Stress Tolerance Parameters in Different Genotypes of Soybean

Free proline content, superoxide-dismutase activity, and lipid peroxidation were measured in sixteen Yugoslav and introduced genotypes of soybean. More tolerant genotypes with higher free proline content and high superoxide-dismutase activity, and low lipid peroxidation were chosen. The selected genotypes could be used in field production, as well as in breeding.     

Changes in the Metabolome of Two Soybean Genotypes under Drought Stress

Russian Journal of Plant Physiology - Soybean is the world’s leading economic oilseed crop. Drought stress is a major constraint on the growth and yield stability of soybean. Here, wild...     

干旱胁迫下大豆与玉米叶片光破坏的防御

随干旱强度的增加,大豆叶片光呼吸速率（Pr）降低的幅度小于Pn,使Pr／Pn比率升高。在轻度及中度干旱下,PSII光化学效率（Fv／Fm）能在暗置后较快地恢复。随干旱强度的增加,叶片光化学猝灭系数下降,非光化学猝死系数升高。干旱使叶片β－胡萝卜素及紫黄质含量下降,而玉米黄质含量（Z）与叶黄素库增加。与大豆相比,玉米在干旱条件下具有较高的Z含量和较大的叶黄素库。     

不同花生品种响应干旱胁迫后叶片内ABA与AhNCED1的分布

以粤油7号和汕优523两个不同抗旱性品种为材料,研究响应干旱胁迫后叶片ABA(abscisic acid,脱落酸)和AhNCED1(Arachis hypogaea nine-cis-epoxycarotenoid dioxygenase)的分布以及含量变化。结果表明,两种花生品种响应干旱胁迫后叶片的维管组织中ABA分布增强且含量增加,AhNCED1蛋白分布也增强;且在水分胁迫初期粤油7号花生AhNCED1蛋白分布强于汕优523,其体内ABA分布水平也高于汕优523;经ABA生物合成抑制剂Naproxen处理后,两种花生叶片ABA分布减弱,但粤油7号叶片维管组织中ABA分布水平仍高于汕优523。结果表明维管组织是干旱胁迫下花生叶片中ABA和AhNCED1分布的主要区域,且粤油7号花生抗旱性强可能与其体内AhNCED1和ABA的分布量较高有关。     

不同花生品种响应干旱胁迫后叶片内ABA与AhNCEDl的分布

以粤油7号和汕优523两个不同抗旱性品种为材料,研究响应干旱胁迫后叶片ABA（abscisicacid,脱落酸）和AhNCEDl（Arachishypogaeanine-cis-epoxycarotenoiddioxygenase）的分布以及含量变化。结果表明,两种花生品种响应干旱胁迫后叶片的维管组织中ABA分布增强且含量增加,AhNCEDl蛋白分布也增强;且在水分胁迫初期粤油7号花生AhNCEDl蛋白分布强于汕优523,其体内ABA分布水平也高于汕优523;经ABA生物合成抑制剂N印roxen处理后,两种花生叶片ABA分布减弱,但粤油7号叶片维管组织ABA分布水平仍高于汕优523。结果表明维管组织是干旱胁迫下花生叶片中ABA和AhNCEDl分布的主要区域,且粤油7号花生抗旱性强可能与其体内AhNCEDl和ABA的分布量较高有关。     

干旱胁迫对不同烤烟品种根系生长和生理特性的影响

以抗旱型烤烟品种‘农大202'及一般型烤烟品种‘NC89'和‘K326'为材料,采用盆栽试验研究了干旱胁迫对根系生长和生理特性的影响,以明确各烟草品种的抗旱能力及其与根系生长和生理特性的关系.结果显示:严重干旱胁迫之后各烤烟品种根系鲜重、干重上升,而根系活力、根系吸收面积以及根系SOD和POD活性等根系生理指标则呈下降趋势.在干旱胁迫条件下,‘农大202'的根系总吸收面积、活跃吸收面积、根系活力、SOD活性和POD活性均显著高于两对照品种‘NC89'和‘K326',但其根系鲜重和干重等生物量并不具有太大的优势.研究表明,烟草的根系生长和生理特性对环境水分条件的响应存在明显的基因型差异;在干旱胁迫条件下, ‘农大202'根系能保持较高总吸收面积、活跃吸收面积、根系活力和保护酶活性,是其具有较强抗旱性的生理基础.     

