Drought-tolerance QTLs commonly detected in two sets of reciprocal introgression lines in rice

2014 ◽  
Vol 65 (2) ◽  
pp. 171 ◽  
Author(s):  
Yun Wang ◽  
Qiang Zhang ◽  
Tianqing Zheng ◽  
Yanru Cui ◽  
Wenzhong Zhang ◽  
...  

Drought is one of the major abiotic stresses limiting rice (Oryza sativa L.) production. Quantitative trait loci (QTLs) for drought tolerance (DT) at the reproductive stage were identified with two sets of reciprocal introgression lines derived from Lemont × Teqing. In total, 29 and 23 QTLs were identified in the Teqing and Lemont backgrounds, respectively, during the reproductive stage under drought and irrigated conditions for spikelet number per panicle, seed fertility, filled grain weight per panicle, plant height, and grain yield per plant. Most of these QTLs showed obvious differential expressions in response to drought stress. Another 21 QTLs were detected by the ratio of trait values under drought stress relative to the normal irrigation conditions in the two backgrounds. For 28 DT QTLs, the Teqing alleles at 23 loci had increased trait values and could improve DT under drought stress. Only five (17.9%) DT QTLs (QSnp1b, QSnp3a, QSnp11, QSf8, and QGyp2a) were consistently detected in the two backgrounds, clearly suggesting overwhelming genetic background effects on QTL detection for DT. Seven of the DT QTL regions identified were found to share the same genomic regions with previously reported DT-related genes. Introgressing or pyramiding of favourable alleles from Teqing at the validated QTLs (QSnp3a, QSnp11 and QGyp2a) into Lemont background may improve DT level of Lemont.

Agriculture ◽  
2021 ◽  
Vol 11 (1) ◽  
pp. 64
Author(s):  
Priyanka Dwivedi ◽  
Naleeni Ramawat ◽  
Gaurav Dhawan ◽  
Subbaiyan Gopala Krishnan ◽  
Kunnummal Kurungara Vinod ◽  
...  

Reproductive stage drought stress (RSDS) is detrimental for rice, which affects its productivity as well as grain quality. In the present study, we introgressed two major quantitative trait loci (QTLs), namely, qDTY2.1 and qDTY3.1, governing RSDS tolerance in a popular high yielding non-aromatic rice cultivar, Pusa 44, through marker-assisted backcross breeding (MABB). Pusa 44 is highly sensitive to RSDS, which restricts its cultivation across drought-prone environments. Foreground selection was carried out using markers, RM520 for qDTY3.1 and RM 521 for qDTY2.1. Background selection was achieved with 97 polymorphic SSR markers in tandem with phenotypic selection to achieve faster recurrent parent genome (RPG) recovery. Three successive backcrosses followed by three selfings aided RPG recoveries of 98.6% to 99.4% among 31 near isogenic lines (NILs). Fourteen NILs were found to be significantly superior in yield and grain quality under RSDS with higher drought tolerance efficiency (DTE) than Pusa 44. Among these, the evaluation of two promising NILs in the multilocational trial during Kharif 2019 showed that they were significantly superior to Pusa 44 under reproductive stage drought stress, while performing on par with Pusa 44 under normal irrigated conditions. These di-QTL pyramided drought-tolerant NILs are in the final stages of testing the All India Coordinated Rice Improvement Project varietal trials for cultivar release. Alternately, the elite drought-tolerant Pusa 44 NILs will serve as an invaluable source of drought tolerance in rice improvement.


2020 ◽  
Vol 10 (13) ◽  
pp. 4471
Author(s):  
Didar Rahim ◽  
Petr Kalousek ◽  
Nawroz Tahir ◽  
Tomáš Vyhnánek ◽  
Petr Tarkowski ◽  
...  

Rice (Oryza sativa L.) is productively affected by different environmental factors, including biotic and abiotic stress. The objectives of this research were to evaluate the genetic distinction among Kurdish rice genotypes using the simple sequence repeats (SSRs) molecular markers and to perform in vitro tests to characterize the drought tolerance of six local rice genotypes. The polymorphic information content (PIC) varied from 0.38 to 0.84 with an average of 0.56. The genetic distance ranged from 0.33 to 0.88. Drought stress had a significant impact (p ≤ 0.05) on callus growth parameters. Enzymatic antioxidant systems were predicted and exhibited a significant variation. The findings revealed that proline levels increase in proportion to polyethylene glycol (PEG) concentrations. Kalar and Gwll Swr genotypes showed the worst performances in phenotypic and biochemical traits, while Choman and Shawre exhibited the best phenotypic and biochemical performances. A positive and substantial relationship between callus fresh weight (CFW) and callus dry weight (CDW) was found under stressful and optimized conditions. Callus induction (CI) was positively and significantly associated with the catalase activity (CAT) in all stressed treatments. Based on the results for callus growth and the biochemical parameters under stress conditions, a remarkable genotype distinction, based on the tolerance reaction, was noted as follows: PEG resistant > susceptible, Choman > Shawre > White Bazyan > Red Bazyan > Gwll Swr > Kalar. The CI and CAT characteristics were considered as reliable predictors of drought tolerance in rice genotypes.


