Drought Effects on Growth, Water Content, and Organic Osmoprotectants in Promising Almond Genotypes with Different Drought Tolerance

Abstract Background Almonds ( Prunus amygdalus Batsch, syn. P. dulcis (Mill.) DA Webb) is a valuable nut crops species that is widely is cultivated in arid and semi-arid regions of Iran, due to drought tolerance and dehydration under drought stress. Almonds show physiological adaptations for survival in drought stress conditions, but the degree Drought adaptation varies between cultivars. However, to date, its morphological and physiological responses to drought, and the underlying mechanisms are not well understood. This study was aimed to investigate the morphological and physiological changes of almond genotypes under drought stress. almond genotypes were planted in pots and subjected to four levels of soil water treatments: above 80% (control), 60% (light stress), and 40% (severe stress) of field capacity. Results Within the total stress period (0–30 days), almond genotypes grew rapidly in the light stress, whereas severe stress had a negative impact on growth. So that, in this study, 10 selected almond genotypes using some morphological traits such as: plant height, trunk diameter at the top of the graft, new branch growth length, leaf yellowness and some physiological indicators under drought stress conditions such as Chlorophyll index was evaluated based on SPAD criterion, relative leaf water content, measurement of chlorophyll fluorescence and Organic Osmoprotectants to identify drought-resistant and sensitive genotypes under drought stress conditions. Among the selected genotypes studied, genotype A-7-100 was the most resistant and genotype A-124-1 was the most sensitive to drought stress. Conclusions Our results show that almond genotypes adapt to drought mainly by avoidance mechanisms, and its morphological and physiological characteristics are inhibited under severe stress, However, the degree of drought adaptation varies between different cultivars. These findings might help limited water resources to be fully used for increased the percentage of kernel and finally increased the growth and yield of plants under water stress.

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Pengaruh biostimulan terhadap toleransi kekeringan dan pertumbuhan tanaman tebu varietas Kidang Kencana di rumah kaca (Effect of biostimulants on drought tolerance and growth of sugarcane var. Kidang Kencana at green house)

E-Journal Menara Perkebunan ◽

10.22302/iribb.jur.mp.v1i1.287 ◽

2018 ◽

Vol 86 (1) ◽

Author(s):

Dian Mutiara AMANAH ◽

Soekarno Mismana PUTRA

Keyword(s):

