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1.
Drought and heat are major environmental stresses that continually influence plant growth and development. Under field conditions, these stresses occur more frequently in combination than alone, which magnifies corresponding detrimental effects on the growth and productivity of agriculturally important crops. Plant responses to such abiotic stresses are quite complex and manifested in a range of developmental, molecular, and physiological modifications that lead either to stress sensitivity or tolerance/resistance. Maize (Zea mays L.) is known for its sensitivity to abiotic stresses, which often results in substantial loss in crop productivity. Bioaugmentation with plant growth-promoting rhizobacteria (PGPR) has the potential to mitigate the adverse effects of drought and heat stresses on plants. Hence, this is considered a promising and eco-friendly strategy to ensure sustainable and long-term maize production under adverse climatic conditions. These microorganisms possess various plant growth-promoting (PGP) characteristics that can induce drought and heat tolerance in maize plants by directly or indirectly influencing molecular, metabolic, and physiological stress responses of plants. This review aims to assess the current knowledge regarding the ability of PGPR to induce drought and heat stress tolerance in maize plants. Furthermore, the drought and heat stress-induced expression of drought and heat stress response genes for this crop is discussed with the mechanisms through which PGPR alter maize stress response gene expression.  相似文献   

2.
Heat stress is a major environmental stress limiting wheat productivity in most cereal growing areas of the world. The objective of this study was to evaluate heat stress tolerance in durum wheat (Triticum turgidum var. durum) genotypes. For this purpose, 45 genotypes were grown during two growing seasons (2012–2013 and 2013–2014) under non-stress (normal sowing) and heat-stress (late sowing) conditions. The heat tolerance indices were calculated based on grain yield under normal sowing (Yp) and late sowing (Ys) conditions. Results of combined analysis of variance showed the significant influences of heat stress on grain yield as well as significant differences among genotypes for grain yield and the indices. Results of correlation coefficients and multivariate analyses revealed that the stress tolerance index (STI), geometric mean productivity and mean productivity (MP) indices were the most profitable criteria for selection of heat tolerant and high yielding genotypes. Using STI, GMP and MP, the genotypes G29, G41 and G10 were found to be the best genotypes with relatively high yield and suitable for both normal and heat stressed conditions. Based on biplot analysis using Yp, Ys and the indices, it was possible to identify superior genotypes across the conditions.  相似文献   

3.
Temperature plays a crucial role in plants development whereas a sudden rise may cause severe consequences. Heat stress impairs plant growth, photosynthesis, pollen development and reproduction. The plant photosynthetic efficiency is mainly reduced by the over production of reactive oxygen species, denaturation of heat shock proteins and alteration in many enzymes activities. Unlike drought stress, plants have developed a very few mechanisms to encounter heat stress problem. Recently, the use of nutrients such as sulphur has emerged as one of the efficient methods to enhance plant tolerance against high temperature stress. The mechanistic understanding of sulphur-based strategies could be very helpful to sustain plant development and global food supplies in future hotter climates. The present review mainly focuses on (1) high temperature induced changes in plant functions, (2) possible roles of sulphur metabolites in heat stress tolerance and (3) possibilities of using sulphur as a management strategy. Moreover, the review consolidates the future research needs that must focus on (i) heat tolerant germplasm screening; (ii) sulphur dose optimisation, application method and crop growth stages response; (iii) finding of sulphur induced heat tolerance mechanisms and (iv) the use of omic approaches to discover sulphur metabolites role in heat stress tolerance.  相似文献   

4.
Drought stress affects plant growth and causes significant issues in meeting global demand for food crops and fodder. Drought can cause physiological, physicochemical, and morphological changes in plants, which negatively affects plant growth and productivity. To combat this under the increasing global threat of water shortage and rapid population expansion, it is crucial to develop strategies to meet global food demands. Plant growth-promoting rhizobacteria (PGPR) may provide a safe solution to enhancing crop yields through various mechanisms. These soil bacteria can provide drought tolerance to crop plants, allowing them to survive and thrive in water-scarce conditions. Productions of phytohormones, free radical-scavenging enzymes, and stress-combating enzymes that can increase tolerance to drought-induced stress are key features of plant-associated microbial communities. This review summarizes the beneficial properties of microbes that help plants tolerate water scarcity and highlights the bacterial mechanisms that enhance drought tolerance in plants.  相似文献   

