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1.
不同生态环境下野生大豆根解剖结构演化研究 总被引：1，自引：0，他引：1
以不同生态环境下的野生大豆,即:野生大豆2013-001-01(盐生环境)和野生大豆2013-001-02(中生环境)为试材,基于结构植物学角度,应用石蜡切片和光学显微技术对供试的野生大豆根解剖结构进行比较研究,旨在为我国大豆属植物颉颃盐逆境研究提供解剖学依据。结果表明:2013-001-02根的维管柱为五原型,2013-001-01根的维管柱已经演化为四原型,相对于2013-001-02,2013-001-01根的皮层较完整,韧皮纤维发达且形成"韧皮屏障",次生木质部导管数量较多且存在侵填体,导管的傍管薄壁细胞较大且数量较多,射线径向长度相对较短。研究证明:野生大豆2013-001-01植物的根已经演化出颉颃盐逆境解剖结构。 相似文献
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为揭示根系在褪黑素缓解植物镉胁迫效应中的作用,利用水培实验探讨了外源褪黑素对不同浓度镉处理(0、2、10 mg·kg-1)下紫苏(Perilla frutescens)生长、根系形态及解剖结构、镉及相关必需元素含量等的影响。结果显示:镉处理显著抑制了紫苏地上部生长,未造成紫苏根系生物量显著改变,但根系形态和解剖结构发生显著变化,长度变短、直径变粗、表面积减小、中柱变粗、皮层占横切面的比例降低;低浓度镉处理的紫苏在添加外源褪黑素后,地上部生物量显著提高,根系镉含量和累积量、镉转运系数以及地上部镉含量和累积量显著下降,同时根系长度变长、中柱变细、皮层占比增加,根系中锌和铁的含量显著增加;高浓度镉处理的紫苏在添加外源褪黑素后,镉转运系数和地上部累积量显著降低,根系中锌含量显著增加,但地上部生物量没有增加。研究表明,外源褪黑素可以通过改变紫苏根系形态和解剖结构,同时增加锌和铁元素吸收,降低根系对镉的吸收以及向地上部位的转运,进而缓解镉胁迫对紫苏生长的抑制作用,但缓解作用因紫苏受镉胁迫程度不同而有所差异。 相似文献
3.
缺氮复氮处理对玉米根系生长、根系活力、硝态氮及氨基酸含量的影响 总被引：2，自引：0，他引：2
为明确缺氮复氮处理对根系生长、根系活力、硝态氮含量及氨基酸含量的影响,对水培玉米幼苗进行研究。结果表明,缺氮处理的根系总长、根表面积、分根数比正常处理的较大,复氮处理后各测定指标均有一定恢复;缺氮处理根系活力显著下降,降幅达50.91%,复氮处理后根系活力有所恢复,但仍然降低42.15%;缺氮根系的NO3- N含量比正常处理降低76.21%,复氮处理后NO3- N含量仍然降低40.97%;缺氮根系的天冬氨酸、苏氨酸、丝氨酸、谷氨酸、脯氨酸、甘氨酸和丙氨酸的含量明显下降,复氮处理后这些氨基酸含量仍然低于正常处理。 相似文献
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Root C and root-released C are closely related to soil organic matter content and mechanistic simulation modeling has proven to be useful for studying root and soil organic C dynamics in plant-soil ecosystems.A computer model was designed in this study to simulate the dynamics of root C and root released C decomposition in situ and the dynamics of different forms of C in soil under two barley cultivars(Abee and Samson).The results showed that on the 15th day,about 48%of the total 14C fixed in roots was respired for Abee and 42%for Samson.This indicated that the turnover rate of root 14C of Abee was higher than that of Samson.The percentage of water-soluble organic 14C,active microbial 14C and stable 14C over the total fixed 14C were not different between two barley cultivars.From the analysis of the model for two barley cultivars,the total 14C transformed into different soil pools(excluding CO2-C and root C pools)for the two barley cultivars was similar(26%for Abee and 25%for Samson),but the difference of 14C remaining in soil between the two barley cultivars was mainly because of the difference of 14C remaining in roots which have not been yet decomposed.Some of the information which could not be measured in the laboratory conditions was obtained in this study. 相似文献
