灌溉制度对膜下滴灌甜菜产量及水分利用效率的影响

为制定新疆合理的甜菜膜下滴灌制度,设置3个灌水次数(8、9和10次)和2个灌水定额(45和60mm)两因素全组合试验,于2016—2017年在新疆玛纳斯县农科院甜菜改良中心开展田间试验。结果表明,灌水次数增加时甜菜叶面积指数与产量增加,含糖率降低,对甜菜的水分利用效率、耗水量无明显影响(P0.05),甜菜叶绿素值随灌水次数与定额增加呈下降趋势;在灌水次数与定额交互作用下,灌水8次时由于土壤相对含水率低于50%,甜菜会减产;当灌水9次,灌水定额为45 mm时,增加15 mm灌水定额土壤相对含水率达50%以上,此时甜菜增产7.4%～7.7%,糖产增加9.4%～9.7%;而继续增加灌水次数时,会导致甜菜含糖率降低而降低糖产。因此针对新疆膜下滴灌甜菜以60 mm灌水定额灌水9次为宜,可获得高产与糖产,较传统新疆膜下滴灌甜菜制度节水10%。该研究对指导新疆膜下滴灌甜菜灌溉制度具有一定意义。     

滴施改良剂对新疆盐碱土改良及甜菜产量的影响

为了明确滴施化学改良剂对新疆盐碱土盐碱指标的影响,合理选用化学改良剂,选择4种滴灌专用盐碱改良剂类产品(酸碱平衡护理剂、酸酸肥霸、肽能氮、生物有机菌肥),以不施化学改良剂为对照,对施用前后土壤盐分、pH值、钠吸附比、总碱度、碱化度指标变化和甜菜锤度、产量的差异进行分析。结果表明:与不施化学改良剂相比,酸碱平衡护理剂处理和生物有机菌肥处理使土壤pH值分别降低了0.67和1.03个单位,达到显著水平(P0.05)。除施用酸酸肥霸处理的土壤盐分上升外,其余3种改良剂处理的土壤盐分均下降,施用生物菌肥使土壤盐分下降1.19 g/kg,达到显著水平(P0.05)。施用改良剂使土壤CO_3~(2-)和HCO_3~-的降幅达2.00%~80.00%,酸碱平衡护理剂和肽能氮主要降低土壤中CO_3~(2-)的含量,分别降低了49.50%和30.00%;酸酸肥霸降低HCO_3~-的效应优于CO_3~(2-);生物菌肥对HCO_3~-和CO_3~(2-)均有显著的降低作用,分别下降了60.40%和80.00%。4种盐渍土改良剂均能够有效地降低土壤耕层总碱度和pH值,以生物有机菌肥效果最显著;肽能氮和生物有机菌肥可同时降低土壤钠吸附比和碱化度,显著提高了甜菜的产量,但酸酸肥霸和酸碱平衡护理剂处理的甜菜产量与对照相比差异不显著。     

Soil erosion from sugar beet in Central Europe in response to climate change induced seasonal precipitation variations

This study estimates the implications of projected seasonal variations in rainfall quantities caused by climate change for water erosion rates by means of a modeling case study on sugar beet cultivation in the Central European region of Upper-Austria. A modified version of the revised Morgan–Morgan–Finney erosion model was used to assess soil losses in one conventional and three conservation tillage systems. The model was employed to a climatic reference scenario (1960–89) and a climate change scenario (2070–99). Data on precipitation changes for the 2070–99 scenario were based on the IPCC SRES A2 emission scenario as simulated by the regional climate model HadRM3H. Weather data in daily time-steps, for both scenarios, were generated by the stochastic weather generator LARS WG 3.0. The HadRM3H climate change simulation did not show any significant differences in annual precipitation totals, but strong seasonal shifts of rainfall amounts between 10 and 14% were apparent. This intra-annual precipitation change resulted in a net-decrease of rainfall amounts in erosion sensitive months and an overall increase of rainfall in a period, in which the considered agricultural area proved to be less prone to erosion. The predicted annual average soil losses under climate change declined in all tillage systems by 11 to 24%, which is inside the margins of uncertainty typically attached to climate change impact studies. Annual soil erosion rates in the conventional tillage system exceeded 10 t ha^− 1 a^− 1 in both climate scenarios. Compared to these unsustainably high soil losses the conservation tillage systems show reduced soil erosion rates by between 49 and 87%. The study highlights the importance of seasonal changes in climatic parameters for the discussion about the impacts of global climate change on future soil erosion rates in Central Europe. The results also indicate the high potential of adaptive land-use management for climate change response strategies in the agricultural sector.     

