红花种子萌发期抗旱性鉴定与评价

为了探索红花耐旱机制及为选育耐旱品种提供理论依据,本文研究了干旱胁迫对红花种质萌发及生长状况的影响。采用聚乙二醇(PEG-6000)模拟干旱胁迫处理,对干旱胁迫下10个红花种质萌发率及幼苗生长指标进行测量,并对各测量指标进行模糊隶属函数分析。结果表明低浓度的PEG对红花种子萌发有一定程度的促进作用；当浓度为15%时,对各指标的抑制作用明显,因此本研究选用15%的PEG浓度鉴定红花种质的抗旱性。在干旱胁迫下红花发芽势、发芽率、下胚轴重、子叶重等降低,胚芽生长受到抑制,干旱对不同种质的根长和根重的影响不一致。通过种子萌发抗旱指数及隶属函数值对红花种质萌发期抗旱性进行综合评价,其中BXY1465为萌发期抗旱性强的材料,BXY512、BXY426、BXY1466以及BXY1859属于萌发期抗旱性中等的材料,BXY1805、BXY2527、BXY2110、BXY750以及WH0086属于萌发期抗性弱的材料。     

基于主成分分析的不同棉花品种低温萌发关键期研究

为明确低温为害棉花种子萌发过程的关键期,以新陆中46号、新陆早57号、新陆早74号和新陆早82号为试验材料,25℃为对照温度,通过室内发芽试验,研究12℃低温处理下4个棉花品种在种子萌发过程中种子活力指标变化和胚根生长情况。结果表明,12℃低温处理能降低棉花种子活力和抑制胚根生长,不同品种间耐低温能力存在差异,新陆早57号低温耐受力最强。7个测定指标间均存在正相关关系,发芽指数与活力指数、胚根鲜重与胚根干重间相关性最大,发芽势与胚根长、发芽指数与胚根长间相关性最小。不同棉花品种各处理主成分综合得分排序为T 2相似文献   

低温胁迫和赤霉素对花生种子萌发和幼苗生理响应的影响

低温是影响我国广大花生产区春花生发芽的主要因素之一。本文以不同生态区的30个花生品种为实验材料,研究了倒春寒天气诱导的低温胁迫对花生出苗的影响,以出苗率为标准筛选出4个耐低温的花生品种(阜花17、阜花12、冀花16、冀花18)和4个不耐低温的品种(鲁花11、白沙1016、正农黑花生1号、白玉)于温室测定了4℃低温和赤霉素(GA_3)处理后种子发芽相关指标和幼苗生理指标。结果表明, 4℃对耐低温花生品种发芽率、发芽指数影响不显著,但种子活力指数和芽长呈现下降趋势;4℃处理后,不耐低温品种幼苗相对膜透性和MDA含量上升幅度更高,耐低温品种幼苗的可溶性糖和游离脯氨酸含量上升幅度更大。GA_3显著促进4℃低温处理后花生种子萌发和种子活力,抑制了花生幼苗在低温处理后相对膜透性和丙二醛的上升,提高了可溶性糖、可溶性蛋白、游离脯氨酸含量。研究表明,赤霉素促进低温胁迫下种子萌发和幼苗生长的最佳浓度是300μmol L~(–1)。发芽率与相对膜透性和丙二醛含量显著负相关,与可溶性糖、脯氨酸含量显著正相关。温度影响发芽率的品种间差异较大,常温下赤霉素对不同耐低温品种的发芽率影响较小。本研究为耐低温花生种质资源创新和新品种培育提供了理论依据,为研究赤霉素对不同花生品种耐低温性影响的生理机制提供了基础。     

