多胺对玉米种子吸胀期间耐冷性和种子发芽能力的影响

以玉米耐寒自交系黄C和低温敏感自交系Mo17为材料, 研究了亚精胺(Spd)和精胺(Spm)引发对玉米种子吸胀中的耐冷性和种子发芽能力的影响。种子经0.25 mmol L^-1的Spd和Spm引发72 h后, 在5℃下低温吸胀不同时间(12、24、36和48 h)。结果表明, Spd和Spm引发提高了胁迫期间两自交系胚内过氧化物酶(POD)、过氧化氢酶(CAT)、超氧化物歧化酶(SOD)和抗坏血酸过氧化物酶(APX)活性, 以及可溶性蛋白质和脯氨酸(Pro)含量, 降低了胚渗出液的核苷酸含量, 同时显著提高发芽率, 并显著缩短平均发芽时间。低温吸胀48 h后, 与对照相比, Spd和Spm处理分别提高两自交系种子的平均发芽率18.5%和14.0%, 分别缩短平均发芽时间1.21 d和1.14 d。黄C在种子吸胀期间的耐冷性强于Mo17。总之, Spd和Spm处理能提高玉米种子吸胀期间的耐冷性, 提高低温胁迫下种子发芽能力。     

外源施加多胺对提高玉米种子耐冷性的研究

以玉米耐冷自交系辽2386和冷敏感自交系辽6082为材料,研究了以外源施加精胺(Spm)和亚精胺(Spd)作为引发剂,对玉米种子吸胀中的耐冷性、发芽能力和苗期生物量的影响,探讨利用外源多胺缓解玉米低温胁迫的相关机制。结果表明,种子经Spd和Spm引发低温(5℃)吸胀后,辽6082发芽率为93%,和引发前相比显著提高了12%,且苗高显著提高了44.62%,苗鲜重显著增加了26.76%。同时,Spd和Spm引发提高了低温胁迫期间两自交系胚中超氧化物歧化酶(SOD)和过氧化物酶(POD)的活性,降低了丙二醛(MDA)的含量。自交系辽2386在种子吸胀期间的耐冷性强于辽6082,而不同自交系、不同器官对多胺敏感性不同。总之,Spd和Spm处理能提高玉米种子吸胀期间的耐冷性,提高低温胁迫下种子的抗氧化能力和发芽能力。     

外源抗坏血酸对棉花种子萌发耐冷性的影响

为探讨外源抗坏血酸(ExAsA)对棉花种子萌发耐冷性的影响,以新疆北疆棉区主栽陆地棉品种新陆早61号为材料,通过配置不同处理浓度(0,25,50,100,200 mg/L)和时间(3,6,12,24 h)的引发组合,研究ExAsA对低温(15℃)胁迫下棉花种子萌发特性的影响。结果表明:ExAsA可以提高棉花种子在低温下的发芽率,增加发芽势,缩短种子平均发芽时间。最适引发处理浓度为50 mg/L,最适引发处理时间为24 h。与对照(ck)相比,最佳ExAsA引发组合(50 mg/L,24 h)处理的种子在低温下的种子发芽势、发芽率、发芽指数、种子萌发指数分别提高了24.45%、30.00%、11.89、0.53,平均发芽时间缩短了1.39 d,且各项种子萌发指标较对照在0.01显著水平上均差异极显著。     

H2O2对黄瓜种子发芽及幼苗抗冷性的影响

以津春四号黄瓜种子为试材,用不同浓度的H2O2溶液对黄瓜种子进行浸种处理,研究其对黄瓜种子发芽及幼苗对低温胁迫的影响.研究结果表明:适宜浓度的H2O2溶液能显著提高黄瓜种子发芽率,提高黄瓜幼苗在低温胁迫后叶片内叶绿素的含量,提高脯氨酸、过氧化氢酶的含量,降低丙二醛的含量,从而提高幼苗的抗冷性.     

