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Drought and submergence are the two major limiting factors that reduce rice production. In this study, the relevance of yield traits through path analysis under drought and submergence conditions to improve grain yield of rice, from dry season 2014-2015 and genotypic analysis using SSR markers was evaluated, during 2015-2016. Path analysis indicated that the number of panicles/clusters had the highest and a direct positive effect on the grain yield, followed by the number of filled-grain/panicle, and the harvest index compared to other component traits. These traits could be used as selection criteria for high yield and drought tolerance in populations of rice. There were two markers including RM201 (210-225 bp) and RM219 (210-215 bp) chosen to select parents in backcrossing because production of polymorphic bands relevant to submergence and drought tolerance genes. By the BC 1 F 1 and BC 2 F 1 generations of the cross OM6162/Swarnasub1//OM6162, primers RM201 and RM219 were identified drought and submergence tolerant individuals. These lines will be used in breeding programme for release of both drought and submergence tolerant with considerable yield in next step. Findings of this study are promising to develop rice cultivars tolerant to both drought and submergence, and may therefore help to reduce detrimental impacts from climate changes to rice production.

Tuberculosis (TB) has been a threat to world health for decades. Multidrug-resistant TB (MDR-TB) is adding to the burden of disease and hindering the development of countries. This study aimed to identify the drug-resistant rate in patients with recurrent pulmonary TB and detect rifampicin resistance mutations in the rpoB gene in Can Tho, Vietnam. In this descriptive cross-sectional study, clinicians diagnosed the patients with recurrent pulmonary TB and were hospitalized. Smear-positive sputum specimens (n=246) were collected to determine the rate of drug resistance. To identify mutations in the rpoB gene which are likely to be associated with rifampicin resistance in MDR-TB, we sequenced 40 isolates of Mycobacterium tuberculosis collected between 2012 and 2014; mainly MDR-TB (n=40; 95.2%) and rifampicin-sensitive TB (n=2; 4.8%). The rate of drug-resistant pulmonary tuberculosis was 63.8%, and the rate of MDR-TB accounted for 23.2%. The mutations in rpoB were predominantly in codons 531 (27.5%) and 523 (17.5%), with rare occurrences of S522A (2.5%) and A532P (2.5%). Noticeably, there was a substitution mutation in codon 532, and a mutant strain of tuberculosis at seven codons in the rpoB gene had been detected. In conclusion, this study provided drug-resistant characteristics in patients with recurrent pulmonary TB and mutations of MDR-TB in Can Tho, Vietnam. The results show a mutation in codon 532 of the rpoB gene and a mutant strain of tuberculosis at all seven codons. These are remarkable and promising results for further studies and clinical applications.