scholarly journals The effect of chitin on the biological activity of Bacillus subtilis strains

2020 ◽  
Vol 103 (4) ◽  
pp. 233-240
Author(s):  
I. L. Krasnobaeva ◽  
N. M. Kovalenko* ◽  
E. V. Popova
Keyword(s):  
Bacillus Subtilis ◽  
Colloidal Suspension ◽  
Alternaria Solani ◽  
Antagonistic Activity ◽  
Brown Spot ◽  
Colloidal Chitin ◽  
Submerged Cultivation ◽  
Laboratory Sample ◽  
Dark Brown Spot ◽  
Chitin And Chitosan

The aim of the work was to assess the effect of various forms of chitin and chitosan during submerged cultivation of Bacillus subtilis strains, which form the basis of the laboratory sample Vitaplan, CL, on the synthesis of chitinase, as well as on the antagonistic activity and inducing effect of B. subtilis strains in the pathosystems of wheat - Cochliobolus sativus and Puccinia recondita f. sp. tritici. The inclusion of chitin in the form of dry powder or chitin and chitosan in the form of a colloidal suspension into the medium for deep cultivation of bacteria showed that only colloidal chitin increased the antagonistic activity of B. subtilis strains against test cultures of Alternaria solani and Clavibacter michiganensis. The ability of B. subtilis strains to synthesize extracellular chitinase when cultivated in a medium containing colloidal chitin was established. A higher fungistatic effect of the laboratory sample Vitaplan CL + colloidal chitin against Cohliobolus sativus was revealed as compared to the original sample. It was shown that the laboratory sample Vitaplan, CL + colloidal chitin increases the resistance of wheat to dark brown spot and brown rust 1.5–2.0 times more effectively as compared to Vitaplan, CL. As a result of the research, a laboratory sample of Vitaplan, CL + colloidal chitin was obtained with increased antagonistic and inducing activity as compared to Vitaplan, CL.

Antagonistic activity of Bacillus subtilis strains isolated from various sources

2018 ◽  
Vol 8 (2) ◽  
pp. 354-364
Author(s):  
A. N. Irkitova ◽  
A. V. Grebenshchikova ◽  
A. V. Matsyura
Keyword(s):  
Escherichia Coli ◽  
Bacillus Subtilis ◽  
Wild Strain ◽  
Fish Farming ◽  
Antagonistic Activity ◽  
Antagonistic Effect ◽  
E Coli ◽  
Long Period ◽  
Test Culture ◽  
Agar Media

<p>An important link in solving the problem of healthy food is the intensification of the livestock, poultry and fish farming, which is possible only in the adoption and rigorous implementation of the concept of rational feeding of animals. In the implementation of this concept required is the application of probiotic preparations. Currently, there is an increased interest in spore probiotics. In many ways, this can be explained by the fact that they use no vegetative forms of the bacilli and their spores. This property provides spore probiotics a number of advantages: they are not whimsical, easily could be selected, cultivated, and dried. Moreover, they are resistant to various factors and could remain viable during a long period. One of the most famous spore microorganisms, which are widely used in agriculture, is <em>Bacillus subtilis</em>. Among the requirements imposed to probiotic microorganisms is mandatory – antagonistic activity to pathogenic and conditional-pathogenic microflora. The article presents the results of the analysis of antagonistic activity of collection strains of <em>B. subtilis</em>, and strains isolated from commercial preparations. We studied the antagonistic activity on agar and liquid nutrient medias to trigger different antagonism mechanisms of <em>B. subtilis</em>. On agar media, we applied three diffusion methods: perpendicular bands, agar blocks, agar wells. We also applied the method of co-incubating the test culture (<em>Escherichia coli</em>) and the antagonist (or its supernatant) in the nutrient broth. Our results demonstrated that all our explored strains of <em>B. subtilis</em> have antimicrobial activity against a wild strain of <em>E. coli</em>, but to varying degrees. We identified strains of <em>B. subtilis</em> with the highest antagonistic effect that can be recommended for inclusion in microbial preparations for agriculture.</p><p><em><br /></em><em></em></p>

scholarly journals Pentatomids associated with blackberry

2014 ◽  
Vol 38 (3) ◽  
pp. 256-261
Author(s):  
Mauricio Paulo Batistella Pasini ◽  
Alessandro Dal'Col Lúcio
Keyword(s):  
Rio Grande ◽  
Nezara Viridula ◽  
Brown Spot ◽  
Stink Bug ◽  
Stink Bugs ◽  
Rio Grande Do Sul ◽  
Dark Brown Spot ◽  
Euschistus Heros ◽  
Santa Maria ◽  
Piezodorus Guildinii

