scholarly journals Identification and fine mapping of qGR6.2, a novel locus controlling rice seed germination under salt stress

2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Peng Zeng ◽  
Peiwen Zhu ◽  
Luofeng Qian ◽  
Xumei Qian ◽  
Yuxin Mi ◽  
...  

Abstract Background Rice growth is frequently affected by salinity. When exposed to high salinity, rice seed germination and seedling establishment are significantly inhibited. With the promotion of direct-seeding in Asia, improving rice seed germination under salt stress is crucial for breeding. Results In this study, an indica landrace Wujiaozhan (WJZ) was identified with high germinability under salt stress. A BC1F2 population derived from the crossing WJZ/Nip (japonica, Nipponbare)//Nip, was used to quantitative trait loci (QTL) mapping for the seed germination rate (GR) and germination index (GI) under H2O and 300 mM NaCl conditions. A total of 13 QTLs were identified, i.e. ten QTLs under H2O conditions and nine QTLs under salt conditions. Six QTLs, qGR6.1, qGR8.1, qGR8.2, qGR10.1, qGR10.2 and qGI10.1 were simultaneously identified under two conditions. Under salt conditions, three QTLs, qGR6.2, qGR10.1 and qGR10.2 for GR were identified at different time points during seed germination, which shared the same chromosomal region with qGI6.2, qGI10.1 and qGI10.2 for GI respectively. The qGR6.2 accounted for more than 20% of phenotypic variation under salt stress, as the major effective QTL. Furthermore, qGR6.2 was verified via the BC2F2 population and narrowed to a 65.9-kb region with eleven candidate genes predicted. Based on the microarray database, five candidate genes were found with high transcript abundances at the seed germination stage, of which LOC_Os06g10650 and LOC_Os06g10710 were differentially expressed after seed imbibition. RT-qPCR results showed the expression of LOC_Os06g10650 was significantly up-regulated in two parents with higher levels in WJZ than Nip during seed germination under salt conditions. Taken together, it suggests that LOC_Os06g10650, encoding tyrosine phosphatase family protein, might be the causal candidate gene for qGR6.2. Conclusions In this study, we identified 13 QTLs from a landrace WJZ that confer seed germination traits under H2O and salt conditions. A major salt-tolerance-specific QTL qGR6.2 was fine mapped to a 65.9-kb region. Our results provide information on the genetic basis of improving rice seed germination under salt stress by marker-assisted selection (MAS).

2020 ◽  
Author(s):  
Peng Zeng ◽  
Peiwen Zhu ◽  
Luofeng Qian ◽  
Xumei Qian ◽  
Yuxin Mi ◽  
...  

Abstract Background Rice growth is frequently affected by salinity. When rice plants are exposed to high salinity, seed germination and seedling establishment are significantly inhibited. In particular, with the promotion of rice direct-seeding in Asia, improving rice salt tolerance during seed germination is of strong importance for rice breeding. Results In this study, we found that the indica rice landrace Wujiaozhan (WJZ) showed a high capability of seed germination under both water (H 2 O) and salt (NaCl) conditions, particularly under high salt stress. The BC 1 F 2 population produced by crossing WJZ with japonica Nipponbare (Nip) was used to evaluate the germination traits under water (H 2 O) and salt (300 mM NaCl) conditions using germination rate (GR) and germination index (GI). A total of 13 quantitative trait loci (QTLs) were identified, including eight QTLs of GR, two QTLs of GI under H 2 O conditions, six QTLs of GR, and three QTLs of GI under 300 mM NaCl conditions. Six QTLs ( qGR6.1 , qGR8.1 , qGR8.2 , qGR10.1 , qGR10.2 and qGI10.1 ) contributed to GR under both H 2 O and 300 mM NaCl conditions. Three QTLs ( qGR6.2 , qGR10.1 and qGR10.2 ) under 300 mM NaCl conditions were identified at different time points of seed germination and shared the same region with qGI6 , qGI10.1 and qGI10.2 for GI. These QTLs could be used to improve seed germination ability via marker-assisted selection (MAS). One major effective salt-tolerance-specific QTL, qGR6.2, on chromosome 6 was further confirmed via the BC 2 F 2 population, which explained more than 20% of the phenotypic variation. Fine mapping results showed that qGR6.2 was narrowed to a 65.9-kb region between the Z654 and Z619 molecular markers, with eleven candidate genes being predicted. Based on the microarray database, there were high transcript abundances of six genes ( LOC_Os06g10650 , LOC_Os06g10660 , LOC_Os06g10690 , LOC_Os06g10710 , LOC_Os06g10730 and LOC_Os06g10750 ) at all developmental stages, and only LOC_Os06g10750 was differentially expressed after salt incubation. RT-qPCR showed that two genes ( LOC_Os06g10650 and LOC_Os06g10750 ) were significantly differentially expressed at 300 mM NaCl during seed germination. This result suggested that LOC_Os06g10650 and LOC_Os06g10750 might be the causal candidate genes for the major effective salt-tolerance-specific QTL qGR6.2 identified in WJZ, which may facilitate map-based cloning and help to elucidate the molecular mechanism underlying salt tolerance during seed germination. Conclusions In our study, we identified 13 QTLs from indica landrace WJZ that confer seed germination traits under water and salt conditions. A major salt-tolerance-specific QTL qGR6.2 was confirmed and fine mapped to a 65.9-kb region flanked by the Z654 and Z619 markers. Our results provide information on the genetic basis of improving salt tolerance during seed germination by MAS.


