High dilution of Belladonna affect the mycelial growth of Corynespora cassiicola in vitro

Introduction: The target spot is a disease caused by fungus Corynespora cassiicola (Berk. & Curt.) Wei. This disease has occurred in several states of Brazil. It is a late season disease and causes economic losses in various crops such as soybeans [1]. Currently there is no adequate treatment for the control of C. cassiicola in organic cultivation of soybeans, since the application of fungicides for the control and management of diseases is not allowed by Brazilian legislation [2]. Thus, the purpose of this experiment was to test the effectiveness of high dilutions of Belladonna in vitro on mycelial growth of Corynespora cassiicola. Materials and Methods: The preliminary tests were conducted at the Laboratory of Plant Pathology, State University of Maringá (UEM). The fungal isolate of C. cassicola was obtained from Embrapa Soja. The fungus was peaked and grown on PDA (potato dextrose agar) maintained at 25°C ± 2 and 12h photoperiod. Belladonna dilutions (6, 12, 18, 24 and 30dH) were obtained according to the Brazilian Homeopathic Pharmacopoeia [3]. PDA culture medium plus Belladonna dilutions (6, 12, 24 and 30dH) beyond the control containing distilled water were placed in petri dishes after filtration through a Millipore membrane (pore diameter of 0.45µm ). After medium solidification, a disc of mycelium (4 mm diameter) of C. cassiicola was peaked towards the center of each plate and sealed with plastic wrap and then incubated at 25°C with 12h photoperiod. The mycelial growth was measured daily for 8 days. The control consisted of distilled water. The data were analyzed by ANOVA and means were compared by Scott-Knott test (P ≤ 0.05). Results and Discussion: All dilutions of Belladonna (6, 12, 24, 30dH) were effective (p

ELECTRON MICROSCOPIC STUDY OF POPULATIONS OF YEAST-LIKE FUNGI CANDIDA ALBICANS

The article presents the results of electron microscopic investigations of populations of pathogenic Candida albicans № 138 from the museum collection. The morphology of the fungus, its ultrastructure and phases of development in the population were studied. The methods developed at VNIIVSGE for growing bacteria and fungi on the surfaces of Millipore membrane filters without disturbing the architectonics of populations were used in research. The preparations were examined with electron microscope Hitachi 800 (Japan) with two systems: transmission and scanning. At large magnifications, the features of the ultrastructure of Candida albicans cells were studied. It was found that in addition to budding, Candida albicans has a survival strategy in the form of the formation of small blastospore cells, the structure of which is visible only with the use of a scanning electron microscope. The forms, sizes and localization of blastospores with their own development cycle have been studied. The morphology of pseudogyphs, which play an important role in the existence and survival of fungi population, has been studied. The formation of biofilms at a certain stage of development of Candida albicans population was revealed.

Enhanced growth and development of Chrysanthemum morifolium in microponic system under light-emitting diodes

This paper investigated the growth and development of Chrysanthemum shoots in microponic systems in comparison with shoots in micropropagation system. A microponic culture system, combining micropropagation and hydroponics, could reduce the drawbacks of micropropagation system such as reduction of infection, saving of labor, material, space, etc. In this study, Chrysanthemum morifolium shoots with 3 cm in length were cultured in MC (microponic system with circular container - 12 cm diameter at top, 9 cm diameter at bottom and 8.5 cm in height), MR (microponic system with rectangular box - 8.5 cm in height, 35 x 28 cm at top and 30 x 25 cm at bottom) and micropropagation system (MO - rectangular plastic box with 800 ml of half-strength MS medium containing 30 g/l sucrose and 8 mg/l agar). The results indicated that shoots pretreated with 500 ppm IBA, cultured in MC (15 shoots per container) and ventilated with millipore membrane (MillisealTM, pore size 0.5 µm of diameter 2 cm) under 70% red LED combined with 30% blue LED gave thebest plant height, number of roots, fresh weight, and chlorophyll content (a, b and a+b) (5.18 cm, 12.50, 0.52 g, 28.19 µg/g, 13.56 µg/g and 41.75 µg/g, respectively). The survival rates of plants derived from MC and MR in the greenhouse were higher than those in MO (100%, 100% and 85%, respectively). This study indicated that MR was an effective and simple system for large-scale production of Chrysanthemum morifolium.

