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Rhododendron wattii Cowan is a rare and endangered plant found in northeast India. In an effort to boost specimen numbers, experiments of in vitro seed germination, shoot induction on different media supplemented with the cytokinin isopentenyladenine (2iP), and root induction with auxins α-naphthaleneacetic acid (NAA), indole-3-butyric acid (IBA) and indole-3-acetic acid (IAA) in woody plant medium (WPM) were carried out. A maximum mean shoot number of 7.72 per explant were obtained from nodal explants cultured on WPM and 39.36 μM 2iP with a maximum mean shoot length of 2.30 cm per explant. Among the auxins investigated for root induction, IBA at 2.45 μM was found to produce the most and the longest roots, when compared to other treatments. However, WPM supplemented with 0.2% (w/v) activated charcoal also showed 100% root formation with shoots having broader leaves compared to auxin treatments. About 60% of in vitro rooted plantlets transferred from lab to greenhouse conditions survived. Sixty acclimatized plants were reintroduced in the vicinity of their natural habitat at Naga Heritage Village, Kisama, Nagaland, in May 2016 for ex situ conservation. Survival of the reintroduced plants was confirmed during the field visit conducted in November 2016. [ABSTRACT FROM AUTHOR]

Bacillus thuringiensis isolates were characterized in rhizospheric cotton soils by using acetate selection process from eight different locations in South India. The fact that B. thuringiensis indices were higher in proportion in soil samples taken from Tamil Nadu and Karnataka than from Andhra Pradesh, indicates the abundance of B. thuringiensis populations in the cotton rhizosphere. Biochemical typing of the isolates designated eight local isolates (BtNg13, BtCo1, BtHyb7, BtAm2, BtRm5, BtWr3, BtPl 4, BtN 9), which belong to subspecies kurstaki, the most prevalent subspecies. Toxicity assays on American boll worm larval ( F) populations collected from the Andhra Pradesh, Bangalore and Coimbatore regions, with a susceptible insect strain against different isolates of B. thuringiensis kurstaki spore-crystal mix, revealed distinct susceptibility patterns and specificity. The highest susceptibility was observed in the F populations of Coimbatore, followed by Bangalore and Hyderabad populations, in comparison with the susceptible insect strain. Significant differences were observed ( p < 0.0005 and CD = 5.3975) among Btk local isolates, H. armigera biotypes, Btk spore-crystal mix concentration and their interactions, through the Multifactorial ANOVA analysis. The toxicity of local B. thuringiensis isolates was higher than that of HD-1 (reference B.t.k strain). Indigenous Btk isolates have an enormous potential for the management of H. armigera in terms of development of resistance to HD-1. The present study would serve as a baseline data for future resistance monitoring of B. thuringiensis strains in H. armigera in Southern India. (© 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [ABSTRACT FROM AUTHOR]