Population structure analysis and marker trait association in selected set of Indian tomato (Solanum lycopersicum L.) varieties under high temperature condition

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...     

Effects of high temperature on spikelet sterility in rice (Oryza sativa L.): association between molecular markers and allelic phenotypic effect in field condition

Genetic Resources and Crop Evolution - Rice varieties are generally bred for higher yield but may possess genomic regions conferring tolerance to abiotic stresses. Climate change driven heat stress...     

Selection of reference genes for quantitative real-time PCR analysis in Lathyrus sativus L. under different development stages and drought stress

Genetic Resources and Crop Evolution - Grass pea (Lathyrus sativus L.) is a robust legume crop with high protein content and good stress tolerance. However, it needs genetic improvement due to the...     

Efficiency of screening criteria for drought tolerance in chickpea

Crop drought tolerance improvement is one of the most challenging objectives of plant breeding programs. Developing an efficient screening technology and access to genetic variation for the traits contributing toward drought tolerance are major steps in this direction. To go in this quest, an experiment was conducted under controlled condition in a greenhouse. Nine Kabuli chickpea genotypes were grown under well-watered condition (85–90% field capacity (FC)) until start of flowering. Then, the following water treatments were imposed: well-watered, intermediate (55–60% FC), and severe (25–30% FC) drought stress. Physiological and agronomical traits were compared under different water treatments. Drought stress and genotypes interaction was significant in all measured traits, indicating that various genotypes responded differently to drought stress. Among measured traits, electrolyte leakage, stomatal conductance, yield components, and harvest index exhibited the highest variations. Yield components and stomatal conductance showed maximum reduction under drought stress and in susceptible known genotype, ILC3279, reduction reached up to 95%. Principal component analysis indicated that relative water content, photochemical efficiency of photosystem II, and stomatal conductance are the physiological traits with greater contribution toward drought tolerance. Therefore, these traits should be evaluated ahead of many other traits in making selections for drought-tolerant chickpea genotypes.     

Morpho-physio and anatomical characterization of the indigenous Himalayan crabapple: Malus baccata (L.) Borkh. (Rohru) and exotic Malus pumila Mill. for dwarfing traits

Genetic Resources and Crop Evolution - The wild Malus germplasm is considered as a gene reservoir for various biotic and abiotic stresses tolerance/resistance genes, including important novel...     

Genetic evidence of stable northward extension of Pinus thunbergii Parl. forests in the Democratic People’s Republic of Korea

Genetic Resources and Crop Evolution - Japanese black pine (Pinus thunbergii Parl.) with high salt tolerance may be an important constitutive element sustaining terrestrial ecosystem by playing a...     

Diversification of maize (Zea mays L.) through teosinte (Zea mays subsp. parviglumis Iltis & Doebley) allelic

Genetic Resources and Crop Evolution - Zea mays ssp. parviglumis is the progenitor of maize and assume to have tolerance against various biotic and abiotic stresses. It...     

Biochemical markers of environmental stress tolerance in finger millet [Eleusine coracana (L.) Gaertn.] germplasm of Central Himalayan Region

Genetic Resources and Crop Evolution - Availability of the germplasm of suitable crops for cultivation in environmental stress prone and resource poor terrains is crucial for food security in these...     

New selection strategies for determining the traits contributing to increased grain yield in wheat (Triticum aestivum L.) under aluminum stress

Genetic Resources and Crop Evolution - Finding the suitable traits that mediate grain yield under stress condition represent an important challenge to plant breeders in order to improve production....     

An assessment on CRISPR Cas as a novel asset in mitigating drought stress

Genetic Resources and Crop Evolution - Drought stress is currently one of the major threats to the global food security as it primarily is the main cause behind yield loss and hence overall...     

Soil microbiomes vary in their ability to confer drought tolerance to Arabidopsis