甜菜谷氨酸合成酶活性与块根产量、含糖率的相关性分析

采用双丰16(偏丰产型)和甜单1号(偏高糖型)两个甜菜(Beta vulgaris L.)品种作为试材,在5个氮素水平(0、60、120、180和240 kg.hm-2)下,研究甜菜功能叶片与块根中谷氨酸合成酶(glutamate syn-thase,GOGAT)在生育进程中的活性变化动态及其与块根产量、含糖率和产糖量的关系。结果表明:在不同氮素水平下,两个品种功能叶片和块根的GOGAT活性均呈双峰曲线变化,两峰值分别出现在6月下旬和8月下旬,其中,功能叶GOGAT前一峰值高于后一峰值;块根GOGAT则与之相反。在不同氮素水平下,功能叶片GOGAT活性表现为N180>N120>N240>N60>N0,块根GOGAT表现为N120>N180>N240>N60>N0。GOGAT的活性与块根产量及含糖率关系紧密,块根产量随GOGAT活性的增加而提高,但是GOGAT活性过高反而降低了块根含糖率,进而导致甜菜产糖量的降低。     

Sugar beet yield response to different levels of saline irrigation water and leaching in an arid region

The main objective of this work was to evaluate the effects of saline irrigation water and leaching on the sugar beet yield components. In a field experiment in Rudasht region (Isfahan, Iran), three irrigation water salinity levels (1.6, 8.1, and 12.3 dS m^?1) and with/without leaching were applied. The experimental units comprised of a completely randomized block design, with split plot in four replications. The results indicated that the white sugar yield and alkalinity decreased by increasing the water salinity. Salts leaching significantly increased the root yield, white sugar yield, and white sugar concentration. With higher levels of water salinity molasses sugar, leaf weight, and the concentrations of Na, K, and α- amino-N in sugar beet significantly increased. Consequently, it appears that the use of drainage water in combination with fresh water could be recommended as a strategic management way to grow sugar beet in the investigated arid region.     

气候变化情景下新疆棉花和甜菜需水量的变化趋势

利用改进的非参数统计检验Mann-Kendall(MK)方法进行序列趋势检验时,因考虑了时间序列自相关性的影响而使检验结果更趋严格。本文采用MK法及改进的MK法对新疆地区41站1961-2010及2015-2099年主要经济作物棉花和甜菜需水量ETc和相关气候要素的变化趋势进行了检验,探讨了序列自相关性对ETc趋势检验结果的影响,并给出了各站及全疆ETc的变化趋势。结果表明:1)当自相关阶数大于0时,应采用改进MK法判断ETc的变化趋势;2)1961-2010棉花和甜菜的ETc具有一定的相依结构,2015-2099年棉花的ETc具有非常明显的长程相关性,但2015-2099年甜菜的ETc均具有时间独立性;3)无论对于棉花还是甜菜ETc,各站点Sen斜率和线性斜率值很接近,满足极好的线性关系,表明两者在反映趋势幅度时具有高度一致性;4)ETc序列是否存在相依性对于趋势显著性有重要影响,最终的趋势检验需用MK法和改进的MK法综合判断。1961-2010和2015-2099年棉花和甜菜的ETc在多数站点呈下降趋势,但其显著性各异。ETc序列的下降说明未来新疆棉花和甜菜用水需求降低,遭受干旱的风险降低。棉花及甜菜ETc的趋势特征对于气候变化背景下干旱-半干旱区作物灌溉制度的制定和防灾抗旱有重要参考价值。     

Effect of Zinc applied together with compound fertilizer on yield and quality of sugar beet (Beta vulgaris L.)

This research was conducted to evaluate the effect of zinc, added into compound fertilizer in the production process, and zinc applied together with compound fertilizer on yield and quality component of sugar beet in 2009–2010.The treatments consisted of nitrogen, phosphorus and potassium (NPK) (12-30-12) compound fertilizer; 2. NPK (12-30-12) compound fertilizer + zinc sulfate and NPK (10-20-20) + 1% Zn compound fertilizer. Root yield, sugar percentage, white sugar percentage (WSP), white sugar yield (WSY), alpha-amino nitrogen, sodium and potassium concentration were investigated in this study. A total of 5 kg ha^?1 zinc application on sugar beet significantly increased the yield and quality of sugar beet; the rate of increase was in the range of 4.62–6.97% in root yield, 2.09–5.75% in sugar percentage, 2.60–8.03% in WSP and 7.84–13.06% in WSY. NPK (10-20-20) + 1% Zn compound fertilizer and NPK (12-30-12) compound fertilizer + zinc applications increased the sugar beet yield and quality values in both years.     

