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The Khangchendzonga Landscape (KL), a part of 'Himalayan Biodiversity Hotspot', is known for its unique biodiversity assemblage. In recent years, the KL is experiencing threats to biodiversity due to the biological overdominance of native Maling bamboo (Yushania maling). In the present study, we investigated the impacts of the overdominance of Y. maling on the forest composition of Singalila National Park (SNP), Eastern Himalaya, India. Elevational habitats 2400 to 3400 m asl were sampled by laying 69 (10 m × 10 m) forest plots including 51 bamboo plots and 18 non-bamboo plots. Bamboo plots showed significantly (p < 0.05) low species richness and density in both shrub and herb layers which further manifested the low seedling density. Generalized Additive Model (GAM) estimated a significant (p < 0.0001) decline in species richness and density with increasing bamboo density in SNP. Our study projects the overdominance of Y. maling has a significant negative impact on forest structure and composition. Therefore, management of invasiveness of Y. maling is essential through its optimized removal from the protected areas and utilization in making handicrafts, paper industries etc. to create ecological and economic benefits. Further long-term studies assessing the impacts of Y. maling overdominance on forest ecosystems and soil dynamics are recommended. [ABSTRACT FROM AUTHOR]

Shoot fly (Atherigona naqvii) is one of the major insects affecting spring maize in North India and can cause yield loss up to 60 per cent. The genetics of insect resistance is complex as influenced by genotypic background, insect population and climatic conditions. Therefore, quantitative trait loci (QTL) mapping is a highly effective approach for studying genetically complex forms of insect resistance. The objective of the present study was to dissect the genetic basis of resistance and identification of genomic regions associated with shoot fly resistance. A total of 107 F2 population derived from the cross CM143 (resistant) x CM144 (susceptible) was genotyped with 120 SSR markers. Phenotypic data were recorded on replicated F2:3 progenies for various component traits imparting resistance to shoot fly at different time intervals. Resistance to shoot fly was observed to be under polygenic control as evidenced by the identification of 19 putative QTLs governed by overdominance to partial dominance and additive gene actions. The major QTLs conditioning shoot fly resistance viz., qDH9.1 (deadheart) and qEC9.1 (oviposition) explaining 15.03 and 18.89 per cent phenotypic variance, respectively were colocalized on chromosome 9. These QTLs are syntenic to regions of chromosome 10 of sorghum which were also accounted for deadheart and oviposition suggesting that the same gene block may be responsible for shoot fly resistance. The candidate genes such as cysteine protease, subtilisin-chymotrypsin inhibitor, cytochrome P450 involved in synthesis of alleochemicals, receptor kinases, glossy15 and ubiquitin-proteasome degradation pathway were identified within the predicted QTL regions. This is the first reported mapping of QTLs conferring resistance to shoot fly in maize, and the markers identified here will be a valuable resource for developing elite maize cultivars with resistance to shoot fly. [ABSTRACT FROM AUTHOR]

The present study involved assessment of 70 three-line hybrids obtained by crossing five CMS lines and 14 testers using line x tester mating design for combining ability and heterosis for 13 yield and grain quality traits. The Analysis of Variance identified significant difference among crosses and the ratio of GCA and SCA variances were less than unity indicating non-additive gene action for all the traits. The line COMS 24A and testers RNR 15048, WGL 32100, CBSN 504, CBSN 509, CBSN 511 and IR64 DRT were identified as best general combiners through gca effects. Among the hybrids, COMS 24A X WGL 32100, COMS 24A X CBSN 504, COMS 25A X CBSN 511, COMS 25A X CBSN 517, COMS 23A X IR64 DRT and COMS 23A X CBSN 509 demonstrated outstanding sca effects, mean and standard heterosis over CORH 3 and CORH 4. Two hybrids viz., COMS 25A X CBSN 511 and COMS 25A X RNR 15048 had medium slender grain type and hold promise for commercial exploitation in south India especially Tamil Nadu. [ABSTRACT FROM AUTHOR]

The C-C motif chemokine ligand-2 (CCL2) was evidenced to be associated with tuberculosis susceptibility in some ethnic groups. In the present study, effort was made to find out the association of CCL2-2518 A>G and -362 G>C variants with susceptibility to TB in a population from North India. The genotyping was carried out in 373 participants with pulmonary TB (PTB) and 248 healthy controls (HCs) for CCL2-2518 A>G and -362 G>C polymorphisms by PCR-RFLP and by melting curve analysis using fluorescence-labeled hybridization fluorescent resonance energy transfer (FRET) probes, respectively, followed by DNA sequencing in a few representative samples. Genotype and allele frequencies were compared by the chi-squared test and crude and Mantel-Haenszel (M-H) odds ratio (OR). OR was calculated using STATA/MP16.1 software. Further, CCL2, IL-12p70, IFN-γ, TNF-α, and TGF-β levels were measured in serum samples of these participants using commercially available kits. Our analysis indicated that the homozygous mutant in both -2518 GG (OR = 2.07, p = 0.02) and -362 CC (OR = 1.92, p = 0.03) genotypes was associated with susceptibility to pulmonary TB. Further, heterozygous genotypes -2518AG (OR = 0.60, p = 0.003) and -362GC (OR = 0.64, p = 0.013) provide resistance from PTB disease. Haplotype analysis revealed AC haplotype (p = 0.006) to be a risk factor associated with PTB susceptibility. The serum CCL2 level was significantly elevated among participants with -2518 AA genotype compared to -2518 GG genotype. CCL2 level was observed to be positively correlated with IL12p70, IFN-γ and TNF-α, thus suggesting the immunological regulatory role of CCL2 against pulmonary tuberculosis. CCL2-2518 GG and -362 CC genotypes were found to be associated with susceptibility to pulmonary tuberculosis and CCL2-2518AG and CCL2-362GC with resistance from PTB. AC haplotype was found to be a risk factor for PTB in the present study. It may be hypothesized from the findings that -2518G allele could be responsible for lower production of CCL2 which leads to defective Th1 response and makes a host susceptible for pulmonary tuberculosis. [ABSTRACT FROM AUTHOR]

Indian population is an amalgamation of various ethnicities, cultural and linguistic diversities, primarily due to marriages within a community. HLA-A, B and DRB1 alleles and haplotype frequencies were investigated in the Sindhi and compared with Marathi, Gujarati and North Indian population from Mumbai. This work is a part of a larger effort aimed at analysis of the HLA profile of diverse Indian ethnics to establish an umbilical cord stem cell panel in India. HLA polymorphisms at the HLA-A, B and DRB1 loci were determined in 413 cord blood samples by the molecular method of polymerase chain reaction using sequence-specific primer amplification. The most frequent alleles included A*01, A*02, A*11 and A*24 at A locus, B*35 and B*40 at B locus and DRB1*07 and DRB1*15 in all the four groups, although the frequency fluctuated in individual communities. HLA-DRB1*03 was significantly high ( P < 0.05) in the Sindhi. Phylogenetic association using neighbour-joining tree, based on DA genetic distances for HLA-A and HLA-B alleles, indicated that the Sindhis cluster with North Indian and Pakistan Sindhi. The three locus haplotype analysis revealed that A*02-B*40-DRB1*15 and A*33-B*44-DRB1*07 were common haplotypes in all the groups. The three locus haplotypes found suggest an influence from Caucasian and Oriental populations. The data will be useful in developing an umbilical cord stem cell panel in India. The results will have clinical implications in unrelated umbilical cord stem cell for transplantation in India. [ABSTRACT FROM AUTHOR]