Drought is a major constraint on agricultural production. Crop genetic improvement for drought tolerance has received much attention and there is ample information about the ability of specific soil microbes to influence drought tolerance in plants. However, in nature, plants interact simultaneously with an array of beneficial, benign and pathogenic microbes. There is a need to understand the cumulative effect of these multiple interactions on a plant's ability to overcome abiotic stresses such as drought. The objective of this research was to investigate the potential of whole soil microbiomes to help Arabidopsis thaliana plants deal with drought stress under in vivo conditions. A sympatric microbiome (i.e., having a history of exposure to Arabidopsis at a natural site) significantly increased plant biomass under drought conditions, but caused earlier death rates as a consequence of drought; whereas, the two non-sympatric soils did not influence Arabidopsis biomass. Consistent with this, we observed reduced expression levels for several Arabidopsis drought response marker genes (ATDI21, DREB1A, DREB2A, and NCED3) in the sympatric Arabidopsis soil treatment. Pyrosequencing analysis of the three soil microbiomes used in this study identified 84 bacterial OTUs (3% genetic distance) from 41 genera (Burkholderia, Phormidium, Bacillus, Aminobacter, Acidiphilum and among others) that were significantly higher in the sympatric Arabidopsis soil, as compared to the two non-sympatric soils. In conclusion, we have identified a robust set of Arabidopsis-associated microbes that when present in the soil can modify the plant's ability to sense abiotic stress and increase its biomass production.     

Differential tolerance of bush bean cultivars to excess manganese in solution and sand culture

Nineteen bush bean cultivars were screened for tolerance to excess Mn in nutrient solution and sand culture experiments. Seven‐day‐old seedlings were treated with full strength Hoagland No. 2 nutrient solution containing different Mn concentrations for 12 days in the greenhouse.

Cultivars showing the greatest sensitivity to Mn toxicity were ‘Wonder Crop 1’ and ‘Wonder Crop 2'; those showing the greatest tolerance were ‘Green Lord’, ‘Red Kidney’ and ‘Edogawa Black Seeded’.

Leaf Mn concentration of plants grown in sand culture was higher than that for plants grown in solution culture. The lowest leaf Mn concentration at which Mn toxicity symptoms developed, was higher in tolerant than in sensitive cultivars. The Fe/Mn ratio in the leaves at which Mn toxicity symptoms developed, was higher in the sensitive cultivars than in the tolerant ones.

We concluded that Mn tolerance in certain bush bean cultivars is due to a greater ability to tolerate a high level of Mn accumulation in the leaves.     

辐照杂合材料结合花药培养技术育成早籼新品种赣早籼56号

赣早籼 5 6号系江西农业大学农学院运用辐射处理及花药培养与有性杂交相结合的综合育种技术育成的早籼新品种 ,该品种具有优质、高产、耐高温逼熟、熟期适宜、高抗稻瘟病等优良性状 ,2 0 0 4年 3月 1 9日通过了江西省农作物品种审定委员会的审定与命名。本文主要介绍了赣早籼 5 6号的选育经过、主要特征特性及推广应用价值。     

Differences Among Rice Cultivars in their Adaptation to Low Ionic Strength Solution with Toxic Level of Aluminum that Mimics Tropical Acid Soil Conditions

Nutrient deficiencies are often an additional growth-limiting factor in tropical acid soils. Considering the potential interactions between Al stress and low-nutrient stress, differences among rice cultivars for Al tolerance, low-nutrient tolerance, and combined stress tolerance were investigated. The main objective of this study was to identify the predominant growth-limiting factor in tropical acid soils. Tolerance to low nutrient stress and combined stress did not show any relationship with aluminum (Al) tolerance indicating that these stress factors act independently. Al-tolerant cv. Rikuu-132 was tolerant to combined stress. Conversely, highly Al-sensitive cv. BR34 was most tolerant to combined and low nutrient stress. Combined stress tolerance of shoot was positively correlated with calcium (Ca) content of shoot. The results indicate that Al tolerance alone is not adequate for superior performance on most acid soils. Tolerance to combined stress factors would be needed to improve productivity of rice on low fertility acid soils.     

Evaluation of switchgrass entries for acid soil tolerance

Abstract

Crop and forage yields are significantly reduced by strong soil acidity throughout much of the northeastern United States. Switchgrass (Panicum virgatum L.) is a valuable perennial warm‐season pasture species generally regarded as tolerant to stress conditions, i.e., infertile, dry, or low pH soils; however, switchgrass has not been studied for variability in acid soil tolerance. The objectives of this study were (a) to compare the responses of different switchgrass entries to soil acidity, and (b) to identify selected agribotanical trait response to unlimed (‐L) and limed (+L) soil. Sixteen entries (cultivars, germplasms, and breeding populations) were studied in short‐ and meso‐term experiments. Unlimed (pH 4.9) and limed (pH 5.9) treatments of a sandy loam soil (Typic Dystrochrept) were used in both experiments. Switchgrass seedlings were exceptionally tolerant of soil acidity in the short‐term experiment. In the meso‐term experiment, acid soil stress significantly reduced all agribotanical traits (plant height, leaf area, top weight, and root weight) determined in the study when compared to +L plants. There were significant, positive correlations among the agribotanical traits; however, the effect of ‐L soil was more obvious on root weight and less so on plant height. Entries 922 GST6, 920 AST6, 921 DST6, and 922 BST6 showed superior general adaptability and promising forage production, while cultivars Carthage and PI 142138 were acid soil tolerant with low productivity. Our data suggests that selection for increased acid soil tolerance in switchgrass may be possible and would result in improved productivity of this grass in acid soil environments.     