5.
Abstract

Improvement of agricultural water use efficiency is of major concern with drought problems being one of the most important factors limiting grain production worldwide. Effective management of water for crop production in water-scarce areas requires efficient approaches. Increasing crop water use efficiency and drought tolerance by genetic improvement and physiological regulation may be a means to achieve efficient and effective use of water. A limited water supply inhibits the photosynthesis of plants, causes changes of chlorophyll contents and components and damage to photosynthetic apparatus. It also inhibits photochemical activities and decreases the activities of enzymes in plants. Water stress is one of the important factors inhibiting the growth and photosynthetic abilities of plants through disturbing the balance between the production of reactive oxygen species and the antioxidant defence, causing accumulation of reactive oxygen species which induce oxidative stress to proteins, membrane lipids and other cellular components. A number of approaches are being used to enhance water use efficiency and to minimize the detrimental effect of water stress in crop plants. Proper plant nutrition is a good strategy to enhance water use efficiency and productivity in crop plants. Plant nutrients play a very important role in enhancing water use efficiency under limited water supply. In this paper we discuss the possible effective techniques to improve water use efficiency and some macronutrients (nitrogen, phosphorus, potassium, calcium and magnesium), micronutrients (zinc, boron, iron, manganese, molybdenum and chloride), and silicon (a beneficial nutrient) in detail to show how these nutrients play their role in enhancing water use efficiency in crop plant.  相似文献   

6.
植物对水分胁迫适应性的生理机理已相继在水稻、小麦、玉米、高梁等作物中得以报道。然而,有关这些性状的遗传控制及其在与逆境下作物生产的关系却了解甚少,由此阻碍了抗性遗传改良的进展。随着基因定位、基因组图谱、基因转移等分子生物学技术的发展,对植物抗逆性状进行分子剖析成为可能。本文综述了主要禾谷类作物对水分胁迫的抗性生理及遗传研究上的最新进展,讨论了植物抗性遗传改良的发展前景。  相似文献   

7.
Plant cell adjustments in water and osmotic status in response to heat, cold, and osmotic stress were investigated using microcultured plants from four assessions of Lycopersicon. Changes in plant water potentials were determined with an osmometer solution method, and osmolarity by a cell sap extraction method. Heat stress decreased water potential (raised osmolarity) and cold stress increased water potential (depressed osmolarity) for all species, but the magnitude of the adjustment was significantly greater for L. peruvianum (a drought resistant genotype). Microcultures produced on growth medium with elevated levels of osmotic agents (sorbitol, dextran, or glucose) developed correspondingly higher cell sap osmolarity. Plant water potential shifted in the same direction, but not to the same degree, as osmotic potential in response to stress. Since osmotic adjustment is a reported mechanism of stress (salt, temperature, and water deficit) tolerance, these tests suggest a method for prescreening of germplasm at the microculture plant level.  相似文献   

8.
Amrutha  V.  Shanija  S.  Beena  R.  Nithya  N.  Jaslam  M. P. K.  Soni  K. B.  Viji  M. M. 《Genetic Resources and Crop Evolution》2022,69(1):183-207
Genetic Resources and Crop Evolution - Heat stress is an important abiotic stress affecting the productivity of tomato. Understanding the physiological basis of heat tolerance is needed to adapt to...  相似文献   