盐胁迫对40份藜麦种质种子萌发的影响及其耐盐性评价

为明确盐胁迫对藜麦种质材料种子萌发的影响,本试验以40份来自不同省份的耐盐性藜麦种质为材料,设置0、100、200、300、400和500 mmol/L NaCl处理,测定种子萌发期的发芽率、发芽势、胚轴长、胚根长和鲜重,并采用相关性分析和隶属函数相结合的方法,筛选耐盐性较强的材料。结果表明,与对照相比,随盐浓度升高,40份藜麦种质发芽率、发芽势、胚轴长、胚根长和鲜重均呈先升高后降低的趋势;通过对各指标进行相关性分析,发现鲜重与发芽势呈极显著(P<0.01)正相关;对40份藜麦种质进行隶属函数、聚类分析和综合评价后,将供试材料分为三大类,即强耐盐、中度耐盐和敏盐材料,筛选出强耐盐材料4份,分别为‘JSS L-2’、‘HJL34-1’、‘HJL-33-2’和‘白藜’;敏盐材料4份,分别为‘HZL-1-3’、‘HZLM 5-3’、‘HZLM11-2’和‘MLL-3’。本研究结果可为藜麦耐盐新品种的选育提供理论依据。     

宁夏设施番茄主栽品种芽期和苗期抗寒性评价

以9个不同番茄品种在低温下的发芽特性及苗期的冷害指数,综合评估其耐冷性,以期为生产上筛选抗寒性强的品种提供依据。试验结果,表明“嘉粉8346”和“爱吉168”均表现为耐低温较强的品种。     

不同棉花基因型种子萌发响应铜胁迫的差异

在铜污染耕地种植棉花对提高耕地利用效率和棉农收入具有重要意义,但铜胁迫对棉花种子萌发的影响仍不清楚。以7个陆地棉品种（系）为试验材料,设置0、10、100和2 000μmol/L 4个Cu²⁺浓度处理进行发芽试验,记录10d后棉花种子的发芽率和幼苗的鲜重、根长和芽长。以幼苗鲜重、根长和芽长为指标,采用耐性指数和隶属函数对不同品种（系）种子的耐受性进行综合评价。结果表明,在Cu²⁺浓度10~2 000μmol/L范围内随着浓度的升高,幼苗鲜重、根长和芽长所受抑制增强,且根长的受抑制程度高于芽长。在中低浓度下（10~100μmol/L）能将不同基因型种子萌发对铜胁迫的耐受性较好地区分开来,鄂抗棉10号的耐性指数和隶属函数平均值均居首位,而SGK321均居末位。研究结果初步表明,鄂抗棉10号为铜胁迫钝感基因型,而SGK321为敏感基因型。     

新疆春小麦品种萌发期抗旱性评价

研究干旱胁迫条件下新疆春小麦不同品种间抗旱性的差异。以20% PEG-6000 作为水分胁迫剂,对10个新疆春小麦品种的发芽率、发芽势、相对芽长、相对根长、相对发芽率、萌发抗旱指数进行研究分析,并通过加权隶属函数法对供试材料的抗旱性进行了综合评价。结果表明：1)与对照相比,20%浓度的PEG胁迫后,发芽率、发芽势、相对芽长、相对根长、相对发芽率均受到抑制,不同品种降幅不同;2) 通过隶属函数法对上述指标进行综合评价分析,10份春小麦的综合评价值(D值)在0.01~0.82之间,中国春为强抗旱品种(1级),新春3号、新春6号、新旱688等3个品种为中抗品种(2级),新春2号、新春26号等2个品种为弱抗旱品种(3级),新春7号、新春17号、新春20号、新春21号等4个品种为不抗旱品种(4级)。因此,新旱688、新春3号、新春6号可作为新疆小麦抗旱育种的种质资源。     

Identification of Resistance to Tetranychus turkestani and Analysis of Leaves Surface Wax of Different Cotton Varieties (Lines) in Xinjiang