干旱胁迫及复水对不同黍稷品种根系生理特性的影响

以2种抗旱性不同的黍稷品种(‘陇糜4号’和‘晋黍7号’)为试验材料,采用盆栽试验研究了苗期中度和重度干旱胁迫后拔节期复水对其根系生理特性的影响。结果显示:(1)干旱胁迫引起2个黍稷品种根系活力明显下降,根系SOD、POD活性以及MDA、脯氨酸含量明显升高,而且重度干旱胁迫处理变化幅度显著大于中度干旱胁迫。(2)复水后,2个黍稷品种根系的各项生理指标均有不同程度的恢复,且中度胁迫处理较易恢复,重度胁迫下恢复能力很弱。(3)2个黍稷品种根系各项生理指标在干旱胁迫及复水条件下变化幅度不同,干旱胁迫下抗旱性强的‘陇糜4号’根系活力下降幅度明显低于抗旱性弱的‘晋黍7号’,根系SOD活性、POD活性、MDA含量和脯氨酸含量的上升幅度明显高于‘晋黍7号’,而复水后‘陇糜4号’根系的各项生理指标的恢复能力明显强于‘晋黍7号’。研究表明,干旱胁迫及复水条件下‘陇糜4号’均表现出较高的根系活力、保护酶活性和脯氨酸含量,且MDA含量较低,从而表现出较强的抗旱性。     

不同光合特性大豆叶的比例解剖研究

本研究选取不同光合速率的品种‘黑农26'(高产低光效)、‘黑农40'、‘黑农41'(高产高光效)为材料,于大豆开花后的不同生育时期,对大豆的功能叶片、叶柄解剖学进行了研究.结果表明(1)不同类型大豆的叶肉结构有明显区别.叶片厚度依次为‘黑农40'>‘黑农41'>‘黑农26'.各期的基本趋势是一致的.栅栏组织的厚度和层数与叶片的厚度趋势一致.(2)各品种栅栏组织中的叶绿体数目均多于海绵组织,且高光效类型多于低光效类型.局部观察不同品种间,叶绿体内的基粒和间质片层结构高光效的也明显优于低光效的品种.(3)气孔包含数量和大小两个因素,气孔大小基本一致,下表皮数量>上表皮,高光效类型>低光效类型.(4)各品种主脉维管束中木质部的导管数目依次为‘黑农41'>‘黑农40'>‘黑农26'.     

不同光合特性大豆叶的比较解剖研究

本研究选取不同光合速率的品种‘黑农 2 6’(高产低光效 )、‘黑农 40’、‘黑农 41’(高产高光效 )为材料 ,于大豆开花后的不同生育时期 ,对大豆的功能叶片、叶柄解剖学进行了研究。结果表明 :(1 )不同类型大豆的叶肉结构有明显区别。叶片厚度依次为‘黑农 40’ >‘黑农 41’ >‘黑农 2 6’。各期的基本趋势是一致的。栅栏组织的厚度和层数与叶片的厚度趋势一致。 (2 )各品种栅栏组织中的叶绿体数目均多于海绵组织 ,且高光效类型多于低光效类型。局部观察不同品种间 ,叶绿体内的基粒和间质片层结构高光效的也明显优于低光效的品种。 (3 )气孔包含数量和大小两个因素 ,气孔大小基本一致 ,下表皮数量 >上表皮 ,高光效类型 >低光效类型。 (4)各品种主脉维管束中木质部的导管数目依次为‘黑农 41’ >‘黑农 40’ >‘黑农 2 6’。     

Dynamics of Seed Protein Biosynthesis in Two Soybean Genotypes Differing in Drought Susceptibility

