Screening Soybean Cultivars for Resistance to Iron-Deficiency Chlorosis in Culture Solutions Containing Magnesium or Sodium Bicarbonate

ABSTRACT

Hydroponic culture solutions containing bicarbonate (HCO₃ ^?) may be used to screen crops such as soybeans (Glycine max) for resistance to iron (Fe) deficiency or chlorosis. Some successful methods use sodium bicarbonate (NaHCO₃) in combination with elevated partial pressures of carbon dioxide (CO₂) to buffer pH and elevate bicarbonate. Replacing NaHCO₃ with magnesium bicarbonate [Mg(HCO₃)₂] as the form of bicarbonate alkalinity has the potential to produce culture solutions that simulate soil solutions more closely and eliminate any potential for specific sodium (Na) toxicities in sensitive plants. A modified screening solution based on Mg(HCO₃)₂-CO₂ was tested against the successful NaHCO₃-CO₂ method, using three soybean varieties of known resistance to Fe-deficiency chlorosis. Alkalinity was 10 mM [added as NaHCO₃ or Mg(HCO₃)₂], solutions were aerated with 3% CO₂, and Fe was provided as FeDTPA (diethylenetriamine-pentaacetic acid) at 15 μM (low Fe) or 60 μM (adequate Fe). Leaf chlorophyll, visual chlorosis index, and leaf Fe concentration were closely related. Solutions based on NaHCO₃ or Mg(HCO₃)₂ provided identical chlorosis-susceptibility rankings for the three cultivars.     

Arbuscular Mycorrhizal Fungi Enhance Tolerance of Rosa multiflora cv. Burr to Bicarbonate in Irrigation Water

ABSTRACT

High bicarbonate (HCO₃ ^?) of irrigation water can be detrimental to plant growth in sustainable horticultural production systems. The ability of arbuscular mycorrhizal fungi (AMF), ZAC-19, (composed of Glomus albidum, Glomus claroideum, and Glomus diaphanum) to enhance tolerance to HCO₃ ^? was tested on Rosa multiflora cv. Burr. Arbuscular mycorrhizal colonized and non-inoculated (non-AMF) plants were treated with 0, 2.5, 5, and 10 mM HCO₃ ^?. Increasing HCO₃ ^? concentration and associated high pH and electrical conductivity (EC)—reduced plant growth, nutrient uptake, and acid phosphatase activity, while increasing alkaline phosphatase activity (ALP). Inoculation with AMF enhanced plant tolerance to HCO₃ ^?, as indicated by greater growth (leaf, stem, and total plant dry weight, leaf area and leaf area ratio), leaf elemental concentration [nitrogen (N), phosphorus (P), potassium (K), calcium (Ca), iron (Fe), zinc (Zn), aluminum (Al), boron (B)], leaf chlorophyll concentration, higher mycorrhizal inoculation effect, lower root Fe reductase activity, and generally lower soluble ALP activity. While AMF colonization was reduced by increasing HCO₃ ^? concentration, colonization still occurred at high HCO₃ ^? concentration. At 2.5 mM HCO₃ ^?, AMF plant growth was comparable to plants at 0 mM HCO₃ ^?, further indicating the beneficial effect of AMF for alleviation of HCO₃ ^? plant stress.     

不同改良剂对旱地苹果园壤土团聚体和水分的影响

为对比研究植物根际促生菌(枯草芽孢杆菌、胶质芽孢杆菌)和苹果树枝生物炭的施加对黄土丘陵区山地苹果园粉质壤土团聚体含量、稳定性以及土壤水分的影响,采用田间定位试验,设置4个处理:施加65 t/hm2生物炭(BC)、20 t/hm2枯草芽孢杆菌(PGBS)、20 t/hm2胶质芽孢杆菌(PGBM)和对照(CK).湿筛法获得...     

