Essential oil of Chrysanthemum indicum L.: potential biocontrol agent against plant pathogen Phytophthora nicotianae

Phytophthora nicotianae causes black shank, a serious soil-borne disease, in tobacco. In this study, the Bacillus strain GUMT319 was isolated from the rhizosphere of healthy tobacco plants grown in a field in Guizhou with a high incidence of tobacco black shank. Genome sequencing revealed that GUMT319 contained a single circular chromosome 3,940,023 bp in length, with 4,053 predicted genes and an average GC content of 46.6%. Based on phylogenomic analyses, GUMT319 was designated as Bacillus velezensis. The genome of GUMT319 contained more than 60 genes and 13 gene clusters that have previously been found to be active in antifungal mechanisms, biofilm formation, and chemotaxis motility. Additionally, confocal laser scanning microscopy and scanning electron microscopy showed that GUMT319 formed a spatially organized biofilm in vivo. In addition, lauric acid negatively regulated biofilm formation. This is the first study to report that nicotine in tobacco root exudates was a chemoattractant for biocontrol Bacillus strains. In this study, we identified new interactions between beneficial microorganisms and tobacco roots in the rhizosphere. Moreover, dual culture tests in vitro showed that GUMT319 inhibited the growth of P. nicotianae and also displayed inhibitory effects against eight other plant pathogens, namely, Colletotrichum scovillei, Colletotrichum capsici, Fusarium carminascens, Sclerotinia sclerotiorum, Alternaria alternata, Phomopsis sp., Phyllosticta sorghina, and Exserohilum turcicum. Furthermore, GUMT319 exhibited > 70% control efficiency against tobacco black shank in field experiments conducted in 2018–2020. Thus, GUMT319 was more effective in controlling the incidence of tobacco black shank than other treatments including fungicide application. Overall, these results suggested that GUMT319 (B. velezensis) could be used as a potential biocontrol agent against tobacco black shank.

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What habitat does spiny snout mite occupy in Tasmania

New Zealand Plant Protection ◽

10.30843/nzpp.2015.68.5854 ◽

2015 ◽

Vol 68 ◽

pp. 446-446

Author(s):

D.J. Wilson ◽

P.J. Gerard

Keyword(s):

New Zealand ◽

Sand Dune ◽

Biocontrol Agent ◽

Predatory Mites ◽

Mite Species ◽

Predatory Mite ◽

Habitat Specificity ◽

Nontarget Organisms ◽

Flea Control ◽

Potential Biocontrol Agent

Spiny snout mite (Neomolgus capillatus) is a potential biocontrol agent for clover flea (Sminthurus viridis) a white clover pest on dairy farms in warmer and wetter parts of New Zealand In the 1990s this mite was introduced from Brittany France into Tasmania for clover flea control Results during the release programme were highly promising and subsequent anecdotal farmer reports indicate widespread decreases in damage As N capillatus is a predatory mite and already known to attack nontarget organisms habitat specificity will determine whether it could be introduced into New Zealand without risk to native insects To assess this pastures on nine of the original Tasmanian release farms and adjacent nontarget habitats ranging from bush wetlands eucalypt stands to sand dune country were sampled in April 2014 Litter samples were collected heat extracted and mite species identified Neomolgus capillatus was found at effective densities in pastures that had good clover cover Where present it displaced Bdellodes spp mites that are ineffective against clover flea No N capillatus were found in the nontarget habitats all of which lacked clover and contained other predatory mites including Bdellodes spp Therefore the preference by N capillatus for lush pastures makes it an excellent prospect for introduction as a biocontrol agent into clover flea prone regions of New Zealand

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GroEL protein from the potential biocontrol agent Rhodopseudomonas palustris enhances resistance to rice blast disease

Pest Management Science ◽

10.1002/ps.6584 ◽

2021 ◽

Author(s):

Xiyang Wu ◽

Yue Chen ◽

Chenggang Li ◽

Xin Zhang ◽

Xinqiu Tan ◽

...

Keyword(s):

Rice Blast ◽

Biocontrol Agent ◽

Rhodopseudomonas Palustris ◽

Rice Blast Disease ◽

Blast Disease ◽

Groel Protein ◽

Potential Biocontrol Agent

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A Preliminary Assessment of Amblyseius andersoni (Chant) as a Potential Biocontrol Agent against Phytophagous Mites Occurring on Coniferous Plants

Insects ◽

10.3390/insects12080664 ◽

2021 ◽

Vol 12 (8) ◽

pp. 664

Author(s):

Ewa Puchalska ◽

Stanisław Kamil Zagrodzki ◽

Marcin Kozak ◽

Brian G. Rector ◽

Anna Mauer

Keyword(s):

