不同桃砧类型对淹水胁迫的生理响应及耐涝性评价

以1年生嫁接苗为试材,研究了3个桃砧对淹水胁迫生理响应的差异,并对9个桃砧种质进行了耐涝性评价。结果表明:随着淹水时间的延长,3个桃砧叶片受害症状逐渐加重,表现为涝害指数增加及根系活力降低、叶绿素含量降低、质膜透性和丙二醛含量升高、抗氧化酶活性先升高后降低等生理响应。毛樱桃具有较强的抗氧化能力及较低的涝害指数,根系活力和叶绿素含量降幅较小,质膜透性和丙二醛含量升幅较小,表现出较强的耐涝性;山桃与之相反,毛桃介于两者之间。基于根系活力、叶片质膜透性、丙二醛和叶绿素含量及抗氧化酶活性计算隶属函数值,综合评价出不同桃砧种质的耐涝性,其中GF43、毛樱桃、F4的耐涝性较强。上述结果为桃砧种质耐涝性评价提供了评价指标,同时筛选出耐涝性强的桃砧为生产利用提供参考。     

淹水胁迫对不同品种猕猴桃生理特性的影响

以美味猕猴桃“米良1号”、中华猕猴桃“红阳”和对萼猕猴桃“猫人参”组培苗为材料,观察淹水胁迫对不同品种猕猴桃植株形态的影响,并测定叶片中叶绿素、可溶性蛋白、脯氨酸(PRO)、丙二醛(MDA)含量以及过氧化氢酶(CAT)、过氧化物酶(POD)、超氧化物歧化酶(SOD)等酶的活性和抗氧化能力。结果表明,随着淹水时间的延长,“猫人参”猕猴桃受涝害程度小于其他2个品种,“猫人参”猕猴桃叶片中的总叶绿素含量变化幅度较小;3种猕猴桃叶片中的渗透调节物质可溶性蛋白、PRO和MDA不断增加,而叶片中的保护酶CAT、POD活性呈下降趋势。SOD活性在“米良1号”“猫人参”猕猴桃叶片中呈下降趋势,而在“红阳”猕猴桃叶片中呈增加趋势;其中“猫人参”猕猴桃叶片中的SOD活性高于其他2个品种,一直维持在较高水平,其总抗氧化能力也不断增强。不同品种间各指标变化趋势与幅度存在一定差异,以总抗氧化能力尤其明显,可作为衡量猕猴桃耐涝性的重要参考指标。     

无花果品种幼苗淹水胁迫的生理响应与耐涝性评估

为评估无花果耐涝性,以12个无花果品种扦插苗为材料,通过盆栽淹水方式探讨了完全淹水处理对叶片色素含量、抗氧化酶活性、活性氧代谢、丙二醛含量、脯氨酸含量、蛋白质含量以及叶绿素快速荧光特性等生理指标的影响。结果表明,淹水导致12个无花果品种叶片色素含量和可溶性蛋白含量显著低于对照,大部分品种叶片超氧阴离子产生速率、丙二醛（MDA）和脯氨酸含量显著高于对照,但不同品种变化幅度不同。另外,淹水胁迫影响无花果叶片叶绿素快速荧光特性,叶绿素快速荧光值（OJIP）、PSⅠ、PSⅡ反应中心活性和光合性能指数等多种参数变化均与品种耐涝性存在显著相关。根据品种涝害指数以及与其显著相关的生理指标,利用模糊聚类法进行分析,将102A、105A和121E划为耐涝性强品种,106A、113C、107B和112C划为耐涝性中强品种,101A、110C和114C为耐涝性较弱品种,117D和118D为不耐涝品种。     