低温胁迫对菜豆种子吸胀期间生理特性和发芽能力的影响

为探讨菜豆种子在低温胁迫下吸胀期间的生理及发芽能力。以12个菜豆品种的种子为试验材料,设置常温对照(CK)和4℃低温(LT),测定低温胁迫对菜豆种子吸胀期间的生理特性和发芽能力的影响。结果表明：与常温对照相比,低温处理的12种菜豆的发芽率均有所降低,根系活力在不同的品种中表现不同,超氧化物歧化酶(SOD)活性大部分降低,过氧化氢酶(CAT)活性降低,过氧化物酶(POD)活性在4个品种中显著升高;丙二醛(MDA)和可溶性蛋白含量在不同的品种变化不同,但两者之间呈正相关关系;电解质渗漏率在4个品种中增高。不同菜豆品种的种子对吸涨冷害的响应模式存在很多大的差异,解析高抗型和敏感型菜豆种子响应吸胀冷害的生理生化变化,可为进一步筛选抗吸胀冷害的菜豆品种提供理论基础。     

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。     

PEG浸种处理提高烟草种子活力的效应

用PEG浸种处理烟草种子,研究了不同浓度和处理时间组合对烟草种子活力的影响。结果表明,PEG处理能显著提高种子发芽率和幼苗活力指数,增强种子萌发时的呼吸速率和淀粉酶活性.且以20％PEG-6000浸种48h的效果最好。不同活力水平的种子经20%PEG处理后,幼苗活力指数明显提高,处理组的超氧物歧化酶(SOD)、过氧化氢酶(CAT)和过氧化物酶(POD)活性升高,膜脂过氧化产物丙二醛(MDA)含量和超氧阴离子(O2-)产生速率及电解质渗漏率显著低于对照组。研究还发现,PEG处理能减少低温吸胀期间种子内电解质渗漏量及渗漏速率,并提高种子在低温下的萌发率,增强幼苗抗冷性。     

不同细胞活性物质对低温下通草种子及幼苗的影响

通草是贵州一种道地中药材，播种育苗时常会遇到春季低温的影响，导致其发芽率较低。本研究采用不同浓度的不同细胞活性物质硝普钠(SNP)、海藻糖(TH)和赤霉素(GA₃)进行种子引发，研究在常温和低温胁迫下不同细胞活性物质不同浓度处理对通草种子萌发及幼苗生长的影响。结果表明，适合浓度的SNP引发可显著改善通草种子在低温胁迫下的发芽势、发芽率、发芽指数，缩短发芽时间，增加幼苗的根长、苗高和干鲜重，其中以200μmol/L SNP引发的效果最好，而其他处理的效果不佳，表明适合浓度的SNP引发可提高通草种子及幼苗对低温的耐受性。     

杂草稻种子芽期对盐碱胁迫的响应

盐碱胁迫对未吸胀种子发芽率、发芽势、芽长和主根长伤害率大于吸胀种子.WR 03-12的吸胀种子在各浓度盐碱胁迫下发芽率和发芽势受影响较小,未吸胀种子发芽率和发芽势只在高中性盐和高碱性盐处理下与对照相比达显著差异.无论是吸胀种子还是未吸胀种子,WR 03-12发芽率及发芽势相对伤害率均小于其他两个材料.     

低温发芽鉴定茄子耐冷性的研究

本文通过低温发芽鉴定了不同茄子品系（品种）耐冷性。从中确定了18℃是研究茄子耐冷性的适宜温度，并进一步研究了3个茄子品系的种子（品种）在18℃低温处理下的发芽情况，研究得出：发芽指数和综合隶属含数值能较好地反映茄子耐冷性的大小，最后对茄子幼苗进行了生理测定，并得出细胞膜透性与种子发芽的综合隶属含数值呈显著正相关。     