9.
The enhancement in both frequency and intensity of high temperature, besides its large variability will result in up to 40% yield reduction in rice by the end of 21st century. Vegetative growth in rice continues with day time temperature up to 40°C but development of florets is extremely sensitive to temperature higher than 35°C. The effect of night time temperature stress is even more adverse than day. Heat stress results in deprived anther dehiscence, impaired pollination and abnormal pollen germination that cause floret sterility. The decrease in pollen viability is presumably caused by imbalance in proteins expression, abandoned biosynthesis, partitioning and translocation of soluble sugars, imbalance in phytohormones release, and loss of pollen water content. Rice responds to heat stress by adjusting various physiochemical mechanisms viz., growth inhibition, leaf senescence and alteration in basic physiological processes. Antioxidant enzymes, calcium and iron also play an important role in managing heat stress. Response of rice to heat stress varies with plant ecotype, growth stage, heat intensity and time of stress application. High temperature stress can be managed by developing heat-tolerant genotypes. Rice breeding and screening may be based on anther dehiscence, pollen tube development and pollen germination on stigma.  相似文献   

10.
Soil salinity, drought, metal toxicity, and ultraviolet-B radiation were major abiotic stresses that limit plant growth and productivity by disrupting the plants' cellular ionic and osmotic balance; legumes, a diverse plant family, suffered from these abiotic stresses. Although silicon (Si) is generally considered non-essential for plant growth and development, Si uptake by plants could facilitate plant growth by reducing biotic and abiotic stresses. There is however, a lack of systematic study on Si uptake benefits and mechanism on legumes because legumes reject Si uptake. Here, we reviewed the beneficial role of Si in enhancing abiotic stress tolerance in legumes and highlighted the mechanisms through which Si could improve abiotic stress tolerance in legumes. Future research needs for Si mediated alleviation of abiotic stresses in legumes are also discussed.  相似文献   

11.
为从蛋白质水平揭示耐热与热敏感水稻花药响应高温胁迫的分子机制,本研究以耐热水稻品系996和热敏感水稻品系4628为材料,采用iTRAQ技术对高温和适温条件下水稻花药进行差异蛋白质组学分析。结果表明,在996高温-996适温、4628高温-4628适温、996高温-4628高温和996适温-4628适温4个比较组中,共筛选到957个差异表达蛋白,其中上调表达蛋白398个,覆盖率达20%以上的蛋白占鉴定总蛋白的50.96%。GO分析显示,抽穗开花期花药差异蛋白主要集中于代谢过程和细胞过程,在细胞组成方面主要分布于胞内部分、细胞器和细胞,分子功能主要涉及催化活性、绑定等。花药差异蛋白通路分析显示,来源于bZIP和DOF家族的2个转录因子差异表达,DOF家族基因上调,bZIP家族基因下调;18个HSPs基因中大部分表达上调;与植物激素和信号传导相关基因大部分表达下调;10个活性氧(ROS)相关基因中5个表现为上调;与次生代谢相关基因大部分下调。本研究结果为揭示水稻花药高温胁迫的应答分子调控机制提供了一定的理论基础。  相似文献   

12.
肉鸡热休克蛋白70 mRNA荧光定量PCR方法的建立和优化   总被引:1,自引:0,他引:1  
对适应性饲养到30日龄时的60只肉鸡进行热应激处理,通过热休克蛋白70(heatshockprotein70,HSP70)mRNA荧光定量PCR(fluorescencequantitativePCR,FQ-PCR)方法检测热应激处理肉鸡组织中HSP70mRNA含量。虽然受试鸡肝脏和心脏的HSP70mRNA水平在热应激6h时略低于对照组(P>0.05),但随持续性高温应激时间的延长,HSP70mRNA水平逐渐升高,热应激18h时应激肉鸡肝脏和心脏HSP70mRNA水平达最高水平,明显高于对照组(P<0.01)。实验选用3-磷酸甘油醛脱氢酶基因(GAPDH)作为内参照,体外转录的RNA和阳性质粒作为两种标准品。结果显示,实验所建立和优化的FQ-PCR反应体系是理想的。  相似文献   