充分灌与调亏灌溉条件下苹果树微喷灌的耗水量研究

田间试验设置有两个处理：整个生育期以蒸发量的80％灌溉的充分灌处理；6月中旬到7月中旬以蒸发量的40％灌溉，而其它季节恢复以蒸发量的80％灌溉的调亏灌溉处理（RDI）。 试验得出了苹果树微喷灌在上述两种灌溉条件下不同生育期的日均耗水量与蒸发皿系数。与充分灌比较，调亏灌溉处理的产量基本上没有受到影响，而灌水量减少了17%～20％，耗水量减少了10.2%～11.2%，并有效地抑制了枝条生长。     

渭北旱塬红富士苹果需水量与限水灌溉效应研究

应用田测法,对渭北旱塬南部高原台塬过渡区,矮化红富士苹果需水量、需水规律及限水灌溉效应进行了研究。结果表明,该区矮化红富士苹果生育期总需水量为494.8～552.7 mm,其中干旱年份高于湿润年份;年生育期内以6月最大,7～8月次之,10月最小。果实膨大和花芽分化盛期需水量最大,占总需水量的41.4%～46.7%,新梢生长与果实发育前期次之,占总需水量的34.0%～34.2%;并得出了该区矮化红富士苹果生育期的作物系数KC值。对不同降水年型土壤水分盈亏状况与该区降水特点分析表明,该区50%年份降水能够满足     

Influence of Rootstocks,pH, Iron Supply (in Nutrient Solutions) and Agrobacterium radiobacter on Chlorophyll and Iron Concentration in Leaves of a Peach Variety

In this study, the influence of rootstocks, pH, iron (Fe) supply (in nutrient solutions), and Agrobacterium radiobacter on the leaf chlorophyll and Fe concentration of the peach cultivar ‘Sun Crest’ was investigated. The results showed that chlorophyll index (SPAD-502) and active Fe differed significantly at different pH levels. Chlorophyll index was highest at pH 6.0 and 9.0 and lowest at pH 7.0 and 8.0 Leaf active Fe concentration was highest at pH 6.0 and 7.0 Significant differences between rootstocks and interactions were also found. Chlorophyll index was highest in the leaves of GF677, Antafuel and MRS 2/5, while the leaves of seedling had the lowest chlorophyll index and chlorophyll a and b concentration. The chlorophyll index in the leaves of St. Julien 655/2 did not differ from those of MRS 2/5. However, seedling had the highest leaf active Fe concentration. Supply of trees with different Fe levels (in solutions) did not affect positively the leaf chlorophyll index, chlorophyll a and b concentration, or active Fe concentration. The leaf chlorophyll index and active Fe in the rootstocks GF677, Antafuel, and Siberian C were significantly reduced in trees inoculated with Agrobacterium radiobacter.     

天然油菜素内酯对黄土丘陵区苹果生长发育和产量的影响

在黄土丘陵区坡地台田水肥亏缺的条件下,用4种不同浓度的天然油菜素内酯(NBR)在展叶期喷施于富士苹果叶面。试验结果表明,天然油菜素内酯处理增加了叶片相对含水量和临界饱和亏,降低了自然饱和亏、需水程度、蒸腾强度、细胞膜透性和伤害率。在不同浓度的处理中,0.30mg/L的处理效果最好,与对照相比,天然油菜素内酯处理使苹果叶片相对含水量和临界饱和亏提高了11.8%和59.7%,自然饱和亏和需水程度分别降低了42.6%和52%,蒸腾强度(12:00～14:00)降低了30%左右,细胞膜透性和伤害率各降低了9.4%和37.5%。天然油菜素内酯处理减少了叶片的水分损失,提高了苹果的抗旱性。生长末期调查发现,天然油菜素内酯处理增加了苹果叶片的长度、宽度和厚度,抑制了秋梢的萌生和生长,座果率从43.4%提高到63.3%,单株产量比对照增加了8.1%～16.8%,其中0.3mg/L的处理增产效果最为明显。     

水氮耦合对苹果光合特性和果实品质的影响

通过不同灌水量和施氮处理,研究水氮耦合对红富士苹果光合特性及品质的影响。结果表明:红富士苹果的光合特性在不同水肥组合下的变化不同,其光合作用存在明显的“午休”现象。中水高肥和高水高肥的肥水组合对光合速率的保持有一定的作用。低水中肥的肥水组合的蒸腾速率最低,保水效果最好。中度水分供应条件下,施用较多的氮肥可以提高气孔导度利于光合的进行。肥水管理以灌溉量5250m³/hm²、氮肥施用量600kg/hm²方案能获得较高的品质效益。     