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干旱胁迫对不同抗旱性苜蓿品种根系生长及生理特性影响 总被引：11，自引：2，他引：11
【目的】研究干旱胁迫对不同抗旱性苜蓿品种根系生长特征及生理特性的影响,明确不同抗旱性苜蓿品种响应干旱胁迫的生长及生理差异,为进一步阐明紫花苜蓿抗旱的分子机理、提高紫花苜蓿耐旱性和水分利用效率提供理论依据。【方法】采用营养液沙培法,选用强抗旱的陇中苜蓿（Medicago sativa L. cv. Longzhong）、中抗旱的陇东苜蓿（Medicago sativa L. cv. Longdong）和弱抗旱的甘农3号紫花苜蓿（Medicago sativa L. cv. Gannong No.3）为试验材料,在幼苗期对其进行6种不同水势（0、-0.4、-0.8、-1.2、-1.6和-2.0 MPa）的PEG-6000人工模拟干旱胁迫,研究干旱胁迫对供试苜蓿根系生长特征（根系总长度、根系总表面积、根系平均直径、根体积、根尖数和根系干重）、根系活力、游离脯氨酸（Pro）含量、可溶性蛋白（SP）含量、可溶性糖（SS）含量,丙二醛（MDA）含量、质膜相对透性、活性氧（H2O2、OH·和O2•-）含量,抗氧化酶（SOD、POD和CAT）活性、还原型抗坏血酸（AsA）和还原型谷胱甘肽（GSH）含量的影响。并用逐步回归分析建立最优回归方程,进而筛选出不同胁迫程度下对不同抗旱性苜蓿品种抗旱性影响较为显著的指标。【结果】干旱胁迫会显著影响苜蓿的根系生长特征及生理特性。随着干旱胁迫的加剧,供试苜蓿的根系总长度、Pro含量、MDA含量、质膜相对透性、活性氧（H2O2、OH·和O2•-）含量及CAT活性不断增加;根系干重、根系活力、SS含量和GSH含量先增加后下降。此外,随胁迫程度增加,陇中苜蓿的根系平均直径、根体积、根尖数、POD活性及SOD活性均呈先增加后下降的变化趋势,AsA含量不断增加;陇东苜蓿和甘农3号的根系平均直径、根体积、根尖数、POD活性及根系总表面积则呈不断下降的趋势,而AsA含量呈先增加后下降的变化趋势。整体而言,陇中苜蓿的根系总长度、根系总表面积、根系干重显著高于陇东苜蓿和甘农3号,H2O2含量和O2•-含量显著低于甘农3号;陇中苜蓿和陇东苜蓿的SP含量、SS含量和MDA含量显著低于甘农3号。-1.2 MPa至-2.0 MPa胁迫时,陇中苜蓿的H2O2和OH·含量显著低于陇东苜蓿。-2.0 MPa胁迫时,陇中苜蓿的POD活性、AsA和GSH含量均显著高于甘农3号。逐步回归分析表明,根系活力、根体积、根系总长度、MDA和AsA是对陇中苜蓿抗旱性影响较为显著的指标;根尖数、根系平均直径、根系总表面积、根系干重、O2•-、GSH和CAT是对陇东苜蓿抗旱性影响较为显著的指标;根系活力、根尖数、Pro、SS、MDA、质膜相对透性和GSH是对甘农3号紫花苜蓿抗旱性影响较为显著的指标。【结论】不同抗旱性苜蓿品种在形态特征和生理特性上对干旱胁迫存在相同和不同的生长及生理响应策略。轻度和中度胁迫（0 MPa至-1.2 MPa）下,抗旱苜蓿品种主要通过增加根系总长度、根体积和根尖数及降低膜脂过氧化程度来适应干旱,弱抗旱苜蓿品种则通过改变细胞膜稳定性、根系活力及渗透调节能力来适应干旱;重度胁迫（-1.2 MPa至-2.0 MPa）下,不同抗旱性苜蓿品种均可通过改变根系生长特征和启动抗氧化系统来抵御干旱,其中强抗旱苜蓿品种主要通过增加根长和AsA含量来适应干旱,而中等抗旱和弱抗旱苜蓿品种主要通过增加根尖数和GSH含量来适应干旱。 相似文献
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Ling-shuang WANG Qing-shan CHEN Da-wei XIN Zhao-ming QI Chao ZHANG Si-nan LI Yang-mei JIN Mo LI Hong-yao MEI An-yu SU Xiao-xia WU 《农业科学学报》2018,17(9):1959-1971
Glycogen synthase kinase 3 (GSK3) is a kind of serine/threonine kinase widely found in eukaryotes. Many plant GSK3 kinases play important roles in regulating stress responses. This study investigated BRASSINOSTEROID-INSENSITIVE 2 (GmBIN2) gene, a member of the GSK3 protein kinase family in soybean and an orthologue of Arabidopsis BIN2/AtSK21. GmBIN2 expression was increased by salt and drought stresses, but was not significantly affected by the ABA treatment. To examine the function of GmBIN2, transgenic Arabidopsis and transgenic soybean hairy roots were