The dynamics of seed storage protein biosynthesis was studied under field conditions during two vegetative seasons. Two soybean (Glycine max L. Merr.) genotypes were examined: BOSA (drought tolerant) and L 121 (drought susceptible). Seed samples were taken from plants at three stages of seed maturation (50 and 70 d after flowering, and at full maturity). The earlier synthesis of the -subunit of the 7S protein occurred in the drought susceptible cultivar. We have not found such differences in the synthesis of the - and -subunits of the 7S protein. Our results did not confirm significant genotypic differences in protein composition of the mature seeds between the cultivars studied, but have pointed out to the differences in the dynamics of protein biosynthesis during seed maturation and desiccation.     

Penetration and Development of Meloidogyne incognita on Roots of Resistant Soybean Genotypes

Meloidogyne incognita penetration and development were studied in roots of highly resistant (PI 96354, PI 417444), resistant (Forrest), and susceptible (Bossier) soybean genotypes. Although more second-stage juveniles (J2) had penetrated roots of PI 96354 and PI 417444 than roots of Forrest and Bossier by 2 days after inoculation, fewer J2 were present in roots of PI 96354 at 4 days after inoculation. Juvenile development in all genotypes was evident by 6 days after inoculation, with the highest number of swollen J2 present in roots of Bossier. At 16 days after inoculation, roots of PI 96354 had 87%, 74%, and 53% fewer J2 than were present in roots of Bossier, Forrest, and PI 417444, respectively. Differential emigration of J2, not fewer invasion sites, was responsible for the low number of nematodes in roots of the highly resistant PI 96354. Some 72% of the J2 penetrating the roots of this genotype emerged within 5 days after inoculation, whereas 4%, 54%, and 83% emerged from roots of Bossier, Forrest, and PI 417444, respectively. Penetration of roots of PI 96354 decreased the ability of J2 emerging from these roots to infect other soybean roots.     

Sex-Related Responses of Populus cathayana Shoots and Roots to AM Fungi and Drought Stress

We investigated the impact of drought and arbuscular mycorrhizal (AM) fungi on the morphological structure and physiological function of shoots and roots of male and female seedlings of the dioecious plant Populus cathayana Rehder. Pot-grown seedlings were subjected to well watered or water-limiting conditions (drought) and were grown in soil that was either inoculated or not inoculated with the AM fungus Rhizophagus intraradices. No significant differences were found in the infection rates between the two sexes. Drought decreased root and shoot growth, biomass and root morphological characteristics, whereas superoxide radical (O₂–) and hydrogen peroxide content, peroxidase (POD) activity, malondialdehyde (MDA) concentration and proline content were significantly enhanced in both sexes. Male plants that formed an AM fungal symbiosis showed a significant increase in shoot and root morphological growth, increased proline content of leaves and roots, and increased POD activity in roots under both watering regimes; however, MDA concentration in the roots decreased. By contrast, AM fungi either had no effect or a slight negative effect on the shoot and root growth of female plants, with lower root biomass, total biomass and root/shoot ration under drought. In females, MDA concentration increased in leaves and roots under both watering regimes, and the proline content and POD activity of roots increased under drought conditions; however, POD activity significantly decreased under well-watered conditions. These findings suggest that AM fungi enhanced the tolerance of male plants to drought by improving shoot and root growth, biomass and the antioxidant system. Further investigation is needed to unravel the complex effects of AM fungi on the growth and antioxidant system of female plants.     