Drought Stress ◽

Humic Acid ◽

Drought Tolerance ◽

Plant Height ◽

Vegetative Growth ◽

Sugar Yield ◽

Stress Conditions ◽

Growth And Yield ◽

Segment Number ◽

Increasing Demand

Increasing productivity and sugar yield of sugarcane are required to meet the increasing demand for sugar. Biostimulants application is one of the effort to increase the productivity and rendement of sugar, especially at drought stress conditions. The purpose of this study was to determine the effect of biostimulants on the performance of sugarcane var. Kidang Kencana known susceptible to drought stress. The research was conducted in the greenhouse with several biostimulant treatments i.e. P0: Control, P1: Citorin-R, P2: Citorin-R and Citorin-S (1x spray) P3: Citorin-R and Citorin -S (2x spray), P4: Citorin-R, Citorin-S (1x spray) and Humic Acid, P5: Citorin-R, Citorin-S (1x spray), Humic Acid and Mycorrhiza, P6: Citorin-R, Citorin-S (2x spray), Humic Acid and Mycorrhiza. All treatments were subjected with drought stress started from 4 months after planting. The biostimulant treatments resulted in better growth and yield on treated-biostimulan compared to these of control. The best treatment for the vegetative growth and the productive parameters was P6. The plant height, stems diameter, segment number, weight, and sap volume at P6 were respectively 32.2%, 5.5%, 24.0%, 53.2% and 44.7% higher than the control. The best treatment for the sugar yield was P5 and the productivity parameters was P6 respectively, 42.5% and 70.5% higher than the control. The best treatments contained Citorin biostimulant. Humic Acid and Mycorrhiza which increased growth and sugar yield of Kidang Kencana sugarcane at drought stress conditions.[Keywords: drought stress Kidang Kencana variety, plant biostimulant, productivity, sugar yield]. AbstrakPeningkatan produktivitas dan rendemen gula tanaman tebu diperlukan untuk memenuhi kebutuhan gula yang terus meningkat. Aplikasi biostimulan merupakan salah satu upaya untuk meningkatkan produktivitas dan rendemen gula khususnya pada kondisi tercekam kekeringan. Tujuan dari penelitian ini adalah untuk mengetahui pengaruh pemberian beberapa produk biostimulan terhadap produktivitas tanaman tebu varietas Kidang Kencana yang rentan cekaman kekeringan. Penelitian dilakukan di rumah kaca dengan perlakuan beberapa perlakuan biostimulan pada tanaman tebu, yaitu P0: Kontrol, P1: Citorin-R, P2: Citorin-R dan Citorin-S (1x semprot) P3: Citorin-R dan Citorin-S (2x semprot), P4: Citorin-R, Citorin-S (1x semprot) dan Asam Humat, P5: Citorin-R, Citorin-S (1x semprot), Asam Humat dan Mikoriza, P6: Citorin-R, Citorin-S (2x semprot), Asam Humat dan Mikoriza. Seluruh perlakuan diberi kondisi cekaman kekeringan pada 4 bulan setelah tanam. Perlakuan biostimulan memberikan pengaruh serta hasil yang lebih baik dibandingkan dengan kontrol baik fase vegetatif maupun produktif. Perlakuan terbaik selama fase vegetatif hingga 5 bulan setelah tanam adalah P6. Tinggi batang panen, diameter batang panen, jumlah ruas batang, bobot batang dan volume nira pada P6 meningkat 32,2%, 5,5%, 24,0%, 53,2% dan 44,7% lebih tinggi dibandingkan dengan kontrol. Perlakuan terbaik untuk parameter rendemen gula adalah P5 dan produktivitas gula adalah P6, masing-masing 42,5% dan 70,5% lebih tinggi dibandingkan kontrol. Perlakuan terbaik tersebut mengandung komponen biostimulan yaitu Citorin, Asam Humat dan Mikoriza yang dapat meningkatkan pertumbuhan dan rendemen gula tanaman tebu Kidang Kencana pada kondisi cekaman kekeringan. [Kata kunci: cekaman kekeringan, varietas Kidang Kencana, biostimulan tanaman, produktivitas, rendemen gula].

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Development of a diurnal dehydration index for spring barley phenotyping

Functional Plant Biology ◽

10.1071/fp14069 ◽

2014 ◽

Vol 41 (12) ◽

pp. 1249 ◽

Cited By ~ 10

Author(s):

Pablo Rischbeck ◽

Peter Baresel ◽

Salah Elsayed ◽

Bodo Mistele ◽

Urs Schmidhalter

Keyword(s):

Drought Stress ◽

Drought Tolerance ◽

Water Content ◽

Water Status ◽

Spring Barley ◽

Leaf Water ◽

Leaf Angle ◽

Leaf Water Content ◽

Diurnal Changes ◽

Angle Distribution

Spectral and thermal assessments may enable the precise, high-throughput and low-cost characterisation of traits linked to drought tolerance. However, spectral and thermal measurements of the canopy water status are influenced by the crops’ soil coverage, the size of the biomass and other properties such as the leaf angle distribution. The aim of this study was to develop a referenced spectral method that would be minimally influenced by potentially perturbing factors for retrieving the water status of differing cultivars. Sixteen spring barley cultivars were grown in field trials under imposed drought stress, natural drought stress and irrigated conditions. The relative leaf water content of barley plants declines diurnally from pre-dawn until the afternoon, and other plant traits such as the biomass change little throughout the day. As an indicator of the current drought stress, pre-dawn and afternoon values of the relative leaf water content were assessed spectrally. Diurnal changes in reflectance are only slightly influenced by other perturbing factors. A new spectral index (diurnal dehydration index) was developed by using the wavelengths 730 and 457 nm collected from an active spectrometer. This index allowed the differentiation of the drought tolerance of barley plants. The diurnal dehydration index was significantly related to final biomass, grain yield and harvest index and significantly different between cultivars. Compared with other indices, the diurnal dehydration index offered a higher stability in retrieving the water status of barley plants. Due to its diurnal assessment, the index was barely influenced by the differences in cultivars biomass at the time of measurement. It may represent a valuable tool for assessing the water status or drought tolerance in breeding nurseries.