水氮耦合对南疆地区红富士苹果矿质元素含量的影响

新疆自治区南部阿克苏地区是新疆红富士苹果的主要产区。以该区红富士苹果为对象,设置不同水氮处理,利用原子吸收法测定了果实中6种矿质元素的含量,分析了不同施肥、灌溉水平对各矿质元素含量的影响。结果表明,灌水适中条件下增施氮肥量可以提高苹果果实中Ca,Mg,Zn的含量;适度的灌水量和氮肥供应能维持Fe元素含量保持较高的水平,灌水量和氮肥供应过高、过低均不利于苹果果实中矿质Fe的积累。Cu和Mn含量与氮肥施用量呈正相关关系。     

The effect of potassium fertilization on iron deficiency

Abstract

Preliminary experiments indicate that potassium fertilization at a rate of 270 mg K/kg soil amel.iorates Iron deficiencies in peanuts grown in an extremely calcareous soil (63% CaCO₃). Amelioration was greater with the application of KCl than with that of KNO₃ or K₂HPO₄, indicating that the cation:anion balance of roct uptake is involved. Potassium chloride application caused a 73% increase in the chlorophyll content; this value is 90% of that of the FeEDDHA treatment. Manipulation of the cation: anion balance of macronutrients may prove to be an effective means of controlling lime‐induced chlorosis.     

灌溉水质对苜蓿早期生长及养分吸收的影响

采用盆栽试验方法,设计7种不同灌溉水质对苜蓿（Medicago sativaL.cv‘.Algonquin＇）进行灌溉处理,包括：清水灌溉（F）、再生水灌溉（R）、等营养水灌溉（E）、清水和再生水交替灌溉（T）、再生水和清水1∶1混合灌溉（FR）、再生水和清水1∶2混合灌溉（F2R）、再生水和清水2∶1混合灌溉（2FR）。研究结果表明,与清水灌溉（F）相比,再生水灌溉（R）可以明显提高苜蓿的株高和侧枝数水平;交替灌溉（T）和混合灌溉（2FR）对提高苜蓿干草产量作用明显;各灌溉水质对苜蓿叶茎比、根冠比和根系活力的影响都是暂时性的,长期进行灌溉影响不显著;混合灌溉（FR、F2R、2FR）和再生水灌溉（R）会提高苜蓿体内氮、钙和镁的含量,而对钾的含量没有影响,苜蓿体内磷的含量随各灌溉水质中磷含量的增加而减小。     

Effects of alumumium on nutrient composition and yield of oats

Spotty chlorosis appeared on the young leaves of Al toxic plants and was severe or high Al level. Stems of the Al‐treated plants were purple While the roots were short, thick and brown in colour with little branching.

The dry matter yield of tops and roots decreased with increased Al level. The concentration of P was greater in roots of Al toxic plants than in the control plants but a converse affect was recorded in tops.

Increased rates of Al caused a decrease in the concentrations of P,K,Ca, M_c and Mn in plant tops, while Al concentration increased both in tops and roots. Iron content in tops affected with increased Al and in root a regular increase was observed. The results indicate that Al toxicity depressed the growth of oats, resulted in abnormal root development with tittle branching and affecting the utilization of several essential plant nutrients by oat plant.     

铁肥虹吸输液对缺铁失绿苹果叶片光合生理指标和荧光参数的影响

为了进一步探索矫正苹果缺铁失绿症途径,采用铁肥虹吸输液方法,研究了铁肥虹吸输液对缺铁黄化叶片复绿,叶片解剖结构、 色素含量、 光合生理指标和叶绿素荧光参数的影响。结果表明,虹吸输液处理的复绿苹果叶片单个细胞叶绿体数目比对照增加了3.6个,淀粉粒有所减少;叶绿体内基粒结构更清晰、 垛叠增多;线粒体内嵴数量增多、 清晰度提高;叶绿体和线粒体的被膜结构得到修复。虹吸输铁后失绿程度由2.00级恢复到0.49级;铁肥虹吸输液显著提高了叶片的光合速率、 气孔导度,降低了细胞间隙的CO2浓度。输铁处理其PSⅡ原初光能转化效率（Fv/Fm）和PSⅡ潜在活性（Fv/Fo）均为最高。缺铁失绿苹果叶片叶绿素a、 叶绿素b含量分别比未输液对照增加2.97倍和3.18 倍。说明采取铁肥虹吸输液的方法能够矫正苹果缺铁失绿症。     