Additions of ammonium sulfate and urease inhibitor with urea to improve spring wheat and sugar beet yield

Additions of ammonium sulfate and urease inhibitor with urea might have potential to increase yield and quality due to increased supply of sulfur (S) and reduction in volatilization loss of nitrogen (N), respectively. Treatments consisting, (i) urea alone, (ii) urea with ammonium sulfate (UAS) and (iii) homogeneous granular fertilizer containing urea and ammonium sulfate (HBU), and (iv) urease inhibitor treated urea (UI), at two application rates, 134 and 168 kg N ha^?1, were compared for spring wheat (Triticum aestivum L.) and sugar beet (Beta vulgaris L.) production at Glyndon and Ada of Minnesota, USA, during 2014–2015. For both crops, additions of UI had increased yield due to higher soil N availability over urea only in 2015. In 2014, UI also increased the grain protein content over urea and UAS increased sugar content only over HBU in 2015. Spring wheat and sugarbeet yield and quality response to urease inhibitor or supply of S in the form of UAS depends on soil and climatic factors.     

Nutrients management strategies to improve yield and quality of sugar beet in semi-arid regions

The objective of this study was to evaluate the effects of organic and inorganic fertilizers on the yield and quality of sugar beet genotypes (Beta vulgaris L.). Therefore, a field trial was carried out in Peshawar, Pakistan, during the winters in 2012–2013. The field experiment was conducted in a randomized complete block design with split plots, having three replications. Fertilizer treatments (control, composted manure Higo Organic Plus at 5 t ha^?1, Maxicrop Sea Gold seaweed extract at 5 L ha^?1, farm yard manure at 10 t ha^?1, inorganic nitrogen–phosphorus (NP) at 90:60 kg ha^?1, NP at 120:90 kg ha^?1 and NP at 150:120 kg ha^?1) were allotted to main plots, while genotypes (Sandrina, Serenada and Kawe Terma) were allotted to the sub-plots. Plots treated with the application of NP at 120:90 kg ha^?1 produced the highest beet yield (76.4 t ha^?1) and sugar yield (11.1 t ha^?1), and had the second highest polarizable sugar content (14.52%) and more economic return (Rs. 553,000 per hectare) as compared to control plots. Sugar beet genotype Serenada had significantly higher beet yield (55.5 t ha^?1) and sugar yield (7.9 t ha^?1) and a higher economic return (Rs. 380,000 per hectare) than the other genotypes. Sugar beet genotype Serenada supplied with NP at 120:90 kg ha^?1is recommended for the general cultivation in the agro-climatic conditions of Peshawar valley.     

气候变化下干旱对中国玉米产量的影响

了解干旱的时空变化特征及其对农业生产的影响对于维护农业可持续发展具有重要意义。该研究以中国五大主要玉米种植区中241个地级行政单元作为研究对象,采用AquaCrop作物模型分别对rcp2.6、rcp4.5、rcp8.5,3种代表性浓度路径情景中玉米在不同灌溉条件下的受到的水分胁迫及相应产量进行模拟,在此基础上通过建立回归模型评估干旱强度对玉米产量损失的影响。结果表明,1）未来中国的干旱强度分布及玉米产量损失在空间上均呈现由西北至东南递减的趋势;2）未来时期全国大部分地区干旱水平相比于历史时期有所上升;3）玉米干旱损失率随干旱指数的变化特征符合Logistic曲线,回归结果的R2为0.96。4）未来北方春播玉米区和黄淮海夏播玉米区的玉米产量对干旱强度反应最敏感,应当引起格外重视。     

The response of drought-tolerant sugar beet to salinity stress under field and controlled environmental conditions

Abstract

Thirty-four sugar beet drought-tolerant half-sib families were screened in greenhouse experiment under saline (16?dSm^?1) and normal conditions, and a subset of 10 tolerant genotypes were selected for evaluating of yield-related traits, Na⁺, K⁺, and α-amino-N nitrogen contents under saline field condition (12?dSm^?1). Drought-tolerant genotypes showed a different tolerance level under salt stress. Significant correlation was observed between EP2_s and STIEP2 in greenhouse with root yield (RY) in saline field condition. It should be possible that a simple measurement at 16?dSm^?1 in the greenhouse can be used as main part of sugar beet salt-tolerant breeding program. In total, genotypes SBSI-DR I-HSF14-P.23 (# 16) and 436B-HSF9-P.27 (# 26) were recognized as salt- and drought-tolerant genotypes with low Na⁺ and K⁺ contents in root and high white sugar content (WSC) and RY in field. A larger panel of genotypes to validate this kind of association is necessary.     

