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The invasive South American Leaf miner, Phthorimaea (=Tuta) absoluta Meyrick (Lepidoptera: Gelechiidae) is now getting a status of key pest in India. Biology studies carried out on tomato revealed that the P. absoluta had four larval instars. The total life cycle of P. absoluta lasted for 20.62 ± 0.66 days with an egg, larval and pupal periods of 2.54 ± 0.15, 9.54 ± 0.31 days and 8.54 ± 0.20 days, respectively. The longevity of female (40.00 ± 0.49 days) was found longer than the males which lasted for 36.45 ± 0.21 days. The biology studies carried out at different temperature conditions revealed the lowest egg (3.00 ± 0.24), larval (10.00 ± 0.27), pupal (9.00 ± 0.27) period, high fecundity (211.00 ± 2.54/female), highest female (40.00 ± 0.49) and male (36.45 ± 0.21) longevity at 30oC. Studies on the spatial distribution of eggs by P. absoluta revealed that the P. absoluta adults mostly preferred to lay the eggs on upper leaf surface (6.07 eggs) followed by lower surface of leaves (5.79 eggs). Ovipositional preference studies on different solanaceous crops viz., tomato, brinjal, potato, chilli and European black nightshade revealed that the adults of P. absoluta highly preferred tomato (233.70 and 326.00 eggs plant-1) followed by potato (95.90 and 143.20 eggs plant-1) both under free and no choice conditions, respectively. Biology of P. absoluta on other solanaceous crops revealed that the total life cycle was the shortest on tomato (22.00 ± 0.61) followed by European black nightshade (27.75 ± 0.84 days). However, no eggs hatched on chilli. [ABSTRACT FROM AUTHOR]

Immune heterogeneity in wild host populations indicates that disease-mediated selection is common in nature. However, the underlying dynamic feedbacks involving the ecology of disease transmission, evolutionary processes, and their interaction with environmental drivers have proven challenging to characterize. Plague presents an optimal system for interrogating such couplings: Yersinia pestis transmission exerts intense selective pressure driving the local persistence of disease resistance among its wildlife hosts in endemic areas. Investigations undertaken in colonial India after the introduction of plague in 1896 suggest that, only a decade after plague arrived, a heritable, plague-resistant phenotype had become prevalent among commensal rats of cities undergoing severe plague epidemics. To understand the possible evolutionary basis of these observations, we developed a mathematical model coupling environmentally forced plague dynamics with evolutionary selection of rats, capitalizing on extensive archival data from Indian Plague Commission investigations. Incorporating increased plague resistance among rats as a consequence of intense natural selection permits the model to reproduce observed changes in seasonal epidemic patterns in several cities and capture experimentally observed associations between climate and flea population dynamics in India. Our model results substantiate Victorian era claims of host evolution based on experimental observations of plague resistance and reveal the buffering effect of such evolution against environmental drivers of transmission. Our analysis shows that historical datasets can yield powerful insights into the transmission dynamics of reemerging disease agents with which we have limited contemporary experience to guide quantitative modeling and inference. [ABSTRACT FROM AUTHOR]

Foot-and-mouth disease (FMD) virus serotype O Ind2001 lineage within the Middle East–South Asia topotype is the major cause of recent FMD incidences in India. A sub-lineage of Ind2001 caused severe outbreaks in the southern region of the country during 2013 and also reported for the first time from Libya. In this study, we conducted a detailed evolutionary analysis of Ind2001 lineage. Phylogenetic analysis of Ind2001 lineage based on maximum likelihood method revealed two major splits and three sub-lineages. The mean nucleotide substitution rate for this lineage was calculated to be 6.338 × 10 −3 substitutions/site/year (s/s/y), which is similar to those of PanAsian sub-lineages. Evolutionary time scale analysis indicated that the Ind2001 lineage might have originated in 1989. The sub-lineage Ind2001d that caused 2013 outbreaks seems to be relatively more divergent genetically from other Ind2001 sub-lineages. Seven codons in the VP1 region of Ind2001 were found to be under positive selection. Four out of 24 recent Ind2001 strains tested in 2D-MNT had antigenic relationship value of <0.3 with the serotype O vaccine strain indicating intra-epidemic antigenic diversity. Amino acid substitutions found in these minor variants with reference to antigenic diversity have been discussed. The dominance of antigenically homologous strains indicates absence of vaccine immunity in the majority of the affected hosts. Taken together, the evolution of Ind2001 lineage deviates from the strict molecular clock and a typical lineage evolutionary dynamics characterized by periodic emergence and re-emergence of Ind2001 and PanAsia lineage have been observed in respect of serotype O. [ABSTRACT FROM AUTHOR]