不同耐渍基因型芝麻在厌氧胁迫下根系的生理与结构变化

利用4种耐渍性不同的芝麻基因型,在厌氧胁迫条件下检测了根部无氧呼吸酶活性、内源乙烯含量并调查了根形态和解剖结构,以比较研究旱生植物耐渍性的主要机制。同时设计了田间分期多次淹水试验,观察早期淹水训练对芝麻生长和产量的影响。结果表明：耐渍种质的乙烯释放量在根中增加了6．06倍,茎中1．76倍,不定根数量增加了4．0～5．0倍,在初生根和不定根皮层形成典型的通气组织。非耐渍种质中未检测到乙烯变化,不定根数量增加了0．79～1．8倍,根中无明显的通气组织发生,但是乙醇脱氢酶(ADH)活性可增加4．2～9．3倍,高于耐渍种质。分期淹水试验以四对真叶期和初花期处理产量较高,与对照无显著差异,而终花期一次性淹水产量损失最大。综合分析认为,不定根增生和根皮层通气组织的形成是芝麻耐渍性的重要机制,根中内源乙烯的增加与结构适应变异有关。淹水训练能够有效地改善芝麻品种耐渍能力为结构适应提供了进一步的证据。     

干旱胁迫对大豆苗期生长发育和生理生态特征的影响

对土壤逐步干旱下大豆幼苗形态特征和生理生态特征的变化研究表明:随着胁迫强度的增加,大豆苗期的光合速率、蒸腾速率、气孔导度降低,且相互之间呈显著正相关;随着胁迫时间的延长,叶绿素含量和叶片含水量呈低-高-低的变化趋势;在胁迫初期,对干物质分配率的影响很小,随着胁迫时间的增加,差异越来越大;随着干旱胁迫天数和强度的增加,游离脯氨酸含量呈逐渐递增的趋势,尤其是重度胁迫下积累能力更强。     

Seismic Stress Responses of Soybean to Different Photosynthetic Photon Flux

Physical agitation applied as periodic seismic stress (shaking)reduced stem clongation, leaf expansion, and biomass accumulationby vegetative soybeans. Level of photon flux (PPF) influencedthe type and extent of plant response to mechanical stress.Plant parts responded differently as PPF varied between 135and 592 µmol m^–2 S^–1. Stem length was significantlyreduced by seismic stress at 135 µmol m^–2 s^–1but this effect was insignificant at higher PPFs. Reduced stemlength resulted from an inhibition of internode elongation.Stem diameter was unaffected by stress at the PPFs tested. Incontrast to effects on stem elongation, leaf area was insensitiveto stress treatments at 135 µmol m^–2 S^–1 butwas progressively inhibited by stress as PPF increased. Statisticallysignificant reductions in shoot f. wt and d. wt by seismic stressoccurred only at 295 µmol m^–2 S^–1. Root biomassaccumulation was not affected by seismic stress at any PPF usedin this study. Glycine max (L.) Merr. cv. Century 84, mechanical stress, photosynthetic photon flux, seismic stress, soybean     

大豆异黄酮对干旱胁迫下油菜幼苗生长的影响

研究在模拟干旱的条件下喷施大豆异黄酮对油菜(Brassica campestris)幼苗抗旱性的影响.结果表明:0.1 mg/L的大豆异黄酮处理过的油菜幼苗,叶绿素a含量是对照的1.69倍、硝酸还原酶和过氧化物酶活性分别比对照增强了52.85%和30.73%、类黄酮含量比对照增加了49.1%、丙二醛含量比对照降低了26.61%、根系活力比对照高出近1倍.上述结果表明低浓度的大豆异黄酮能明显减轻干旱胁迫对油菜幼苗生长的伤害作用.     

水分胁迫下不同进化型小麦抗氧化能力比较

以6种不同基因型小麦为试验材料,研究了水分胁迫下不同生长期小麦体内超氧化物歧化酶（SOD）活性以及超氧自由基（O2）含量变化,并分析了两者之间的相关关系。结果表明,水分胁迫下6种基因型小麦SOD活性及超氧自由基含量在拔节期和灌浆期均有不同程度的增加;栽培型品种SOD活性增幅高于野生型品种,超氧自由基增幅较低;同样,二粒小麦与一粒小麦相比,二粒小麦SOD活性增幅高于一粒小麦,超氧自由基增幅较低;但现代栽培小麦种表现不明显。结果说明,栽培型与野生型小麦相比,二粒小麦与一粒小麦相比,具有较强的抗氧化能力。