Effect of soil type on the time-course of changes in sugar beet (Beta vulgaris L.) productivity in Tokachi District,Hokkaido, Japan

Abstract

To clarify the effect of soil type on changes in sugar beet (Beta vulgaris L.) productivity since 1980 in Tokachi District (Hokkaido, Japan), we analyzed yield data from 121 settlements from 1980 to 2002 using maps of parent materials and surface organic matter contents in a geographical information system. The soil types were Brown Lowland soils, Andosols with an alluvial subsoil, Wet Andosols and Andosols. The sugar beet yields were highest in the Andosols and moderate in Andosols with an alluvial subsoil. Yields in Brown Lowland soils in the 1980s were similar to those in Andosols, but decreased below the yields in the Andosols by the 1990s. The yields in Wet Andosols were the lowest in the 1980s, but have been similar to those in Andosols with an alluvial subsoil since 1990. Thus, productivity appears to have varied over time in Brown Lowland soils and Wet Andosols. The correlation coefficients between yields and cumulative daily mean temperature from late April to mid-July since 1990 were highest in the Andosols (r = 0.67), lowest in the Brown Lowland soils (r = 0.50) and intermediate in the other soil types (r = 0.54–0.60). However, the magnitude of the correlation between the yield and the cumulative precipitation since 1990 was lowest in the Andosols (r = –0.22), highest in the Brown Lowland soils (r = –0.58) and intermediate in the other soil types (r = –0.44 to –0.45). These results suggest that the present soil water environment in the Andosols is superior to that in the other soil types.     

Abiotic soil properties and the occurrence of Rhizoctonia crown and root rot in sugar beet

Since 1993, Rhizoctonia crown and root rot (Rhizoctonia solani AG 2–2 IIIB) has represented an increasing problem for sugar beet production in Germany. Up to now, the outbreak of the infection and the spread of the disease within a field cannot be predicted and effective countermeasures are not available. Although little is known about the living conditions of R. solani in soils, abiotic soil properties are likely to influence the disease occurrence. Investigations were carried out based on 60 pairwise comparisons, each consisting of a disease‐affected and an adjacent nonaffected patch on farmers' fields in 2002 and 2003. Soil samples from the top soil layer (0–30 cm) were collected before harvest, and eight of the most frequently mentioned soil properties potentially influencing Rhizoctonia crown and root rot infection were examined: bulk density, texture, carbonate carbon, potassium, phosphorus, organic carbon, total nitrogen, and pH. The occurrence of the disease was significantly related to the soil C : N ratio, indicating the influence of soil organic matter on the disease occurrence. Examinations of soil thin sections showed that organic‐matter particles in the soil serve as a substrate for R. solani. All other soil physical and chemical properties examined did not differ between the disease‐affected and nonaffected patches and seem to be of minor importance.     

1961—2010年气候变化对西南冬小麦潜在和 雨养产量影响的模拟分析

利用农业气象试验站作物资料及土壤资料,评价 APSIM-Wheat 模型在西南地区的适应性,应用该模型分析该地区1961—2010年冬小麦潜在和雨养产量的时空变化特征,通过逐步回归分析揭示小麦生长季主要气象因子对潜在产量和雨养产量的影响及相对贡献率。研究结果表明： APSIM 模型对该区5个常用小麦品种的模拟效果较好,模拟与实测生育期的均方根误差(RMSE)在7.0 d 以内,地上部分生物量和产量模拟值与实测值的归一化均方根误差(NRMSE)均低于25%,模型在西南地区具有较好的适应性。1961—2010年研究区域36%的站点冬小麦生长季总辐射显著降低,其中北部、东南部和南部中区最显著;68%的站点生长季≥0℃有效积温显著增加,西部增温显著;30%的站点生长季平均气温日较差显著减小,南部中区最显著;全区生长季总降水大面积减少但不显著,减少区主要位于最南端和东南部。模拟的冬小麦潜在产量在65%的站点呈显著减产趋势,南部中区和北部变化最明显;雨养产量在25%的站点显著降低,北部地区较明显,全区减产趋势较弱。减产显著的站点中,生长季辐射降低、温度升高、气温日较差减小对潜在产量降低的贡献率分别为45%、36%和2%,对雨养产量降低的贡献率分别为36%、39%和－8%,而降水减少对雨养产量降低的贡献率为7%。西南冬小麦生长季辐射降低、温度升高及降水减少共同导致了冬小麦潜在和雨养产量的显著下降,而气温日较差的降低对冬小麦潜在和雨养产量的影响分别表现为负作用和正作用,整体上辐射和温度的影响程度最大。     