[Objective] Based on the representative 236 cotton varieties in Xinjiang, the resistance of cotton to mites was identified, and the waxy content and waxy components of leaves were analyzed to lay a foundation for cotton breeding. [Method] In the cotton seedling stage, the waxy content of the leaves of different cotton varieties was determined, and the waxy components of the leaves were analyzed by gas chromatography-mass spectrometry. [Result] Most cotton varieties are sensitive to the damage of cotton mites. There were 2 high resistance varieties, 3 resistant materials, 22 medium resistant materials, 207 sensitive materials and 2 high-sensitivity materials in 236 cotton materials. The waxy content on the surface of cotton leaves was significantly negatively correlated with leaf damage levels. The waxy components of cotton leaves were mainly alkane compounds, containing a small amount of esters, ethers and fatty acids. The content of alkanes and esters in waxy leaves of high-resistance cotton germplasm materials was higher than that of high-sensitivity materials. The compound with the largest difference in content are C₂₄H₅₀, C₃₅H₇₂ and C₁₇H₃₆. [Conclusion] These results lay a foundation for further study on the effects of waxy content on host selection and mite resistance of cotton mites.     

Effects of Low Phosphorus Stress on Root Morphology and Physiological Characteristics of Different Cotton Genotypes at the Seedling Stage

[Objective] Phosphorus is one of three major required nutrients for cotton growth and development. A phosphorus deficiency will lead to retarded cotton growth, undeveloped roots, and the abscission of buds and bolls, which results in serious reductions in cotton yield and quality. While applied phosphorus is easily fixed in soils, it is mostly transferred to occluded P, which is not available to plants. Therefore, this study aimed to provide theoretical support for the study of response mechanisms to low phosphorus stress and the efficient phosphorus uptake and utilization of different cotton genotypes. [Method] The effects of phosphorus accumulation and utilization, leaf photosynthetic characteristics and root morphology of two genotypes of cotton (CCRI 79 and SCRC 28) were studied in hydroponic cultures having different phosphorus concentrations. [Result] CCRI 79 had higher phosphorus utilization rates of 90.92 mg·mg^－1 at the low phosphorus level (KH2PO4 1.0×10^－5 mol·L^－1) and 23.09 mg·mg^－1 at the high phosphorus level (KH2PO4 0.5 mol·L－1) compared with SCRC 28. When phosphorus was deficient, the total root length, total root surface area and total root volume of SCRC 28 increased by 13.05%, 18.78% and 10.50%, respectively, while the total root length, total root surface area and total root volume of CCRI 79 decreased significantly. [Conclusion] Here, we found that SCRC 28 had a root morphology and physiological characteristics that allowed it to adapt to low phosphorusstress, while CCRI 79 utilized phosphorus more efficiently.     

不同浓度盐胁迫对小麦萌发和幼苗生长的影响

提高以盐渍化为代表的中低产田的产量,已成为进一步提高小麦总产量的主要途径,对于保障中国粮食安全具有重要意义。笔者依据300 mmol/L盐浓度下的发芽率和水培苗期在200 mmol/L和400 mmol/L两个盐浓度梯度水平下的株高、根长、根数变化,对选自不同生态类型区的21份冬小麦资源及育成品种进行了耐盐性鉴定,并依据盐胁迫下的小麦发芽率和苗期植株变化对供试材料的耐盐力进行综合评判。研究结果表明：从供试材料中筛选出了1级耐盐材料3份;2级耐盐材料3份;3级耐盐材料5份,丰富了小麦耐盐种质资源。该方法与田间盐池鉴定方法相比,具有工作量小、速度快的优点,且鉴定结果与田间表现吻合度高,研究结果可为小麦耐盐育种提供理论和技术支撑,同时也可为进一步提高盐渍化土壤小麦产量提供技术支撑。     

Isolation and Characterization of GhLEA3 Gene from Upland Cotton and Its Expression in Response to Low Temperature Stress