H2O2对吸胀冷害下花生种子萌发的影响

为探明H₂O₂浸种对吸胀冷害下花生种子萌发和生理代谢的影响,选择豫花9326和豫花37为材料,用50mmol/L H₂O₂进行低温（5℃）浸种,以灭菌水低温浸种为对照,进行发芽试验。结果表明,与对照相比,处理后豫花9326的发芽势、发芽率和发芽指数分别提高了31.25%、18.52%、50.53%,豫花37分别提高了14.58%、3.64%、36.13%,种子电导率分别显著降低了47.67%和23.67%,其中豫花9326发芽相关指标增长比例高于豫花37。与对照相比,用H₂O₂处理的豫花9326在萌发的第0、4、6天丙二醛含量分别降低了0.22%、7.05%和32.55%,可溶性糖含量分别显著提高了48.27%、53.42%和52.29%,可溶性蛋白含量分别显著增加了59.66%、13.04%和43.76%,脱落酸（ABA）含量呈先降低后升高的变化趋势,赤霉素（GA）含量和GA/ABA比值均呈显著增长的趋势。H₂O₂浸种可能是通过维持种子细胞膜的完整性、增加可溶性物质含量以及调控内源激素含量,来提高花生种子对吸胀冷害的抗性,从而提高发芽率、发芽势和发芽指数。本研究可为花生萌芽期耐寒性的调控技术提供方法和理论依据。     

Effects of the Seed Film Coating Salicylic Acid on the Chilling Tolerance of Cotton Seedlings

The objective of this study was to investigate the effect of the different concentrations of the seed film coating salicylic acid on the cold tolerance of cotton seedlings using the sand culture method. The physiological response of cell membrane permeability, protective enzyme activity and osmotic adjustment of cotton seedling were measured before and after at low temperature stress and at normal temperature. The results showed that 1-10 mmol·L^－1 of seed film coating with salicylic acid seed coating treatment could effectively alleviate damage to cotton seedlings at low temperature, and the accumulation of the relative electrical conductivity and malondialdehyde were reduced on cotton seedlings. The activity of superoxide dismutase, peroxidase, catalase, and soluble protein, soluble sugar and proline contents increased sharply. These results indicate that film coating with salicylic acid can alleviate the effects of low temperature stress on seedling growth inhibition and improve the cotton seedlings by providing chilling tolerance, and the optimum treatment concentration salicylic acid is 5 mmol·L^－1.     

低温胁迫对燕麦种子萌发期蛋白质组影响的研究

为探析燕麦种子萌发时蛋白质的差异表达及其相关蛋白的生理功能,采用室内生测法比较了不同温度下种子萌发力和幼苗的生长能力,同时采用双向电泳(2-DE)结合基质辅助激光解析飞行时间质谱的方法,比较低温条件下(5℃)吸胀25 h和128 h(萌发)与正常温度下吸胀25 h(萌发)时种子蛋白质组的差异表达.结果表明,随着温度的降低,燕麦种子的萌发活力降低.燕麦种子蛋白质组在低温胁迫下萌发时,有7个蛋白质点发生了变化,其中5℃低温吸胀25h时,有3个蛋白质点的表达量降低;5℃低温吸胀萌发128h时,有5个蛋白质点表达发生了改变,其中3个蛋白质点的表达量增加.经MALDI-TOF质谱鉴定分析和Mascot搜索NCBI非冗余数据库,确定了4个蛋白质,分别为燕麦蛋白、燕麦蛋白N9和丝氨酸蛋白酶抑制剂等.这些蛋白质的质量变化与燕麦种子萌发时的低温胁迫可能有关联.     

