High-throughput phenotyping to dissect genotypic differences in safflower for drought tolerance

Drought is one of the most severe and unpredictable abiotic stresses, occurring at any growth stage and affecting crop yields worldwide. Therefore, it is essential to develop drought tolerant varieties to ensure sustainable crop production in an ever-changing climate. High-throughput digital phenotyping technologies in tandem with robust screening methods enable precise and faster selection of genotypes for breeding. To investigate the use of digital imaging to reliably phenotype for drought tolerance, a genetically diverse safflower population was screened under different drought stresses at Agriculture Victoria’s high-throughput, automated phenotyping platform, Plant Phenomics Victoria, Horsham. In the first experiment, four treatments, control (90% field capacity; FC), 40% FC at initial branching, 40% FC at flowering and 50% FC at initial branching and flowering, were applied to assess the performance of four safflower genotypes. Based on these results, drought stress using 50% FC at initial branching and flowering stages was chosen to further screen 200 diverse safflower genotypes. Measured plant traits and dry biomass showed high correlations with derived digital traits including estimated shoot biomass, convex hull area, caliper length and minimum area rectangle, indicating the viability of using digital traits as proxy measures for plant growth. Estimated shoot biomass showed close association having moderately high correlation with drought indices yield index, stress tolerance index, geometric mean productivity, and mean productivity. Diverse genotypes were classified into four clusters of drought tolerance based on their performance (seed yield and digitally estimated shoot biomass) under stress. Overall, results show that rapid and precise image-based, high-throughput phenotyping in controlled environments can be used to effectively differentiate response to drought stress in a large numbers of safflower genotypes.

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Physiological Screening for Drought Tolerance Traits in Vegetable Amaranth (Amaranthus tricolor) Germplasm

Agriculture ◽

10.3390/agriculture11100994 ◽

2021 ◽

Vol 11 (10) ◽

pp. 994

Author(s):

Norain Jamalluddin ◽

Festo J. Massawe ◽

Sean Mayes ◽

Wai Kuan Ho ◽

Ajit Singh ◽

...

Keyword(s):

Drought Stress ◽

Drought Tolerance ◽

Geometric Mean ◽

Tolerance Index ◽

Genotypic Differences ◽

Amaranthus Tricolor ◽

Drought Tolerant ◽

Drought Tolerance Indices ◽

Tolerance Indices ◽

Screening Trials

Amaranth (Amaranthus tricolor), an underutilized climate smart crop, is highly nutritious and possesses diverse drought tolerance traits, making it an ideal crop to thrive in a rapidly changing climate. Despite considerable studies on the growth and physiology of plants subjected to drought stress, a precise trait phenotyping strategy for drought tolerance in vegetable amaranth is still not well documented. In this study, two drought screening trials were carried out on 44 A. tricolor accessions in order to identify potential drought-tolerant A. tricolor germplasm and to discern their physiological responses to drought stress. The findings revealed that a change in stem biomass was most likely the main mechanism of drought adaptation for stress recovery, and dark-adapted quantum yield (Fv/Fm) could be a useful parameter for identifying drought tolerance in amaranth. Three drought tolerance indices: geometric mean productivity (GMP), mean productivity (MP) and stress tolerance index (STI) identified eight drought-tolerant accessions with stable performance across the two screening trials. The highly significant genotypic differences observed in several physiological traits among the amaranth accessions indicate that the amaranth panel used in this study could be a rich source of genetic diversity for breeding purposes for drought tolerance traits.

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High-Throughput Phenotyping Methods for Breeding Drought-Tolerant Crops

International Journal of Molecular Sciences ◽

10.3390/ijms22158266 ◽

2021 ◽

Vol 22 (15) ◽

pp. 8266

Author(s):

Minsu Kim ◽

Chaewon Lee ◽

Subin Hong ◽

Song Lim Kim ◽

Jeong-Ho Baek ◽

...