[Objective] Based on the analysis of cotton GhLEA3 gene structure and its expression model in chilling stress, we investigated the resistance function of GhLEA3 in response to cold stress. [Method] We cloned GhLEA3 from upland cotton by homologous sequence cloning way. We analyzed the properties of the GhLEA3, and constructed phylogenetic tree by bioinformatics analysis. We constructed the transient expression vector 35S∷GhLEA3-GFP by In-Fusion connection technology and studied the subcellular localization of GhLEA3. The expression of GhLEA3 gene in leaves of TM-1 at three-leaf stage under low temperature stress treatments (4 ℃, 24 h) was performed. Agrobacterium tumefaciens mediated floral dipping method was used to transform the gene with expression vector 35S∷GhLEA3-GFP into Arabidopsis thaliana wild type. Low temperature germination experiment at 4 ℃ was conducted to verify germination ability of the transgenic Arabidopsis thaliana T₃ seed. The transgenic Arabidopsis seedlings were treated at 4 ℃(low temperature), and all the leaves were taken to measure their electrical conductivity. [Result] The coding sequence of GhLEA3 gene is 1 218 bp, which encodes 405 amino acids. GhLEA3 protein includes 4 functional domains of PF02987. Phylogenetic analysis showed that the similarity of amino acid sequences between upland cotton GhLEA3 and Arabidopsis thaliana AtLEA3 was 52.6%. GhLEA3 might be mainly localized in vacuoles and small vesicles. GhLEA3 was up-regulated in leaves after low temperature treatment. The germination rate of transgenic Arabidopsis thaliana of T₃ generation at low temperature was significantly higher than that of wild type, and its electrical conductivity of leaves after low temperature treatment was significantly lower than that of wild type. [Conclusion] GhLEA3 belonged to the member of LEA3 family. Phylogenetic analysis showed that GhLEA3 had the closest relationship with AtLEA3. GhLEA3 was induced by low temperature stress and may play an important role in improving cold resistance.     

玉米自交系芽期耐冷性鉴定

低温冷害是北方春玉米区主要的气象灾害之一。通过种子低温发芽试验对8个东北地区生产上主要利用的玉米自交系进行芽期耐冷性鉴定。在常温（25℃）和低温（10℃）条件下分别测定了发芽势、发芽率、平均发芽时间、发芽指数、幼苗干重和活力指数等,并以各性状低温与常温下测定值的比值（相对值）作为耐冷性鉴定指标。通过聚类分析将自交系分为耐冷性强中弱3类,其中PH4CV、吉419和吉495耐冷性强,H21耐冷性中等,W9706、黄早四、丹黄02和四279耐冷性弱。相关性分析表明,相对发芽率、相对发芽指数、相对幼苗干重与相对活力指数呈极显著相关,可以作为玉米自交系芽期耐冷性鉴定指标。本试验为大规模鉴定和筛选芽期耐冷玉米种质奠定了基础。     

52份豌豆种质萌发期耐铝毒性的综合评价与筛选

随着土壤酸化的日益加重,铝毒成为影响作物种子萌发质量以及产量的重要胁迫因子之一。本研究采用单项耐铝毒系数(AC值)、综合耐铝毒系数(CAC值)、平均隶属函数值(ASF值)、耐性综合评价值(A值)等指标及相关分析、主成分分析、聚类分析和逐步回归分析等方法,综合评价豌豆种质萌发期铝毒耐性,建立综合筛选评价体系,并筛选萌发期耐铝毒豌豆种质。利用筛选出的适宜浓度40 mg L–1Al3+处理52份豌豆品种(系)种子,结果显示,萌发期8个相关性状在处理组及对照组品种间均存在显著差异,遗传多样性指数分别介于1.43～2.03和1.51～2.06之间。基于AC值聚类分析, 52份豌豆种质可被分为3个耐性级别,其中,第I级含2份,为耐铝毒品种(系);第II级含19份,为敏感品种(系);第III级含31份,为铝毒极敏感性品种(系)。利用豌豆种子发芽率、发芽势、发芽指数、芽长、根长、芽干重、根干重7项指标,结合最优回归方程可初步鉴定豌豆萌发期耐铝毒特性。通过综合评价和聚类分析,筛选出萌发期铝毒耐性极强的种质C175和C145,可作为豌豆铝毒耐性育种和耐性机制研究的重要资源。     

