Differential responses of sorghum genotypes to drought stress revealed by physio-chemical and transcriptional analysis.

Sorghum is an essential food crop for millions of people in the semi-arid regions of the world, where its production is severely limited by drought stress. Drought in the early stages of crop growth and development irreversibly interferes, which leads to poor yield. The effect of drought stress in sorghum was studied at physiological, biochemical, and molecular levels in a set of two genotypes differing in their tolerance to drought. Drought stress was imposed by restraining water for 10 days on 25 days old seedlings. A significant influence of water stress was observed on the considered morpho-physiological and biochemical traits. The genotype DRT1019 exhibited physiological and biochemical indicators of drought avoidance through delayed leaf rolling, osmotic adjustment, ideal gas-exchange system, solute accumulation, an increased level of enzyme synthesis and root trait expression as compared to the ICSV95022 genotype. Furthermore, differences in the metabolite changes viz. total carbohydrate, total amides, and lipids were found between the two genotypes under drought stress. In addition, transcript profiling of potential candidate drought genes such as SbTIP3-1, SbDHN1, SbTPS, and SbDREB1A revealed up-regulation in DRT1019, which corresponded with other important physiological and biochemical parameters exhibited in the genotype. In conclusion, this study provides an improved understanding of whole plant response to drought stress in sorghum. Additionally, our results provide promising candidate genes for drought tolerance in sorghum that can be used as potential markers for drought tolerance breeding programs.

Heparin vs Saline Infusion to Maintain Patency of Arterial Catheters in Children: A Randomized, Double-Blind, Noninferiority Trial.

OBJECTIVE: To determine whether normal saline flush solution is noninferior to heparinised saline for maintaining the patency of arterial intravascular catheters in children. METHODS: A single centre, double blind, parallel group, noninferiority, randomized control study was conducted in the Pediatric Intensive Care Unit of Kanchi Kamakoti CHILDS Trust hospital, a tertiary children's hospital, Chennai, India. 92 children requiring arterial catheters for more than 12 hours were randomized to receive either normal saline or heparinized saline (1 U/ml) flush solution. Primary outcome was a noninferiority comparison between normal saline and heparinised saline in maintaining the patency of arterial catheters using the proportion of occlusion of arterial catheters as primary endpoint. Secondary outcome was mean duration of patency of arterial catheters in each treatment group. RESULTS: Ninety-two children with a median (interquartile range, age of 84 (33.5-132) months and 52% males were enrolled. 15.2% of catheters in the heparin group and 17.4% of catheters in the normal saline group were occluded (P = 0.77). The 95% upper confidence interval for the difference in proportion was 0.148 (+14.8%), establishing noninferiority (< 15%). The median (IQR) duration of a patent arterial catheter was 47 (27.75 - 94.5) hours in the heparin group and 35.50 (24.50 - 62) hours in the normal saline group (P = 0.10). Comparison of duration of patency using Kaplan Meier survival analysis and log rank test showed no statistically significant difference. There were no serious adverse events noted in either group. CONCLUSIONS: Our data suggests that normal saline is noninferior to heparinized saline infusion in maintaining the patency of arterial lines in children. This may benefit clinicians worldwide as normal saline would be a safer and cost-effective option.