植物对水分胁迫的分子响应及其遗传改良研究进展

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。     

An inventory of crop wild relatives of the Maltese Islands

Genetic Resources and Crop Evolution - Crop wild relatives are sources of genetic diversity valuable for crop improvement to address the challenges faced by agriculture in withstanding stressors...     

基于叶片电信号边际谱熵的玉米耐盐碱性无损评价方法

为了探索能够早期、灵敏、在位和无损检测与评价植物耐盐碱性的方法,将Na Cl、Na2SO4、Na HCO3和Na2CO3配置成复合盐碱溶液对耐盐碱性较弱的玉米品种郑单958和耐盐碱性较强的玉米品种名玉20的玉米幼苗进行盐碱胁迫,采集了盐碱胁迫过程中郑单958和名玉20幼苗叶片电信号,应用HHT(Hilbert-Huang transformation)方法得到了2种玉米叶片电信号的边际谱,分析了盐碱胁迫过程中2个玉米品种叶片电信号边际谱熵MSE(marginal spectrum entropy)变化的差异和生物学意义。结果显示:盐碱胁迫过程中,郑单958叶片电信号的MSE表现出不断下降的趋势,叶片中丙二醛MDA(malondialdehyde)含量迅速升高;名玉20的MSE表现出波动性的变化,MDA含量变化不大,表明郑单958叶片细胞的离子跨膜运输被抑制,名玉20的叶片细胞存在着复杂的代谢调节,盐碱胁迫造成的叶片细胞膜脂过氧化可能是叶片电信号MSE变化的原因。研究发现,盐碱胁迫下耐盐碱性不同的2个玉米品种的叶片电信号响应指数RI(response index)差异明显,在胁迫2、3和4 d时郑单958的RI值分别比名玉20增长了42%、193%和332%。根据RI值的大小有可能对盐碱胁迫下玉米叶片细胞离子运输和细胞膜伤害的影响程度进行灵敏和早期的定量诊断,进而实现对玉米幼苗期耐盐碱性强弱的在位和无损伤的评价。     

冀东野生大豆(Glycine soja)耐盐碱性鉴定及耐性生理指标测定

为充分利用盐碱地资源,明确野生大豆耐盐碱生理机制,本研究对采集于冀东地区的349份野生大豆种质资源进行耐盐碱性鉴定,测定了高耐材料2010-12和敏感材料2012-34、2012-49在0、100和200 mmol·L^-1盐碱胁迫下的丙二醛、脯氨酸和可溶性糖含量、电解质外渗率以及脯氨酸代谢关键酶吡咯琳-5-羧酸合成酶(GmP5CS)、吡咯琳-5-羧酸还原酶(GmP5CR)、脯氨酸脱氢酶(GmPDH)及谷胱甘肽S-转移酶19(GsGST19)相关基因的表达量。结果表明,表现耐性等级1级的高耐材料有2份(Yong 2和2010-12),表现耐性等级2级的耐性材料有22份,表现耐性等级3、4、5级的材料各有80、77和161份。与CK相比,高耐野生大豆材料2010-12在盐碱胁迫下脯氨酸及可溶性糖含量显著升高,丙二醛含量及电解质外渗率无显著差异。在高耐盐碱野生大豆材料中,GmP5CS、GmP5CR和GsGST19基因表达量上调,GmPDH基因表达量下调。以上结果表明高耐野生大豆材料在盐碱胁迫下脯氨酸合成通路激活,脯氨酸含量升高,说明脯氨酸在野生大豆对抗盐碱胁迫中发挥重要作用。本研究筛选的高耐盐碱野生大豆材料可为培育耐盐碱栽培大豆提供优异种质。     

Heat stress and plant development: role of sulphur metabolites and management strategies

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.