干旱胁迫对不同苦荞品种苗期生长和根系生理特征的影响

采用盆栽人工控水试验,研究了不同水分处理(正常供水、中度干旱和重度干旱)对耐旱型(‘迪庆苦荞’、‘西农9909’)和不耐旱型(‘西荞1号’和‘黑丰1号’)苦荞品种苗期生理、形态指标的影响,并通过隶属函数法与主成分分析对品种抗旱性进行综合评价,以揭示苦荞苗期的抗旱生理机制。结果表明:(1)与正常供水相比,除‘迪庆苦荞’和‘西农9909’在重度干旱胁迫下主根长呈升高趋势外,其余苦荞品种在2个干旱条件下的株高、茎粗、叶面积、地上部干重、地下部干重、根系体积、根系表面积均呈下降趋势,且耐旱品种降幅小于不耐旱品种;重度干旱胁迫使得‘迪庆苦荞’的根冠比升高,而其余品种根冠比在干旱胁迫下均无显著变化。(2)干旱胁迫使苦荞叶片的叶绿素含量、相对含水量、最大荧光产量(Fm)、最大光化学效率(Fv/Fm)、根系活力和可溶性蛋白含量显著降低,而根系超氧化物歧化酶(SOD)活性、过氧化物酶(POD)活性、丙二醛(MDA)、可溶性糖及游离脯氨酸含量呈升高趋势;不同抗旱性品种间的升降幅度存在差异。(3)各苦荞品种耐旱能力综合评价值(D)表现为‘迪庆苦荞’‘西农9909’‘黑丰1号’‘西荞1号’;幼苗株高、地下部干重及根系SOD活性和蛋白质含量与D值呈显著正相关关系,而根系脯氨酸含量和可溶性糖含量与D值呈极显著正相关关系。研究发现,在中度与重度干旱逆境下,苦荞品种‘迪庆苦荞’和‘西农9909’综合表现较好,具有更强的耐旱能力,而品种‘西荞1号’和‘黑丰1号’综合表现较差,其抗旱性较弱;苗期株高、地下部干重以及根系SOD活性、蛋白质含量、脯氨酸含量和可溶性糖含量可作为苦荞抗旱性快速鉴定的指标。     

Identification of Genomic Regions Associated with Agronomical Traits of Bread Wheat Under Two Levels of Salinity Using GWAS

Plant Molecular Biology Reporter - Soil salinity is a major environmental stress that adversely affects the growth, development, productivity, and quality of crop species, in particular, in arid...     

不同抗盐性小麦叶鞘的Na+/K+选择性

以200mmol／LNaCl处理耐盐小麦（Triticum aestivum L．）品种DK961和盐敏感小麦品种LM153d后,DK961叶鞘中Na^＋含量和叶片中K^＋含量均显著高于LMl5,这造成DK961叶片中Na^＋／K^＋比显著低于LM15。即DK961的叶鞘以其较LM15更强的限制Na^＋、推动K^＋向叶片运输的能力来保持叶片相对较低的Na^＋／K^＋比,即叶鞘在小麦抗盐性中可能起重要作用。     

Assessment of Changes in Some Biochemical Traits and Proteomic Profile of UCB-1 Pistachio Rootstock Leaf under Salinity Stress

Journal of Plant Growth Regulation - University of California at Berkeley I or UCB-1 pistachio rootstock is propagated from the cross between Pistacia integerrima male × Pistacia...     

3个山茶品种对干旱胁迫的生理响应

以山茶(Camellia japonica)品种‘红露珍’、‘六角大红’和‘烈香’两年生扦插盆栽苗为试材,进行干旱胁迫试验,测定3个山茶品种在干旱胁迫下叶片相对含水量、叶绿素含量、丙二醛(MDA)含量等7种生理生化指标,分析不同山茶品种的生理响应,通过隶属函数法综合评定不同山茶品种的抗旱性。结果表明,3个山茶品种抗旱能力由强到弱依次为‘六角大红’>‘红露珍’>‘烈香’。     

