Growth Enhancement of Chickpea in Saline Soils Using Plant Growth-Promoting Rhizobacteria

Bacterial isolates with the ability to tolerate salinity and plant growth-promoting features were isolated from the saline areas of Gujarat, India, that is, Bhavnagar and Khambat. A total of 176 strains of rhizobacteria were isolated out of which 62 bacterial strains were able to tolerate 1 M NaCl. These were then further studied for their potential plant growth-promoting rhizobacteria characteristics like phosphate solubilization, siderophore production, and IAA production. Twenty-eight isolates of the 62 strains showed good tricalcium phosphate solubilization in solid medium in the range of 9–22 mm and 15 isolates showed good phosphate solubilization in liquid medium in the range of 9–45 μg/ml. Siderophore production was checked in all 15 isolates, and 13 were screened out that produced the hydroxamate type of siderophore in the range of 11–50 mM. Among the 13 isolates, 10 were able to produce indole acetic acid in the range of 10–26 μg/ml after 72 h of incubation. Pot trials were carried out on chickpea under 300 mM NaCl stress using the best five isolates. Plants inoculated with MSC1 or MSC4 isolates showed an increase in the parameters that evaluate plant growth when compared to uninoculated controls. Strains MSC1 and MSC4 were identified as Pseudomonas putida and Pseudomonas pseudoalcaligens, respectively, according to sequence analysis of the 16S rRNA gene.     

Optimization of xylanase production using inexpensive agro-residues by alkalophilic Bacillus subtilis ASH in solid-state fermentation

Alkalophilic Bacillus subtilis ASH produced high levels of xylanase using easily available inexpensive agricultural waste residues such as wheat bran, wheat straw, rice husk, sawdust, gram bran, groundnut and maize bran in solid-state fermentation (SSF). Among these, wheat bran was found to be best substrate. Xylanase production was highest after 72 h of incubation at 37 °C and at a substrate to moisture ratio of 1:2 (w/v). The inoculum level of 15% resulted in maximum production of xylanase. The enzyme production was stimulated by the addition of nutrients such as yeast extract, peptone and beef extract. In contrast, addition of glucose and xylose repressed the production of xylanase. The extent of repression by glucose (10%, w/v) was 81% and it was concentration-dependent. Supplementation of the medium with 4% xylose caused 59% repression. Under optimized conditions, xylanase production in SSF (8,964 U of xylanase/g dry wheat bran) was about twofold greater than in submerged fermentation. Thus, B. subtilis produced a very high level of xylanase in SSF using inexpensive agro-residues, a level which is much higher than that reported by any other bacterial isolate. Furthermore, the enzyme was produced at room temperature and with tap water without the addition of any mineral salt in SSF, leading to a marked decrease in the cost of xylanase production, which enhances its industrial potential.     

Phenotypic Switching in Biofilm-Forming Marine Bacterium Paenibacillus lautus NE3B01

Biofilm-forming marine bacterium Paenibacillus lautus NE3B01 was isolated from a mangrove ecosystem, Odisha, India. This isolate formed a swarming type of colony pattern on the solid culture medium with 0.5–2 % agar. Phase contrast microscopy study of a growing colony of P. lautus on solid media and swarming pattern revealed the existence of two phenotypically distinct cells (i.e. cocci and rods) across the colonies. However, in actively growing planktonic culture, only rod-shaped cells were observed. Biofilm growth studies (crystal violet assay) with the isolate showed significant biofilm formation by 6 h, and the detachment phase was observed after 18 h. Biofilm parameters (such as total biomass, roughness coefficient, biofilm thickness, etc.) of 24-h-old P. lautus biofilm were studied by confocal scanning laser microscopy (CSLM). The CSLM study showed that P. lautus formed a biofilm with an average thickness of 14.8 ± 2.6 μm, a high roughness coefficient (0.379 ± 0.103) and surface to bio-volume ratio (4.59 ± 1.12 μm²/μm³), indicating a highly uneven topography of the biofilm. This also indicates that the 24-h-old biofilm is in dispersal phase. Scanning electron microphotographs of P. lautus also supported the existence of two distinct phenotypes of P. lautus. The current findings suggest that P. lautus has two vegetative phenotypes and to decongest the overcrowded biofilm the bacterium can switch over to motile rods from nonmotile cocci and vice versa.     

