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The present study reports a high frequency in vitro propagation protocol through apical bud sprouting and basal organogenic nodule formation in shoot tip explants of Decalepis hamiltonii, an endemic and endangered medicinal liana. Among different combinations of plant growth regulators (PGRs) and growth additives, maximum of 8.20 shoots per explant with mean shoot length of 6.54 cm were induced on Murashige and Skoog’s medium (MS) supplemented with 5.0 µM 6-benzyladenine (BA) + 0.5 µM indole-3-acetic acid (IAA) + 30.0 µM adenine sulphate (ADS) through apical bud sprouting. On single cytokinin treatment explants did not exhibit good multiplication but showed nodulation (N₁) from the basal cut end similar to cytokinin–auxin combination (N₂). Between two types of nodular tissues, N₂ was proved to be better for maximum shoot regeneration (15.40 shoots per explant) and shoot length (4.56 cm) when cultured on MS medium supplemented with 5.0 µM BA, 0.5 µM IAA, 30.0 µM ADS and 1.0 µM gibberellic acid (GA₃). Microshoots were efficiently rooted on half-strength MS medium supplemented with 2.5 µM α-naphthalene acetic acid (NAA). After successful acclimatization in Soilrite, 95.10 % plantlets were survived in field conditions. Histological investigation proved useful in ascertaining the callogenic nature of the regenerating nodular tissue formed at the basal cut end of shoot tip explant. Acclimatized plantlets were studied for the estimation of chlorophyll and carotenoid content as well as the net photosynthetic rate (PN) during subsequent days of transfer to ex vitro condition. Moreover, acclimatization had a significant effect on biomass production and the synthesis of 2-hydroxy-4-methoxy benzaldehyde (2HMB). Maximum fresh weight (3.78 gm/plant), dry weight (0.39 gm/plant) of roots and 2HMB content (15.94 µg/ml of extract) were noticed after 8 weeks of acclimatization.
One of the fundamental aspects in understanding the biology, diversity and epidemiology of a parasite lies in its proper identification. In the present study, morphological and molecular characterization of Clinostomum metacercariae recovered from an ornamental fish, Trichogaster fasciata, was carried out in order to ascertain its identity. To serve the purpose, scanning electron micrographs and gene sequences for two commonly used molecular markers, i.e., nuclear ribosomal internal transcribed spacer 2 (rDNA-ITS2) and mitochondrial cytochrome c oxidase subunit 1 (mtCO1) were obtained. The sequences were further used for generating similarity index matrix as well as inferring phylogenies. Light and electron microscopic observations on metacercariae of the parasite revealed that it belongs to the genus Clinostomum. Identification of the same up to the level of species was made possible through sequence and phylogenetic analyses. The ITS2 sequence analyses of our species (KX758630) showed similarity to unidentified Clinostomum sp. reported from Nigeria (KY865625) and China (KP110579), and C. tilapiae recorded from South Africa (KX034048) and Nigeria (KY649353). However, the CO1 gene analyses suggested it to be highly identical to C. philippinense and the same was also corroborated in the phylogenetic analysis. Thus, morphological and molecular characterization revealed that the recovered metacercariae belong to the species C. philippinense. Additionally, a brief description of secondary structures of ITS2 of various species of Clinostomum has also been discussed.
Some parts of the Indian Himalayan region are covered by established and abandoned tea bushes. Rhizospheric soils of these plants were studied for bacterial dominance and antagonism. Representatives of Bacillus and Pseudomonas genera were found to dominate the rhizosphere of established and abandoned tea bushes, respectively. Amongst the isolated species Bacillus subtilis and Bacillus mycoides appeared to be closely associated with roots of established tea bushes while the rhizosphere of abandoned tea bushes was dominated by Pseudomonas putida. Four isolates of both B. subtilis and P. putida were selected on the basis of maximum antibacterial activity. The bacteriocin-like activity of B. subtilis and P. putida strains was detected to be active over a range of temperature 0-50°C and was sensitive to proteolytic enzymes. Incubation of indicator strains with different concentrations of bacteriocin-like substances confirmed their bactericidal activity. Various species of Bacillus and Pseudomonas behaved antagonistically amongst themselves due to the production of bacteriocins under in vitro conditions.
Female white-footed mice Peromyscus leucopus (Rafmesque, 1818) and their dependent offspring were monitored in nest boxes to determine the extent and causes of nest mortality. The mortality of dependent young was high (561 of 838; 66%) and variable among years. Most mortality involved the loss of entire litters (112 of 183 litters; 61%), with half of these losses attributed to the death of lactating females before the young were weaned (59 of 112 litters; 53%). Most mortality was from unknown causes, although infanticide, energetic constraints and prédation were identified in a small number of cases. Prédation is likely the major source of mortality in this population.
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