generated. Overexpression of GmBIN2 in Arabidopsis resulted in increased germination rate and root length compared with wild-type plants under salt and mannitol treatments. Overexpression of GmBIN2 increased cellular Ca2+ content and reduced Na+ content, enhancing salt tolerance in transgenic Arabidopsis plants. In the soybean hairy root assay, overexpression of GmBIN2 in transgenic roots also showed significantly higher relative root growth rate than the control when subjected to salt and mannitol treatments. Measurement of physiological indicators, including proline content, superoxide dismutase (SOD) activity, and relative electrical conductivity, supported this conclusion. Furthermore, we also found that GmBIN2 could up-regulate the expression of some stress-related genes in transgenic Arabidopsis and soybean hairy roots. Overall, these results indicated that GmBIN2 improved tolerance to salt and drought in transgenic Arabidopsis and soybean hairy roots. 相似文献
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【目的】水稻栽培区土壤的盐、碱化日趋严重,植物体内Na+、K+浓度及Na+/K+是植物耐盐、碱性重要指标。在盐、碱胁迫条件下检测水稻苗期地上部和根部的Na+、K+浓度及Na+/K+的QTL位点,为水稻的耐盐、碱性遗传机制及分子标记辅助育种提供理论依据。【方法】以优质高产水稻品种东农425与耐盐、碱水稻品种长白10为亲本构建重组自交系(RIL)为作图群体,利用102对SSR标记构建遗传连锁图谱,该图谱覆盖水稻基因组约1 915.05 c M,标记间平均距离为18.77 c M;在140 mmol·L-1 Na Cl盐胁迫和0.15%Na2CO3碱胁迫处理条件下,对水稻苗期地上部和根部的Na+、K+浓度及Na+/K+等性状进行测定,利用SPSS v19.0对各性状进行相关分析,并采用QTL Ici Mapping v3.3的完备区间作图法(ICIM)进行QTL定位。【结果】盐、碱胁迫条件下,亲本及RIL群体地上部Na+、K+浓度均高于地下部Na+、K+浓度,各性状在RIL群体中基本符合正态分布,表现出典型的数量性状遗传特征,符合QTL定位要求。相关分析结果表明,盐、碱胁迫条件下,地上部Na+与K+及根部Na+与K+均呈极显著正相关,2种胁迫条件下的各性状相关性不显著。盐、碱胁迫条件下共检测到15个与Na+、K+浓度和Na+/K+相关的QTL,2种条件下所检测到的QTL位于不同染色体区域。在盐胁迫下共检测到5个QTL,包括1个与地上部K+浓度相关QTL,位于第8染色体的RM1308—RM281区间内,贡献率为6.83%;3个与根部Na+浓度相关QTL,位于第3和第8染色体上,其中q SRNC3-1贡献率最大,为16.41%;1个与根部K+浓度相关QTL,贡献率为3.52%;未检测到与地上部Na+浓度、Na+/K+及根部Na+/K+相关的QTL。在碱胁迫下共检测到10个QTL,包括1个与地上部Na+浓度相关的QTL,位于第2染色体的RM1347—RM48区间内,贡献率为14.41%;1个与地上部K+浓度相关QTL,位于第2染色体的RM1255—RM213区间内;3个与地上部Na+/K+相关QTL,分别位于第2、7、10染色体上,其中q ASNK2贡献率最大,为7.57%;1个与根部Na+浓度相关QTL,位于第3染色体的RM293—RM232区间内,贡献率为13.71%;2个与根部K+含量相关QTL,分别位于第1染色体的RM5—RM9和第2染色体的RM12865—RM12941区间内;2个与根部Na+/K+相关QTL,分别位于在第3和第4染色体上,其中q ARNK3贡献率较大,为10.48%。通过比较图谱发现,本研究中的大部分QTL与以往不同群体中影响耐盐、碱相关性状的QTL定位在同一或相邻的染色体区域,另外在碱胁迫下所检测到的q ASKC2和q ARKC2在前人研究中未见报道,可能存在新的耐碱性位点。【结论】在盐、碱胁迫条件下,Na+、K+的吸收和运输均是平行而独立的过程,且根部对Na+和K+的吸收与向地上部运输存在不同的遗传机制;盐、碱胁迫条件下,水稻Na+、K+浓度的遗传是相互独立的。 相似文献
