CALLUS INDUCTION, PHYTOCHEMICAL STUDIES AND ANTIBACTERIAL ACTIVITY OF DECALEPIS ARAYALPATHRA (JOSEPH AND CHANDRAS) VENTER

Objective: The aim of the present study was designed for the induction of callus from leaf explants of Decalepis arayalpathra (D. arayalpathra) and to analyse their phytochemical constituents and antibacterial activity.Methods: The explants were cultured on Murashige and Skoog (MS) medium supplemented with different concentration of 2, 4-dichlorophenoxyacetic acid (2, 4-D) and later subcultured to the combination of 6-benzylaminopurine (BAP) and 1-naphthaleneacetic acid (NAA). The phytochemical constituents were analysed in the different solvent extracts using standard methods. Antibacterial activity of the different solvent extracts was carried out using agar well diffusion method against reference standards. Results: Callus induction was observed on MS medium supplemented with different concentration and combination of auxins and cytokinins. Maximum callus induction was noticed on media supplemented with 2, 4-D (2 mg/l) and BAP (1 mg/l)+NAA (0.5 mg/l) respectively. The phytochemical screening revealed the presence of alkaloids, flavonoids, phenols, tannins, steroids and terpenoids, glycosides, coumarins and quinone etc. All the solvent extracts showed varying degree of antibacterial activities against the bacterial strains (Bacillus subtilis, Escherichia coli, Klebsiella pneumoniae, Pseudomonas fluorescence and Staphylococcus aureus). The maximum antibacterial activity of leaf was observed in aqueous (Klebsiella pneumoniae, 19.00±1.00) and methanolic extract (Klebsiella pneumoniae, 18.33±1.15). Whereas petroleum ether extract of the callus showed maximum inhibition (Bacillus subtilis, 17.00±1.00) compare to other extracts.Conclusion: The study revealed the presence of secondary metabolites in the leaf and callus extracts of D. arayalpathra. The methanolic extracts possess higher antibacterial activity compared to other solvent extracts. However, further studies have to be carried out for the isolation and identification of antimicrobial compounds against pathogens

5-Bromo­pyrimidin-2(1H)-one

The geometric parameters of the title compound, C4H3BrN2O, are in the usual ranges. The crystal packing is characterized by N—H⋯N and C—H⋯O hydrogen bonds and short O⋯Br contacts

1-(3-Bromo-2-thien­yl)ethanone

In the title compound, C6H5BrOS, the non-H and aromatic H atoms lie on a crystallographic mirror plane. In the crystal, mol­ecules are linked into chains propagating along the c axis by inter­molecular C—H⋯O hydrogen bonds

Ethyl 4-(3-bromo-2-thien­yl)-2-oxo-6-phenyl­cyclo­hex-3-ene-1-carboxyl­ate

The title compound, C19H17BrO3S, crystallizes with two mol­ecules in the asymmetric unit. The methyl group of one mol­ecule is disordered approximately equally over two positions. The dihedral angles between the thio­phene and phenyl groups are 68.5 (2) and 67.5 (2)° in the two mol­ecules

Yield loss Modeling for late Leafspot and Rust in Groundnut

Late leaf spot and rust diseases occur together and cause considerable yield loss in groundnut. Cultivation of resistant varieties is the best strategy to stabilize productivity under disease epidemics. Several varieties resistant or moderately resistant to LLS and rust have been developed in groundnut, but most of them differ in yield loss even at the same level of disease due to complex interrelationships between disease and yield loss. Crop loss models have been employed to gain insight into these relations and to plan sound breeding strategies. In the present study, different empirical models were tested for their explanatory value for yield loss among 10 groundnut genotypes with varying level of resistance to late !eafspot and/or rust. Towards yield loss modeling, disease severity at different growth stages and physiological traits viz., leaf area index (LAI), harvest index (HI), healthy leaf area duration (HAD), crop and pod growth rates(CGR and PGR) and partitioning coefficient (PC) were considered as independent variables, while yield loss as dependent variable in regression models. Single pOint models based on disease did not explain the variation in loss completely, but revealed pOd fill ing as the critical stage in determining yield loss. Multiple point models using disease at different stages marginally improved the explanatory value; Inclusion of physiological traits in stepwise regression models improved the R2 considerably, revealing their relevance to yield loss. Yield loss varied significantly among the genotypes resistant to both LLS and rust (9-17%), moderately resistant to LLS or rust (18-26%) and susceptible to LLS and rust (30-42%). Resistant genotype, GPBD-4 had high yield potential with minimum yield reduction due to Its high partitioning efficiency and pod growth rate. Though highly susceptible, TAG-24 showed tolerance by early cessation of vegetative growth and efficient translocation of photosynthates to pOds leading to high harvest index

'Asking the right question'. A comparison of two approaches to gathering data on 'herbals' use in survey based studies

