Effects of Favorable Alleles for Water-Soluble Carbohydrates at Grain Filling on Grain Weight under Drought and Heat Stresses in Wheat

Short heat waves during grain filling can reduce grain size and consequently yield in wheat (Triticum aestivum L.). Grain weight responses to heat represent the net outcome of reduced photosynthesis, increased mobilisation of stem reserves (water-soluble carbohydrates, WSC) and accelerated senescence in the grain. To compare their relative roles in grain weight responses under heat, these characteristics were monitored in nine wheat genotypes subjected to a brief heat stress at early grain filling (37°C maximum for 3 days at 10 days after anthesis). Compared with the five tolerant varieties, the four susceptible varieties showed greater heat-triggered reductions in final grain weight, grain filling duration, flag leaf chla and chlb content, stem WSC and PSII functionality (Fv/Fm). Despite the potential for reductions in sugar supply to the developing grains, there was little effect of heat on grain filling rate, suggesting that grain size effects of heat may have instead been driven by premature senescence in the grain. Extreme senescence responses potentially masked stem WSC contributions to grain weight stability. Based on these findings, limiting heat-triggered senescence in the grain may provide an appropriate focus for improving heat tolerance in wheat.

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Genetic Dissection of Stem Water-Soluble Carbohydrates and Agronomic Traits in Wheat under Different Water Regimes

Journal of Agricultural Science ◽

10.5539/jas.v9n3p42 ◽

2017 ◽

Vol 9 (3) ◽

pp. 42 ◽

Cited By ~ 3

Author(s):

Khan Nadia ◽

Xiaoping Chang ◽

Ruilian Jing

Keyword(s):

Agronomic Traits ◽

Phenotypic Variability ◽

Grain Filling ◽

Wheat Breeding ◽

Water Soluble ◽

Soluble Carbohydrates ◽

Growth Stages ◽

Water Regimes ◽

Water Soluble Carbohydrates ◽

Stem Water

Drought is a major environmental stress threatening wheat (Triticum aestivum L.) productivity worldwide. Although drought impedes wheat performance at all growth stages, it is more critical during the flowering and grain-filling phases and results in substantial yield losses. In this context, stem water-soluble carbohydrates (SWSC) were dissected at flowering and grain filling stages under drought stress (DS) and well-watered (WW) conditions using a population consisted of 116 wheat accessions in this research. The main goal was to dissect the genetic basis of water-soluble carbohydrates and the agronomic traits using association mapping approach and identify linked molecular markers. The results showed significant and positive correlations for stem water-soluble carbohydrates at grain filling (SWSCG) with accumulating efficiency of stem water-soluble carbohydrates (AESWSC) and grain filling efficiency at the late stage (GFEL). The accumulating and grain filling efficiency at grain filling stage could play an important role for SWSC especially under DS condition. Four favorable alleles for plant height (PH) and grain yield (GY) were identified in two water environments. Xbarc78-4A163and Xbarc78-4A155 were variant alleles for PH which were identified in both water regimes. Whereas Xwmc25-2D151 and Xgwm165-4B191 positively linked with GY in WW. Although Xwmc420-4A121and Xwmc112-2D215 were alleles for stem water-soluble carbohydrates at flowering (SWSCF) and SWSCG in DS but the frequency were < 5% so they were considered as rare alleles. These SSR markers which explained significant level of phenotypic variability for chosen traits could be used for selection of genotypes in wheat breeding programs through marker-assisted selection.

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Stem deposition ability in modern winter wheat varieties under different environmental conditions as a physiological marker of their productivity

Visnik ukrains'kogo tovaristva genetikiv i selekcioneriv ◽

10.7124/visnyk.utgis.14.2.689 ◽

2016 ◽

Vol 14 (2) ◽

pp. 203-209 ◽

Cited By ~ 1

Author(s):

G. A. Priadkina ◽

O. V. Zborovska ◽

P. L. Ryzhykova

Keyword(s):

Winter Wheat ◽

Environmental Conditions ◽

Dry Matter ◽

Weather Conditions ◽

Grain Filling ◽

Water Soluble ◽

Soluble Carbohydrates ◽

Main Shoot ◽

Water Soluble Carbohydrates ◽

The Difference

Aim. The search of relationship between characteristics of the stem deposition ability in winter wheat modern varieties and grains productivity under different environmental conditions. Methods. Field, biochemical (soluble stem carbohydrates) methods and mathematical-statistical analysis. Results. The deposition ability of the stem - a difference of content and the total amount of the water-soluble carbohydrates in the stem of the main shoot and weight of its dry matter content in the phases of flowering and full maturity – for 5 varieties of winter wheat in the years significantly different in weather conditions during grain filling were investigated. It is shown that the difference in weight of stem dry matter at the flowering phase and full ripeness and the grain mass of ear significantly varied with different weather conditions during the grain filling, as well as different varieties. A correlation between the mass of a main shoot grain ear with these indices was analyzed. A close positive correlation (r=0.88±0.13) between the grain mass of ear and the difference in weight of stem dry matter at the flowering phase and full ripeness was found. Conclusions. A physiological marker associated with high productivity of ear in different environmental conditions, which is simple to measure and closely linked to weight of grain from an ear was proposed. Keywords: Triticum aestivum L., stem deposited ability, water-soluble carbohydrates, grain productivity.