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根际促生细菌的挥发性有机化合物（VOCs）可以促进植物生长并提高植物对盐、旱和病菌的抵抗力。分析了芽孢杆菌PDR1产生的VOCs对拟南芥耐碱胁迫能力的影响及其生理机制。在芽孢杆菌PDR1存在或不存在的条件下,对拟南芥进行培养;检测对照和碱胁迫条件下拟南芥根部的各种离子含量;用pH指示剂（溴甲酚紫）和pH计检测拟南芥的根际酸化能力;检测拟南芥根部质膜H+-ATPase活性。结果显示,芽孢杆菌PDR1的VOCs改善了同一空间中碱胁迫下拟南芥的根长和根部离子平衡;来自芽孢杆菌PDR1的VOCs增强了拟南芥根中质膜H+-ATPase的活性,并提高了拟南芥植物的根际酸化能力。研究结果将促进对芽孢杆菌调节拟南芥生长和抗逆性机制的理解,并为其在农业生产和生态保护中的广泛应用奠定基础。 相似文献
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为研究曼陀罗对重金属镉的耐性机制，以前期筛选的曼陀罗（Datura stramonium L.）为试验材料，通过水培方式探究镉（Cd）胁迫下曼陀罗对Cd的吸收累积特性及其在植株体内的亚细胞分布特征。结果表明：介质中Cd无论低浓度还是高浓度，曼陀罗各部位的Cd含量都表现为根 > 茎 > 叶，但迁移系数差异不显著。曼陀罗根系Cd2+流速在不同位置具有显著差异，其中分生区和伸长区的Cd2+流速显著大于根冠区和成熟区。当介质中Cd浓度由0.1 mg·L-1增至2.5 mg·L-1时，细胞壁和细胞液中Cd含量之和所占比例显著增大。研究表明，曼陀罗根系对Cd2+的吸收主要集中在分生区和伸长区，当介质中Cd浓度较低时，根系中细胞壁对Cd向上运输的限制及茎叶中细胞液对Cd的区室化起重要的作用；当Cd浓度较高时，根部细胞各组分中细胞液所占比重增加，Cd由根系向上迁移，此时茎叶中细胞壁对Cd的固定作用增强，其可能是曼陀罗耐受高Cd胁迫的机制之一。 相似文献
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Image-based root phenotyping for field-grown crops: An example under maize/soybean intercropping 
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下载免费PDF全文 HUI Fang XIE Zi-wen LI Hai-gang GUO Yan LI Bao-guo LIU Yun-ling MA Yun-tao 《农业科学学报》2022,21(6):1606-1619
Root architecture, which determines the water and nutrient uptake ability of crops, is highly plastic in response to soil environmental changes and different cultivation patterns. Root phenotyping for field-grown crops, especially topological trait extraction, is rarely performed. In this study, an image-based semi-automatic root phenotyping method for field-grown crops was developed. The method consisted of image acquisition, image denoising and segmentation, trait extraction and data analysis. Five global traits and 40 local traits were extracted with this method. A good consistency in 1st-order lateral root branching was observed between the visually counted values and the values extracted using the developed method, with R2=0.97. Using the method, we found that the interspecific advantages for maize mainly occurred within 5 cm from the root base in the nodal roots of the 5th–7th nodes, and that the obvious inhibition of soybean was mostly reflected within 20 cm from the root base. Our study provides a novel approach with high-throughput and high-accuracy for field research on root morphology and branching features. It could be applied to the 3D reconstruction of field-grown root system architecture to improve the inputs to data-driven models (e.g., OpenSimRoot) that simulate root growth, solute transport and water uptake. 相似文献