Alcohol dehydrogenase of Biomphalaria glabrata (Mollusca: Pulmonata): Polymorphism,genetic analysis,and interspecific variations

Alcohol dehydrogenase of Biomphalaria glabrata has been characterized by electrophoresis, substrate specificities, and other physicochemical means. It exists as a multiple molecular form possessing a minimum number of three bands in ovotestis, five in digestive gland, and six in albumen gland. Each organ shows characteristic electrophoretic forms which differ in substrate specificities and the response to the organomercurial inhibitor p-hydroxymercuribenzoate. Mercaptoethanol treatment has no effect on any electrophoretic form. Genetic analyses of the electrophoretic variants show that three different loci are responsible for the synthesis of the various electrophoretic forms observed in this species. Different species vary in their electrophoretic patterns. A possible role of alcohol dehydrogenase isozymes in the phylogenetic relationship among three species, B. glabrata, B. tenagophila, and B. straminea, has been discussed.This work was supported by a grant from the Conselho Nacional de Pesquisas, Brazil.     

In Vitro Clonal Propagation and Medium Term Conservation of Brahmi [Bacopa monnieri (L) Wettst]

A protocol has been developed for in vitro clonal propagation leading to conservation of Bacopa monnieri (L) Wettst, a medicinal plant of high commercial potential with legendary reputation as a memory vitalizer. Single node explants when cultured on Murashige and Skoog’s medium supplemented with BA (0.2 mg l^-1), showed active shoot proliferation (22.2 shoots/ explant in 8 weeks) without callus formation. Rooting was achieved on the same medium. The generated shoots could also be conserved for 12 months with high survival rate (up to 100%). The regenerants upon transfer to soil showed no morphological variation as compared with the donor plants. The medium optimized in the present study was applied for culture establishment and conservation of a total of 15 Brahmi accessions procured from different regions.     

Is Private Health Care the Answer to the Health Problems of the World's Poor?

Background to the debate: The global burden of disease falls disproportionately upon the world''s low-income countries, which are often struggling with weak health systems. Both the public and private sector deliver health care in these countries, but the appropriate role for each of these sectors in health system strengthening remains controversial. This debate examines whether the private sector should step up its involvement in the health systems of low-income countries.     

Behavioural and psychological symptoms of dementia in primary care: a survey of general practitioners in Ireland

Background Management of neuropsychiatric symptoms is a challenging task in primary care. Aims To assess self-reported confidence and knowledge of general practitioners (GPs) regarding the identification and management of behavioural and psychological symptoms of dementia (BPSD).Methods A self-designed two-page paper questionnaire was sent to a random sample of 160 GPs practising in north Dublin. They were asked to evaluate their confidence and knowledge on several aspects of diagnosis and management of BPSD.Results Completed questionnaires were returned from 109 GPs (response rate = 68%), of which 106 were usable. In general, GPs were somewhat critical of their self-reported skills in diagnosing (76.4%) and managing (77.4%) BPSD, as well as in discriminating BPSD from other behavioural disturbances (71.7%). Many of them (67.9%) also encountered difficulty accessing specialist services. There was no correlation between demographic characteristics of GPs or patient caseload with respect to their responses to questionnaire items. Although many GPs (92.5%) highly valued the important role of non-pharmacological interventions in BPSD, none of them reported recommending these in their daily practice.Conclusions Despite the fact that GPs have a wealth of knowledge about BPSD, they are largely critical of their knowledge and management skills of these symptoms. Efforts should be focused on supporting GPs by means of educational interventions that consider all aspects of dementia, but additionally highlight the more challenging neuropsychiatric components of the illness. Health services need to be structured in a way that promotes collaboration between GPs and mental health professionals for a seamless delivery of care.