BACKGROUND:Over the last decade academic interest in the prevalence and nature of herbal medicines use by pregnant women has increased significantly. Such data are usually collected by means of an administered questionnaire survey, however a key methodological limitation using this approach is the need to clearly define the scope of 'herbals' to be investigated. The majority of published studies in this area neither define 'herbals' nor provide a detailed checklist naming specific 'herbals' and CAM modalities, which limits inter-study comparison, generalisability and the potential for meta-analyses. The aim of this study was to compare the self-reported use of herbs, herbal medicines and herbal products using two different approaches implemented in succession. METHODS:Cross-sectional questionnaire surveys of women attending for their mid-trimester scan or attending the postnatal unit following live birth at the Royal Aberdeen Maternity Hospital, North-East Scotland. The questionnaire utilised two approaches to collect data on 'herbals' use, a single closed yes/no answer to the question "have you used herbs, herbal medicines and herbal products in the last three months"; and a request to tick which of a list of 40 'herbals' they had used in the same time period. RESULTS:A total of 889 responses were obtained of which 4.3% (38) answered 'yes' to herbal use via the closed question. However, using the checklist 39% (350) of respondents reported the use of one or more specific 'herbals' (p<0.0001). The 312 respondents who reported 'no' to 'herbals' use via the closed question but "yes" via the checklist consumed a total of 20 different 'herbals' (median 1, interquartile range 1-2, range 1-6). CONCLUSIONS:This study demonstrates that the use of a single closed question asking about the use of 'herbals', as frequently reported in published studies, may not yield valid data resulting in a gross underestimation of actual use

Pregnancy, prescription medicines and the potential risk of herb-drug interactions:a cross-sectional survey

Funding All funding was from institutional resource. JSM, AS are employed by the University of Aberdeen. DS is employed by the Robert Gordon University. BP and CR are employed by NHS Scotland. ARP and MAH are employed by the Hamad Medical Corporation. Qatar. NI is a postgraduate student at the University of Aberdeen.Peer reviewedPublisher PD

CALLUS INDUCTION, PHYTOCHEMICAL STUDIES AND ANTIBACTERIAL ACTIVITY OF DECALEPIS ARAYALPATHRA (JOSEPH AND CHANDRAS) VENTER

Objective: The aim of the present study was designed for the induction of callus from leaf explants of Decalepis arayalpathra (D. arayalpathra) and to analyse their phytochemical constituents and antibacterial activity.Methods: The explants were cultured on Murashige and Skoog (MS) medium supplemented with different concentration of 2, 4-dichlorophenoxyacetic acid (2, 4-D) and later subcultured to the combination of 6-benzylaminopurine (BAP) and 1-naphthaleneacetic acid (NAA). The phytochemical constituents were analysed in the different solvent extracts using standard methods. Antibacterial activity of the different solvent extracts was carried out using agar well diffusion method against reference standards. Results: Callus induction was observed on MS medium supplemented with different concentration and combination of auxins and cytokinins. Maximum callus induction was noticed on media supplemented with 2, 4-D (2 mg/l) and BAP (1 mg/l)+NAA (0.5 mg/l) respectively. The phytochemical screening revealed the presence of alkaloids, flavonoids, phenols, tannins, steroids and terpenoids, glycosides, coumarins and quinone etc. All the solvent extracts showed varying degree of antibacterial activities against the bacterial strains (Bacillus subtilis, Escherichia coli, Klebsiella pneumoniae, Pseudomonas fluorescence and Staphylococcus aureus). The maximum antibacterial activity of leaf was observed in aqueous (Klebsiella pneumoniae, 19.00±1.00) and methanolic extract (Klebsiella pneumoniae, 18.33±1.15). Whereas petroleum ether extract of the callus showed maximum inhibition (Bacillus subtilis, 17.00±1.00) compare to other extracts.Conclusion: The study revealed the presence of secondary metabolites in the leaf and callus extracts of D. arayalpathra. The methanolic extracts possess higher antibacterial activity compared to other solvent extracts. However, further studies have to be carried out for the isolation and identification of antimicrobial compounds against pathogens

Genetic programming based models in plant tissue culture: An addendum to traditional statistical approach.

In this paper, we compared the efficacy of observation based modeling approach using a genetic algorithm with the regular statistical analysis as an alternative methodology in plant research. Preliminary experimental data on in vitro rooting was taken for this study with an aim to understand the effect of charcoal and naphthalene acetic acid (NAA) on successful rooting and also to optimize the two variables for maximum result. Observation-based modelling, as well as traditional approach, could identify NAA as a critical factor in rooting of the plantlets under the experimental conditions employed. Symbolic regression analysis using the software deployed here optimised the treatments studied and was successful in identifying the complex non-linear interaction among the variables, with minimalistic preliminary data. The presence of charcoal in the culture medium has a significant impact on root generation by reducing basal callus mass formation. Such an approach is advantageous for establishing in vitro culture protocols as these models will have significant potential for saving time and expenditure in plant tissue culture laboratories, and it further reduces the need for specialised background

Not Available

Not AvailableAs a part of long term study on fertigation in arecanut (Areca catechu L.) initiated in 1996 at Central Plantation Crops Research Institute, Regional Station, Vittal in Karnataka, an experiment was conducted in 1999 to study the effect offertigation comprising of different fertilizer doses and frequencies of application on the distribution pattern of available phosphorus and potassium in soil. The available P and K distribution in soil was significantly affected by both depth and distance from dripping point. The concentration of both available P and K was maximum at the dripping point within 30 ern depth. The available P and K content were the highest at the dripping point and declined progressively with distance from dripping point. Nutrient distribution pattern showed that both 50 % and 100%NPK levels maintained more or less same available phosphorus and potassium concentration in arecanut rhizosphere. This study gives scope for reducing the fertilizer dose if applied through drip irrigation on long term basis.Not Availabl