Detection of nif genes in nitrogen-fixing bacterial isolate from tomato (Lycopersicon esculentum Mill cv Pusa ruby)

Nitrogen-fixing bacterial isolate from the intercellular spaces of tomato root cortical cells was studied for the location of nif genes on the chromosomal or plasmid DNA. The bacterial isolate showed two plasmids of approximate molecular sizes of 220 and 120 kb. Klebsiella pneumoniae nif HDK probe hybridized with the chromosomal DNA and not with the plasmid DNA thereby showing that nif genes are localised on the chromosomal DNA.

Features of a unique intronless cluster of class I small heat shock protein genes in tandem with box C/D snoRNA genes on chromosome 6 in tomato (Solanum lycopersicum)

Physical clustering of genes has been shown in plants; however, little is known about gene clusters that have different functions, particularly those expressed in the tomato fruit. A class I 17.6 small heat shock protein (Sl17.6 shsp) gene was cloned and used as a probe to screen a tomato (Solanum lycopersicum) genomic library. An 8.3-kb genomic fragment was isolated and its DNA sequence determined. Analysis of the genomic fragment identified intronless open reading frames of three class I shsp genes (Sl17.6, Sl20.0, and Sl20.1), the Sl17.6 gene flanked by Sl20.1 and Sl20.0, with complete 5' and 3' UTRs. Upstream of the Sl20.0 shsp, and within the shsp gene cluster, resides a box C/D snoRNA cluster made of SlsnoR12.1 and SlU24a. Characteristic C and D, and C' and D', boxes are conserved in SlsnoR12.1 and SlU24a while the upstream flanking region of SlsnoR12.1 carries TATA box 1, homol-E and homol-D box-like cis sequences, TM6 promoter, and an uncharacterized tomato EST. Molecular phylogenetic analysis revealed that this particular arrangement of shsps is conserved in tomato genome but is distinct from other species. The intronless genomic sequence is decorated with cis elements previously shown to be responsive to cues from plant hormones, dehydration, cold, heat, and MYC/MYB and WRKY71 transcription factors. Chromosomal mapping localized the tomato genomic sequence on the short arm of chromosome 6 in the introgression line (IL) 6-3. Quantitative polymerase chain reaction analysis of gene cluster members revealed differential expression during ripening of tomato fruit, and relatively different abundances in other plant parts.

Herbal medicines used in the treatment of diabetes mellitus in Arunachal Himalaya, northeast, India

Ethnopharmacological relevance: Medicinal plants have played an important role in treating and preventing a variety of diseases throughout the world. Khampti tribal people living in the far-flung Lohit district of the Eastern Arunachal Himalaya, India still depend on medicinal plants and most of them have a general knowledge of medicinal plants which are used for treating a variety of ailments. This survey was undertaken in Lohit district in order to inventory the medicinal plants used in folk medicine to treat diabetes mellitus. Materials and methods: Field investigations were conducted in seventeen remote villages of Lohit district starting from April 2002 to May 2004 through interviews among 251 key informants who were selected randomly during our household survey. To elucidate community domains and determine differences in indigenous traditional knowledge of medicinal plants with anti-diabetic efficacy, we repeated our field survey starting from April 2008 to May 2010 with one hundred traditional healers locally called as ``Chau ya'' in Khampti of Lohit district. ``Chau ya'' traditional healers who know and use medicinal plants for treating diabetes mellitus were interviewed using a semi-structured questionnaire. Results: This study reports an ethnobotanical survey of medicinal plants in Lohit district of Arunachal Pradesh reputed for the treatment of diabetes mellitus. Forty-six plant species were identified in the study area to treat diabetes mellitus by the Khamptis ``Chau ya'' traditional healers. Comparative published literature survey analysis of this study with other ethnobotanical surveys of plants used traditionally in treating diabetes mellitus suggests that eleven plant species make claims of new reports on antidiabetic efficacy. These plant species are Begonia roxburghii, Calamus tenuis, Callicarpa arborea, Cuscuta reflexa, Dillenia indica, Diplazium esculentum, Lectuca gracilis, Millingtonia hortensis, Oxalis griffithii, Saccharum spontaneum, and Solanum viarum. Some of the plants reported in this study have an antidiabetic effect on rodent models but none have sufficient clinical evidence of effectiveness. Conclusions: The wide variety of medicinal plants that are used to treat diabetes mellitus in this area supports the importance of plants in the primary healthcare system of the rural people of Lohit district of Arunachal Pradesh. The finding of new plant uses in the current study reveals the importance of the documentation of such ethnobotanical knowledge. (C) 2012 Elsevier Ireland Ltd. All rights reserved.