯膜下滴灌调亏土壤水热变化均匀且利用率高,有利于马铃薯对土壤养分的充分吸收和利用;土壤养分是土壤肥力的核心,是植物在生长发育过程中不可或缺的重要因素,膜下滴灌调亏栽培能有效减少土壤速效养分的流失,并提高马铃薯对土壤速效养分的利用效率;不同生育阶段马铃薯耗水量受水分调亏程度影响较大,其耗水量随调亏程度增大而显著减少(P0.05),水分调亏处理马铃薯全生育期总耗水量均低于全生育期充分灌水CK处理。块茎形成期轻度水分亏缺马铃薯水分利用效率、灌溉水利用效率、生物量均达到最大,较全生育期充分灌水显著提高29.04%,35.61%。因此,块茎形成期轻度水分亏缺灌溉方式能使马铃薯根区土壤始终保持湿润状态,有效减少渗漏损失和植株间无效蒸发损失,改善土壤水、肥和热量状况,有利于提高作物水分利用效率,且不显著降低马铃薯最终产量。  相似文献   

20.
为了探明不同调亏程度对海岛棉产量及品质的影响,通过田间小区试验,以正常灌水量为对照,设置轻度调亏（正常灌水量的75%）、中度调亏（正常灌水量的50%）和重度调亏（正常灌水量的25%）,研究调亏灌溉对海岛棉不同部位优质成铃特性的调节效应。结果表明：轻度调亏对棉花产量品质无显著影响,而中度和重度调亏使皮棉产量分别下降了10.8%和25.4%,主要是单株铃数和单铃重显著下降。轻度和中度调亏对衣分影响较小,但重度调亏使衣分显著下降。轻度和重度调亏使纤维长度略有下降,中度调亏则纤维长度增加。纤维比强度和马克隆值随调亏程度增加呈增大趋势,但差异不显著。从不同结铃部位分析,轻度调亏使棉花中部铃重、纤维长度、比强度增大,上部铃重、纤维长度显著降低。而中度和重度调亏均使中部铃重、衣分显著下降,中度调亏使中部棉铃纤维比强度增加,而重度调亏可显著提高下部棉铃纤维比强度。轻度调亏使中部、中度调亏使下部、重度调亏使上部棉铃纤维马克隆值显著增大。  相似文献   

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