Ocimum americanum L. Essential Oil Exhibits Antimicrobial Activity Against Oral Bacteria Related to Periodontal Disease

The aim of this study was to evaluate the antimicrobial property of essential oil extracted from the leaves ofOcimum americanumagainst oral bacteria related to periodontal disease. Three species of periodontal pathogens includingPorphyromonas gingivalisW50,Prevotella intermediaATCC 25611 andFusobacterium nucleatumATCC 25586 were included in the study. Agar diffusion was performed initially to screen the antimicrobial activity ofO.americanumessential oil. Minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) were then determined using the Millipore Membrane method. The result showed that in the agar diffusion, essential oil extracted fromOcimum americanumexhibited antimicrobial activity against all test bacteria with the zone of inhibition ranging from 24 to 30 mm. The MIC values againstP. gingivalisandP. intermediawere 0.35 mg/mL whereas that ofF. nucleatumwas 0.70 mg/mL. The MBC values againstP. gingivalisandP. intermediawere 0.70 mg/mL whereas that ofF. nucleatumwas 1.4 mg/mL. In conclusion,O.americanumessential oil has an antimicrobial activity which may be a beneficial component of oral health care products to control or prevent periodontal disease by reducing these bacteria in the oral cavity.

New method for screening rice varieties against Bakanae disease

Several varietal screening methods were tested along with dipping dry seeds into millipore membrane filtrate of spore suspension of the pathogen and gibberellic acid (GA3) in different concentrations. It was found that GA3 can be used to screen out susceptible rice varieties against bakanae disease. The method which requires the use of GA3 is easier than the other methods for mass screening as it does not require maintaining living culture of the pathogen. The protocol of inoculum free varietal screening method for bakanae disease of rice was developed to find out resistant varieties from the huge collections of germplasm bank. DOI: http://dx.doi.org/10.3329/bjb.v42i2.18036 Bangladesh J. Bot. 42(2): 315-320, 2013 (December)

The Catalytic Influence of Sulfolobus metallicus in the Bioleaching of Chalcopyrite: Role of Attached and Planktonic Population

The catalytic influence of Sulfolobus metallicus in the bioleaching of pure chalcopyrite at 70° C and pH 1.5 was studied in shake flask experiments. In order to evaluate separately the influence of planktonic and attached cells on the catalytic process, in some experiments the microorganisms were prevented from reaching chalcopyrite surface by keeping them in a chamber separated by a 0.1 Millipore membrane. Leaching, which was conducted with a -80 # + 120# chalcopyrite sample, was characterized from monitoring Eh, pH, copper, ferrous and ferric ion concentration in solution. In addition, the concentration of different sulphur species dissolved in solution either in aerated-abiotic and aerobic - biotic conditions, was determined with HPLC. Maximum copper dissolution was reached in experiments where all the microorganisms could reach chalcopyrite. In experiments where microorganisms were maintained separated from the sulphide, the population of microorganisms still increased. However, in this case copper dissolution was only 50 % of the maximum reached when contact of microorganisms with chalcopyrite was allowed, similar to that obtained in aerobic-abiotic conditions. On the other hand, in aerobic-abiotic conditions there was formation of bisulfite (HSO3)-, bisulfate (HSO4)- and sulfate (SO4)2-, while in leaching experiments where microorganisms could reach chalcopyrite the formation of thiosulfate (S2O3)2- and sulfite (SO3)2- was additionally observed. It can be concluded that bioleaching of chalcopyrite in the presence of Sulfolobus metallicus is the result of the cooperative action of attached cells which catalize copper dissolution through formation of thiosulfate, sulfite and bisulfite, and planktonic cells which further oxidize these intermediate compound to bi-sulfate and sulfate.