Keyword(s):

Drought Stress ◽

High Throughput ◽

Large Scale ◽

Crop Yields ◽

Plant Traits ◽

Rapid Development ◽

Plant Responses ◽

Phenotypic Data ◽

Agricultural Technologies ◽

High Throughput Phenotyping

Drought is a main factor limiting crop yields. Modern agricultural technologies such as irrigation systems, ground mulching, and rainwater storage can prevent drought, but these are only temporary solutions. Understanding the physiological, biochemical, and molecular reactions of plants to drought stress is therefore urgent. The recent rapid development of genomics tools has led to an increasing interest in phenomics, i.e., the study of phenotypic plant traits. Among phenomic strategies, high-throughput phenotyping (HTP) is attracting increasing attention as a way to address the bottlenecks of genomic and phenomic studies. HTP provides researchers a non-destructive and non-invasive method yet accurate in analyzing large-scale phenotypic data. This review describes plant responses to drought stress and introduces HTP methods that can detect changes in plant phenotypes in response to drought.

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Discrimination of drought tolerance in a worldwide collection of safflower (Carthamus tinctorius L.) genotypes based on selection indices

Acta agriculturae Slovenica ◽

10.14720/aas.2021.117.1.1656 ◽

2021 ◽

Vol 117 (1) ◽

pp. 1

Author(s):

Pooran GOLKAR ◽

Esmaeil HAMZEH ◽

Seyed Ali Mohammad MIRMOHAMMADY MAIBODY

Keyword(s):

Drought Stress ◽

Drought Tolerance ◽

Geometric Mean ◽

Resistance Index ◽

Stability Index ◽

Carthamus Tinctorius ◽

Tolerance Index ◽

Breeding Programs ◽

Drought Tolerance Indices ◽

Tolerance Indices

Improvement of elite safflower genotypes for drought-tolerance is hampered by a deficiency of effective selection criteria. The present study evaluated 100 genotypes of safflower in terms of their drought tolerance over a period of three years (2016–2018) under both non-stress and drought-stress conditions. The eight drought-tolerance indices of tolerance index (TOL), mean productivity (MP), geometric mean productivity (GMP), stress susceptibility index (SSI), stress tolerance index (STI), yield stability index (YSI), drought resistance index (DI), and harmonic mean (HARM) were calculated based on seed yield under drought (Ys) and non-drought (Yp) conditions. A high genetic variation was found in drought tolerance among the genotypes studied. The MP, GMP, and STI indices were able to discriminate between tolerant and drought-sensitive genotypes. Plots of the first and second principal components identified drought-tolerant genotypes averaged over the three study years. Cluster analysis divided the genotypes into three distinct groups using the drought tolerance indices. Ultimately, eight genotypes (namely, G3, G11, G13, G24, G33, G47, G58, and G61) from different origins were detected as more tolerant to drought stress suitable for use in safflower breeding programs in drought-affected areas. The most tolerant and susceptible genotypes could be exploited to produce mapping populations for drought tolerance breeding programs in safflower.

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Water deficit stress tolerance assessment in barley cultivars using drought tolerance indices

10.21203/rs.3.rs-1088066/v1 ◽

2021 ◽

Author(s):

Md Habib ◽

Md Mannan ◽

Md Karim ◽

Md Miah ◽

Hari Singh

Keyword(s):

Drought Stress ◽

Drought Tolerance ◽

Grain Yield ◽

Stress Tolerance ◽

Water Deficit ◽

Geometric Mean ◽

Research Work ◽

Tolerance Index ◽

Drought Tolerance Indices ◽

Tolerance Indices

Abstract Crop productivity is greatly affected by drought stress. Understanding the drought tolerance capability of the crop varieties available in a country is the foremost consideration for drought adaptation. The objective of this research work was to examine the drought tolerance potentiality of 5 cultivated barley varieties (BARI Barley5, BARI Barley6, BARI Barley7, BARI Barley8 and BARI Barley9) through calculating drought tolerance indices. A completely randomized design (CRD) with three replications was followed in the experiment, where crops were grown under control (80% of FC) and water deficit environment (50% of FC). Stress Tolerance (TOL), Mean Productivity (MP), Geometric Mean Productivity (GMP), Stress Susceptibility Index (SSI), Stress Tolerance Index (STI), Harmonic Mean (HAM), Yield Index (YI) and Yield Stability Index (YSI) were calculated based on grain yield under control and drought conditions. BARI Barley7 and BARI Barley8 were the most tolerant variety and BARI Barley9 considered as susceptible based on TOL and SSI. Drought tolerance indices like MP, HAM, GMP, TOL as well as STI were showed a high correlation with grain yield under both conditions and were recognized as appropriate indices to identify varieties with high grain yield and low sensitivity to drought stress.