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Grain filling patterns of barley as affected by high temperature stress

Journal of the Bangladesh Agricultural University ◽

10.3329/jbau.v15i2.35059 ◽

2017 ◽

Vol 15 (2) ◽

pp. 174-181

Author(s):

Md Rasel Rana ◽

Md Masudul Karim ◽

Md Juiceball Hassan ◽

Md Alamgir Hossain ◽

Md Ashraful Haque

Keyword(s):

Heat Stress ◽

Grain Yield ◽

Grain Filling ◽

High Temperature Stress ◽

Water Soluble ◽

Grain Weight ◽

Soluble Carbohydrates ◽

Barley Cultivars ◽

The Mean ◽

Grain Filling Period

Grain filling determines the grain weight, a major component of grain yield in cereals. Grain filling in barley depends on current assimilation and culm reserves (mainly water-soluble carbohydrates). Nowadays barley is facing heat stress problem which is mostly responsible to reduce the yield of barley. A field experiment was conducted at the Field Lab, Department of Crop Botany, BangladeshAgriculturalUniversity, Mymensingh during November 2015 to March 2016 to study the grain filling patterns and the contributions of culm reserves to grain yield under heat stress. The experiment consisted of two factors—barley cultivars and heat stress. The heat stress was imposed by late sowing. The tillers were sampled once a week during grain filling period to determine the changes in dry weights of different parts, viz., leaves, culm with sheath, spikes, and grains; and to examine the contribution of culm reserves to grain yield. The results in the experiment revealed that the grain yield was reduced by 22-28% due to the stress. The grain yield varied from 52 to 150 g m−2 with the mean of 102 g m−2 under control while it varied from 37 to 116 g m−2 with the mean of 75 g m−2 under heat stress. Among the cultivars studied BARI Barley5, BARI Barley2 and BARI Barley1, seemed as high yielders while BARI Barley3, BARI Barley4, BARI Barley6 as the low yielders under heat stress treatment. The reduction in grain yield was attributable mainly to lighter grain weight due to the stress. Heat stress drastically reduced the grain filling duration by 45–50%. However, the stress increased the grain filling rate by 6–53%. The amount of reserves remobilized to grain varied among the cultivars ranging from 4.8 to 12.77 mg spike−1 in control and from 1.73 to 6.25 mg spike−1 in stressed plants. The stressed barley plants exhibited lower accumulation of reserves in culm but they showed almost its complete remobilization to the grain. The contribution of culm reserves to grain yield varied from 1.13 to 19.52%, and 1.09 to 2.11% in control and in stressed plants, respectively. In conclusion, culm reserve is the important attributes in grain yield in Bangladeshi barley cultivars but the contribution remains almost unaffected due the post-anthesis heat stress.J. Bangladesh Agril. Univ. 15(2): 174-181, December 2017

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BIPLOT ANALYSIS FOR IDENTIFICATION OF SUPERIOR GENOTYPES IN A RECOMBINANT INBRED POPULATION OF WHEAT UNDER RAINFED CONDITIONS

Journal of Experimental Biology and Agricultural Sciences ◽

10.18006/2021.9(5).598.609 ◽

2021 ◽

Vol 9 (5) ◽

pp. 598-609

Author(s):

Ashutosh Srivastava ◽

◽

Puja Srivastava ◽

R S Sarlach ◽

Mayank Anand Gururani ◽

...

Keyword(s):

Canopy Temperature ◽

Grain Filling ◽

Water Soluble ◽

Physiological Traits ◽

Soluble Carbohydrates ◽

Biplot Analysis ◽

Water Soluble Carbohydrates ◽

Grain Filling Period ◽

Peduncle Length ◽

Ideal Genotype

Physiological traits of wheat genotypes and their trait relation to drought conditions are important to identify the genotype in target environments. Thus, genotype selection should be based on multiple physiological traits in variable environments within the target region. This study was conducted at Punjab Agricultural University during rabi crop seasons 2012-13 and 2013-14 to study the recombinant inbred lines (RILs) of wheat genotypes derived from traditional landraces and modern cultivars (C518/2*PBW343) based on various morpho-physiological traits. A total of 175 RILs were selected for this study based on various tolerance indices. The genotype by trait (GT) biplot analysis was applied to data from seven high-yielding RILs grown under irrigated (E1) and rainfed environments (E2). The GGE biplot explained 100% of the total variation for chlorophyll content, grain filling period, peduncle length, water-soluble carbohydrates, grain number, grain yield, and 95.1% for canopy temperature, 94.9% for thousand-grain weight. GT-biplots indicated that the relationships among the studied traits were not consistent across environments, but they facilitated visual genotype comparisons and selection in each environment. RIL 84 and RIL108 were close to the average environment (ideal genotype) for all traits studied except chlorophyll content. A well-performing genotype with great environmental stability is called an "ideal genotype. Among all entries, these genotypes performed well. Therefore, among the traits studied, grain filling period, peduncle length, canopy temperature, water soluble carbohydrates, and 1000 grain weight contributed to grain yield under a stress environment. Furthermore, it may be used as a donor material in breeding programs and QTLs mapping.