陆地棉抗旱性与SSR分子标记的关联分析

【目的】了解陆地棉抗旱性和寻找与陆地棉抗旱性相关的分子标记,挖掘与抗旱性状相关的优异等位变异。【方法】以191份陆地棉栽培种组成的自然群体为材料,在萌发期采用质量分数为15%的PEG6000竖直滤纸法对191份材料进行胁迫处理,测定其发芽率。根据隶属函数值对萌发期抗旱性划分抗旱级别。利用关联分析的方法以74对SSR引物对该自然群体进行基因组变异扫描。在利用Structure 2.3.4分析该自然群体的遗传结构的基础上,使用Tassel 2.0的GLM模型将基因型数据与萌发期抗旱性状进行关联分析,寻找与抗旱性状相关的分子标记。【结果】筛选出强抗旱材料46份,中等抗旱材料59份,干旱敏感材料86份;群体结构分析将191份材料划分为2个亚群,分别包含123份和68份材料;通过关联分析获得与陆地棉萌发期抗旱性显著相关的分子标记15个,各位点对表型变异解释率为2.2%~7.49%。【结论】本研究筛选出强抗旱材料46份,获得与萌发期抗旱性相关的分子标记15个,可供棉花抗旱标记辅助选择育种利用。     

棉花苗期钾营养效率的基因型分类及钾营养特性差异分析

采用营养钵砂培法,将相对生物量及与之存在显著或极显著相关的6个养分相关辅助指标作为棉花苗期钾营养效率差异评价指标。并基于上述指标,利用SAS软件对38个品种(系)的钾营养效率进行聚类分析,最后综合归纳,将其划分为4种钾效率类型,分别为耐低钾型、较耐低钾型、中间型及低钾敏感型,各包括3个、4个、26个及5个品种,总体呈现出中间多两头少的正态型分布,表明这些指标能较好地反映各品种间钾营养效率的差异。此外,对两极端钾效率类型间的营养特性进行了差异比较与分析,结果表明耐低钾基因型的相对生物量高,具有在低钾下对钾素吸收积累能力强和利用指数高的特点,且二者缺一不可;而低钾敏感型恰恰相反,表现为低钾下相对生物量低,对钾吸收积累能力差、利用指数低的特点。     

低温胁迫对北疆棉花出苗的影响及适宜播种期的研究

【目的】为了解决新疆北疆地区棉花播种出苗期低温冷害问题,【方法】利用人工气候室,对种子低温胁迫设计不同温度进行播种出苗试验,并结合近20年农业气象观测资料,研究播种至出苗的适宜播种温度指标、积温指标、确定棉花适宜播种期。【结果】试验结果表明：棉花种子的萌芽率、萌芽天数、萌芽长度、萌芽鲜重及出苗率等各项参数随温度呈非线性有规律变化。棉花种子低温胁迫时间越长出苗越滞后,所需的积温较多。北疆地区棉花主栽品种播种出苗下限温度为12℃,需要活动积温在160℃.d以上,≥12℃有效积温在55℃.d以上。【结论】通过人工气候室试验结合大田实际监测研究,新疆北疆地区稳定通过12℃应作为棉花主栽品种播种的初始期；播种期确定在4月下旬,出苗期可免受春季低温冷害的威胁。     

Integrated Evaluation and the Physiological and Biochemical Responses of Semi-Wild Cotton under Complex Salt-Alkali Stress