Yielding of sugar beet cultivated after manure and Vermicompost in the background of increasing doses of nitrogen fertilization

In the experiment, yield formation value of vermicompost and manure incorporated into soil were compared in cultivation of sugar beet. It was proved, that vermicompost (10 t/ha) could fully replace manure (30 t/ha) traditionally used for sugar beet. As a result even higher yield of roots, of leaves and biomass using compost were noticed. In case of nitrogen fertilization dose 140 kg/ha seems to be the most suitable.     

气候变化对关中地区粮食产量的影响及趋势分析

以增温为主的气候变化对粮食产量具有显著影响。本文利用关中地区1983—2016年的站点气象要素、粮食产量统计数据和跨部门影响模型比较计划(Intersectoral Impact Model Intercomparison Project, ISIMIP)中4个全球气候模式2021—2050年降水、气温输出结果,采用突变分析、趋势分析和敏感性分析等方法,从粮食单产、气候产量和气候生产潜力等方面系统分析了我国主要粮食产地之一的陕西关中粮食产量对气候变化的响应特征。结果表明:1)1983—2016年,关中地区年平均气温呈显著上升趋势,升温速率为0.05℃·a~(-1)(P0.01),其中,最高气温的上升起主要作用;年降水量则以~(-1) mm·a~(-1)的速率呈下降趋势,但不显著。2)关中地区多年平均粮食单产为3 599 kg·hm~(-2),且逐年波动上升,速率为57.17kg·hm~(-2)·a~(-1)(P0.001)。关中多地的气候产量与气温呈正相关,气温的升高一定程度上促进了关中气候产量的增加,但并不显著(平均增加率为0.85 kg·hm~(-2)·a~(-1))。渭河关中地区多年以来的气候生产潜力为7 000～12 000kg·hm~(-2),受气温波动的影响,1995年后的平均气候生产潜力高于1995年之前,是整个研究时段气候生产潜力呈现增加趋势的主要时期。3)未来30年里(2021—2050年),关中地区在RCP2.6情景下的平均气候生产潜力略高于RCP6.0情景,但前者的生产潜力呈逐年下降趋势,后者则表现出逐年上升趋势。关中地区的作物对气候资源的利用空间还很大,且气候变化对关中粮食产量具有促进作用,但此正向作用并不是持续不变的。     

Modelling the effect of environmental change on shorebirds: A case study on Poole Harbour, UK

An individuals-based model, MORPH, was used to assess the quality of Poole Harbour, UK, for five overwintering shorebirds: dunlin Calidris alpina, redshank Tringa totanus, black-tailed godwit Limosa limosa, oystercatcher Haematopus ostralegus and curlew Numenius arquata. Site quality, and the effect of environmental change, was measured as predicted overwinter survival. Dunlin had the highest prey biomass densities and were the least likely to be affected by reductions in their food supply, lower temperatures or loss of terrestrial habitats. Black-tailed godwits and curlew had the lowest prey biomass densities and were the most likely to be affected by reductions in their food supply, lower temperatures and loss of terrestrial habitats. All five shorebird species were seriously affected by simulated sea-level rise. Conservation issues identified for the Poole Harbour SPA were the relatively low densities of larger size classes of polychaete worms, the importance of maintaining and managing surrounding terrestrial habitats and the effect of sea-level rise on the length of time for which intertidal food supplies are available.     