14个荔枝品种的叶片性状分析

以东莞现栽14个荔枝品种为研究对象,对其比叶面积、叶干物质含量和叶片SPAD值等特征进行研究。结果表明,果皮龟裂片尖突、平坦、隆起等3种类型中,尖突类型的3个荔枝品种的比叶面积显著大于平坦类型的2个品种;隆起类型的9个荔枝品种的比叶面积大小不一,其中5个品种的比叶面积大于平坦类型的‘黑叶’品种,另外4个品种的比叶面积小于‘黑叶’。14个荔枝品种中,除了‘黑叶’外,其余13个品种的比叶面积和叶干物质含量均呈负相关关系;‘水晶球’和‘大丁香’的比叶面积和叶片SPAD值间呈正相关关系,其余12个品种的比叶面积和叶片SPAD值间均为负相关关系。     

Physiological Characteristics and Alternative Respiratory Pathway under Salt Stress in Two Wheat Cultivars Differing in Salt Tolerance

Changes in respiratory pathway, dry weight, contents of proline, ATP, Na⁺and K⁺were investigated under five salinity treatments in the leaves of plants of spring wheat (Triticum aestivumL.). Two cultivars differing in salt resistance, namely, 89122 (salt-tolerant) and Longchun13 (salt-sensitive), were used. The decrease in dry weight and K⁺content was observed with the increasing NaCl concentrations, but more in cv. 89122 plants than in Longchun13 plants. Contents of proline and Na⁺in both cvs increased greatly, but the former increased more in 89122 while the latter more in Longchun13 plants. In all salinity treatments tested, a salt-induced increase in the activity of the alternative pathway was found, although cytochrome pathway (CP) still remained the main electron transport pathway. ATP production changed in parallel with CP operation. Cv. 89122 plants could produce more ATP than cv. Longchun13 plants exposed to each salinity treatment and their ATP generation could even be stimulated in contrast to its rapidly decline in Longchun13 plants with increased salinity stress. The possible relationship between respiration metabolism and above mentioned physiological changes is discussed.     

Cd~(2+)胁迫对小麦幼苗生理生化特性的影响

以小麦品种'西旱2号'和'宁春4号'幼苗为材料,采用室内水培实验研究了不同浓度Cd(NO3)2处理对叶绿素含量、抗氧化酶活性及渗透性调节物含量等的影响.结果表明,两小麦品种幼苗的叶绿素a(Chl a)、叶绿素b(Chl b)及叶绿素总量在镉胁迫下均比对照降低,且高浓度镉对'西旱2号'幼苗叶片Chl b的破坏程度强于Chl a;两品种镉胁迫幼苗的过氧化氢酶(CAT)、过氧化物酶(POD)和抗坏血酸过氧化物酶(APX)活性均比对照不同程度地升高;两品种镉胁迫幼苗的可溶性糖含量均与对照无显著差异,但'宁春4号'幼苗叶片的脯氨酸含量却比对照显著升高,且此效应具有浓度依赖性;镉胁迫下两品种小麦幼苗叶片的MDA含量变化与对照无显著差异.研究显示,两品种小麦幼苗叶片的光合色素在镉胁迫下均受到不同程度的破坏,但它们均能通过增加体内保护酶活性和渗透调节物质含量来缓解膜脂过氧化伤害,从而对镉胁迫均表现出较强的耐受能力.     

低温胁迫对不同西葫芦品种幼苗生长与生理特性的影响

在昼/夜温度为10℃/5℃的低温胁迫下,对‘特早’、‘早青’、‘冬宝’3个西葫芦(Cucurbit pepoL.)品种的幼苗生长和生理生化指标的变化规律进行研究。结果表明,随着低温处理时间的延长,幼苗单株叶面积、单株干重均有一定程度下降,叶绿素总含量也呈下降趋势;各品种的根系活力显著下降,电导伤害率均明显升高;丙二醛含量在处理9 d时有所下降但整体呈现缓慢上升的趋势,脯氨酸含量呈现逐渐上升的趋势,且处理6 d是脯氨酸和丙二醛两指标测定的理想时期;处理幼苗的POD活性呈"V"字形变化趋势,抗寒性强的品种酶活性也较高,CAT和SOD活性则呈现出先上升后下降的趋势,三者活性均显著高于相应对照,且以处理6 d时酶活性受影响最大。各测定指标间表现出一定的交叉适应和协调性。研究发现,西葫芦耐冷性强弱可根据幼苗电解质渗透率结合根系活力或干物质积累来综合评判,品种‘冬宝’对低温具较强耐受性。     

