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The purpose of this study was to determine the agro-morphological, physiological, and transcriptional characteristics of ethyl methane sulfonate (EMS)-mutagenized M3 alfalfa (Medicago sativa L.) mutants grown for 24 days under water deficit conditions following the first cutting at the blooming bud stage. Drought stress generally reduced all agro-morphological parameters measured. Cutting stress significantly reduced total chlorophyll contents of all genotypes, with the exception of mutant X20. Significant changes occurred in the levels of ascorbate peroxidase (APX), lipid peroxidation (TBARS), glutathione reductase (GR), superoxide dismutase (SOD) and crude protein levels. Drought stress considerably elevated GR levels in irrigated control (C1) and unirrigated control (C2) plants. In contrast to the other genotypes studied, mutant X20's crude protein level increased significantly after the first cutting under 24 days of water deficit conditions, compared to the level found before cutting. The expression profiles of Medicago truncatula Response to Desiccation 2 (MtRD2) and Medicago sativa proline dehydrogenase (MsProDH) genes differed based on the plant genotype and duration of drought stress. Drought stress increased MsProDH gene expression in X20, X50, and C2 plants by 4.57, 14.8, and 20.65 times, respectively. The findings of the expression study indicated that the MtRD2 gene may play a key role in stress reduction rather than drought stress per se. The results of this study revealed that cutting and drought are two independent stress variables that should be evaluated separately when evaluating genotype response to both irrigated and unirrigated growing environments in alfalfa. [ABSTRACT FROM AUTHOR]

Background: Einkorn wheat is one of the first primary genetic resources for discovery of new alleles related to biotic and abiotic stress tolerances for further genetic improvements while it became more popular especially for its native grain status as healthy food resources. Therefore, this study aims to determine germination parameters of 32 local einkorn (Triticum monococcum) genotypes collected from Kastamonu and its vicinity, Turkey under drought stress conditions, and to reveal the genetic relationship of those genotypes based on drought related gene targeted functional markers (GTFMs). Methods and results: Germination test was conducted at 20 ± 0.5 °C in darkness with randomized complete block design with 4 replications. Seeds placed on double filter papers in a covered glass petri dishes (80 × 15 mm) were treated with polyethylene glycol (PEG6000) with a -0.23 MPa. The final germination percentages (FGPs), speed and span of germination parameters were determined. Drought stress severely worsened all germination parameters measured. The genotypes SG24 and SG12 were the most drought tolerant and sensitive genotypes based on 21.1% and 64.8% of reduction rates in FGPs, respectively. Twelve GTFMs produced a total of 32 bands and 26 of them were polymorphic. The mean polymorphism ratio of the markers and average band per marker were determined as 86.31% and 2.66, respectively. The highest polymorphism information content (PIC) was obtained from AIB1 gene marker (0.875). Conclusions: This study revealed that there was a significant genetic variation for drought tolerance levels of local einkorn wheat genotypes at germination stage and drought related GTFMs can be used not only to reveal genetic variation but also to distinguish the drought tolerant genotypes. [ABSTRACT FROM AUTHOR]

The objectives of this study were to determine drought tolerant novel mutant of alfalfa (Medicago sativa L.) genotypes by screening EMS mutagenized 340675 M3 seeds at germination stages in the presence of osmotic stress of 35% PEG6000. Root growth assay provided several drought tolerant candidate mutants. Of those, 4 mutants were further evaluated at water deficit conditions applied for 24 days after the first cutting at flowering bud stage. The results revealed that mutants determined as drought tolerant at germination stage were also tolerant to water deficit conditions. Protein content and superoxide dismutase values were found to be higher in all mutants than controls. Ascorbate peroxides, glutton reductase and lipid peroxidase values varied based on the mutant genotype and duration of drought stress. Drought stress significantly changed transcriptional levels of MtP5CS, MtDehyd, MseIF-2, MtRD2 and MsNAC genes. These results indicated that in vitro screening of alfalfa mutant seeds for osmatic tolerance at germination and early seedling growth stages was successfully able to determine the drought tolerant alfalfa mutants which were also tolerant to water deficit conditions after the first cutting at flowering bud stage. [ABSTRACT FROM AUTHOR]

The aim of this study was to make morphological and molecular characterization of tall wheatgrass (Thinopyrum ponticum) accessions naturally found in Canakkale flora, Turkey. The seeds collected from 24 different locations in Canakkale vicinity were planted in the nursery field to determine thirteen morphological parameters. Twelve universal rice primers (URPs) were used to reveal genetic relationship among the accessions while ploidy analysis was done based on the nuclear DNA content of plants determined by Flow cytometer. Fluorescence in situ hybridization (FISH) method was used to determine 5S and 45S rDNA distributions on mitotic chromosomes. The agro-morphological data showed significant variation among the accessions for all parameters measured, except the number of nodes per plant. Twelve URP primers produced 73 alleles in total and 63 of those were polymorphic. The highest polymorphism information content value was obtained from URP 17R with 0.82. The first three components of Eigen values in PCA analysis explained 41.1% of total variation. The 2C nuclear DNA contents of the accessions ranged from 41.17 to 45.49 pg. All the accessions were determined as decaploid with 2n = 70 chromosomes. FISH analysis provided 18–20 interstial 5S rDNA and 12–14 terminal 45S rDNA loci. The results concluded that tall wheatgrass accessions used in this study contain a significant variation in morphological traits and PCR-based DNA polymorphism which could be used as a new genetic resource in breeding programs of tall wheatgrass and wheat improvement for intra- and intergeneric crosses. [ABSTRACT FROM AUTHOR]

This study was initiated to reveal genetic relationship of 25 tef (Eragrostis tef (Zucc.) accessions by using 10 SSR markers and to determine DNA content variation by using flow cytometer analysis. Ten markers produced a total of 18 alleles and 11 of those were polymorphic. The mean polymorphism rate was 66.6%. The highest polymorphism information content value was obtained from marker CNLTs370 with 0.69 while markers CNTLs11 and CNTLs133 produced monomorphic bands only. UPGMA analysis divided 25 tef genotypes into three main clades. The accessions PI193511 and PI195934 were distinctly separated from the others. No ploidy differences were determined among the 25 tef accessions. 2C mean nuclear DNA content ranged from 1.406 pg to 1.510 with mean of 1.460 pg. The results of this study indicated that SSR markers successfully determined genetic relationship of 25 tef accession although they had a low rate of polymorphism. This study also revealed that available tef related SSR markers should be optimized before use and their efficiency may vary based on tef genotypes or accessions used. [ABSTRACT FROM AUTHOR]