Information concerning the presence of stink bugs in blackberry (Rubus spp.) in Brazil is sparse. This study aimed to identify the stink bug species associated with blackberry, to establish the daily dynamics and evaluate the fruits damage. The experiment was conducted in Santa Maria, Rio Grande do Sul State, Brazil, in blackberry orchard. Presence and evaluations of stink bugs were done weekly through visual and sweeping samplings at different day times. Five species of pentatomids were identified: Piezodorus guildinii, Nezara viridula, Euschistus heros, Dichelops furcatus and Edessa meditabunda. The bugs attack the drupelets producing a dark brown spot and wrinkled berries.

scholarly journals A new species of Amazonian snouted treefrog (Hylidae:Scinax) with description of a novel species-habitat association for an aquatic breeding frog

PeerJ ◽  
2018 ◽  
Vol 6 ◽  
pp. e4321 ◽  
Author(s):  
Miquéias Ferrão ◽  
Rafael de Fraga ◽  
Jiří Moravec ◽  
Igor L. Kaefer ◽  
Albertina P. Lima
Keyword(s):  
New Species ◽  
Species Abundance ◽  
Dominant Frequency ◽  
Lateral View ◽  
Habitat Associations ◽  
Brown Spot ◽  
Advertisement Call ◽  
Habitat Association ◽  
Dark Brown Spot ◽  
A New Species

The genusScinaxis one of the most specious genera of treefrogs of the family Hylidae. Despite the high number of potential new species ofScinaxrevealed in recent studies, the rate of species descriptions for Amazonia has been low in the last decade. A potential cause of this low rate may be the existence of morphologically cryptic species. Describing new species may not only impact the taxonomy and systematics of a group of organisms but also benefit other fields of biology. Ecological studies conducted in megadiverse regions, such as Amazonia, often meet challenging questions concerning insufficient knowledge of organismal alpha taxonomy. Due to that, detecting species-habitat associations is dependent on our ability to properly identify species. In this study, we first provide a description of a new species (including its tadpoles) of the genusScinaxdistributed along heterogeneous landscapes in southern Amazonia; and secondly assess the influence of environmental heterogeneity on the new species’ abundance and distribution.Scinax ruberoculatussp. nov. differs from all nominal congeners by its small size (SVL 22.6–25.9 mm in males and 25.4–27.5 mm in females), by having a dark brown spot on the head and scapular region shaped mainly like the mothCopiopteryx semiramis(or a human molar in lateral view, or a triangle), bicolored reddish and grey iris, snout truncate in dorsal view, bilobate vocal sac in males, by its advertisement call consisting of a single pulsed note with duration of 0.134–0.331 s, 10–23 pulses per note, and dominant frequency 1,809–1,895 Hz. Both occurrence and abundance of the new species are significantly influenced by silt content in the soil. This finding brings the first evidence that edaphic factors influence species-habitat association in Amazonian aquatic breeding frogs.

scholarly journals Identification of the Fungal Pathogens of Postharvest Disease on Peach Fruits and the Control Mechanisms of Bacillus subtilis JK-14

Toxins ◽  
2019 ◽  
Vol 11 (6) ◽  
pp. 322 ◽  
Author(s):  
Shuwu Zhang ◽  
Qi Zheng ◽  
Bingliang Xu ◽  
Jia Liu
Keyword(s):  
Biological Control ◽  
Bacillus Subtilis ◽  
Fungal Pathogens ◽  
Biological Control Agent ◽  
Storage Period ◽  
Control Agent ◽  
Antagonistic Activity ◽  
Postharvest Disease ◽  
Economic Losses ◽  
Control Mechanisms

Postharvest fungal disease is one of the significant factors that limits the storage period and marketing life of peaches, and even result in serious economic losses worldwide. Biological control using microbial antagonists has been explored as an alternative approach for the management of postharvest disease of fruits. However, there is little information available regarding to the identification the fungal pathogen species that cause the postharvest peach diseases and the potential and mechanisms of using the Bacillus subtilis JK-14 to control postharvest peach diseases. In the present study, a total of six fungal isolates were isolated from peach fruits, and the isolates of Alternaria tenuis and Botrytis cinerea exhibited the highest pathogenicity and virulence on the host of mature peaches. In the culture plates, the strain of B. subtilis JK-14 showed the significant antagonistic activity against the growth of A. tenuis and B. cinerea with the inhibitory rates of 81.32% and 83.45% at 5 days after incubation, respectively. Peach fruits treated with different formulations of B. subtilis JK-14 significantly reduced the mean disease incidences and lesion diameters of A. tenuis and B. cinerea. The greatest mean percent reduction of the disease incidences (81.99% and 71.34%) and lesion diameters (82.80% and 73.57%) of A. tenuis and B. cinerea were obtained at the concentration of 1 × 107 CFU mL−1 (colony forming unit, CFU). Treatment with the strain of B. subtilis JK-14 effectively enhanced the activity of the antioxidant enzymes-superoxide dismutase (SOD), peroxidase (POD) and catalase (CAT) in A. tenuis and B. cinerea inoculated peach fruits. As such, the average activities of SOD, POD and CAT were increased by 36.56%, 17.63% and 20.35%, respectively, compared to the sterile water treatment. Our results indicate that the isolates of A. tenuis and B. cinerea are the main pathogens that cause the postharvest peach diseases, and the strain of B. subtilis JK-14 can be considered as an environmentally-safe biological control agent for the management of postharvest fruits diseases. We propose the possible mechanisms of the strain of B. subtilis JK-14 in controlling of postharvest peach diseases.