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Influence of biostimulants and media compositions on growth and yield of Capsicum annuum L. under drought stress conditions

Advances in Horticultural Science ◽

10.36253/ahsc-8354 ◽

2021 ◽

Vol 35 (2) ◽

Author(s):

Budiyati Ichwan ◽

Eliyanti Eliyanti ◽

Zulkarnain Zulkarnain

Keyword(s):

Drought Stress ◽

Water Content ◽

Soil Water ◽

Soil Water Content ◽

Rice Husk ◽

Field Capacity ◽

Medium Composition ◽

Stress Conditions ◽

Growth And Yield ◽

Chlorophyll Contents

The study was conducted at the Teaching and Research Farm of Agricultural Faculty, University of Jambi, Indonesia, from April through to September 2019. The aim of this study was to investigate the effect of biostimulants and media compositions on the growth and yield of chili pepper during restricted soil water content. The study was arranged in a split plot design with 3 replicates (groups). Different types of biostimulants (Citorin®, Hantu®, and a control) were designated as main plot, whereas media compositions (2:2:1, 2:1:1, 1:2:1 and 1:1:2) made of soil+trichocompost+rice husk charcoal were employed as sub plot. At the time of transplanting, soil water content was set to approximately 75% of field capacity to create stress conditions. The results showed that the proper choice of biostimulant and medium composition could increase nutrient status, total sugar and chlorophyll contents, and reduce proline level in plants grown under restricted water availability. Citorin® application on chili plants grown on organic media (soil+trichocompost+rice husk charcoal) with ratio of 2:1:1 could be recommended to support plant growth and production under drought stress conditions.

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Quantitative Response of Maize Vcmax25 to Persistent Drought Stress at Different Growth Stages

Water ◽

10.3390/w13141971 ◽

2021 ◽

Vol 13 (14) ◽

pp. 1971

Author(s):

Xingyang Song ◽

Guangsheng Zhou ◽

Qijin He ◽

Huailin Zhou

Keyword(s):

Drought Stress ◽

Early Warning Systems ◽

Growth And Yield ◽

Leaf Water Content ◽

Growth Stages ◽

Leaf Stage ◽

Maximum Value ◽

Maize Varieties ◽

Persistent Drought ◽

Different Growth Stages

Drought stress has adverse effects on crop growth and yield, and its identification and monitoring play vital roles in precision crop water management. Accurately evaluating the effect of drought stress on crop photosynthetic capacity can provide a basis for decisions related to crop drought stress identification and monitoring as well as drought stress resistance and avoidance. In this study, the effects of different degrees of persistent drought in different growth stages (3rd leaf stage, 7th leaf stage and jointing stage) on the maximum carboxylation rate at a reference temperature of 25 °C (Vcmax25) of the first fully expanded leaf and its relationship to the leaf water content (LWC) were studied in a field experiment from 2013 to 2015. The results indicated that the LWC decreased continuously as drought stress continued and that the LWC decreased faster in the treatment with more irrigation. Vcmax25 showed a decreasing trend as the drought progressed but had no clear relationship to the growth stage in which the persistent drought occurred. Vcmax25 showed a significantly parabolic relationship (R2 = 0.701, p < 0.001) with the LWC, but the different degrees of persistent drought stress occurring in different growth stages had no distinct effect on the LWC values when Vcmax25 reached its maximum value or zero. The findings of this study also suggested that the LWC was 82.5 ± 0.5% when Vcmax25 reached its maximum value (42.6 ± 3.6 μmol m−2 s−1) and 67.6 ± 1.2% (extreme drought) when Vcmax25 reached zero. These findings will help to improve crop drought management and will be an important reference for crop drought identification, classification and monitoring as well as for the development of drought monitoring and early warning systems for other crops or maize varieties.

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Genetic Diversity of Selected Rice Genotypes under Water Stress Conditions

Plants ◽

10.3390/plants10010027 ◽

2020 ◽

Vol 10 (1) ◽

pp. 27

Author(s):

Mahmoud M. Gaballah ◽

Azza M. Metwally ◽

Milan Skalicky ◽

Mohamed M. Hassan ◽

Marian Brestic ◽

...