Effects of Melatonin on the Antioxidant Enzyme Activities and Seed Germination of Cotton (Gossypium hirsutum L.) under Salt-Stress Conditions

[Objective] Cotton (Gossypium hirsutum L.) seed germination, in which melatonin plays an important regulatory role, is seriously affected by soil salinization. Cotton seed germination, antioxidant enzyme activity levels and other physiological indicators were analyzed to clarify the regulatory effects of exogenous melatonin on cotton seed germination under salt-stress conditions. [Method] The experiment was conducted in a greenhouse of Hebei Agricultural University in Baoding City, Hebei Province from 2018 to 2019 using Guoxin Cotton 9 as the material. The germination rate, germination potential, seed biomass after germination, superoxide dismutase (SOD), peroxidase (POD) and catalase (CAT) activities, as well as the malondialdehyde (MDA) content, of cotton seeds were measured after exposure to different melatonin concentrations (0, 10, 20, 50 and 100 μmol·L^－1) and 150 mmol·L^－1 NaCl treatments. [Result] After germination, the germination rate, germination potential, radical length and seed biomass significantly decreased, as did the SOD, POD and CAT activities. However, the MDA content significantly increased under salt-stress conditions. Low exogenous melatonin concentrations (10 and 20 μmol·L^－1) increased the germination potential, germination rate and biomass of cotton seeds, and promoted the elongation of radicals; however high melatonin concentrations (50 and 100 μmol·L^－1) inhibited cotton seed germination and decreased seed biomass after germination. Low melatonin concentrations (10 and 20 μmol·L^－1) increased the SOD, POD and CAT activities and decreased the MDA content in cotton seeds. [Conclusion] Low melatonin concentrations could promote germination and improve the salt tolerance of cotton seeds, while high melatonin concentrations could inhibit their germination. A 20 μmol·L^－1 melatonin concentration is appropriate for regulating cotton seed germination under salt-stress conditions.     

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。     

外源褪黑素对低温胁迫下菜豆种子萌发及抗性的影响

为了探究褪黑素(Mt)对低温环境下菜豆种子的影响,本研究对菜豆种子进行低温处理(LT)和低温加褪黑素的处理(LT+Mt),并设置常温处理作为对照(CK),对同时期的各项生理指标进行测定。结果表明：Mt可以提高低温胁迫下的种子萌发率,但萌发率要低于对照;同时对渗透调节物质、O₂^-和MDA、抗氧化酶活性进行测定,发现低温增加了渗透调节物质的含量,当加入Mt后其含量进一步增加;低温处理后O₂^-和MDA的含量增加,当加入Mt后其含量明显降低,但是要高于对照;低温处理后抗氧化酶活性略低于对照,当加入Mt后其含量显著升高。研究表明外源Mt有效的减轻了低温对种子萌发的损害,从而促进种子萌发过程中抵御低温的能力。     

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   

Evaluation of cassava (Manihot esculenta Crantz) germplasm collections using RAPD markers

Summary Deterioration of cotton, Gossypium hirsutum L., seed can adversely affect stands, seedling vigor, and subsequent performance of plants, but deterioration can be lessened by improved genetic resistance. This study was conducted to evaluate the relationship of physical and germination characteristics of cotton seed and to determine the inheritance of resistance to seed deterioration. Physical (weight, volume, density, and imbibition rate) and germination (germination of non-deteriorated seed and deteriorated seed) characteristics were determined for eight cotton genotypes. In addition, imbibition rate and the germination characteristics were determined for all possible F₁, including reciprocals, combinations of the eight genotypes. Variation among the parents for germination of deteriorated seed and imbibition rate were significantly, highly correlated (r=–0.97) and intrinsically related. Resistance to seed deterioration tended to increase as seed weight and volume decreased. Significant genetic effects were found for imbibition rate and germination of both non-deteriorated and deteriorated seed. However, general combining ability (GCA) accounted for only 21% of the variation in crosses sums of squares for germination of non-deteriorated seed. In contrast, GCA accounted for 90% of the variation for germination of deteriorated seed and imbibition rate. A breeding approach involving selection of early generation seed for ability to survive hot water treatment, then evaluating later generations for imbibition rate is suggested as a means to improve resistance to seed deterioration in cotton.