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QTL mapping reveals genomic regions for yield based on an incremental tolerance index to drought stress and related agronomic traits in canola

Crop and Pasture Science ◽

10.1071/cp20046 ◽

2020 ◽

Vol 71 (6) ◽

pp. 562

Author(s):

Harsh Raman ◽

Rosy Raman ◽

Ky Mathews ◽

Simon Diffey ◽

Phil Salisbury

Keyword(s):

Drought Stress ◽

Drought Tolerance ◽

Seed Yield ◽

Irrigation Treatment ◽

Shoot Biomass ◽

Doubled Haploid Population ◽

Limiting Factor ◽

Tolerance Index ◽

Flowering Locus ◽

Genomic Regions

Drought stress, especially at the reproductive stage, is a major limiting factor that compromises the productivity and profitability of canola in many regions of the world. Improved genetics for drought tolerance would enable the identification and development of resilient cultivars, resulting in increased canola production. The main objective of the present study was to dissect the genetic basis of seed yield of canola under water-limited conditions. A doubled haploid population derived from a cross between two Australian parental lines, RP04 and Ag-Outback, was evaluated to identify the genetic variation in fractional normalised deviation vegetative index (NDVI), aboveground shoot biomass accumulation, flowering time and plasticity in seed yield under irrigated and rainfed field conditions in two consecutive years. An irrigation treatment was applied at the 50% flowering stage and an incremental drought tolerance index (DTI) was estimated for seed yield. By utilising a genetic linkage map based on 18851 genome-wide DArTseq markers, we identified 25 genomic regions significantly associated with different traits (logarithm of odds (LOD) ≥ 3), accounting for 5.5–22.3% of the genotypic variance. Three significant genomic regions on chromosomes A06, A10 and C04 were associated with DTI for seed yield. Some of the quantitative trait loci (QTL) were localised in the close proximity of candidate genes involved in traits contributing to drought escape and drought avoidance mechanisms, including FLOWERING LOCUS T (FT) and FLOWERING LOCUS C (FLC). Trait-marker associations identified herein can be validated across diverse environments, and the sequence-based markers may be used in a marker assisted selection breeding strategy to enhance drought tolerance in canola breeding germplasm.

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Evaluation and comparison of drought tolerance in some wild diploid populations, tetraploid and hexaploid cultivars of wheat using stress tolerance indices

Acta agriculturae Slovenica ◽

10.14720/aas.2020.115.1.1336 ◽

2020 ◽

Vol 115 (1) ◽

pp. 105

Author(s):

Sara KHOSRAVI ◽

Reza AZIZINEZHAD ◽

Amin BAGHIZADEH ◽

Mahmood MALEKI

Keyword(s):

Drought Stress ◽

Drought Tolerance ◽

Grain Yield ◽

Stress Tolerance ◽

Block Design ◽

Geometric Mean ◽

Tolerance Index ◽

Wheat Genotypes ◽

Drought Tolerance Indices ◽

Tolerance Indices

This study was carried out on grain yield in wheat genotypes with the aim of assessing genetic potential of drought tolerance. The experiment was performed as split plot in the form of randomized complete block design with three replications under normal and drought stress conditions with 32 genotypes. Based on grain yield, and under the condition of non-stress and drought stress, 5 drought tolerance indices are estimated including Tolerance Index (TOL), Stress Tolerance (STI), Mean Productivity (MP), Geometric Mean (GMP) and, Harmonic Mean (HM) for all kinds of genotypes. The analysis of yield correlation and drought tolerance indices in two environments indicated that STI, MP, GMP, HM indices were the most suitable parameters for screening wheat genotypes. Principal components analysis exhibited that the 83 % of first principal component and the 15 % of second one justified the variation of the initial data. Drawing bi-plot diagram declared that Sabalan, Shabrang, Aria, Azar, Azadi, and T2 genotypes were highly functional and resistant to drought stress.

