Genetic Variation in Salt Tolerance during Seed Germination in a Backcross Inbred Line Population and Advanced Breeding Lines Derived from Upland Cotton × Pima Cotton

Soil and freshwater salinization is increasingly becoming a problem worldwide and has adversely affected plant growth. However, most of the related studies have focused on sodium ion (Na+) stress, with relatively little research on chloride ion (Cl–) stress. Here, we found that upland cotton (Gossypium hirsutum) plants accumulated Cl– and exhibited strong growth inhibition under NaCl or KCl treatment. Then, a chloride channel gene (GhCLCg-1) was cloned from upland cotton. Phylogenetic and sequence analyses indicated that GhCLCg-1 was highly homologous to AtCLCg and also have conserved voltage_CLC and CBS domains. The subcellular localization assay showed that GhCLCg-1 was localized on the vacuolar membrane. Gene expression analyses revealed that the expression of GhCLCg-1 increased rapidly in cotton in response to chloride stress (NaCl or KCl), and the transcript levels increased as the chloride stress intensified. The overexpression of GhCLCg-1 in Arabidopsis thaliana changed the uptake of ions with a decrease of the Na+/K+ ratios in the roots, stems, and leaves, and enhanced salt tolerance. In contrast, silencing GhCLCg-1 in cotton plants increased the Cl– contents in the roots, stems, and leaves and the Na+/K+ ratios in the stems and leaves, resulting in compromised salt tolerance. These results provide important insights into the toxicity of chloride to plants and also indicate that GhCLCg-1 can positively regulates salt tolerance by adjusting ion accumulation in upland cotton.

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Effect of NaCl on seed germination in some Centaurium Hill. Species (Gentianaceae)

Archives of Biological Sciences ◽

10.2298/abs0703227z ◽

2007 ◽

Vol 59 (3) ◽

pp. 227-231 ◽

Cited By ~ 3

Author(s):

S. Zivkovic ◽

M. Devic ◽

B. Filipovic ◽

Z. Giba ◽

D. Grubisic

Keyword(s):

Life History ◽

Salt Tolerance ◽

Seed Germination ◽

Gibberellic Acid ◽

White Light ◽

The Other ◽

Distilled Water ◽

Nacl Concentration ◽

History Of ◽

Species Specific

The influence of high NaCl concentrations on seed germination in both light and darkness was examined in the species Centaurium pulchellum, C. erythraea, C. littorale, C. spicatum, and C. tenuiflorum. Salt tolerance was found to depend on the life history of the seeds. To be specific, seeds of all five species failed to complete germination when exposed to continuous white light if kept all the time in the presence of 100-200 mM and greater NaCl concentrations. However, when after two weeks NaCl was rinsed from the seeds and the seeds were left in distilled water under white light for an additional two weeks, all species completed germination to a certain extent. The percent of germination not only depended on NaCl concentration in the prior medium, but was also species specific. Thus, seeds of C. pulchellum, C. erythraea, and C. littorale completed germination well almost irrespective of the salt concentration previously experienced. On the other hand, seeds of C. tenuiflorum completed germination poorly if NaCl concentrations in the prior media were greater than 200 mM. When seeds after washing were transferred to darkness for an additional 14 days, they failed to complete germination if previously imbibed on media containing NaCl concentrations greater than 400 mM. However, the seeds of all species, even if previously imbibed at 800 mM NaCl, could be induced to complete germination in darkness by 1 mM gibberellic acid. .

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Genetic Variation among and within United States Collard Cultivars and Landraces as Determined by Randomly Amplified Polymorphic DNA Markers

Journal of the American Society for Horticultural Science ◽

10.21273/jashs.121.3.374 ◽

1996 ◽

Vol 121 (3) ◽

pp. 374-379 ◽

Cited By ~ 17

Author(s):

Mark W. Farnham

Keyword(s):

Genetic Variation ◽

Dna Markers ◽

Crop Improvement ◽

Similarity Index ◽

Randomly Amplified Polymorphic Dna ◽

Brussels Sprouts ◽

Breeding Lines ◽

Intrapopulation Variation ◽

Similarity Indices ◽

Systematic Collection

A collection of collard (Brassica oleracea L., Acephala group) germplasm, including 13 cultivars or breeding lines and 5 landraces, was evaluated using randomly amplified polymorphic DNA (RAPD) markers and compared to representatives of kale (Acephala group), cabbage (Capitata group), broccoli (Italica group), Brussels sprouts (Gemmifera group), and cauliflower (Botrytis group). Objectives were to assess genetic variation and relationships among collard and other crop entries, evaluate intrapopulation variation of open-pollinated (OP) collard lines, and determine the potential of collard landraces to provide new B. oleracea genes. Two hundred nine RAPD bands were scored from 18 oligonucleotide decamer primers when collard and other B. oleracea entries were compared. Of these, 147 (70%) were polymorphic and 29 were specific to collard. Similarity indices between collard entries were computed from RAPD data and these ranged from 0.75 to 0.99 with an average of 0.83. Collard entries were most closely related to cabbage (similarity index = 0.83) and Brussels sprouts entries (index = 0.80). Analysis of individuals of an OP cultivar and landrace indicated that intrapopulation genetic variance accounts for as much variation as that observed between populations. RAPD analysis identified collard landraces as unique genotypes and showed them to be sources of unique DNA markers. The systematic collection of collard landraces should enhance diversity of the B. oleracea germplasm pool and provide genes for future crop improvement.