Keyword(s):

Genetic Diversity ◽

Water Stress ◽

Drought Stress ◽

Drought Tolerance ◽

Ssr Markers ◽

Similarity Index ◽

Stress Conditions ◽

Yield Potential ◽

Drought Tolerant ◽

Rice Genotypes

Drought is the most challenging abiotic stress for rice production in the world. Thus, developing new rice genotype tolerance to water scarcity is one of the best strategies to achieve and maximize high yield potential with water savings. The study aims to characterize 16 rice genotypes for grain and agronomic parameters under normal and drought stress conditions, and genetic differentiation, by determining specific DNA markers related to drought tolerance using Simple Sequence Repeats (SSR) markers and grouping cultivars, establishing their genetic relationship for different traits. The experiment was conducted under irrigated (normal) and water stress conditions. Mean squares due to genotype × environment interactions were highly significant for major traits. For the number of panicles/plants, the genotypes Giza179, IET1444, Hybrid1, and Hybrid2 showed the maximum mean values. The required sterility percentage values were produced by genotypes IET1444, Giza178, Hybrid2, and Giza179, while, Sakha101, Giza179, Hybrid1, and Hybrid2 achieved the highest values of grain yield/plant. The genotypes Giza178, Giza179, Hybrid1, and Hybrid2, produced maximum values for water use efficiency. The effective number of alleles per locus ranged from 1.20 alleles to 3.0 alleles with an average of 1.28 alleles, and the He values for all SSR markers used varied from 0.94 to 1.00 with an average of 0.98. The polymorphic information content (PIC) values for the SSR were varied from 0.83 to 0.99, with an average of 0.95 along with a highly significant correlation between PIC values and the number of amplified alleles detected per locus. The highest similarity coefficient between Giza181 and Giza182 (Indica type) was observed and are susceptible to drought stress. High similarity percentage between the genotypes (japonica type; Sakha104 with Sakha102 and Sakha106 (0.45), Sakha101 with Sakha102 and Sakha106 (0.40), Sakha105 with Hybrid1 (0.40), Hybrid1 with Giza178 (0.40) and GZ1368-S-5-4 with Giza181 (0.40)) was also observed, which are also susceptible to drought stress. All genotypes are grouped into two major clusters in the dendrogram at 66% similarity based on Jaccard’s similarity index. The first cluster (A) was divided into two minor groups A1 and A2, in which A1 had two groups A1-1 and A1-2, containing drought-tolerant genotypes like IET1444, GZ1386-S-5-4 and Hybrid1. On the other hand, the A1-2 cluster divided into A1-2-1 containing Hybrid2 genotype and A1-2-2 containing Giza179 and Giza178 at coefficient 0.91, showing moderate tolerance to drought stress. The genotypes GZ1368-S-5-4, IET1444, Giza 178, and Giza179, could be included as appropriate materials for developing a drought-tolerant variety breeding program. Genetic diversity to grow new rice cultivars that combine drought tolerance with high grain yields is essential to maintaining food security.

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Accumulation of Silicon and Changes in Water Balance under Drought Stress in Brassica napus var. napus L.

Plants ◽

10.3390/plants10020280 ◽

2021 ◽

Vol 10 (2) ◽

pp. 280

Author(s):

Diana Saja-Garbarz ◽

Agnieszka Ostrowska ◽

Katarzyna Kaczanowska ◽

Franciszek Janowiak

Keyword(s):

Abscisic Acid ◽

Drought Stress ◽

Stomatal Conductance ◽

Water Balance ◽

Water Content ◽

Oilseed Rape ◽

Potential Evapotranspiration ◽

Leaf Water Content ◽

Optimal Conditions ◽

Abscisic Acid Level

The aim of this study was to investigate the accumulation of silicon in oilseed rape and to characterize the changes in chosen water balance parameters in response to drought. The following parameters were estimated: water content, osmotic and water potential, evapotranspiration, stomatal conductance and abscisic acid level under optimal and drought conditions. It was shown that oilseed rape plants accumulate silicon after its supplementation to the soil, both in the case of silicon alone and silicon together with iron. It was revealed that silicon (without iron) helps maintain constant water content under optimal conditions. While no silicon influence on osmotic regulation was observed, a transpiration decrease was detected under optimal conditions after silicon application. Under drought, a reduction in stomatal conductance was observed, but it was similar for all plants. The decrease in leaf water content under drought was accompanied by a significant increase in abscisic acid content in leaves of control plants and those treated with silicon together with iron. To sum up, under certain conditions, silicon is accumulated even in non-accumulator species, such as oilseed rape, and presumably improves water uptake under drought stress.