This paper describes a new species of Clavicipitaceae fungi belonging to the genus Metacordyceps G.H. Sung, J.M. Sung, Hywel-Jones & Spatafora, defined as Metacordyceps dhauladharensis sp. nov., from India. The diagnostic features of this new species are stipitate stromata of brownish color and an elongated fertile head on a Hymenopteran host. The perithecium size of this species was measured as 152-257 x 65-72 µm, and the asci were measured as 30-48 µm in length and 2.5 µm in breadth. Based on molecular studies, the sequence of 469 bp of this species showed only 86% homology with Metacordyceps indigotica (Kobayasi & Shimizu) Kepler, G.H. Sung & Spatafora. [ABSTRACT FROM AUTHOR]

In this study a new species of nematode, Iheringascaris goai n. sp., is reported from two fish hosts, including silver whiting, Sillago sihama, and spotted catfish, Arius maculatus, caught off the Central West Coast of India at Goa. The new species can be differentiated morphologically from I. inquies, the most closely related species collected from cohabiting marine fish. The distinguishing characteristics are distinct cuticular striations, a unilateral excretory system, the presence of dentigerous ridges on the inner margin of the lips and the ratio of oesophagus to body length. In males, the ratio of spicules to body length is higher and the number of pre-anal papillae is less in comparison to those in I. inquies. In addition, the tail curves ventrad in males, while in females, the vulva is post-equatorial. The sequence alignment of 18S rDNA and cytochrome c oxidase subunit I with sequences of known species selected from the same superfamily shows a significant difference. The morphological and molecular differences reported here can, therefore, be used to assign the specimen to a new species. [ABSTRACT FROM AUTHOR]

The article presents a study on the white spot syndrome virus (WSSV) infection in the new host mud crab and the penaeid shrimp. It says that crab samples were gathered from a farm in south India and fed with trash fish at a 10% biomass rate, which resulted to white spots seen on the inner surface of moribund and dead crabs. It mentions that infected crabs were fed into shrimps that showed white spots inside the carapace after ingestion. Moreover, oral and ingestion routes are discussed.

Background: Among human host factors known to modulate HIV disease progression, the C-type lectins, dendritic cell-specific intercellular adhesion molecule-3-grabbing non-integrin, DC-SIGN and the liver/lymph node-specific L-SIGN have been poorly described in children with HIV. We aimed to study the exon 4 repeat-region polymorphisms, and assess the impact of DC/L-SIGN homozygous and heterozygous genotypes among pediatric slow and rapid progressors. Methods & Materials: We defined slow progressor children as perinatally-infected, asymptomatic, with known HIV infection for >10yrs, ART-naïve, and CD4>500 cells/mm³ and rapid/normal progressors as HIV infection<10 years, on ART, CD4<500 cells/mm³. Genomic DNA isolated from whole blood was genotyped for DC/LSIGN exon 4 tandem repeat-region variants by PCR. Results: Among 25 slow progressors included, mean age was 10.8±2.42 years, 64% females, median CD4 count was 751 cells/mm³ (IQR 575-1036.75) and viral load, 4.36 log copies/ml (IQR 4.09-4.84). Among 40 rapid progressors, mean age was 6.07±2.4 years, 45% females, median CD4 was 462.5 cells/mm³ (IQR 291- 663) and viral load, 5.42 log copies/ml (IQR 4.97-5.95). The exon-4 repeat-region DC-SIGN polymorphism was not observed in our population as all samples showed 7/7 homozygous DC-SIGN genotype. In the L-SIGN repeat region, eight genotypes were found. The total L-SIGN heterozygosity in slow (7/5, 7/6, 9/5, 9/6 and 9/7 genotypes) and rapid (6/5, 7/5, 7/6, 9/5, 9/6 and 9/7 genotypes) progressors was 76% and 45% respectively (P=0.02; OR=3.87; 95%CI 1.3-11.7). Rapid progressors had a significantly higher occurance of 7/7 homozygous L-SIGN genotype (P=0.03; OR=3.5; 95%CI=1.16- 10.6). The L-SIGN allele frequency in slow progressors was 14% for allele 5, 14% for allele 6, 54% for allele 7 and 18% for allele 9. L-SIGN alleles 6 and 7 were significantly more frequent in rapid progressors than slow progressors (P=0.03, OR=0.16, 95%CI=0.03-0.8 and P=0.03, OR=2.24, 95%CI=1.07-4.72 respectively). Conclusion: This is the first study to determine the DC-SIGN and L-SIGN polymorphisms in HIV-1 positive children in India. While heterozygous DC-SIGN genotypes were not seen in this population, the higher prevalence of heterozygous L-SIGN genotypes among slow progressors suggests their protective role in HIV disease progression among children in India. [ABSTRACT FROM AUTHOR]

In this article, we document the first complete genome sequence of an isolate of bluetongue virus serotype 16 (BTV16) from a goat in India. The virus was isolated from an in-contact goat from an animal farm in Chennai where clinical disease occurs in sheep. The total size of the genome is 19,185 bp. The information provided for full-length sequences of all 10 segments will help in understanding the geographical origin and transmission of the Indian isolate of BTV16 as well as its comparison with global isolates of BTV16 of sheep, cattle, and other host species origins. [ABSTRACT FROM AUTHOR]