13.
  【目的】  丛枝菌根真菌(AMF)可以显著提高植物对逆境胁迫的抵抗能力,本文综述了国内外针对代表性组学技术(转录组学、蛋白质组学和代谢组学)在AMF提高植物抗逆领域(干旱、温度、盐碱、重金属)的研究进展,分析了在逆境胁迫下,植物–菌根共生体在分子层面上的应答调控机理,为深入理解AMF提高植物耐逆的分子机理提供一定的科学依据。  主要进展  植物主要通过根系与AMF建立共生关系,进而从土壤中吸收更多的水分和营养物质,提高植物对非生物胁迫的抵抗能力。菌根植物在转录、翻译以及表观遗传层面应答非生物胁迫。AMF在不同程度上上调或下调某些与非生物胁迫相关基因的转录或蛋白的翻译及降解,从而提高植物对非生物胁迫的抵抗能力,维持植物的生长发育,提高其对水分和营养物质的吸收和利用效率。通过转录组学、蛋白质组学和代谢组学分析关键基因、蛋白及代谢物的变化,为深入挖掘AMF提高植物抗逆机理提供理论依据。  研究展望  揭示丛枝菌根共生体抗逆机理的组学技术研究仍处于起步阶段,单一组学的应用限制了信息表达的完整性和深层次网络调控机理的精确性。随着测序技术和手段在速度、精度等方面的提高以及生物信息学的更新发展,AMF提高植物抗逆性组学的研究将朝着多组学结合的方向发展,使研究者能够从多角度全面探究植物相关研究的分子机理,这有助于更全面地理解植物相关生命活动的分子调控规律。  相似文献   

14.
植物非生物逆境相关锌指蛋白基因的研究进展   总被引:3,自引:0,他引:3  
向建华  李灵之  陈信波 《核农学报》2012,26(4):666-672,716
植物能够适应多种逆境主要是通过改变其基因表达和代谢途径来实现的,因此研究这些基因表达和功能对提高植物耐逆性具有重要意义。锌指蛋白是一类具有手指状结构域的转录因子,这种结构域由锌离子与多个半胱氨酸和(或)组氨酸组成,锌离子在稳定其结构和发挥调控功能方面具有关键作用。植物锌指蛋白在植物耐逆性方面具有重要作用。本文综述了近几年来从拟南芥(Arabidopsis thaliana)、水稻(Oryza sativa)、小麦(Triticum aestivum)、番茄(Solanum lycopersicum)等植物中克隆的与非生物逆境相关锌指蛋白基因的研究成果,重点阐述了其基因表达部位、受逆境诱导情况及转基因植株的耐逆性等。目前的研究结果表明锌指蛋白能够调控耐逆相关基因的表达,在植物逆境代谢中发挥重要作用,因此可以利用锌指蛋白基因进行作物耐逆性的遗传改良,提高作物的耐逆能力。  相似文献   

15.
奶牛热应激指数的研究现状及问题分析   总被引:3,自引:1,他引:2  
热应激严重影响奶牛的生产力、繁殖力和福利。为降低奶牛热应激的风险,国内外学者一直在寻求预测和评估热应激的方法,在诸多方法中综合多个环境因子的热应激指数模型目前最为常用。为避免在指数选择上的盲目性,该文系统地梳理了温湿指数、基于温湿指数的修正指数和其他指数,对比分析了不同评价指数在奶牛热应激时表征指标的差异,其中涉及指数阈值、环境因子及传热性质、奶牛生理反应与指数间的关系。目前奶牛热应激指数存在的问题有指数包含的环境参数不能反映奶牛与环境的换热机理,以及环境条件不同导致评价结果差异较大等。随着数字化技术的应用,多参数获取技术得到了根本性改变,有必要提出更加精细的指数评价模型以满足提高家畜生产力、实现福利化养殖的需要。作者对未来奶牛热应激指数发展方向上的建议是:1)应涉及更多的环境参数,并且环境参数应体现出一定的换热机理;2)构建特定气候类型指数的同时,还应适当考虑指数在其他环境下的适应性;3)指数要有适用信息和阈值,指数的阈值要能够进行动态调整以扩大其适用范围;4)指数的构建应综合考虑动物因素和环境因素,可考虑与动物热平衡原理相结合。  相似文献   