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Possible involvement of phosphoenolpyruvate carboxylase and NAD-malic enzyme in response to drought stress. A case study: a succulent nature of the C4-NAD-ME type desert plant, Salsola lanata (Chenopodiaceae)

Functional Plant Biology ◽

10.1071/fp16430 ◽

2017 ◽

Vol 44 (12) ◽

pp. 1219

Author(s):

Zhibin Wen ◽

Mingli Zhang

Keyword(s):

Enzyme Activity ◽

Drought Stress ◽

Phosphoenolpyruvate Carboxylase ◽

Malic Enzyme ◽

C4 Plants ◽

Leaf Water Content ◽

Transcriptional Level ◽

Desert Plant ◽

Severe Stress ◽

Real Time Quantitative Pcr

The co-ordination between the primary carboxylating enzyme phosphoenolpyruvate carboxylase (PEPC) and the further decarboxylating enzymes is crucial to the efficiency of the CO2-concentrating mechanism in C4 plants, and investigations on more types of C4 plants are needed to fully understand their adaptation mechanisms. In this study we investigated the effect of drought on carboxylating enzyme PEPC, and the further decarboxylating NAD-malic enzyme (NAD-ME) of Salsola lanata Pall. (Chenopodiaceae) – an annual succulent C4-NAD-ME subtype desert plant. We investigated enzyme activity at the transcriptional level with real-time quantitative PCR and at the translational level by immunochemical methods, and compared S. lanata with other forms of studied C4 plants under drought stress. Results showed that only severe stress limited PEPC enzyme activity (at pH 8.0) of S. lanata significantly. Considering that PEPC enzyme activity (at pH 8.0) was not significantly affected by phosphorylation, the decrease of PEPC enzyme activity (at pH 8.0) of S. lanata under severe stress may be related with decreased PEPC mRNA. The suggestion of increased phosphorylation of the PEPC enzyme in plants under moderate stress was supported by the ratio of PEPC enzyme activity at pH 7.3/8.0, as PEPC enzyme is inhibited by L-malate and the evidence of the 50% inhibiting concentration of L-malate. NAD-ME activity decreased significantly under moderate and severe stress, and coincided with a change of leaf water content rather than the amount of α-NAD-ME mRNA and protein. Leaf dehydration may cause the decrease of NAD-ME activity under water stress. Compared with other C4 plants, the activities of PEPC and NAD-ME of S. lanata under drought stress showed distinct features.

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Identification of Two Novel Wheat Drought Tolerance-Related Proteins by Comparative Proteomic Analysis Combined with Virus-Induced Gene Silencing

International Journal of Molecular Sciences ◽

10.3390/ijms19124020 ◽

2018 ◽

Vol 19 (12) ◽

pp. 4020 ◽

Cited By ~ 8

Author(s):

Xinbo Wang ◽

Yanhua Xu ◽

Jingjing Li ◽

Yongzhe Ren ◽

Zhiqiang Wang ◽

...

Keyword(s):

Drought Stress ◽

Drought Tolerance ◽

Gene Silencing ◽

Proteomic Analysis ◽

Crop Yields ◽

Stress Conditions ◽

Virus Induced Gene Silencing ◽

Knock Down ◽

Comparative Proteomic Analysis ◽

Related Proteins

Drought is a major adversity that limits crop yields. Further exploration of wheat drought tolerance-related genes is critical for the genetic improvement of drought tolerance in this crop. Here, comparative proteomic analysis of two wheat varieties, XN979 and LA379, with contrasting drought tolerance was conducted to screen for drought tolerance-related proteins/genes. Virus-induced gene silencing (VIGS) technology was used to verify the functions of candidate proteins. A total of 335 differentially abundant proteins (DAPs) were exclusively identified in the drought-tolerant variety XN979. Most DAPs were mainly involved in photosynthesis, carbon fixation, glyoxylate and dicarboxylate metabolism, and several other pathways. Two DAPs (W5DYH0 and W5ERN8), dubbed TaDrSR1 and TaDrSR2, respectively, were selected for further functional analysis using VIGS. The relative electrolyte leakage rate and malonaldehyde content increased significantly, while the relative water content and proline content significantly decreased in the TaDrSR1- and TaDrSR2-knock-down plants compared to that in non-knocked-down plants under drought stress conditions. TaDrSR1- and TaDrSR2-knock-down plants exhibited more severe drooping and wilting phenotypes than non-knocked-down plants under drought stress conditions, suggesting that the former were more sensitive to drought stress. These results indicate that TaDrSR1 and TaDrSR2 potentially play vital roles in conferring drought tolerance in common wheat.