地表起垄微聚流技术对渭北果园土壤水分分布的影响

以渭北果园盛果期果树为研究对象,对地表起垄微聚流技术调控下0-600 cm土壤剖面水分含量在时间和空间上的分布状况进行了研究.结果显示;(1)在地表起垄微聚流处理下,年平均储水量为1 537.9 mm,高于对照9.99％,年周期内呈现双峰曲线变化趋势,分别在9月(1 616.2 mm)和2月(1 665.2 mm)达到高峰.(2)该技术能提高土壤剖面的土壤含水量.随土层深度的增加,土壤剖面水分空间分布呈现出减小—增大—减小的波浪型变化趋势.保水作用由强转弱后逐渐增强,可有效缓解果园深层土壤干燥化,有利于果园生态系统的健康稳定发展.(3)该技术能提高土壤水分利用效率,增加果树产量,改善果实品质.研究表明,地表起垄微聚流技术能有效利用膜垄的集水和沟覆盖的蓄水保墒功能,显著提高降水的利用效率,改善果树的水分状况,维持果园生态系统的稳定性.     

钠盐胁迫对苹果树体内钠累积的影响

钠盐胁迫严重制约着甘肃中东部地区苹果的生产。本研究以甘肃省秦安县大田生长的‘金冠’苹果为试材,用正常果树和盐碱胁迫果树对比方法,研究了自然条件下钠盐胁迫对果树整个生育期体内各器官（根系、枝条、叶片、花、果实）钠含量的影响。结果表明：钠盐胁迫下,果树根系内Na+含量为1800mg/kg,是正常果树的2倍;苹果花内Na+含量为700mg/kg,是正常果树的1.4倍;在整个生育期,果树枝条内Na+含量变化在800~1400mg/kg,大约是正常果树的2~4倍;叶片内钠含量变化在1700~2500mg/kg之间,是正常果树的3.4~8.5倍;果实钠含量在1200~1500 mg/kg之间,是正常果树的2.1~12倍。本研究科学地提出苹果花期属于钠盐潜在胁迫期。     

磁化水对盐胁迫下黄瓜生长和生理特性的影响

为探究磁化水浇灌对盐胁迫下黄瓜幼苗生长和生理特性的影响,采用人工气候室内进行的二因素二水平砂培试验,即2个磁化水水平(D:蒸馏水、M:磁化蒸馏水)和2个盐处理水平(Na0:0 mmol/L,Na1:100 mmol/L NaCl),共4个处理,研究了盐胁迫下磁化水浇灌对黄瓜幼苗生长、水分关系、光合气体交换、抗氧化能力、养分(N,P和K)及Na含量等的影响。结果表明:(1)无论在非盐胁迫和盐胁迫下,浇灌磁化水均具有改善黄瓜幼苗生长及/或生理活动的作用。磁化水在盐胁迫下改善黄瓜生长和生理活动的作用大于非盐胁迫下,且随盐胁迫或磁化水处理时间的延长,磁化水的效应增加。(2)盐胁迫下,磁化水浇灌改善黄瓜幼苗生长的主要生理机制在于:增加了黄瓜幼苗根系生长,改善了叶片水分关系,增加了叶片叶绿素含量、光合速率和水分利用效率,增强了叶保护酶活性从而降低了叶细胞膜受伤害程度,降低了根、茎和叶中的Na含量从而增加K⁺/Na⁺比。研究结果为磁化水用于次生盐渍化土壤上生长的黄瓜灌溉提供了理论依据。     