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High-throughput phenotyping reveals differential transpiration behavior within the banana wild relatives highlighting diversity in drought tolerance

10.22541/au.162788270.08316844/v1 ◽

2021 ◽

Author(s):

David Eyland ◽

Nathalie Luchaire ◽

Llorenç Cabrera-Bosquet ◽

Boris Parent ◽

Steven Janssens ◽

...

Keyword(s):

Drought Tolerance ◽

High Throughput ◽

Environmental Conditions ◽

Stomatal Closure ◽

Soil Water Potential ◽

Wild Relatives ◽

Genotypic Differences ◽

Breeding Programs ◽

Drought Avoidance ◽

High Throughput Phenotyping

Crop wild relatives, the closely related species of crops, may harbor potentially important sources of new allelic diversity for (a)biotic tolerance or resistance. However, to date wild diversity is only poorly characterized and evaluated. Banana has a large wild diversity but only a narrow proportion is currently used in breeding programs. The main objective of this work was to evaluate genotype-dependent transpiration responses in relation to the environment. By applying continuous high-throughput phenotyping, we were able to construct genotype-specific transpiration response models in relation to light, VPD and soil water potential. We characterized and evaluated 6 (sub)species and discerned four phenotypic clusters. Significant differences were observed in leaf area, cumulative transpiration and transpiration efficiency. We confirmed a general stomatal-driven ‘isohydric’ drought avoidance behavior, but discovered genotypic differences in the onset and intensity of stomatal closure. We pinpointed crucial genotype specific environmental conditions when drought avoidance mechanisms were initiated and when stress kicked in. Differences between (sub)species were more pronounced under certain environmental conditions, illustrating the need for high-throughput dynamic phenotyping, modelling and validation. We conclude that the banana wild relatives contain useful drought tolerance traits, emphasizing the importance of their conservation and potential for use in breeding programs.

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Evaluation of durum wheat genotypes based on drought tolerance indices under different levels of drought stress

Journal of Agricultural Sciences Belgrade ◽

10.2298/jas1701001m ◽

2017 ◽

Vol 62 (1) ◽

pp. 1-14 ◽

Cited By ~ 1

Author(s):

Reza Mohammadi ◽

Abdolvahab Abdulahi

Keyword(s):

Drought Stress ◽

Drought Tolerance ◽

Durum Wheat ◽

Geometric Mean ◽

Tolerance Index ◽

Wheat Genotypes ◽

Drought Conditions ◽

Drought Tolerance Indices ◽

Tolerance Indices ◽

Different Levels

Objectives of this study were to assess durum wheat genotypes for drought tolerance and to study relationships among different drought tolerance indices under different drought stress conditions. The total of twenty-two durum wheat lines was evaluated in a RCBD experiment with three replications for three cropping seasons (2008-2009; 2009-2010 and 2010-2011). Different drought indices such as tolerance (TOL), mean productivity (MP), mean relative performance (MRP), stress susceptibility index (SSI), modified severity stress index (SSSI), geometric mean productivity (GMP), stress tolerance index (STI), yield stability index (YSI), relative efficiency index (REI) and drought response index (DRI) were determined based on yields under drought and non-drought conditions. The studied genotypes showed considerable variation in performance and tolerated various drought conditions that could be exploited in the durum wheat breeding program. The screening of genotypes for drought tolerance in environments with a greater value of stress intensity (SI) will be more efficient in the grouping of indices and genotype selection. The indices were classified into groups (G1 and G2). The group G1, which consisted of the indices REI, STI, MRP, GMP, DRI and YSI, distinguished genotypes with higher yield in different levels of drought stress. The durum breeding line nos. 1, 11, 10, 13, 8, 9, and 12 were superior based on the group G1 and could be regarded for further evaluation in drought-prone environments.