河北省小麦品种基于农艺性状的遗传多样性分析

为明确河北省小麦品种遗传多样性的基础和历史演变,本研究以所收集的该省近60年来审(认)定的125个小麦品种为研究材料,以8个农艺性状为基础进行了遗传多样性分析.结果表明:河北省小麦品种农艺性状变异比较丰富,以每穗不孕小穗数的变异系数最高(52.63%),其次为单株粒重和有效分蘖数,每穗小穗数的变异最小;多样性指数从20世纪70年代的1.62增加到目前的1.89,平均值为1.76,但略低于其他省份.在上述分析基础上,用最长距离法可将125份材料聚为3大类,其中80.8%(101个)的品种归入第3大类,主要为20世纪90年代以后的品种.这说明该省小麦品种遗传多样性在逐步提高的同时,其遗传基础仍需进一步拓宽.     

Comparison of Hexaploid and Tetraploid Wheat Cultivars in their Responses to Water Stress

We studied the effect of water stress imposed at anthesis and pre-anthesis stages on oxidative stress and antioxidant activity in four wheat cultivars, two hexaploid Triticum aestivum cultivars, drought resistant cv. C 306 and drought susceptible cv. Hira, and two tetraploid cultivars, T. durum cv. A 9-30-1 and T. dicoccum cv. HW 24. Water stress decreased relative water content (RWC), membrane stability index (MSI), and increased H₂O₂ and malondialdehyde (MDA) contents as well as activity of superoxide dismutase (SOD), catalase (Cat) and peroxidase (POX) in all the genotypes at all the stages. Both the tetraploid cultivars showed higher RWC, MSI and SOD activity, and lower H₂O₂ and MDA contents under water stress than hexaploid ones. Cat and POX activities were highest in C 306.     

水分胁迫下小麦叶片的电容与水分含量关系

以6个冬小麦品种的幼苗为材料,测定了它们在不同PEG胁迫时间下对叶片总含水量、束缚水/自由水比值和电容值进行测定,并对其叶片水分参数与叶片的电容值的变化及其相关性进行比较分析。结果显示:随着干旱胁迫程度的逐渐加重,小麦叶片的生理电容值在0.1～100.0kHz内均逐渐变小,且以5kHz为最适测定频率;各小麦品种的叶片含水量、束缚水/自由水比值、电容值均随着干旱胁迫时间的延长而逐渐降低,并以抗旱性较强品种叶片的值较高且降低幅度较小;干旱胁迫下各冬小麦品种叶片电容值与其相应含水量呈极显著正相关关系(P<0.01),其相关系数为0.850～0.994。表明,生理电容值能较灵敏地反映小麦叶片含水量的变化,可作为表征小麦叶片水分参数变化的一项灵敏指标,干旱胁迫下小麦品种叶片电容值变化大小可以反映其抗旱性强弱及其受旱程度。     

黄淮麦区小麦子粒多酚氧化酶活性基因等位变异的分子检测

摘要: 籽粒多酚氧化酶（Polyphenol oxidase,PPO）活性是造成面粉以及面制品褐变的主要因素,了解不同小麦品种籽粒PPO活性基因的等位变异情况,有助于遗传改良中提高面制品的外观品质。本研究利用2A染色体上Ppo-A1的标记PPO18以及2D染色体上Ppo-D1的标记PPO16和PPO29检测该基因在118份黄淮麦区小麦品种中的等位变异。结果表明：在Ppo-A1位点,48.3％的小麦品种含Ppo-A1a（高PPO活性）型等位基因,51.7％的小麦品种含Ppo-A1b（低PPO活性）型等位基因,Ppo-A1a和Ppo-A1b两者之间的差异达到显著水平（P﹤0.05）。在Ppo-D1位点,55.1％的小麦品种含Ppo-D1a（低PPO活性）型等位基因,44.9％的小麦品种含Ppo-D1b（高PPO活性）型等位基因,Ppo-D1a和Ppo-D1b两者之间的差异也达到显著水平（P﹤0.05）。在Ppo-A1和Ppo-D1两个位点共检测到Ppo-A1a/Ppo-D1a（中间型PPO活性)、Ppo-A1a/Ppo-D1b（高PPO活性）、Ppo-A1b/Ppo-D1a（低PPO活性）、Ppo-A1b/Ppo-D1b（中间型PPO活性）四种变异组合类型,分布频率分别为28.8％、19.5％、26.3％和25.4％,彼此之间的差异均达到显著水平（P﹤0.05）。总体来看,这三个基因特异性标记可以快速、准确和方便的检测籽粒PPO基因的不同等位变异。此外,本研究检测出部分材料具有低PPO活性,可为选育具有低PPO活性的小麦品种提供有用信息。     