[Objective] The genetic diversity of semi-wild cotton was abundant, so more new elite resistant genes could be found and applied to improve the resistance of cotton. The aim of this study was to primarily study on the regulation of response to salt-alkali stress, explore the method of integrated evaluation and characterize the resistance of semi-wild cotton. [Method] Four semi-wild and two cultivated Gossypium hirsutum accessions were evaluated for phonotypical, physiological and biochemical traits under alkali-salt versus normal conditions in hydroponic solutions. The alkali-salt tolerance was determined based on principal component analysis, cluster analysis, correlation analysis, grey rational analysis and analysis of variance. [Result] On the basis of the overall results, the alkali-salt stress tolerance of the six accessions was ranked as: Marie-galante85 > Latifolium32 > CRI16 > CRI12 > Latifolium40 > Latifolium130. Roots were found to be the most important responsive systems to complex alkali-salt stress. At seedling growth stage, the active scavenging system played a crucial role in response to alkali-salt stress. In addition, the salt tolerant and salt sensitive accessions showed different response tends towards leaf peroxidase, root ascorbate peroxidase and root catalase within 48 h, suggesting the accessions have different levels of response to salt stress. [Conclusion]Our study identified the most alkali-salt tolerant accessions and provided basic concept of complex alkali-salt tolerance mechanism within cotton accessions. And, our study provided a simple and rapid, highly accurate and precise method for evaluating salt resistance of cotton, and proved that the balance of ROS system play an important role in response to salt-alkali stress. Hence, mining of salt tolerant genes from these accessions may facilitate the development of novel salt tolerant variety.     

种子沙引发对转基因抗虫棉耐盐性的影响

 以转基因抗虫棉花品种中棉所41和浙905为材料,以其遗传背景品种中棉所23为对照,研究了种子沙引发处理对转基因抗虫棉品种在0%、1.0%和1.5% NaCl浓度下的萌发率、出土率和幼苗生长特性的影响。结果表明,沙引发处理对转基因抗虫棉品种在盐胁迫下的种子萌发和幼苗生长具有明显的效果,但对于非转基因棉品种的效果不明显。幼苗子叶、茎秆和根的超氧化物歧化酶（SOD）活性、过氧化物酶（POD）活性和丙二醛（MDA）含量测定结果表明,沙引发处理使棉花幼苗的子叶和根部维持了较高的SOD与POD活性,但显著减少幼苗体内MDA的积累,说明沙引发有助于促进棉花在逆境下幼苗生长发育和抗逆性的提高。     

绿豆种质资源苗期抗旱性鉴定

鉴定筛选苗期抗旱绿豆种质,对改良绿豆品种抗旱性、促进绿豆产业发展具有重要意义,同时,也为"绿豆抗旱性鉴定评价技术规范"的制定提供方法和信息支撑。本研究以70份绿豆种质为材料,采用苗期反复干旱法,测定幼苗存活率、萎蔫指数、株高、叶片鲜重、叶片干重、叶片含水量、生物量和胁迫指数等指标,分析各指标间的相关性,结果显示第1次旱胁迫后的幼苗存活率与第2次旱胁迫后的幼苗存活率呈极显著正相关;萎蔫指数、株高与幼苗存活率呈极显著负相关,故遴选出第1次旱胁迫幼苗存活率、萎蔫指数和株高为绿豆苗期抗旱性评价的适宜指标。采用隶属函数法,综合分析划级,获得高抗旱种质16份、抗旱种质20份,中抗种质23份、敏感种质8份和极敏感种质3份。以第1次旱胁迫幼苗存活率、萎蔫指数和胁迫株高分别评价绿豆的抗旱性并与综合评价结果相比较,一致率分别为70.0%、58.6%和51.4%。认为第1次旱胁迫幼苗存活率可以作为大规模绿豆种质苗期抗旱筛选的鉴定指标。     

大豆农家品种资源芽期耐盐性鉴定及耐盐品种筛选

栽培大豆属于中度耐盐植物,盐胁迫导致其正常的生长发育进程受到抑制。本研究测定了NaCl处理下,18份大豆农家品种资源的发芽率、发芽势、株高、胚轴长、根长、侧根数、干物质积累等指标。明确了NaCl胁迫条件下,发芽率、发芽势、株高、胚轴长、根长、侧根数、干物质积累等指标均呈降低趋势。筛选出耐盐品种G08,盐害指数18.00%。证明了发芽势、发芽率、株高、胚轴长、根长与品种间耐盐性呈显著相关关系,能更好的反应大豆的耐盐性。为大豆耐盐种质创制提供丰富的数据参考和亲本材料,为完善大豆种质资源耐盐性研究和提高盐渍土壤利用效率提供资料依据。