11个鲜食葡萄品种应对淹水胁迫的光合响应及耐涝性评价

为探究淹水胁迫对鲜食葡萄形态和光合生理的影响,筛选耐涝种质,为易涝葡萄产区鲜食品种选择和耐涝品种选育提供理论依据,以11个主栽鲜食葡萄品种1年生幼苗为试材,通过模拟水涝胁迫的形式,研究不同品种在0、3、6、9、12、15 d持续淹水胁迫下的涝害指数和光合指标,采用隶属函数法对各个品种的耐涝性进行综合评价。结果表明：随着淹水胁迫持续进行,所有供试品种的涝害指数均呈现升高趋势,早霞玫瑰最高,淹水12 d即达到100%,夏黑最低,淹水15 d为40%;相对叶绿素含量、净光合速率、蒸腾速率、气孔导度、最大光化学效率均呈现逐步下降趋势,淹水15 d分别下降了15.8%～82.4%、59.2%～119.5%、62.1%～94.6%、67.3%～98.7%、4.1%～74.2%;而胞间CO2浓度呈现逐步上升趋势,至淹水第9 d上升了24.2%～122.6%;水分利用率呈现先升高后下降趋势,至淹水结束不同品种减少了29.8%～86.7%;进一步隶属函数法综合分析,11个葡萄品种耐涝能力由强到弱依次为夏黑（0.530）>阳光玫瑰（0.438）>深红无核（0.432）>克瑞森无核（0.4...     

不同桃砧木品种对淹水的光合响应及其耐涝性评价

 以10 个桃砧木品种（毛桃、毛桃2 号、山桃、筑波5 号、桃巴旦、陕西桃巴旦、Nemaguard、GF305、GF43 和GF1869）的1 年生苗为材料,对其在持续淹水胁迫下叶片的光合特性进行测定,发现不同品种的各项光合生理指标变化幅度不同。以各项指标的耐涝系数作为衡量指标,利用主成分分析将8个单项光合指标综合成2 个独立的综合指标,通过隶属函数分析将10 个品种划分为3 类：GF43 和GF1869强耐涝,毛桃、毛桃2 号、筑波5 号、桃巴旦、陕西桃巴旦、Nemaguard 和GF305 中等耐涝,山桃不耐涝。     

4种冷季型草坪草耐涝性的对比研究

研究北方地区有代表性的4种冷季型草坪草种在苗期水涝环境下其部分形态学、生理生化指标的变化特性,并对4种冷季型草坪草的耐涝性作出比较性的评价。     

阿坝苹果砧木资源的耐涝性研究

阿坝苹果砧木资源的耐涝性研究成明昊，李晓林（西南农业大学园艺系重庆６３０７１６）金强，谢晓黎，刘扬青，欧平贵（四川省阿坝州林业科学研究所）苹果树的耐涝性，取决于苹果砧木［１、２］，选择耐涝性强的苹果砧木，对于发展苹果生产具有重要意义。苹果砧木资源的耐...     

一氧化氮提高黄瓜幼苗耐涝性的探究

为了提高黄瓜幼苗的耐涝性,以100μmol·L~(-1)硝普钠(SNP)作为一氧化氮供体,研究了一氧化氮对淹水胁迫下黄瓜幼苗细胞质膜、光合特性和抗氧化酶活性的影响。结果表明,外源一氧化氮能抑制淹水胁迫期间黄瓜根质膜相对透性和丙二醛含量的增加,淹水8 d时,经SNP处理的黄瓜根质膜相对透性和丙二醛含量与对照分别达到显著和极显著差异;能延缓叶片叶绿素含量的下降,使淹水期间叶片能维持较高的光合能力,淹水8 d时,经SNP处理的黄瓜叶片叶绿素含量和光合速率极显著高于对照;外源一氧化氮能提高淹水胁迫时黄瓜根SOD、POD、CAT的活性,淹水8 d时,经SNP处理的黄瓜根SOD、POD活性与对照达到极显著差异,CAT活性与对照达到显著差异。研究表明外源一氧化氮能提高黄瓜幼苗的耐涝性。     

‘浙猕砧1号’对长期淹水处理的响应特征

【目的】分析葛枣猕猴桃优株‘浙猕砧1号’对涝害胁迫的响应机制,为猕猴桃耐涝砧木的筛选提供理论依据。【方法】以葛枣猕猴桃优株‘浙猕砧1号’组培苗为试材,通过人工模拟淹水试验,检测葛枣猕猴桃在长时间持续淹水过程中的生理反应及逆境相关基因的表达情况,探究葛枣猕猴桃对涝害胁迫的响应机制。【结果】在持续淹水过程中‘,浙猕砧1号’叶绿素含量有所下降;根系活力降低,气生根发生明显且活力旺盛;叶片气孔开度下降,气孔密度增加;超氧化物歧化酶(SOD)和过氧化物酶(POD)活性在淹水处理的中后期相对较高,H2O2活性和丙二醛(MDA)的含量呈先上升后下降的趋势。AcCIPK9和AcCIPK13在处理初期表现不明显,处理后期显著上调表达;AcERF4和AcERF5在处理42 d表达量达到最高;相关功能基因AcSAD、AcADH、AcHSP17.5、AcPDC1、AcGAD、AcLBD和AcHB1在涝害处理后期都有不同程度的上调表达。【结论】‘浙猕砧1号’在淹水处理过程中,气生根发生明显,保护酶迅速积累,地上部分与地下部分的比例优化,以及相关信号蛋白和功能基因响应,促使植株逐渐适应外界多水环境,并能承受52天的持续淹水,表现出良好的适应性及耐涝性。     