2020 ◽  
Author(s):  
Peng Zeng ◽  
Peiwen Zhu ◽  
Luofeng Qian ◽  
Xumei Qian ◽  
Yuxin Mi ◽  
...  

Abstract Background Rice growth is frequently affected by salinity. When rice plants are exposed to high salinity, seed germination and seedling establishment are significantly inhibited. In particular, with the promotion of rice direct-seeding in Asia, improving rice salt tolerance during seed germination is of strong importance for rice breeding. Results In this study, we found that the indica rice landrace Wujiaozhan (WJZ) showed a high capability of seed germination under both water (H 2 O) and salt (NaCl) conditions, particularly under high salt stress. The BC 1 F 2 population produced by crossing WJZ with japonica Nipponbare (Nip) was used to evaluate the germination traits under water (H 2 O) and salt (300 mM NaCl) conditions using germination rate (GR) and germination index (GI). A total of 13 quantitative trait loci (QTLs) were identified, including eight QTLs of GR, two QTLs of GI under H 2 O conditions, six QTLs of GR, and three QTLs of GI under 300 mM NaCl conditions. Six QTLs ( qGR6.1 , qGR8.1 , qGR8.2 , qGR10.1 , qGR10.2 and qGI10.1 ) contributed to GR under both H 2 O and 300 mM NaCl conditions. Three QTLs ( qGR6.2 , qGR10.1 and qGR10.2 ) under 300 mM NaCl conditions were identified at different time points of seed germination and shared the same region with qGI6 , qGI10.1 and qGI10.2 for GI. These QTLs could be used to improve seed germination ability via marker-assisted selection (MAS). One major effective salt-tolerance-specific QTL, qGR6.2, on chromosome 6 was further confirmed via the BC 2 F 2 population, which explained more than 20% of the phenotypic variation. Fine mapping results showed that qGR6.2 was narrowed to a 65.9-kb region between the Z654 and Z619 molecular markers, with eleven candidate genes being predicted. Based on the microarray database, there were high transcript abundances of six genes ( LOC_Os06g10650 , LOC_Os06g10660 , LOC_Os06g10690 , LOC_Os06g10710 , LOC_Os06g10730 and LOC_Os06g10750 ) at all developmental stages, and only LOC_Os06g10750 was differentially expressed after salt incubation. RT-qPCR showed that two genes ( LOC_Os06g10650 and LOC_Os06g10750 ) were significantly differentially expressed at 300 mM NaCl during seed germination. This result suggested that LOC_Os06g10650 and LOC_Os06g10750 might be the causal candidate genes for the major effective salt-tolerance-specific QTL qGR6.2 identified in WJZ, which may facilitate map-based cloning and help to elucidate the molecular mechanism underlying salt tolerance during seed germination. Conclusions In our study, we identified 13 QTLs from indica landrace WJZ that confer seed germination traits under water and salt conditions. A major salt-tolerance-specific QTL qGR6.2 was confirmed and fine mapped to a 65.9-kb region flanked by the Z654 and Z619 markers. Our results provide information on the genetic basis of improving salt tolerance during seed germination by MAS.