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Effects of NaCl and Iso-Osmotic Polyethylene Glycol Stress on Na+/H+ Antiport Activity of Three Malus species with Different Salt Tolerance 下载免费PDF全文
下载免费PDF全文 Salt stress contains osmotic and ionic stress, while iso-osmotic polyethylene glycol (PEG) has only osmotic stress. This study aimed to compare the different effects on the activity of H+-ATPase, proton pump and Na+/H+ antiport in Malus seedlings between osmotic and ionic stress. Species of salt tolerant Malus zumi, middle salt tolerant Malus xiaojinensis and salt sensitive Malus baccata were used as experimental materials. Malus seedlings were treated with NaCl and iso-osmotic PEG stress. The activity of H+-ATPase, proton pump and Na+/H+ antiport of plasmolemma and tonoplast in Malus seedlings were obviously increased under salt stress, and those in salt-tolerant species increased more. Under the same NaCl concentration, the activity of H+-ATPase, proton pump and Na+/H+ antiport of plasmolemma and tonoplast in salt-tolerant species were all obviously higher than those in salt-sensitive one. Higher Na+/H+ antiport activity of plasmolemma and tonoplast in salt-tolerant species could help to extrude and compartmentalize sodium in roots under salt stress. The ascent rate of activity of H+-ATPase, proton pump and Na+/H+ antiport in Malus seedlings under the three salt concentration stress was all obviously higher than that under the iso-osmotic PEG stress. It indicated that the sodium ion effect had more stimulation on the activity of H+-ATPase, proton pump and Na+/H+ antiport in salt-tolerant species, and salt-tolerant species has higher capability of sodium extrusion and compartmentalization in roots and is therefore more salt tolerant. 相似文献
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设置模拟氮沉降的控制试验,以NH4NO3作为外加氮源,设计CK(0kg N hm-2·a-1)、LN(50 kg N hm-2·a-1)、MN(100 kg N hm-2·a-1)、HN(150 kg N hm-2· a-1)4个处理,历时9个月,测定木荷(Schima superba)幼苗的光合特性、生物量和C、N、P含量及其分配格局对氮沉降的响应.结果表明:(1)木荷幼苗的最大净光合速率和光饱和点随着氮处理水平增加呈先增加后减小的特点,在中氮处理下极显著增加(P＜0.01).氮处理降低了幼苗的光补偿点和暗呼吸速率,光补偿点在低氮处理下显著降低(P＜0.05),暗呼吸速率在低中氮处理下极显著降低(P＜0.01),高氮处理下显著降低(P＜0.05).未见氮处理对表观量子效率产生显著影响.(2)氮处理促进了木荷的全株生物量以及各部分生物量的增长.随着氮处理水平的增加,叶重比呈升高的趋势,而根重比和根冠比呈降低的趋势,在高氮处理下叶重比的增加和根重比、根冠比的降低都达到了显著水平(P＜0.05).(3)氮沉降促进各器官N含量的增加,在高氮处理下根和茎中N含量极显著增加(P＜0.01),叶中N含量显著增加(P＜0.05).而各器官C含量随着氮沉降程度的增加呈先增加后降低的趋势,在中氮处理下根和茎中C含量极显著增加(P＜0.01),叶中C含量显著增加(P＜0.05).但各器官P含量变化趋势各不相同,随着氮的增加,根中P含量是呈先增加后降低的趋势,而茎和叶中P含量是呈降低的趋势.氮沉降一定程度上降低了木荷各器官的C/N比值而增加了N/P比值. 相似文献