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Methionine-induced regulation of growth, secondary metabolites and oxidative defense system in sunflower (Helianthus annuus L.) plants subjected to water deficit stress

PLoS ONE ◽

10.1371/journal.pone.0259585 ◽

2021 ◽

Vol 16 (12) ◽

pp. e0259585

Author(s):

Gull Mehak ◽

Nudrat Aisha Akram ◽

Muhammad Ashraf ◽

Prashant Kaushik ◽

Mohamed A. El-Sheikh ◽

...

Keyword(s):

Drought Stress ◽

Helianthus Annuus ◽

Water Deficit ◽

Soluble Sugars ◽

Foliar Spray ◽

Shoot Length ◽

Stress Conditions ◽

Growth And Yield ◽

Water Deficit Stress ◽

Growth Stages

Optimum water availability at different growth stages is one the major prerequisites of best growth and yield production of plants. Exogenous application of plant growth regulators considered effective for normal functioning of plants under water-deficit conditions. A study was conducted to examine the influence of exogenously applied L-methionine on sunflower (Helianthus annuus L.) plants grown under water-deficit conditions. Twenty-five-day old seedlings of four sunflower cultivars, FH331, FH572, FH652 and FH623 were exposed to control (100% F.C.) and drought stress (60% F.C.) conditions. After 30-day of drought stress, L-methionine (Met; 20 mg/L) was applied as a foliar spray to control and drought stressed plants. Water deficit stress significantly reduced shoot fresh and dry weights shoot and root lengths, and chlorophyll a content in all four cultivars. While a significant increase was observed due to water deficiency in relative membrane permeability (RMP), malondialdehyde (MDA), total soluble proteins (TSP), total soluble sugars (TSS), ascorbic acid (AsA) and activity of peroxidase (POD). Although, exogenously applied Met was effective in decreasing RMP, MDA and H2O2 contents, it increased the shoot fresh weight, shoot length, chlorophyll a, chlorophyll a/b ratio, proline contents and the activities of SOD, POD and CAT enzymes in all four cultivars under water deficit stress. No change in AsA and total phenolics was observed due to foliar-applied Met under water stress conditions. Of all sunflower cultivars, cv. FH-572 was the highest and cv. FH-652 the lowest of all four cultivars in shoot fresh and dry weights as well as shoot length under drought stress conditions. Overall, foliar applied L-methionine was effective in improving the drought stress tolerance of sunflower plants that was found to be positively associated with Met induced improved growth attributes and reduced RMP, MDA and H2O2 contents under water deficit conditions.

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Heritability and mode of gene action determination for grain filling rate and relative water content in hexaploid wheat

Genetika ◽

10.2298/gensr1201025g ◽

2012 ◽

Vol 44 (1) ◽

pp. 25-32 ◽

Cited By ~ 3

Author(s):

Ahmad Golparvar

Keyword(s):

Drought Stress ◽

Water Content ◽

Relative Water Content ◽

Stress Condition ◽

Gene Action ◽

Grain Filling ◽

Stress Conditions ◽

Filling Rate ◽

Grain Filling Rate ◽

Relative Water

Mode of gene action, heritability and determination of the effective breeding strategy for improvement of physiological and traits specifically in drought stress conditions is very important. Therefore, this study was conducted by using two drought susceptible and tolerant wheat cultivars. Cultivars Sakha8 (tolerant) and Pishtaz (susceptible) as parents along with F1, F2, BC1 and BC2 generations were sown in a randomized complete block design with three replications in drought stress conditions. Results of analysis of variance indicated significant difference between generations as well as degree of dominance revealed over-dominance for the both traits. Fitting simple additive-dominance model designated that this model was not able to account for changes of traits relative water content and mean of grain filling rate. It was revealed that m-d-h-i-j model for relative water content and m-d-h-i model for mean of grain filling rate are the best models. Estimation of heritability and mode of gene action indicated that selection for improvement of traits studied in stress condition and specifically in early generations have medium genetic gain. In conclusion, grain filling rate is better than relative water content as indirect selection criteria to improve plant grain yield in drought stress condition.

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