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Screening of barley genotypes for drought tolerance based on culm reserves contribution to grain yield

Journal of the Bangladesh Agricultural University ◽

10.3329/jbau.v16i1.36482 ◽

2018 ◽

Vol 16 (1) ◽

pp. 62-66

Author(s):

Md Masudul Karim ◽

Md Amirul Islam ◽

Md Rasel Rana ◽

Md Alamgir Hossain ◽

Md Abdul Kader

Keyword(s):

Drought Stress ◽

Grain Yield ◽

Grain Filling ◽

Water Soluble ◽

Grain Weight ◽

Soluble Carbohydrates ◽

Barley Cultivars ◽

Two Factors ◽

Grain Filling Period ◽

Ripe Stage

Grain filling determines the grain weight, a major component of grain yield in cereals. Grain filling in barley depends on current assimilation and culm reserves. A pot experiment was conducted at the Grilled House, Department of Crop Botany, Bangladesh Agricultural University, Mymensingh during October 2015–May 2016 to study the grain filling patterns and the contributions of culm reserves to grain yield under drought stress. The experiment consisted of two factors—barley cultivars (six cultivars) and drought stress treatments (control and drought stress). Drought stress was imposed by limiting the irrigation during grain filling period. The tillers were sampled at anthesis, milk-ripe and maturity to determine the changes in dry weights of different parts, viz., leaf lamina, culm with sheath, spikes, and grains; and to examine the contribution of culm reserves to grain yield. The result in this experiment revealed that the grain yield was reduced by 5–25% due to drought stress. The reduction in grain yield was attributable to reduce number of grains per spike and lighter grain weight due to the stress. Drought stress drastically reduced the grain filling duration by about 30% and the stress induced early leaf senescence. Photosynthesis rate and leaf greenness were also reduced in stress. The stress altered the contribution of culm reserves, water soluble carbohydrates (WSCs) in culms to grains. At milk ripe stage, accumulation reached its peak. It accumulated 29.0 to 70.0 mg and from 15.8 to 40.6 mg culm−1 in control and stressed plants, respectively. The residual culm WSCs ranged from 3.5 to 11.2 mg and 1.0 to 3.5 mg culm−1 under control and stress conditions, respectively. The highest contribution of culm WSCs to grain yield was observed in BARI barley2 and the lowest was in BARI barley5 both in control and stress condition. Among the cultivars studied, BARI barley2 produced higher yield with the higher contribution of culm reserves to grain yield under the drought stress.J. Bangladesh Agril. Univ. 16(1): 62-66, April 2018

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Genotypic variation in the accumulation of water soluble carbohydrates in wheat

Functional Plant Biology ◽

10.1071/fp12077 ◽

2012 ◽

Vol 39 (7) ◽

pp. 560 ◽

Cited By ~ 15

Author(s):

C. Lynne McIntyre ◽

David Seung ◽

Rosanne E. Casu ◽

Gregory J. Rebetzke ◽

Ray Shorter ◽

...

Keyword(s):

Candidate Genes ◽

Empirical Studies ◽

Genotypic Variation ◽

Grain Filling ◽

Water Soluble ◽

Soluble Carbohydrates ◽

Winter Cereals ◽

Expression Of Genes ◽

Water Soluble Carbohydrates ◽

Selection For

Water-soluble carbohydrates (WSC) stored in the stems and leaf sheaths of winter cereals provide an important source of assimilate for remobilisation during grain-filling. Consequently, WSC are a major contributor to wheat grain yield and grain size in all environments but especially where photosynthesis is compromised as occurs where water is limiting. Breeding programs targeting greater WSC should provide improved varieties with greater and more stable yields in stress environments. To facilitate selection for WSC, genetic and genomic approaches are being used to determine the genetic basis of – and define DNA probes for – marker-aided selection for this important drought-adaptive trait. Empirical studies have identified both WSC concentration and content to be under complex genetic control of many genes. Quantitative trait loci (QTL) for WSC have been identified in several wheat populations with individual QTL explaining small amounts of phenotypic variation, typically of less than 20%. Many of these QTL are common across multiple, genetically-unrelated wheat populations. Evaluation of gene expression in high and low WSC wheat progeny lines from a well characterised wheat population has identified significant differences in expression of genes from different gene categories. For example, high WSC progeny lines have higher levels of expression of genes involved in carbohydrate metabolism and lower levels of expression of genes involved in cell wall and amino acid metabolism than low WSC lines. Genetic mapping reveals several candidate genes co-locating with QTL for WSC. In addition, expression QTL (eQTL) for selected candidate genes co-locate with WSC QTL; co-location of the genes and eQTL with WSC QTL make these genes stronger candidate genes for the WSC trait.

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