scholarly journals THE LIFE HISTORY OF EPIRRANTHIS OBFIRMARIA, Hbn.

1897 ◽  
Vol 29 (11) ◽  
pp. 258-259
Author(s):  
Thomas W. Fyles
Keyword(s):  
Life History ◽  
Brown Spot ◽  
Dark Brown Spot ◽  
History Of

Epirranthis obfirmaria is a swamp insect. I take it in “The Gomin” near Quebec, where, in ordinary seasons, it is on the wing from early in June till the close of that month. The following is a brief description of this beautiful insect:♂. Expanse of wings one inch; length of body half an inch; length of antennæ three-tenths of an inch. Colour a rich, warm brown. The primaries have a broad ochreous band, widest at the costa, outlined with dark brown. In this band, not far from the costa, is a dark brown spot. The secondaries have the outer third of the same warm brown as the primaries, with an ochreous patch at the outer angle of it. The rest of the wing is ochreous, clouded towards the base. The marginal dark brown line of this ochreous portion is somewhat angulated. In the part of lighest colour in the wing is a conspicuous dark brown spot. The antennæ are pectinsted.

Study on the production of chitin and chitosan from shrimp shell by using Bacillus subtilis fermentation

2007 ◽  
Vol 342 (16) ◽  
pp. 2423-2429 ◽  
Author(s):  
Theruvathil K. Sini ◽  
Sethumadhavan Santhosh ◽  
Paruthapara T. Mathew
Keyword(s):  
Bacillus Subtilis ◽  
Shrimp Shell ◽  
Chitin And Chitosan

Characterization of an antifungal soil bacterium and its antagonistic activities againstFusariumspecies

2003 ◽  
Vol 49 (4) ◽  
pp. 253-262 ◽  
Author(s):  
Yiu-Kwok Chan ◽  
Wayne A McCormick ◽  
Keith A Seifert
Keyword(s):  
Bacillus Subtilis ◽  
Culture Filtrate ◽  
Fusarium Species ◽  
Hyphal Growth ◽  
Antagonistic Activity ◽  
Plant Diseases ◽  
Ear Rot ◽  
In Planta ◽  
Head Blight

Bacteria were isolated from a cultivated soil and screened for antagonistic activity against Fusarium graminearum, a predominant agent of ear rot and head blight in cereal crops. Based on its in vitro effectiveness, isolate D1/2 was selected for characterization and identified as a strain of Bacillus subtilis by phenotypic tests and comparative analysis of its 16S ribosomal RNA gene (rDNA) sequence. It inhibited the mycelial growth of a collection of common fungal phytopathogens, including eight Fusarium species, three other ascomycetes, and one basidiomycete. The cell-free culture filtrate of D1/2 at different dilutions was active against macroconidium germination and hyphal growth of F. graminearum, depending on the initial macroconidium density. It induced the formation of swollen hyphal cells in liquid cultures of this fungus grown from macroconidia. A bioassay also demonstrated that D1/2 offered in planta protection against the damping-off disease in alfalfa seedlings caused by F. graminearum, while the type strain of B. subtilis was ineffective. Hence, B. subtilis D1/2 or its culture filtrate has potential application in controlling plant diseases caused by Fusarium.Key words: antifungal activity, Bacillus subtilis, biological control, biopesticide, Fusarium species.

scholarly journals NOTES ON LEPIDOPTERA

1880 ◽  
Vol 12 (11) ◽  
pp. 228-231
Author(s):  
H. S. Jewett
Keyword(s):  
The Body ◽  
Brown Spot ◽  
Dark Brown Spot ◽  
Pale Green

Euchaetes collaris. Fitch.On Jnne 7th, 1879, I obtained some eggs from a ♀ captured the day before. The eggs were smooth, pale green, spherical in shape and inch in diameter. The eggs hatched on the 12th. Larva ⅛ inch long, pale green, largest at middle of the body and tapering slightly towards both ends. Head slightly bilobed, of a faint brownish color, with a dark brown spot on each side.

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