PLoS ONE ◽  
2021 ◽  
Vol 16 (1) ◽  
pp. e0245505
Author(s):  
Xiaofei Chen ◽  
Ruidong Zhang ◽  
Yifan Xing ◽  
Bing Jiang ◽  
Bang Li ◽  
...  

Sorghum [Sorghum bicolor (L.) Moench] seed germination is sensitive to salinity, and seed priming is an effective method for alleviating the negative effects of salt stress on seed germination. However, few studies have compared the effects of different priming agents on sorghum germination under salt stress. In this study, we quantified the effects of priming with distilled water (HP), sodium chloride (NaCl), potassium chloride (KCl), calcium chloride (CaCl2), and polyethylene glycol (PEG) on sorghum seed germination under 150 mM NaCl stress. The germination potential, germination rate, germination index, vigor index, root length, shoot length, root fresh weight, shoot fresh weight, root dry weight, and shoot dry weight were significantly reduced by salt stress. Different priming treatments alleviated the germination inhibition caused by salt stress to varying degrees, and 50 mM CaCl2 was the most effective treatment. In addition, the mitigation effect of priming was stronger on root traits than on shoot traits. Mitigation efficacy was closely related to both the type of agent and the concentration of the solution. Principal component analysis showed that all concentrations of CaCl2 had higher scores and were clearly distinguished from other treatments based on their positive effects on all germination traits. The effects of the other agents varied with concentration. The priming treatments were divided into three categories based on their priming efficacy, and the 50, 100, and 150 mM CaCl2 treatments were placed in the first category. The 150 mM KCl, 10% PEG, HP, 150 mM NaCl, 30% PEG, and 50 mM KCl treatments were placed in the second category, and the 100 mM NaCl, 100 mM KCl, 20% PEG, and 50 mM NaCl treatments were least effective and were placed in the third category. Choosing appropriate priming agents and methods for future research and applications can ensure that crop seeds germinate healthily under saline conditions.


2017 ◽  
Vol 109 (1) ◽  
pp. 89 ◽  
Author(s):  
Soheil Karimi ◽  
Saeid ESHGHI ◽  
Saeid KARIMI ◽  
Saman HASAN-NEZHADIAN

<p>This study evaluates seed germination and growth of sweet corn under NaCl stress (0, 50, and 100 mM), after exposing the seeds to weak (15 mT) or strong (150 mT) magnetic fields (MF) for different durations (0, 6, 12, and 24 hours). Salinity reduced seed germination and plant growth. MF treatments enhanced rate and percentage of germination and improved plant growth, regardless of salinity. Higher germination rate was obtained by the stronger MF, however, the seedling were more vigorous after priming with 15 mT MF. Proline accumulation was observed in parallel with the loss of plant water content under 100 mM NaCl stress. MF prevented proline accumulation by improving water absorption. Positive correlation between H<sub>2</sub>O<sub>2</sub> accumulation and membrane thermostability (MTI) was found after MF treatments, which revealed that MF primed the plant for salinity by H<sub>2</sub>O<sub>2</sub> signaling. However, over-accumulation of H<sub>2</sub>O<sub>2</sub> after prolonged MF exposure adversely affected MTI under severe salt stress. In conclusion, magnetic priming for 6 hours was suggested for enhancing germination and growth of sweet corn under salt stress.</p>


2005 ◽  
Vol 45 (4) ◽  
pp. 391 ◽  
Author(s):  
B. Zhang ◽  
B. C. Jacobs ◽  
M. O'Donnell ◽  
J. Guo