Physiological responses and relative tolerance by Chinese apple rootstocks to NaCl stress

The physiological responses and salt tolerance of apple rootstocks were evaluated under high salinity. Seedlings of 15 kinds of apple rootstocks were treated with 200 mM NaCl for 10 d to assess growth, biomass, and physiological responses. Under NaCl stress, their growth parameters decreased compared with the control, with the greatest changes in leaf number, plant height, and relative water content (RWC). In contrast, electrolyte leakage (EL) and activities of peroxidase (POD) and catalase (CAT) were increased. For most rootstocks, stress treatment decreased malondialdehyde (MDA) and soluble protein contents along with superoxide dismutase (SOD) activity. Their degree of salt tolerance was comprehensively evaluated based on salt injury index (SI), adversity resistance coefficients (ARC), and cluster analysis. Malus prunifolia Borkh cv. dongbeihuanghaitang, M. sieboldii Rehd cv. daguohongsanyehaitang, M. prunifolia Borkh cv. qiuzi, and M. xiaojinensis Cheng et Jia were salt-tolerant rootstocks, whereas M. prunifolia Borkh cv. yingyehaitang, M. micromalus Hemsl, and M. sieboldii Rehd cv. lushihongguo were salt-sensitive rootstocks. These differences in sensitivity were associated with variations in the activities of anti-oxidation enzymes and in the amount of organic osmotica.     

Growth responses and ion regulation of four warm season turfgrasses to long-term salinity stress

Increased need for salinity tolerant turfgrasses continues due to increased use of saline water for lawn irrigation and turfgrass establishment on highly saline soil in arid and seashore regions. Turfgrasses growing on saline soil suffer from long-term salinity stress, so this experiment was conducted to study the salinity tolerance, growth, and physiological responses of four warm season turfgrasses [including ‘Diamond’ zoysiagrass (Zoysia matrella (L.) Merr.), ‘Z080’ zoysiagrass (Z. japonica Steud.), ‘C291’ bermudagrass (Cynodon dactylon (L.) Pers), and ‘Adalayd’ seashore paspalum (Paspalum vaginatum Sw.)] to 9 months of salinity stress. Seven salinity levels of irrigation water (0, 90, 180, 360, 540, 720, and 900 mM NaCl) were applied to turfgrasses grown in plastic tubes in a glass room. The salinity tolerance decreased in the following order according to percent green leaf canopy area after 9 months of salinity treatments: ‘Diamond’ > ‘Adalayd’ > ‘C291’ > ‘Z080’. Leaf weight, leaf length, canopy height, shoot density were significantly affected by salinity treatments for all turfgrasses. However, leaf width and/or leaf number per shoot were not affected by salinity in all turfgrasses except ‘Diamond’. Leaf and/or root water contents were also little affected. As salinity increased, leaf and root Na⁺ concentrations and Na⁺/K⁺ rates increased significantly and K⁺ concentrations decreased significantly except that of ‘Adalayd’ leaf. ‘Diamond’ and ‘Z080’ could reduce Na⁺ accumulation in the leaves by salt secretion from salt glands, while ‘Adalayd’ could exclude Na⁺ from the leaves and accumulate K⁺ in the leaves. ‘C291’ exhibited both ion regulation mechanisms, but to much less extent. Different growth responses and ion regulation means of four turfgrasses reflected different salinity tolerance mechanisms.     