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Evaluation of Drought Tolerance in Rapeseed Genotypes under Non Stress and Drought Stress Conditions

Notulae Botanicae Horti Agrobotanici Cluj-Napoca ◽

10.15835/nbha3926172 ◽

2011 ◽

Vol 39 (2) ◽

pp. 164 ◽

Cited By ~ 10

Author(s):

Amir Hossein SHIRANI RAD ◽

Abouzar ABBASIAN

Keyword(s):

Drought Stress ◽

Drought Tolerance ◽

Block Design ◽

Geometric Mean ◽

Stability Index ◽

Stress Conditions ◽

Stress Index ◽

Drought Indices ◽

Tolerance Index ◽

Brassica Napus L

Drought is a wide spread problem seriously influencing rapeseed (Brassica napus L.) production, mostly in dryland regions. This study was conducted to determine drought tolerance genotypes with superiority in different stressed environments. Twenty three rapeseed genotypes were tested in a split plot design based on randomized complete block design (RCBD) with four replications in two years (2008- 2009 and 2009-2010) at Seed and Plant Improvement Institute of Karaj, Iran. Seven drought resistance indices include susceptible stress index (SSI), tolerance index (TOL), stress mean productivity (MP), geometric mean productivity (GMP), stress tolerance index (STI), yield index (YI) and yield stability index (YSI) were applied on the basis of seed yield in non stress and drought stress conditions. Based on different drought indices, genotypes ‘Modena’, ‘Geronimo’, ‘Elite’, ‘Syn-4’ and ‘SLM046’ had the best rank with low standard deviation. The results indicated that they have stable yield performance. Bi-plot display and cluster analysis cleared superiority of these genotypes in both years. The synthetic derived cultivars could perform well across all environments with better agronomic performance. Results showed MP, GMP and YI indices were more effective in identifying high yielding cultivars in diverse water scarcity.

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QTL mapping reveals genomic regions for yield based on incremental tolerance index to drought stress and related agronomic traits in canola

10.1101/2020.01.06.896688 ◽

2020 ◽

Author(s):

Harsh Raman ◽

Rosy Raman ◽

Ky Mathews ◽

Simon Diffey ◽

Phil Salisbury

Keyword(s):

Drought Stress ◽

Drought Tolerance ◽

Seed Yield ◽

Irrigation Treatment ◽

Shoot Biomass ◽

Doubled Haploid Population ◽

Limiting Factor ◽

Tolerance Index ◽

Flowering Locus ◽

Genomic Regions

AbstractDrought stress especially at the reproductive stage is a major limiting factor that compromises the productivity and profitability of canola in many regions of the world. Improved genetics for drought tolerance would enable the identification and development of resilient varieties, resulting in increased canola production. The main objective of this study was to dissect the genetic basis of seed yield under water-limited conditions in canola. A doubled haploid population derived from a cross between two Australian parental lines, RP04 and Ag-Outback, was evaluated to identify the genetic variation in fractional normalised deviation vegetative index (NDVI), above ground shoot biomass accumulation, flowering time, and plasticity in seed yield under irrigated and rainfed field conditions in two consecutive years. An irrigation treatment was applied at the 50% flowering stage and an incremental drought tolerance index (DTI) was estimated for seed yield. By utilising a genetic linkage map based on 18,851 genome-wide DArTseq markers, we identified 25 genomic regions significantly associated with different traits (LOD ≥ 3), accounting for 5.5 to 22.3% of the genotypic variance. Three significant genomic regions on chromosome A06, A10 and C04 were associated with DTI for seed yield. Some of the QTL were localised in the close proximity of candidates genes involved in traits contributing to drought escape and drought avoidance mechanisms, including FLOWERING LOCUS T (FT) and FLOWERING LOCUS C (FLC). Trait-marker associations identified herein can be validated across diverse environments, and the sequence based markers may be used in a marker assisted selection breeding strategy to enhance drought tolerance in canola breeding germplasm.

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