Salt tolerances of 3 cultivars, Menemen puccinellia (Puccinellia ciliata Bor), Tyrrell and Dundas [tall wheatgrass, Thinopyrum ponticum (Podp.) Z. W. Liu and R. R. C. Wang], were compared with respect to their seed germination, adaptive responses to salt and waterlogging, seedling emergence, plant growth, shoot osmolality and mineral contents in a series of salt-stress experiments. An inverse normal distribution provided good fits for the time to seed germination. Under NaCl stress, 50% of the control (distilled water) seed germination rates of Menemen, Tyrrell and Dundas were achieved in 178.8, 300.9 and 296.8 mmol/L NaCl, respectively. Fifty percent of the control seedling emergence rates of these 3 cultivars were in 92.7, 107.2 and 113.5 mmol/L NaCl, respectively. The seed germination rates of these 3 cultivars under both salt and waterlogging stress were far lower than those germinated only under salt stress at the same salt level. Seed pretreatment by soaking seed in NaCl solutions greatly increased the seed germination rate under salt stress for Menemen and under both salt stress and waterlogging for Dundas. Tyrrell and Dundas were very similar in their tolerance to salt stress, and were significantly (P<0.05) more salt tolerant than Menemen in terms of seed germination and seedling emergence rate. Both shoot height and dry matter of these 3 cultivars were not statistically different among all salt stress levels during the seedling elongation period, indicating that the established plants of these 3 cultivars were very salt tolerant. The salt tolerance mechanisms of these 3 cultivars are possibly related to their abilities to maintain high osmolality in shoots by regulating high sodium and potassium contents, and reducing calcium deficiency under salt stress.


2009 ◽  
Vol 35 (3) ◽  
pp. 483-489 ◽  
Author(s):  
Fu-Ping WEN ◽  
Tan ZHANG ◽  
Zhao-Hui ZHANG ◽  
Ying-Hong PAN

2021 ◽  
Author(s):  
Yunyu Wu ◽  
Ning Xiao ◽  
Yuhong Li ◽  
Qiang Gao ◽  
Yuese Ning ◽  
...  

Abstract Background Rice blast is one of the most widespread and devastating diseases in rice production. Tremendous success has been achieved in identification and characterization of genes and quantitative trait loci (QTLs) conferring seedling blast resistance, however, genetic studies on panicle blast resistance have lagged far behind. Results In this study, two advanced backcross inbred sister lines (MSJ13 and MSJ18) were obtained in the process of introducing Pigm into C134S, and showed significant differences in the panicle blast resistance. One F2 population derived from the crossing MSJ13/MSJ18 was used to QTL mapping for panicle blast resistance using Genotyping by Sequencing (GBS) method. A total of 7 QTLs were identified, including a major QTL qPBR10-1 on chromosome 10 that explaining 24.21% of phenotypic variance with LOD scores of 6.62. Furthermore, qPBR10-1 was verified via the BC1F2 and BC1F3 population and narrowed to a 60.6-kb region with six candidate genes predicted, including two genes encoding exonuclease family protein, two genes encoding hypothetical protein, and two genes encoding transposon protein. The nucleotide variations and the expression patterns of the candidate genes were identified and analyzed between MSJ13 and MSJ18 through sequence comparison and RT-PCR approach, and results indicated that ORF1 and ORF2 encoding exonuclease family protein might be the causal candidate genes for panicle blast resistance in the qPBR10-1 locus. Conclusions A total of 7 QTLs conferring panicle blast resistance was identified from one F2 population derived from the crossing between two advanced backcross inbred sister lines MSJ13 and MSJ18, which harbored the broad-spectrum resistance gene Pigm. A major QTL qPBR10-1 was fine mapped in a 60.6-kb region with six candidate genes predicted, and ORF1 and ORF2 encoding exonuclease family protein might be the causal candidate genes for panicle blast resistance in the qPBR10-1 locus through sequence comparison and RT-PCR approach.


Euphytica ◽  
2010 ◽  
Vol 178 (3) ◽  
pp. 297-307 ◽  
Author(s):  
Zhoufei Wang ◽  
Jianfei Wang ◽  
Yongmei Bao ◽  
Yunyu Wu ◽  
Hongsheng Zhang

Rice Science ◽  
2010 ◽  
Vol 17 (2) ◽  
pp. 105-110 ◽  
Author(s):  
Zhou-fei WANG ◽  
Jian-fei WANG ◽  
Yong-mei BAO ◽  
Yun-yu WU ◽  
Xuan SU ◽  
...  

Sign in / Sign up

Export Citation Format

Share Document