Drought stress is the major constraint to rice (Oryza sativa L.) production and yield stability in rainfed ecosystems. Identifying genomic regions contributing to drought resistance will help develop rice cultivars suitable for rainfed regions through molecular marker assisted breeding. Quantitative trait loci (QTLs) linked to plant water stress indicators, phenology and production traits under irrigated and drought stress conditions were mapped by means of a doubled‐haploid (DH) population of 154 rice lines from the cross CT9993‐5‐10‐1‐M/IR62266‐42‐6‐2. The DH lines were subjected to water stress before anthesis in three field experiments at two locations. The DH lines showed significant variation for plant water stress indicators, phenology, plant biomass, yield and yield components under irrigated control and water stress. A total of 47 QTLs were identified for various plant water stress indicators, phenology, and production traits under control and water stress conditions in the field, which individually explained 5 to 59% of the phenotype variation. A region was identified on chromosome 4 that harbored major QTLs for plant height, grain yield, and number of grains per panicle under drought stress. By comparing the coincidence of QTLs with specific traits, we also genetically dissected the nature of association of root traits and capacity for osmotic adjustment with rice production under drought. Root traits had positive correlations with yield and yield components under drought stress. This study demonstrated that the region RG939‐RG476‐RG214 on chromosome 4 identified for root‐related drought resistance component QTLs also had pleiotropic effects on yield traits under stress. Consistent QTLs for drought resistance traits and yield under stress were detected and might be useful for marker‐assisted selection for rainfed rice improvement.

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A field survey was conducted for chronic obstructive pulmonary disease (COPD) epidemiology in the rural field practice area of Kempegowda Institute of Medical Sciences, Bangalore, India, which covers a population of 44,387 to find out the prevalence of COPD in adult subjects of 35 years and above using cluster sampling technique and to determine the association of tobacco smoking, environmental tobacco smoking (ETS) exposure and type of cooking fuel used with COPD. The overall prevalence of COPD was 4.36%. The prevalence among males and females were 5.32% and 3.41% respectively. The prevalence was found to be increasing with an increase in age. The tobacco smoke and exposure to ETS was significantly associated with higher odds of COPD with adjusted odds ratio 2.97 and 2.67 respectively. Thus, there was a significant association between tobacco smoking and ETS exposure with COPD.

Finger millet [Eleusine coracana (L.) Gaertn.] is an important climate-resilient nutrient-dense crop grown as a staple food grain in Asia and Africa. Utilizing the full potential of the crop mainly depends on an in-depth exploration of the vast diversity in its germplasm. In this study, the global finger millet germplasm diversity panel of 314 accessions was genotyped, using the DArTseq approach to assess genetic diversity and population structure. We obtained 33,884 high-quality single nucleotide polymorphism (SNP) markers on 306 accessions after filtering. Finger millet germplasm showed considerable genetic diversity, and the mean polymorphic information content, gene diversity, and Shannon Index were 0.110, 0.114, and 0.194, respectively. The average genetic distance of the entire set was 0.301 (range 0.040 – 0.450). The accessions of the race elongata (0.326) showed the highest average genetic distance, and the least was in the race plana (0.275); and higher genetic divergence was observed between elongata and vulgaris (0.320), while the least was between compacta and plana (0.281). An average, landrace accessions had higher gene diversity (0.144) and genetic distance (0.299) than the breeding lines (0.117 and 0.267, respectively). A similar average gene diversity was observed in the accessions of Asia (0.132) and Africa (0.129), but Asia had slightly higher genetic distance (0.286) than African accessions (0.276), and the distance between these two regions was 0.327. This was also confirmed by a model-based STRUCTURE analysis, genetic distance-based clustering, and principal coordinate analysis, which revealed two major populations representing Asia and Africa. Analysis of molecular variance suggests that the significant population differentiation was mainly due to within individuals between regions or between populations while races had a negligible impact on population structure. Finger millet diversity is structured based on a geographical region of origin, while the racial structure made negligible contribution to population structure. The information generated from this study can provide greater insights into the population structure and genetic diversity within and among regions and races, and an understanding of genomic-assisted finger millet improvement.

The present experiment was conducted at Sugarcane Breeding Institute (ICAR), Coimbatore to generate diverse genetic stocks for resistance to red rot disease caused by Colletotrichum falcatum Went. and other important economic traits. This study was carried out with progenies obtained from 39 crosses involving 45 parental clones of interspecific and intervarietal origin. The interspecific origin involves diverse forms of Saccharum officinarum and S. spontaneum that are hitherto unutilized in the breeding programme. The progenies were evaluated for resistance to red rot disease and economic traits such as cane yield and quality. Out of 39 crosses investigated for race specific resistance as a qualitative trait, 18 crosses showed a simple Mendelian segregation of monogenic nature. Parent progeny regression analysis suggested that about 50% of the variation in the population could be attributed to additive genetic variance (horizontal resistance). Two crosses involving susceptible parents viz., 971235 (S) x Co 1148 (S) and Co 88028 (S) x Co 775 (S) contributed 28-30% resistant progenies. These transgressive segregants are likely to be stable in their resistance due to additive genetic action and could be used as donor parents in red rot resistance breeding programmes for imparting race non-specific resistance. The present investigation has also identified some specific cross combinations for yield, quality in addition to red rot resistance for further exploitation in breeding programme.