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以水土保持先锋植物百喜草为试验材料,设置不同Pb浓度的室内模拟胁迫试验,定量测定不同浓度Pb处理下百喜草生长及体内重金属含量,分析百喜草对Pb胁迫的耐性及其富集效果。结果表明:百喜草在土壤Pb浓度2500 mg·kg-1条件下仍可生长;Pb胁迫对百喜草各生长指标均有一定抑制作用,地上部分表现为分蘖能力叶最大伸展苗高,根系表现为根体积根平均直径总根长根表面积;轻度Pb胁迫条件下百喜草根系生物量分配较多,随Pb浓度的增大,生物量分配倾向于地上部分;百喜草对Pb具有一定富集能力,根系和地上部分最高分别为3384.56 mg·kg-1和200.70 mg·kg-1,根系对Pb的富集能力远大于地上部分,表现出较弱的转移能力。 相似文献
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以元谋干热河谷10年生印楝和大叶相思为研究对象,采用分层挖掘法对印楝纯林、大叶相思纯林及印楝×大叶相思混交林根系生物量及其分布特征进行研究.结果表明:印楝×大叶相思混交林根系总生物量为2.707 t/hm2,介于印楝纯林(2.264t/hm2)和大叶相思纯林(3.405 t/hm2)之间.混交林内主根总生物量为1.057 t/hm2,为印楝纯林和大叶相思纯林的69.9％和69.7％,而除粗根外,混交林内其它径级的侧根(中根、小根和细根)生物量均介于印楝纯林和大叶相思纯林之间,分别为印楝纯林的228.7％、120.1％、450.0％,为大叶相思纯林的71.3％、65.8％和48.8％.干热河谷印楝和大叶相思人工林根系在土壤表层分布比例大,尤其足0-0.2 m土层内,其根系生物量占根系总生物量的63.6％-76.3％.根系垂直累积生物量与土壤深度可用二次方程拟合,拟合方程的二阶导数表明,垂直方向上,印楝纯林根系分布较混交林均匀,而混交林较大叶相思纯林均匀. 相似文献
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外源褪黑素对干旱胁迫下番茄叶片光合作用的影响 总被引：1，自引：0，他引：1
【目的】褪黑素是一种广泛存在于高等植物体内的小分子物质,被认为是一种新的植物生长调节剂和生物刺激剂,对于提高植物抗逆性具有重要作用。探索外源褪黑素对干旱胁迫下番茄叶片光合作用的影响,为揭示褪黑素调节植物抗逆性的机制打下基础。【方法】以番茄‘辽园多丽’为试材,首先采用叶片喷施和根施不同浓度褪黑素进行预处理:CK:叶片喷施清水、根施50 m L清水;R5、R50、R100、R150、R250:叶片喷清水,分别根施50m L 5、50、100、150和250μmol·L~(-1)褪黑素;L5、L50、L100、L150、L250:根施50 m L清水,叶片分别喷施5、50、100、150和250μmol·L~(-1)褪黑素;连续处理3 d后将植株移至温室中,以不浇水作为干旱处理(其中CK0:叶片喷施清水、根施50 m L清水预处理后正常浇水,CK1:叶片喷施清水、根施50 m L清水预处理后干旱处理)。干旱胁迫5 d后,通过比较暗适应下PSII最大光化学量子产量Fv/Fm和PSI最大氧化状态Pm,确定根施和叶片喷施的最佳浓度处理。然后利用光合荧光同步测量系统分析根施和叶片喷施褪黑素对干旱胁迫下番茄叶片气体交换参数,PSII和PSI的光能分配和电子传递速率,类囊体膜的完整性和ATP酶活性的调节。【结果】根施和叶片喷施不同浓度褪黑素均提高了干旱胁迫下番茄叶片的Fv/Fm和Pm,并且随浓度增加表现出先升高后降低的趋势,L100和R100处理下的Fv/Fm和Pm最大,显著高于对照。L100和R100显著缓解了干旱胁迫对气体交换参数的抑制,其中叶片净光合速率(Pn)分别为2.04和1.71μmol·m~(-2)·s~(-1),显著高于对照(CK1)(0.52μmol·m~(-2)·s~(-1));蒸腾速率(E)分别为0.66和0.54 mmol·m~(-2)·s~(-1),显著高于CK1(0.25 mmol·m~(-2)·s~(-1)),并且显著提高了番茄叶片气孔导度(GH2O)和最大水分利用效率(WUE),降低了气孔限制值(Ls),而L100优于R100处理。快速光响应曲线结果表明L100和R100处理提高了干旱胁迫下番茄幼苗PSII的光化学反应效率Fv'/Fm'及PSII光化学淬灭系数q P,表明褪黑素处理更利于干旱胁迫下番茄叶片PSII光化学反应的高效进行;干旱胁迫下番茄幼苗环式电子传递速率得到显著加强,而L100和R100处理降低了环式电子传递速率,但加强了线性电子传递速率,且L100处理下番茄叶片ETRI和ETRII均高于R100处理;L100、R100处理提高了干旱胁迫下番茄叶片的Y(I)、Y(II),表明褪黑素处理有利于干旱胁迫下番茄叶片吸收光能向光化学反应的方向分配;暗适应后,L100和R100处理番茄叶片P515诱导曲线均高于CK1,照光后,CK0处理番茄幼苗P515信号快速下降,其次是L100和R100处理,而CK1处理降低较慢,表明褪黑素具有保护叶绿体类囊体膜和ATP合成酶免受干旱胁迫伤害的作用。【结论】根施和叶片喷施外源褪黑素能缓解干旱胁迫对番茄幼苗光合性能的抑制,加强光合运转效率,而叶片喷施是一种更简单高效的处理方式;褪黑素能加强作物光合作用对环境胁迫的适应性,对于农作物的生长发育具有调节作用。 相似文献
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外源NO对缺氮胁迫下棉花幼苗形态及生长的调控效应 总被引：4，自引：0，他引：4