AFLP-Based Genetic Diversity and Its Comparison with Diversity Based on SSR, SAMPL, and Phenotypic Traits in Bread Wheat

Data on AFLP (eight primer pairs) and 14 phenotypic traits, collected on 55 elite and exotic bread wheat genotypes, were utilized for estimations of genetic diversity. We earlier used these 55 genotypes for a similar study using SSRs and SAMPL. As many as 615 scorable AFLP bands visualized included 287 (46.6%) polymorphic bands. The phenotypic traits included yield and its component traits, as well as physiomorphological traits like flag leaf area. Dendrograms were prepared using cluster analysis based on Jaccard's similarity coefficients in case of AFLP and on squared Euclidean distances in case of phenotypic traits. PCA was conducted using AFLP data and a PCA plot was prepared, which was compared with clustering patterns in two dendrograms, one each for AFLP and phenotypic traits. The results were also compared with published results that included studies conducted elsewhere using entirely different wheat germplasm and our own SSR and SAMPL studies based on the same 55 genotypes used in the present study. It was shown that molecular markers are superior to phenotypic traits and that AFLP and SAMPL are superior to other molecular markers for estimation of genetic diversity. On the basis of AFLP analysis and keeping in view the yield performance and stability, a pair of genotypes (E3876 and E677) was recommended for hybridization in order to develop superior cultivars.     

河南小麦新品种的春化基因型鉴定

为了了解河南省最新培育小麦品种春化基因的等位变异状况,本研究利用分子标记技术对河南省新培育的50份冬小麦新品系(种)的春化基因Vrn-A1、Vrn-B1、Vrn-D1和Vrn-B3位点的等位变异组成进行了鉴定和分析。结果表明,所有参试小麦品种的Vrn-B3位点基因型均表现为隐性,48份小麦品种的Vrn-A1和Vrn-B1位点基因为隐性,42份小麦品种的Vrn-D1位点基因为隐性,说明隐性基因在河南小麦中占据主导地位。其中,豫农2019、豫农2020、豫农2071、国麦301、平安08-8、百农69、囤麦3698、08漯33共8个小麦品种的Vrn-D1位点基因均为显性的Vrn-D1a类型。小麦品系豫农2053和豫农3052的Vrn-A1和Vrn-B1位点的春化基因均表现为缺失,进一步研究表明,这2份小麦新品系仍能正常开花,但开花期比对照周麦18分别晚1d和2d,因此Vrn-A1和Vrn-B1并非小麦开花的必需基因。本研究将为黄淮麦区广适、高产小麦新品种的选育和推广提供参考。     

Molecular Analysis of Soybean Cultivars Differing in Response to Salinity Stress

Forty-seven soybean cultivars differing in response to sodium chloride were analyzed with 37 SSR markers for genetic diversity estimation. Thirty-two (86.5 %) out of 37 markers were polymorphic. The number of alleles ranged from 2–7 for different polymorphic markers, whereas the polymorphic information content (PIC) ranged from 0.061 to 0.793 with an average of 0.549. Average genetic similarity coefficient was 0.281. UPGMA based cluster analysis placed cultivars into five main clusters. In addition, the Mantel’s test for cophenetic correlation with r = 0.878 indicated good fit of the cultivars to a group in the cluster analysis. No clear pattern was observed between major clusters and place of release or targeted area of the cultivars. Genetically diverse cultivars were identified that could be potentially important sources of the germplasm for the development of salt tolerant cultivars in soybean.