农业技术和气候变化对农作物产量和蒸散量的影响

随着农业生产条件的改善、品种改进和有利的气象条件的变化, 世界各地的作物产量得到大幅度提高, 但作物的蒸散量却未出现大幅度提高。本文以石家庄气象站1955~2007 年的气象资料为基础, 分析了河北省冬小麦和夏玉米生长期间主要气象因素变化, 结合中国科学院栾城农业生态系统试验站长期定位灌溉试验的研究结果, 分析了农业生产条件和气象因子变化对冬小麦和夏玉米产量及耗水量的影响。结果表明,1955~2007 年冬小麦和夏玉米生长季的气象因子发生了变化, 日照时数、相对湿度、风速、气温日较差显著降低, 最低气温、平均气温和积温显著升高, 气象因子的变化对作物总蒸散量未产生明显影响, 但由于降水减少,作物生长期间的灌溉需水量呈增加趋势。长期灌溉试验结果表明, 随着农业生产条件的变化和品种的改良, 冬小麦和夏玉米的产量不断增加, 而耗水量的增加幅度小于产量增加幅度, 夏玉米的耗水量呈稳定状态。节水技术的推广和应用对维持耗水量稳定起着非常关键的作用。     

Sugar beet (Beta vulgaris L.) response to diammonium phosphate and potassium sulphate under saline–sodic conditions

Salinity and sodicity are prime threats to land resources resulting in huge economic and associated social consequences in several countries. Nutrient deficiencies reduce crop productivity in salt‐affected regions. Soil fertility has not been sustainably managed in salt‐affected arid regions. Few researchers investigated the crop responses to phosphorus and potassium interactions especially in saline–sodic soils. A research study was carried out to explore the effect of diammonium phosphorus (DAP) and potassium sulphate (K₂SO₄) on sugar beet (Beta vulgaris L.) grown in a saline–sodic field located in Kohat district of Pakistan. The crop was irrigated with ground water with EC_iw value of 2.17–3.0 dS/m. Three levels each of K₂O (0, 75 and 150 kg/ha) as K₂SO₄ and P₂O₅ (0, 60 and 120 kg/ha) as DAP were applied. The application of P significantly affected fresh beet and shoot yield while K fertilizers had significant effect on fresh beet yield and ratio of beet:shoot, while non‐significant effects on the fresh shoot were observed. The application of K₁ and K₂ promoted sugar beet shoot yield by 49.2 and 49.2% at P₁ and 64.4 and 59.7% at P₂, respectively over controls. In comparison with controls, fresh beet yield was increased (%) by 15 and 51, 45 and 84, and 50 and 58 for corresponding K₁ and K₂ at P₀, P₁ and P₂, respectively. Addition of P₁ and P₂ increased beet yield by 37 and 47% over control. The shoot [P] (mmol/kg) were achieved as 55.2, 73.6 and 84.3 at P₀, P₁ and P₂, respectively. The shoot [Mg] and [SO₄] tended to decrease with increasing P levels, while [SO₄] was markedly reduced at P₂. The effect of P on leaf [Na] was non‐significant, but increasing levels of K decreased [Na] substantially at P₀ and P₁, but there was no difference in the effect of K level on [Na] at P₂. Consequently, K application reduced leaf Na:K ratios. Fresh shoot yield was weakly associated with leaf [P] (R² = 0.53). The leaf Na:K ratio showed a negative relationship (R² = 0.90) with leaf [K]. A strongly positive relationship (R² = 0.75) was observed between leaf [K] and fresh beet yield. The addition of K₂SO₄ also enhanced [SO₄] and SO₄:P ratios in leaf tissues. The ratio of Na:K in the shoot decreased with increasing K application. These results demonstrated that interactions of K and P could mitigate the adverse effects of salinity and sodicity in soils. This would contribute to the efficient management of soil fertility system in arid‐climate agriculture.     

不同浓度钠对甜菜生长及生理特性的影响

采用1/2 Hoagland 营养液室内培养试验,研究不同浓度Na+ 对甜菜幼苗生理生化指标和营养元素吸收的影响。结果表明,0.759 mmol/L Na+可提高甜菜幼苗体内Na+ 含量和幼苗高度,增加叶面积（除了9 mmol/L Na+）和干物质量,降低叶片水势,提高叶片的相对含水量、 GPX和CAT的活性,促进甜菜幼苗叶片的吸水及保水能力。3 mmol/L Na+对甜菜幼苗的生长促进作用最明显,可提高CAT、 GPX活性并维持较高的SOD活性,降低MDA含量和相对电导率,未明显降低甜菜体内N、 P和K含量,是甜菜幼苗生长的最佳Na+浓度。