Citrus rootstock responses to water stress

Tolerance to drought-stress (DS) of the citrus rootstock Forner–Alcaide no. 5 (FA-5) was tested and compared with that of its parents, Cleopatra mandarin (CM) and Poncirus trifoliata (PT). Nine-month-old seedlings of CM, PT and FA-5 and 15-month-old grafted trees of ‘Valencia’ orange scions on these three rootstocks were cultivated in sand under glasshouse conditions and irrigated with a nutrient solution. Plants were drought-stressed by withholding irrigation until leaves were fully wilted. Survival time of both seedlings and grafted trees under DS was linked to the water extraction rate from the soil, which depended mainly on leaf biomass and on transpiration rate. Seedling responses to DS affecting leaf water relationships and gas exchange parameters varied among genotypes. FA-5 seedlings survived longer than the other seedlings, maintaining the highest levels of water potential, stomatal conductance, transpiration rate and net CO₂ assimilation towards the end of the experiment, when water stress was most severe. Thus, FA-5 was more resistant to DS than its parents (CM and PT). Moreover, rootstock affected the performance of grafted trees under water stress conditions. The higher drought tolerance induced by FA-5 rootstock could be related to the greater osmotic adjustment (OA), which was reflected by smaller reductions in leaf relative water content (RWC) and in higher turgor potentials and leaf gas exchange than the other rootstocks.     

越冬期软枣猕猴桃田间冻害调查及抗寒生理

以五年生软枣猕猴桃品种'魁绿'丰绿'和'96-6'为试材,采用田间调查和比较分析的方法,研究了自然越冬期间3种软枣猕猴桃的田间冻害情况及其一年生枝条含水量、渗透调节物质含量及保护酶活性的变化,明确不同品种软枣猕猴桃对低温的适应能力及其内在的生理机制,以期为东北地区软枣猕猴桃抗寒品种的选育提供参考依据.结果 表明:根据田间冻害调查和冻害指数可以判断出,3种软枣猕猴桃的抗寒性强弱顺序依次为'魁绿'＞'96-6'＞'丰绿'.随着冬春季节气温的先降低后升高,软枣猕猴桃一年生枝条内的组织含水量呈先降低后升高的趋势,束缚水/自由水比值、可溶性糖含量、可溶性蛋白质含量、游离脯氨酸含量、超氧化物歧化酶(SOD)活性、过氧化物酶(POD)活性和过氧化氢酶(CAT)活性均表现出不同程度的先升高后降低.综上所述,在自然越冬的各个时期,'魁绿'的各项生理指标值在3个供试品种中最高,'丰绿'的最低,'96-6'处于二者之间,这与各品种的抗寒性强弱顺序一致.     

4个品系软枣猕猴桃花期不同程度新梢摘心的效应

以4个品系软枣猕猴桃LD107、LD133、LD243、LD1214为试材,在花期分别对营养梢、结果梢进行摘心处理,研究不同摘心程度的效应。结果表明,花期新梢摘心处理能提高摘心梢翌年的萌芽率及结果枝率,LD107、LD243、LD1214这3个品系的营养梢留30cm,结果梢留7叶摘心更有利于提高结果枝率,LD133品系营养梢留50cm,结果梢留3叶摘心更有利于形成结果枝;新梢摘心后形成的营养枝率无显著差异。     

莲雾对低温胁迫的生理响应及抗寒性分析

【目的】探讨莲雾低温胁迫下的生理变化规律。【方法】以‘农科一号’莲雾为试材,测定了低温胁迫下叶片相对电导率(REC)、丙二醛(MDA)含量、过氧化物歧化酶(SOD)、过氧化氢酶(CAT)、过氧化物酶(POD)活性、束缚水(BW)、自由水(FW)、脯氨酸(Pro)及可溶性糖(WSS)含量的变化趋势。【结果】随着温度的下降及低温时间的延长,莲雾叶片相对电导率上升;MDA含量增加;SOD、CAT和POD分别在4℃处理3 h、1℃处理6 h和4℃处理9 h时活性最高,均在-5℃处理12 h时活性最低;束缚水含量在3 h、6 h和9 h处理中随温度降低而升高,而12 h处理的变化与之相反;脯氨酸和可溶性糖含量均随温度下降呈降-升-降变化。【结论】‘农科一号’莲雾的半致死温度(LT50)为-1.2℃,叶片在低温胁迫过程中细胞膜质过氧化加剧,MDA累积,电解质外渗,束缚水、脯氨酸、可溶性糖等渗透调节物质在胁迫的不同阶段起到不同程度的保护作用,主要保护酶为过氧化氢酶和过氧化物酶。