ABSTRACT
Aim: The study was to evaluate the phytogenic chemical compounds and Antifungal Activity of essential oil from roots of Selinum vaginatum C.B. Clarke, growing in the Himalayan region of Jammu & Kashmir. Methodology: The essential oil was analyzed by Gas Chromatography & Gas Chromatography-Mass Spectrometry in relation with their Kavot indices and mass spectra. Results: The oil was found completely dominated by oxygenated sesquiterpenoids (71.9%) which includes 14-hydroxy-δ-cadinene (37.5%), khusinol (20.7%), viridiflorol (8.0%), acorenone -B (4.2%) and 14-oxy-α-muurolene (1.1%) whereas δ-cadinene (8.9%), α-copaene (6.8%), germacrene-A (2.5%), and β-caryophyllene (1.3%) were the major compounds among sesquiterpenoids. Monoterpenoids constituted as the minor portion (3.8%) of essential oil. The oil was found almost free from oxygenated monoterpenoids (0.2%). The roots of S. vaginatum are used in folk lore medicines in Jammu & Kashmir. The oil from the roots showed marked antifungal activity. The oil had shown 100% mycelia growth inhibition against A. tenuis, C. graminicola, R. solani and S. sclerotiorum at a concentration of 500 µg/ml, 2000 µg/mL, 2000 µg/mL and 300 µg/mL respectively. However F. oxysporum was found less susceptible to the root oil of S. vaginatum. The IC50 values showed a range from 57.4 µg/mL–74.7 µg/mL as compared to standard fungicides with IC50 values 32.8 µg/mL–98.6 µg/mL. The spore germination inhibition test revealed the root oil as a potent inhibitor with IC50 values as 201.4 µg/mL, 414.7 µg/mL and 784.7 µg/mL for A. tenuis, C. graminicola and F. oxysporum. Conclusion: Our study showed that14-hydroxy-δ-cadinene (37.5%), khusinol (20.7%), & viridiflorol (8.0%) are the major components in this oil and possessed potent antifungal activity against test fungal strain, respectively.
ABSTRACT
Integrated pest management is performed at intervals of 10 days, during all the season of rice cultivation, by the application of Trichoderma harzianum at a concentration of 108 spores/ml, in alternation with the mancozeb at 1000 ppm against rice blast and rice leaf spot and the pyrazophos at 750 ppm against blast. The assessment of symptoms is performed at the beginning of the panicles appearance, by estimating the incidence of the disease and the symptoms severity. Thus, at the end of treatment programs, the alternation of pyrazophos and T. harzianum reduced blast at a rate similar to that noted when pyrazophos is used alone (i.e. respectively 90.5 and 89.1%). This percentage is better than that recorded following treatment by T. harzianum alone (78.4%). Mancozeb alternated with T. harzianum reduced blast at a rate of (83.49%) compared with the fungicide or the antagonist alone (77 and 78.4%). The application of mancozeb alone reduced the leaf spot at a rate similar to that noted following its alternation with T. harzianum (79.2 and 75.64%) and better than that obtained after treatment with T. harzianum alone (69.5%).
ABSTRACT
@#<p style="text-align: justify;"><strong>OBJECTIVE:</strong> In view of both the economic importance of ethylenebisdithiocarbamate (EBDC) fungicides in the current agricultural practice and the potential health hazards associated with ethylenethiourea (ETU) exposure, this study aimed to develop and validate a high-pressure liquid chromatography (HPLC) method to determine ETU in biological and environmental samples.</p><p style="text-align: justify;"><strong>METHODS:</strong> The samples were pre-treated according to sample types and were analyzed for ETU using a reversed-phase HPLC system (JASCO?) equipped with UV detector set at 230 nm using C18 bonded silica column and a mobile phase of 0.05M ammonium acetate in methanol (95:5).</p><p style="text-align: justify;"><strong>RESULTS:</strong> The method showed a limit of detection of 0.2 ug/L, with a precision of 3.33 to 12.86 %CV and an accuracy of >90% at 1, 10 and 100 ug/L of ETU in all sample types. The calibration curve was linear from 1 to 200 ug/L for blood, air and water samples and 1 to 2000 ug/L for urine.</p><p style="text-align: justify;"><strong>CONCLUSION:</strong> This method showed an acceptable accuracy, precision, sensitivity and specificity and was used subsequently to determine ETU levels in blood, urine, air, soil and water samples among banana plantation workers.</p>
Subject(s)
EthylenethioureaABSTRACT
Efficacy of resistance induction by the bacterial isolates Pseudomonas putida (TRL2-3), Micrococcus luteus (TRK2-2) and Flexibacteraceae bacterium (MRL412), which were isolated from the rhizosphere of plants growing in Jeju Mountain, were tested in a greenhouse. The disease severity caused by Phytophthora infestans was effectively reduced in the potato plants pre-inoculated with bacterial isolates compared with those of the untreated control plants growing in a greenhouse. In order to estimate the level of protection by the bacterial isolates, Mancozeb WP (Diesen M(R), Kyong nong) and DL-3-amino butyric acid (BABA) were pre-treated, whereas Dimethomorph WP (Forum(R), Kyong nong) and phosphonic acid (H3PO3) were post-treated the challenge inoculation with the pathogen. Disease severities of chemical pre-treated as well as post-treated plants were reduced compare to those of the untreated. The disease reduction in the plants pre-treated with Mancozeb WP was the highest, whereas that of post-treated with Dimethomorph WP was the lowest. The yields of plants pre-inoculated with three bacterial isolates were greatly increased than those of control plants. These results suggest that biological control by bacterial isolates might be an alternative strategy against late blight disease in potato plants growing in greenhouse.