16.
The aim of present investigation has been to explore the effect of sulfur application on plant metabolism, seed yield and seed quality in soybean. The sulfur was supplied in different doses ranging as 1, 2, 4, 6 and 8 meq S L?1. Plant supplied with 4 meq S L?1 showed optimal growth. Plant growth and dry matter was reduced under sulfur deficiency (1 and 2 meq S L?1) and toxicity (6 and 8 meq S L?1). Application of sulfur increases the tissue sulfur and cysteine concentration in both leaves and seeds. The critical concentration for deficiency (CCD) and toxicity (CCT) of sulfur was observed 0.194 to 0.277% dry weight respectively. Pod yield and seed yield was also suppressed in sulfur deficiency and toxicity. In leaves sugar (reducing, non-reducing and total sugar) and starch was found to be accumulated while in seeds both were depleted under sulfur deficiency and toxicty. Seed storage proteins (albumins, globulins, glutelins and prolamins) were also reduced under sulfur stress. Thus, we conclude that sulfur deficiency and toxicity both affects the plant metabolism, yield and seed quality in terms of carbohydrates and storage proteins of soybean.  相似文献   

17.
低温是影响植物生长发育和作物产量的非生物胁迫因子之一。植物在长期的进化过程中,通过调节自身的生理及分子变化,形成了对低温胁迫的适应能力。脱水素是一类晚期胚胎丰富蛋白,可保护植物细胞内蛋白质和膜结构等不被低温破坏。不同植物中脱水素的过量表达能够提高植物的低温抗性,植物脱水素的表达和蛋白质的积累与植物耐低温能力密切相关。本文对SKn、Kn、YnSKn、KnS和Yn Kn型脱水素在植物抵御低温胁迫过程中的作用进行综述,旨在为进一步利用脱水素进行植物抗低温分子育种研究提供参考。  相似文献   

18.
《CATENA》2005,59(1):55-68
A field survey of an evergreen Mediterranean woodland area in NE Spain on three silica-rich parent materials (granite, granodiorite and schist) was used to test whether parent material had a separate effect on ecosystem functioning in addition to aspect and position on the slope. As expected, vegetation was taller and denser on north-facing slopes and/or lower slope positions. However, parent material appeared to have additional effects, with significant increases in tree height, tree cover, shrub height and ratio of woodland to maquis vegetation from granite towards granodiorite and schist. There was also a parallel increase in mull humus forms, indicating increasing litter breakdown. The lower productivity on granite may be partly attributed to drought stress, as indicated by the greater proportion of shallow soils and the sandy to loamy sand texture. However, nutrient stress may be equally important. Plant N/P ratios were significantly greater on granite, and plant and soil P contents were less than on the other parent materials, suggesting that P-availability was limited on granite. The greater productivity of soils on schist than on granodiorite may reflect less severe drought stress because of their finer texture. These results suggest that parent material is an important factor regulating productivity in Mediterranean ecosystems through varying drought stress and availability of nutrients.  相似文献   

19.
利用青花菜单倍体茎尖筛选耐热变异体   总被引:4,自引:0,他引:4  
用平阳霉素对青花菜“上海4号”和“东村交配”的单倍体茎尖进行诱变处理,以高温作为选择压力,获得一批耐热性明显比原始品种提高的单倍体变异体。经过染色体加倍后,通过热胁迫条件下电导率的测定,筛选出9份细胞膜热稳定性比原始品种明显提高的变异体材料。  相似文献   

20.
Thirty five ornamental plants were introduced into the Ahmadi Bioremediated Soil Park to screen and closely monitor the growth performance of these new introductions under the local environmental conditions. Out of these 35 plant species, 15 were planted in both bioremediated and agricultural soils to assess their suitability for growing in bioremediated soils. Data on vegetative growth was recorded to assess the performance of newly-introduced plants, whereas, the heat stress was documented of Bauhinia blakeana, where no visible effects of petroleum pollutants on plant growth were observed. Performance of each plant group is discussed separately in the text. Overall, plant survival was 72.73% for all plant groups. Generally, plants that failed to grow in bioremediated soil also did not survive in the agricultural soil, indicating that they were sensitive to heat stress more than the presence of petroleum contaminants in the soil. New plant species that were able to establish and perform satisfactorily will be used in greenery projects after they are fully naturalized to the prevailing climatic conditions.  相似文献   

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