不同灌水技术下水氮耦合对山地苹果产量和品质及水氮利用的影响

为探究不同灌水技术下水氮耦合对山地苹果产量、品质及水氮利用的影响,采用三因素三水平正交试验,共设3种灌水技术(涌泉根灌(S)、陶瓷渗灌(P)和地表滴灌(D))、3个灌水量(高水(H₁)、中水(H₂)和低水(H₃))、3个施氮量(高氮(N₁)、中氮(N₂)和低氮(N₃)),共9处理,每个处理重复3次。分析山地苹果产量及水氮利用效率对不同灌水技术下水氮调控的响应规律。结果表明：灌水技术对单果重、维生素C和果实色泽有显著影响(p<0.05),灌水量和施氮量对苹果的产量、单果重、硬度、色泽、可溶性固形物、可滴定酸、可溶性糖、维生素C、糖酸比、氮肥偏生产力和灌溉水利用效率影响显著(p<0.05)。T₂处理(SH₂N₂)山地苹果产量(30 490.02 kg/hm²)最大,T₅处理(PH₂N₃)氮肥偏生产...     

Effects of Nitrate:Ammonium Ratios on Vegetative Growth and Mineral Element Composition in Leaves of Apple

Evaluations of vegetative growth and leaf concentrations of nitrogen (N), potassium (K), calcium (Ca), magnesium (Mg), and iron (Fe) were made of apple (Malus domestica Borkh. cvs. Granny Smith, Gala, and Golab) grown with five treatments of NO₃^?:NH₄⁺ ratios in pot culture. The concentrations of NO₃^?:NH₄⁺ ratios were 2.5:0.1, 6:0.3, 6:0.5, 6:0.7, and 6: 1 meq L^?1. Regression analysis showed that growth parameters of main stems and branches were not affected by increases of NH₄⁺ in the ratios. Granny Smith, Gala, and Golab differed in some of these parameters. Concentrations of N and Fe increased as NH₄⁺ increased, whereas K and Ca decreased and Mg was not affected significantly. Generally, the treatment of 2.5:0.1 produced leaves with lower N but higher K, Ca, and Mg concentrations than the other treatments. This research showed that vegetative growth was not affected by NH₄⁺ concentration whereas elemental composition was affected.     

土壤农艺调控措施对苹果和果园土壤镉污染的影响

以10a生红富士苹果树为试材,通过土施不同剂量的氯化镉和改良剂,研究了增施有机肥、磷钾肥以及土施生石灰等土壤农艺调控措施对苹果园镉污染的影响。结果表明:各处理的土壤有效镉含量、苹果叶片和果实镉含量均极显著低于对照。在本试验所设9个处理中,不同镉剂量处理下,以200g/kg有机肥+30g/kg生石灰+0.5g/kg磷钾肥处理和100g/kg有机肥+30g/kg生石灰+1g/kg磷钾肥处理的镉含量为低,使低、中、高3个镉剂量区土壤有效镉含量分别比对照减少36.6%,31.5%,22.9%;土壤有效镉含量比例分别比对照降低24.8%,21.4%,21.4%;叶片镉含量分别比对照减少41.6%,34.7%,17.0%;果实镉含量分别比对照减少53.9%,31.0%,28.6%。根据拟合公式推算出:当土壤镉含量低于2.95mg/kg时,200g/kg有机肥+30g/kg生石灰+0.5g/kg磷钾肥处理的果实镉含量较低;高于2.95mg/kg时,100g/kg有机肥+30g/kg生石灰+1g/kg磷钾肥处理的果实镉含量较低;两处理土壤镉调控极限值分别为7.84mg/kg和11.59mg/kg。在实验浓度范围内,土壤有效镉含量以及对苹果叶片、果实镉含量的直接通径系数和极差分析值均以生石灰为最高,有机肥次之,磷钾肥最低。生石灰对土壤有效镉含量以及对苹果叶片、果实镉含量的调控作用最强,有机肥次之,磷钾肥最小。     

根系分区交替灌水对玉米吸收养分影响的初步研究

通过盆栽试验研究了交替灌水方式、固定灌水方式和常规灌水方式对玉米吸收养分的影响。结果表明,拔节前期交替方式N吸收总量比固定方式高,和常规灌水方式相差不大,而后期则比固定、常规方式高;交替方式磷吸收总量均比其它两种方式高。交替方式氮、磷利用效率比常规方式分别提高25.1%,25.3%。交替方式比常规方式节约灌水量10.3%,其水分利用效率最高,比常规方式增加20.1%。