Showing 4 results for Khodakaramian
F. Shahryari, G. Khodakaramian, A. Heydari,
Volume 8, Issue 4 (winter 2005)
Abstract
Representatives of fluorescent pseudomonad strains were assessed for their antagonistic activity against the blackleg of potato pathogen, Pectobacterium carotovorum subsp. atrosepticum. Tested strains belonged mainly to Pseudomonas fluorescens Biovars III, IV and V and they could produce inhibition zone on PDA medium against P. c. subsp. atrosepticum ranging from 1.5-5.5cm. Six selected strains were used in two concentrations 107-109 and 1010-1012 colony forming units to control potato blackleg disease caused by P. c. subsp. atrosepticum under greenhouse conditions. Results showed that all strains applied could reduce the disease ranging from 46 to 71 percent. There was no significant difference among strains and their two concentrations under greenhouse conditions. Most of the strains applied increased potato fresh weight and all of them produced antibiotic and siderophore compounds in vitro.
E. Karimi, H. Rouhani, D. Zafari1, Gh. Khodakaramian, M. Taghinasab,
Volume 11, Issue 41 (fall 2007)
Abstract
In order to study the biological control of carnation vascular wilt disease caused by Fusarium oxysporum f.sp. dianthi, 141 bacterial strains were isolated from carnation rhizosphere, and their antagonistic activity was evaluated against fungal pathogen in dual culture method. Among the tested strains, 16 strains showed antagonistic activity seven of them with more activity were selected for further investigation. Based on phenotypic features, strains E31 and E57 were identified as Bacillus cereus E76, E93, E102 and E121 as Bacillus subtilis and E130 as Pseudomonas fluorescens bv. III. All bacterial strains inhibited mycelial growth of F. o. f. sp. dianthi by production of non-volatile and volatile metabolites under laboratory condition. Microscopical analysis showed that all strains caused deformation of pathogen mycelium, and metabolites of these strains reduced conidia production rate and as well as the ability of conidia germination. In the in vivo tests, in sterilized and nonsterilized soils, the effect of bacterial strains was studied on disease severity, percentage of healthy plants and the growth rate of plants using soil inoculating and root-dipping into bacteria-methyl cellulose mixture methods. The E57 and E121 strains, in both methods, and E130 in root-dipping method showed highest effect on decreasing of disease severity and increasing of healthy plants percentage. Strains E57, E121 and E130 significantly increased total dry weight of carnation. Maximum dry weight was obtained by E57 and E130 in soil inoculating and root –dipping methods respectively.
G. Khodakaramian, J. Swings,
Volume 12, Issue 45 (fall 2008)
Abstract
Protein electrophoretic pattern similarity among 21 strains of Xanthomonas axonopodis pv. citri isolated from Hormozgan and Kerman provinces together with the representatives of reference strains of X.a. pv. citri and X. a. pv. aurantifoli and 246 strains of the other Xanthomonas spp. including : X. a. pv. citri, X. a. pv. glycins, X. a. pv. manihotis, X. c. pv. campestris, X. a. pv. phaseoli, X. cassavae, X. vesicatoria, X. c. pv. euphorbia, X. c. pv. arracaciae, X.c. pv. malvacearum, X. a. pv. clitoriae, X. a. pv. citrumelo, X. a. pv. aurantifolii, X. a. pv. alfalfae, X. cucurbitae, X.c.pv. dieffenbachiae, X. vasicola. pv. holcicola, X. melonis, X. hortorum. pv. pelargonii, X. a. pv. poinsettiicola, X. arboricola pv. pruni, X. c. pv. raphani, X. a. pv. ricini, X. a. pv. vasculorum, X. a. pv. vignicola, X. c. pv. armoraciae, X. c. pv. barbareae and X. c. pv. Carotae was compared and analyzed via Gel Compare version 4.2 software. Results indicated 86% of mean similarity among the strains tested. The highest similarity was 100% for strains isolated from Hormozgan and Kerman provinces and X. a. pv. citri LMG 9176 and X. a. pv. citri LMG 9654. The lowest similarity was 84.90% for these strains and X. c. pv. euphorbia LMG 7402 and X. a. pv. ricini LMG 7444. The 100% of protein pattern similarity among the strains isolated from Hormozgan and Kerman provinces and the reference strains from pathotype A (X. a. pv. citri LMG 9176 and X. a. pv. citri LMG 9654) was supported by host range and pathogenicity patterns of these strains obtained from our previous study.
A. Safadoust , A. Mahboubi, M. R. Mosaddeghi, Gh. Khodakaramian, A. Heydari,
Volume 15, Issue 57 (fall 2011)
Abstract
In this study, the transport of nalidixic acid-resistant Escherichia coli (E. coli NAR) through two soils of sandy loam and clay loam was investigated. Saturated and unsaturated flow conditions were applied at two temperatures of 5 and 20ºC. Leaching was done using large repaired soil columns which had been subjected to physical weathering. A 20-cm diameter disk infiltrometer was set up to establish the steady-state flow conditions. Effluent was sampled at three depths of 15, 30 and 45 cm of soil columns. Saturated flow condition, temperature of 20 ºC and clay loam soil resulted in increasing the bacteria concentration in the leachate. Filtration coefficient and relative adsorption indices in sandy loam soil (average flow conditions, temperature and depth) were greater than those of clay loam soil with the respective values of 33% and 23%. These results may be related to the instability of soil structure and abundance of micropores in the sandy loam columns. In other words, the bacteria were physically blocked and entrapped in the fine pores of sandy loam soil. Effluent bacteria concentration decreased by depth of soil column, indicating the effect of soil on bacterial filtration as a natural filter. Leaching with cold water led to decrement of flow rate and consequently increment of bacterial filtration in the two soils of clay loam and sandy loam (average flow conditions, temperature and depth) with the respective values of 100% and 68%.