2018 ◽  
Vol 16 (1) ◽  
pp. 44-54 ◽  
Author(s):  
M M Islam ◽  
E Kayesh ◽  
E Zaman ◽  
T A Urmi ◽  
M M Haque

Drought stress is a major constraint to the production and yield stability of crops. Rice (Oryza sativa L.) is considered as a drought-sensitive crop species. Within this species, there are considerable varietal differences in sensitivity to this environmental stress. An experiment was conducted at the laboratory of the Department of Agronomy, Bangabandhu Sheikh Mujibur Rahman Agricultural University (BSMRAU), Bangladesh during April to September 2016 to evaluate 100 rice genotypes for drought tolerance during germination and early seedling growth stage. The genotypes were tested against five levels of drought stress imposed by Polyethylene glycol 6000 (PEG-6000) @ 0, 5, 10, 15 and 20%. The experiment was laid out in a complete randomized design with four replications. The results showed that with increasing water stress, germination in all the genotypes decreased from 95.8% in control to 6.6 % in highest stress (20% PEG) level. Seedling height and dry weight also decreased in all rice genotypes with the increase in water stress level. Based on Standard Evaluation System (SES),18 genotypes were selected primarily. Among the 18 genotypes, Ratoil and Chinisakkar showed higher germination index, relative seedling height and relative seedling dry weight than the check drought tolerant BRRI dhan43 at 20% PEG. Beside these, performance of Kumridhan, Pusur and Somondori was also well at this level compared to BRRI dhan43. The genotypes Ratoil, Chinisakkar, Kumridhan, Pusur and Somondori showed the best performance under drought condition. The Agriculturists 2018; 16(1) 44-54


2020 ◽  
Vol 8 (9) ◽  
pp. 1329
Author(s):  
Zhiqiang Pang ◽  
Ying Zhao ◽  
Peng Xu ◽  
Diqiu Yu

Among abiotic stresses, drought is one of the most important factors limiting plant growth. To increase their drought tolerance and survival, most plants interact directly with a variety of microbes. Upland rice (Oryza sativa L.) is a rice ecotype that differs from irrigated ecotype rice; it is adapted to both drought-stress and aerobic conditions. However, its root microbial resources have not been explored. We isolated bacteria and fungi from roots of upland rice in Xishuangbanna, China. Four hundred sixty-two endophytic and rhizospheric isolates (337 bacteria and 125 fungi) were distributed. They were distributed among 43 genera on the basis of 16S rRNA and internal transcribed spacer (ITS) gene sequence analysis. Notably, these root microbes differed from irrigated rice root microbes in irrigated environments; for example, members of the Firmicutes phylum were enriched (by 28.54%) in the roots of the upland plants. The plant growth-promoting (PGP) potential of 217 isolates was investigated in vitro. The PGP ability of 17 endophytic and 10 rhizospheric isolates from upland rice roots was evaluated under well-irrigated and drought-stress conditions, and 9 fungal strains increased rice seedling shoot length, shoot and root fresh weight (FW), antioxidant capability, and proline (Pro) and soluble sugar contents. Our work suggests that fungi from upland rice roots can increase plant growth under irrigated and drought-stress conditions and can serve as effective microbial resources for sustainable agricultural production in arid regions.


Rice ◽  
2017 ◽  
Vol 10 (1) ◽  
Author(s):  
B. P. Mallikarjuna Swamy ◽  
Noraziyah Abd Aziz Shamsudin ◽  
Site Noorzuraini Abd Rahman ◽  
Ramil Mauleon ◽  
Wickneswari Ratnam ◽  
...  

Author(s):  
Lourine Chebet Bii ◽  
Kahiu Ngugi ◽  
John M. Kimani ◽  
George N. Chemining’ wa

In Kenya, the key abiotic stress affecting rice production is drought stress which is experienced mainly during reproductive phase of the crop. This study evaluated the performance of Kenyan rice populations including 19 generation of crosses, 6 parental and 5 checks under well-watered and drought stressed environment with the aim of identifying the phenotypic traits that confer drought tolerance in rice. The 19 generation of crosses were in F3 when they were evaluated in the short rains season and later advanced to F4 in the long rains season. Nineteen generation of crosses rice (Oryza sativa L.) lines, six parental and five check lines were evaluated for response to drought under drought stressed and well-watered environment. The study was conducted over two seasons in the year 2016/2017 at Kenya Agricultural Livestock Research Organization (KALRO) -Mwea Centre. The experiment was set up in an alpha lattice design with three replications. Drought stress was imposed at panicle initiation by withholding irrigation till physiological maturity meanwhile the well-watered environment continued to enjoy the recommended irrigation regime from planting to physiological maturity. Yield data were scored for drought tolerance. AMMI analysis of variance for grain yield showed that genotypes from crosses of crosses of SARO5XNERICA11, NERICA2XSARO5 and NERICA15XSARO5 expressed high grain yield. AMMI stability Variance (ASV) showed genotypes NERICA15, Duorado Precoce and progenies from crosses of NERICA11XNERICA2, SARO5XKomboka and NERICA2XNERICA11 expressed high stability in both well-watered and drought-stressed environment. GGE analysis showed that Principal Components (PC1) and PC2 accounted for 96.46% and 3.54%, respectively. GGE biplots showed that genotypes from crosses SARO5XNERICA11 and NERICA15XSARO5 were the most stable and high yielding. GGE biplots ranked the rice lines as follows: those above average in performance, the stable ones, unstable and those below average in performance. SARO5XNERICA11 is worth of selection due to its high mean yield value and is stable across the mega-environments.


Plant Science ◽  
2008 ◽  
Vol 174 (6) ◽  
pp. 618-625 ◽  
Author(s):  
Xiu-Qin Zhao ◽  
Jian-Long Xu ◽  
Ming Zhao ◽  
Renee Lafitte ◽  
Ling-Hua Zhu ◽  
...  

Sign in / Sign up

Export Citation Format

Share Document