【目的】探讨外源一氧化氮（nitric oxide,NO）对缺氮胁迫下棉花幼苗不同部位叶片以及不同直径范围根系等形态特征及生长情况的影响,分析不同浓度NO对棉花形态生长的调控效应,为外源NO调控棉花生长发育提供理论依据。【方法】在光照培养室内采用水培方法,以农大棉8 号为供试品种,设7 个不同处理,其中以Hoagland全营养液培养的棉花幼苗为对照（CK）,以缺氮Hoagland营养液培养的棉花幼苗为外源NO处理对象,利用外源NO供体硝普钠（sodium nitroprusside,SNP）处理棉花幼苗,设置6 个浓度梯度0 μmol·L-1（T0）、50 μmol·L-1（T1）、100 μmol·L-1（T2）、200 μmol·L-1（T3）、500 μmol·L-1（T4）和1 000 μmol·L-1（T5）,研究不同NO水平对缺氮胁迫下棉花幼苗叶面积、根系形态、耗水量及干物重的影响。【结果】缺氮胁迫抑制棉花幼苗地上部以及地下部的生长,抑制棉花幼苗叶片数和叶面积的增加,降低了幼苗细根（0.05-0.20 mm）、中等根（0.2-0.45 mm）的根长、根表面积、根体积,减少了耗水量以及干物重。不同浓度外源NO对缺氮胁迫下棉花幼苗地上及地下部生长情况的影响不同。低浓度外源NO（SNP浓度为50-100 μmol·L-1）能缓解缺氮胁迫对棉花幼苗的伤害,显著促进棉花幼苗上部和下部叶片的生长,促进细根和中等根生长,增加细根和中等根的根长、根表面积及根体积,增加棉花幼苗耗水量,显著增加幼苗干物重。当SNP浓度大于100 μmol·L-1后,随浓度增加,其缓解作用下降。幼苗叶片数、上部和下部叶片的叶面积、细根和中等根的根长、根表面积、根体积、耗水量以及干物重均下降。综合分析认为氮素缺乏环境下,不同浓度外源NO通过影响棉花幼苗地上部以及根系的生长来缓解缺氮胁迫,以100 μmol·L-1 SNP处理的棉花幼苗生长最好,而高浓度的SNP则加剧缺氮胁迫对棉苗的抑制。【结论】缺氮胁迫下棉花幼苗长势减弱,适宜浓度外源NO（SNP浓度为50-100 μmol·L-1）能够在一定程度上缓解缺氮胁迫对棉花幼苗造成的伤害,促进棉花幼苗地上和地下部的生长,提高棉花幼苗对缺氮胁迫的耐性。其中以100 μmol·L-1 SNP缓解效果最显著。 相似文献
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Inoculation of wheat(Triticum aestivum L.) leaves with wheat powdery mildew fungus(Blumeria graminis f. sp. tritici) induces the cell death in adventitious roots. Reactive oxygen species(ROS) play a key role in respond to biotic stress in plants. To study the involvement of ROS and the degree of cell death in the wheat roots following inoculation, ROS levels and microstructure of root cells were analyzed in two wheat cultivars that are susceptible(Huamai 8) and resistant(Shenmai 8) to powdery mildew fungus. At 18 d after powdery mildew fungus inoculation, only Huamai 8 displayed the leaf lesions, while root cell death occurred in both varieties. Huamai 8 had a high level of ROS accumulation, which is associated with increased root cell degradation, while in Shenmai 8, there was little ROS accumulation correlating with slight root cell degradation. The molecular study about the expression levels of ROS scavenging genes(MnSOD and CAT) in wheat roots showed that these genes expression decreased after the leaves of wheat was inoculated. The difference between Huamai 8 and Shenmai 8 on subcellular localization of H2 O2 and O2–· was corresponded with the different down-regulation of the genes encoding for superoxide dismutase and catalase in two wheat cultivars. These results suggested that ROS were involved in the process by which powdery mildew fungus induced cell death in wheat roots. 相似文献