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Pretreatment with H2O2 Alleviates the Negative Impacts of NaCl Stress on Seed Germination of Tartary Buckwheat (Fagopyrum tataricum)

Plants ◽

10.3390/plants10091784 ◽

2021 ◽

Vol 10 (9) ◽

pp. 1784

Author(s):

Xin Yao ◽

Meiliang Zhou ◽

Jingjun Ruan ◽

Yan Peng ◽

Hao Yang ◽

...

Keyword(s):

Superoxide Dismutase ◽

Salt Tolerance ◽

Seed Germination ◽

Superoxide Dismutase Activity ◽

Stress Factors ◽

Tartary Buckwheat ◽

Tolerance Index ◽

Fagopyrum Tataricum ◽

Germination Parameters ◽

H2o2 Pretreatment

Soil salinization is one of the main abiotic stress factors impacting the growth of crops and the agricultural industry today. Thus, we aimed to investigate the effects of H2O2 pretreatment on seed germination in Tartary buckwheat (Fagopyrum tataricum) seeds under salt stress and to evaluate this species’ salt tolerance. Through the preliminary experiment, this study used 50 mmol L−1 NaCl solution to induce seed stress. After soaking for 12 h in different H2O2 concentrations, seeds were laid in Petri dishes with 50 mmol L−1 NaCl for seven days and the germination parameters and physiological indicators were measured to screen the optimal H2O2 pretreatment concentration and the salt tolerance index. Our results indicated that pretreatment with 5–10 mmol L−1 H2O2 was most effective in alleviating NaCl’s impacts on the seeds’ germination parameters. Furthermore, the growth and material accumulation of seedlings was promoted; catalase, superoxide dismutase activity, and proline content were enhanced; and malondialdehyde content was reduced. Principal component analysis and stepwise regression revealed six key indicators that had a significant impact on the salt tolerance characteristics of F. tataricum, namely, germination potential, shoot fresh weight, root surface area, root average diameter, catalase activity, and superoxide dismutase activity.

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The assessment of genetic variation from normal, self and backcross families of a triple test cross of pure-breeding lines in wheat

The Journal of Agricultural Science ◽

10.1017/s0021859600061633 ◽

1986 ◽

Vol 106 (1) ◽

pp. 1-6 ◽

Cited By ~ 1

Author(s):

D. S. Virk ◽

Parminder S. Virk

Keyword(s):

Genetic Variation ◽

Bread Wheat ◽

Weighted Least Squares ◽

Model Fitting ◽

Plant Weight ◽

Breeding Lines ◽

Triple Test Cross ◽

Test Cross ◽

Triple Test ◽

Allelic Interaction

SUMMARYNormal, self and backcross families in a triple test cross were used to investigate the inheritance of number of days from sowing to flowering and dry plant weight for a population of pure-breeding lines of bread wheat (Triticum aestivum L.). Several tests of non-allelic interaction, additive genetic and dominance variances were made that involved triple test cross and single tester analyses. Non-allelic interaction was found to be a component of the genetic variation for both traits. The additive and dominance variances were prevalent for both traits. Alternative estimates of additive genetic and dominance variance components did not differ significantly when tested by a weighted least-squares model fitting procedure. The results are discussed in relation to genetic improvement of bread wheat.

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Genetic diversity and population structure of the rice false smut pathogen Ustilaginoidea virens in Sichuan-Chongqing region

Plant Disease ◽

10.1094/pdis-04-21-0750-re ◽

2021 ◽

Author(s):

Anfei Fang ◽

Zhuangyuan Fu ◽

Zexiong Wang ◽

Yuhang Fu ◽

Yubao Qin ◽

...

Keyword(s):

Genetic Diversity ◽

Population Structure ◽

Genetic Variation ◽

Genetic Recombination ◽

Resistance Breeding ◽

Ustilaginoidea Virens ◽

Breeding Lines ◽

Rice False Smut ◽

Geographical Populations ◽

False Smut

Rice false smut caused by Ustilaginoidea virens is currently one of the most devastating fungal diseases of rice panicles worldwide. In this study, two novel molecular markers derived from SNP-rich genomic DNA fragments and a previously reported molecular marker were used for analyzing the genetic diversity and population structure of 167 U. virens isolates collected from nine areas in Sichuan-Chongqing region, China. A total of 62 haplotypes were identified, and a few haplotypes with high frequency were found and distributed in two to three areas, suggesting gene flow among different geographical populations. All isolates were divided into six genetic groups. The groups Ⅰ and Ⅵ were the largest including 61 and 48 isolates, respectively. The pairwise FST values showed significant genetic differentiation among all compared geographical populations. AMOVA showed that intergroup genetic variation accounted for 40.17% of the total genetic variation, while 59.83% of genetic variation came from intragroup. The UPGMA dendrogram and population structure revealed that the genetic composition of isolates collected from ST (Santai), NC (Nanchong), YC (Yongchuan), and WS (Wansheng) dominated by the same genetic subgroup was different from those collected from other areas. In addition, genetic recombination was found in a few isolates. These findings will help to improve the strategies for rice false smut management and resistance breeding, such as evaluating breeding lines with different isolates or haplotypes at different elevations and landforms.

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