The present study aims to identify QTL influencing agronomic traits and yield components under well-watered and pre-flowering drought stress conditions. One hundred F5 recombinant inbred lines (RIL) and the parental l...The present study aims to identify QTL influencing agronomic traits and yield components under well-watered and pre-flowering drought stress conditions. One hundred F5 recombinant inbred lines (RIL) and the parental lines of a cross between a drought-tolerant and a susceptible line in a field experiment were carried out at Nong Lam University of Ho Chi Minh City, Vietnam. Drought stress was induced by withholding irrigation water from the plants at four weeks after sowing to flowering. Leaf area of the third leaf, stem diameter, plant height, days to heading, anthesis and maturity, panicle length, number of seeds per plant, hundred kernel weight and grain yield were measured. Plants were genotyped with 117 Diversity Arrays Technology (DArT) and eight expressed sequence tag (EST)-derived simple sequence repeat (SSR) markers. Composite interval mapping was carried out on the traits and significant QTL were claimed at a logarithm of the odds (LOD) score >2.5. A total of 50 QTL were detected on nine chromosomes or 13 linkage groups, respectively. Six promising QTL regions with seven QTL for yield and agronomic traits especially related to pre-flowering drought tolerance were identified on chromosomes SBI-01, SBI-03, SBI-04, SBI-05 and SBI-07.展开更多
The regulatory mechanisms of drought and salt-associated miRNAs have not been fully understood in Sorghum bicolor. In this study, we investigated the effect of salinity stress (200 and 300 mM NaCl) and drought stress ...The regulatory mechanisms of drought and salt-associated miRNAs have not been fully understood in Sorghum bicolor. In this study, we investigated the effect of salinity stress (200 and 300 mM NaCl) and drought stress at pre- and post-flowering stages on the expression pattern of small regulatory RNAs in six Sorghum genotypes using semi-quantitative reverse transcriptase PCR (RT-qPCR). The results indicated that both drought and salt stresses altered the expression pattern of miRNAs in a dose-dependent manner. However, each miRNA responded to drought and salt stress in a different pattern among the six sorghum genotypes. miR156, miR167, miR168 and miR399 give different expressions levels compared to other studied miRNAs which may attribute to the adaption of sorghum to drought and salt stress and are good candidates for improving sorghum by transgenic technology.展开更多
基金The authors would like to thank SiekeSchaepe for DNA extractionWe gratefully acknowledge the Ministry for Education and Training,Vietnam,for financial support.
文摘The present study aims to identify QTL influencing agronomic traits and yield components under well-watered and pre-flowering drought stress conditions. One hundred F5 recombinant inbred lines (RIL) and the parental lines of a cross between a drought-tolerant and a susceptible line in a field experiment were carried out at Nong Lam University of Ho Chi Minh City, Vietnam. Drought stress was induced by withholding irrigation water from the plants at four weeks after sowing to flowering. Leaf area of the third leaf, stem diameter, plant height, days to heading, anthesis and maturity, panicle length, number of seeds per plant, hundred kernel weight and grain yield were measured. Plants were genotyped with 117 Diversity Arrays Technology (DArT) and eight expressed sequence tag (EST)-derived simple sequence repeat (SSR) markers. Composite interval mapping was carried out on the traits and significant QTL were claimed at a logarithm of the odds (LOD) score >2.5. A total of 50 QTL were detected on nine chromosomes or 13 linkage groups, respectively. Six promising QTL regions with seven QTL for yield and agronomic traits especially related to pre-flowering drought tolerance were identified on chromosomes SBI-01, SBI-03, SBI-04, SBI-05 and SBI-07.
文摘The regulatory mechanisms of drought and salt-associated miRNAs have not been fully understood in Sorghum bicolor. In this study, we investigated the effect of salinity stress (200 and 300 mM NaCl) and drought stress at pre- and post-flowering stages on the expression pattern of small regulatory RNAs in six Sorghum genotypes using semi-quantitative reverse transcriptase PCR (RT-qPCR). The results indicated that both drought and salt stresses altered the expression pattern of miRNAs in a dose-dependent manner. However, each miRNA responded to drought and salt stress in a different pattern among the six sorghum genotypes. miR156, miR167, miR168 and miR399 give different expressions levels compared to other studied miRNAs which may attribute to the adaption of sorghum to drought and salt stress and are good candidates for improving sorghum by transgenic technology.
