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• Heavy metal tolerant and PGPR rhizobacteria (Bacillus cereus, Bacillus safensis, Bacillus pumilus, Serratia marcescens, Lelliottia amnigena, Pseudomonas koreensis and Klebsiella variicola) isolated from Musa rhizosphere growing in coal mining area. • Inoculation of the PGPR consortia in the Brassica sp. and Helianthus annuus growing in Cd/Cu contaminated soil has improved its tolerance to these heavy metals over the control. • PGPR can be used for the bioremediation of the contaminated soil. In soils polluted with heavy metals, plant growth promoting rhizobacteria (PGPR) with heavy metal tolerance can aid plants to adapt to heavy metal contaminated conditions. Heavy metal tolerant rhizobacteria were isolated from Musa rhizosphere growing the Tsurang Riverbank, Nagaland, India, a coal mining area. A total of 26 bacterial isolates/strains were tested for heavy metals and salt tolerance and some growth-promoting traits like IAA, siderophore production and phosphate solubilisation. Of the 26 strains, 7 strains (TSU1, TSU11, TSU12, TSU3, TSU4, TSU7, and TSU8) supported better plant growth. Different isolates displayed variable heavy metal tolerance (30 to 8070 μg/ml). Strains TSU8 and TSU4 exhibited the highest salt tolerance (12 %). Based on the 16S rRNA sequencing, the isolates were identified as TSU3 (Bacillus cereus) (OQ547230), TSU4 (Bacillus safensis) (OQ547231), TSU8 (Bacillus pumilus) (OQ547232), TSU11 (Klebsiella variicola) (OQ947091), TSU12 (Lelliottia amnigena) (OQ947097), TSU7 (Pseudomonas koreensis) (OQ947088) and TSU1 (Serratia marcescens) (OQ726408). A successful consortium of bacterial isolates was formulated and inoculated on Brassica juncea and Helianthus annuus with heavy metal Cd/Cu (150 µgml−1) in the potted soil. This consortium improved growth performance significantly in both fresh and dry weight basis. In B. juncea, enhancement in root length and weight were recorded by 53 and 93 % respectively against control, while, fresh weight of shoot was improved by 72 % on soil adjunct with PGPR and 67 % with PGPR in heavy metal contaminated condition. Similar trend was also registered on dry weight basis. Whereas, PGPR consortia treated H. annuus registered increased shoot and root lengths both fresh and dry weight basis. This consortium with these seven bacterial isolates may contribute to microbe assisted phytoremediation under heavy metal polluted area. [ABSTRACT FROM AUTHOR]

Nagaland has a rich macro fungal flora but not many works has been carried out till today. Present investigation deals with molecular characterization and phylogenetic analysis of six popular wild edible mushrooms (WEMs) species of Nagaland, India viz., Lentinula edodes, Lentinus squarrosulus, L. sajor-caju, L. tigrinus, Schizophyllum commune, Termitomyces heimii and one variety of L. squarrosulus based on molecular markers (ITS, 18S rRNA and 28S rRNA genes) data. The use of DNA markers for identification of mushrooms is highly desirable and practical because it is reliable and quick. This approach could resolve successfully the identity and interrelationship of six WEM species with respect to their infrageneric groups. The high CI values of the mushrooms species indicated the low homoplasy nature. The ITS and 28S rRNA data sets were found to be more informative then the 18S rRNA datasets. The molecular data generated for each mushroom species in the present investigation will help in correct identification and conservation of these widely consumed WEM of the region. Additionally assessment of bioactive molecules indicates that studied species are rich in pro-health bioactive compounds. The study hence throws light on the potential and importance of mushrooms especially the edible mushrooms as an economically valuable crop.

Adventitious shoot buds formation from axillary buds of nodal segments of S. flaccidifolious was achieved on MS medium containing sucrose (3%, w/v), and a-naphthalene acetic acid (NAA; 3 microM) and benzyl adenine (3 microM) in combination. The nodal segments were primed on 'Growtak Sieve' for 48 h on MS medium containing sucrose (2%), polyvinyl pyrollidone (200 mgL(-1)) as antioxidant. About 80% of primed nodal segments responded positively and formed approximately 12 adventitious shoot buds per explants from explants collected during October-November months of every year. The shoot buds converted into plantlets on MS medium containing sucrose (3%) and kinetin (3 microM) where approximately 7 micro shoots developed per subculture after 8 weeks of culture. The regenerated micro shoots induced average 14 roots/plant on medium containing NAA (3 microM). The regenerates were hardened for 6-7 weeks on medium with 1/2MS salt solution and sucrose (2%) under normal laboratory condition before transferring to potting mix. About 70% transplants survived after two months of transfer.