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Horizontal gene transfer from wild species of soya (G. soja) to cultural species (G. max (L.) Merr.)
A. Ya. Ala V. S. Ala T. P. Tuchkova E. T. Chekrysheva L. K. Kashuba Van Lan 《Russian Agricultural Sciences》2013,39(3):214-217
Transformation of genetic information from the wild species of soya (G. soja) to the cultural species (G. max) was distantly carried out by means of horizontal spontaneous gene transfer in field conditions. 相似文献
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Effects of sodium benzoate on growth and physiological characteristics of wheat seedlings under compound heavy metal stress 下载免费PDF全文
下载免费PDF全文 LIANG Pan-pan ZHAO Chen LIN Yuan GENG Ji-jia CHEN Yuan CHEN De-hua ZHANG Xiang 《农业科学学报》2020,19(4):1010-1018
In this study, we investigated the effect of exogenous sodium benzoate on wheat seedlings(Yangmai 16) grown under heavy metal stress. The results showed that 2.4 mmol kg~(–1) of heavy metals significantly inhibited growth and delayed emergence of wheat seedlings. Under compound heavy metal stress, application of 2–4 g L~(–1) sodium benzoate significantly increased(P0.01) chlorophyll content and chlorophyll fluorescence parameters F_v/F_m and F_v/F_o of wheat, compared to the control(water treatment). Further analysis showed that application of 2–4 g L~(–1) sodium benzoate alleviated osmotic stress by promoting the accumulation of osmolytes such as soluble proteins and free proline, increased the activity of superoxide dismutase(SOD) and reduced malondialdehyde content(MDA). In contrast, higher concentrations of sodium benzoate solution(6 g L~(–1)) inhibited the growth of wheat seedlings and even caused damage to seedlings. Correlation analysis showed that when the sodium benzoate concentration was in the range of 1.97–3.12 g L~(–1)(2016) and 1.58–3.27 g L~(–1)(2017), values of chlorophyll and its components, root activity, SOD activity, soluble protein, and free proline content were the highest. When the sodium benzoate concentration was raised to 2.59 g L~(–1)(2016) or 3.02 g L~(–1)(2017), MDA content was the lowest. Ultimately, exogenous sodium benzoate(2–4 g L~(–1)) facilitates root development and improves the root activity of wheat seedlings grown under compound heavy metals stress, thereby effectively alleviating the damage of compound heavy metal stress in wheat seedlings. 相似文献