Biocontrol Agent ◽

Mass Rearing ◽

Predator Population ◽

Preliminary Assessment ◽

Amblyseius Andersoni ◽

Food Items ◽

Oligonychus Ununguis ◽

Potential Biocontrol Agent ◽

Pine Pollen ◽

Survival And Reproduction

Development, survival and reproduction of Ambyseius andersoni (Chant), a predatory mite widely distributed in Europe, were assessed on different food items. These included two key pests of ornamental coniferous plants, i.e., Oligonychus ununguis (Jacobi) and Pentamerismus taxi (Haller) and pollen of Pinus sylvestris L. The rationale behind these experiments was to provide a preliminary assessment of the potential of A. andersoni as a biocontrol agent of the above phytophagous arthropods and evaluate pine pollen as an alternative food source for the predator. Under laboratory conditions (23 ± 0.5 °C, 70 ± 10% RH and 16L:8D) A. andersoni was able to feed, develop and reproduce on all tested diets. The shortest development time (egg to female) was obtained when the predator fed on P. taxi (mean = 5.12 d) and the longest was on pine pollen (mean = 6.55 d). The rm value was significantly higher on both tested prey (0.166 on P. taxi and 0.160 on O. ununguis) than on pollen (0.139). Thus, we do not recommend pine pollen for mass rearing of A. andersoni; however, we conclude that pollen may provide sufficient sustenance for the predator population under field conditions when prey are absent. The potential of A. andersoni as a biocontrol agent of O. ununguis and P. taxi is discussed.

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Host Range of the Argentine Root Borer Carmenta haematica (Ureta) (Lepidoptera: Sesiidae), a Potential Biocontrol Agent for Snakeweeds (Gutierrezia spp) in the United States

Biological Control ◽

10.1006/bcon.1995.1001 ◽

1995 ◽

Vol 5 (1) ◽

pp. 1-10 ◽

Cited By ~ 8

Author(s):

H.A. Cordo ◽

C.J. Deloach ◽

R. Ferrer

Keyword(s):

United States ◽

Host Range ◽

Biocontrol Agent ◽

The United States ◽

Potential Biocontrol Agent

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The influence of the essential oil extracted from hops on monolayers and bilayers imitating plant pathogen bacteria membranes

Colloids and Surfaces B Biointerfaces ◽

10.1016/j.colsurfb.2018.10.047 ◽

2019 ◽

Vol 173 ◽

pp. 672-680 ◽

Cited By ~ 3

Author(s):

Karolina Połeć ◽

Beata Barnaś ◽

Magdalena Kowalska ◽

Michał Dymek ◽

Rafał Rachwalik ◽

...

Keyword(s):

Essential Oil ◽

Plant Pathogen

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Biology and host specificity of Gonatocerus deleoni (Hymenoptera: Mymaridae), a potential biocontrol agent of Homalodisca vitripennis (Hemiptera: Cicadellidae) in California, USA

BioControl ◽

10.1007/s10526-011-9391-5 ◽

2011 ◽

Vol 57 (1) ◽

pp. 61-69 ◽

Cited By ~ 4

Author(s):

John Lytle ◽

J. G. Morse ◽

S. V. Triapitsyn

Keyword(s):

Host Specificity ◽

Biocontrol Agent ◽

Homalodisca Vitripennis ◽

Potential Biocontrol Agent

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Oxidative Stress Correlates with Wolbachia-Mediated Antiviral Protection in Wolbachia-Drosophila Associations

Applied and Environmental Microbiology ◽

10.1128/aem.03847-14 ◽

2015 ◽

Vol 81 (9) ◽

pp. 3001-3005 ◽

Cited By ~ 42

Author(s):

Zhee Sheen Wong ◽

Jeremy C. Brownlie ◽

Karyn N. Johnson

Keyword(s):

Oxidative Stress ◽

Hydrogen Peroxide ◽

Biocontrol Agent ◽

Oxygen Species ◽

Content Type ◽

Host Insect ◽

Fitness Traits ◽

Endogenous Reactive Oxygen Species ◽

Potential Biocontrol Agent ◽

Definition Of

ABSTRACTWolbachiamediates antiviral protection in insect hosts and is being developed as a potential biocontrol agent to reduce the spread of insect-vectored viruses. Definition of the molecular mechanism that generates protection is important for understanding the tripartite interaction between host insect,Wolbachia, and virus. Elevated oxidative stress was previously reported for a mosquito line experimentally infected withWolbachia, suggesting that oxidative stress is important forWolbachia-mediated antiviral protection. However,Wolbachiaexperimentally introduced into mosquitoes impacts a range of host fitness traits, some of which are unrelated to antiviral protection. To explore whether elevated oxidative stress is associated with antiviral protection inWolbachia-infected insects, we analyzed oxidative stress of fiveWolbachia-infectedDrosophilalines. In flies infected with protectiveWolbachiastrains, hydrogen peroxide concentrations were 1.25- to 2-fold higher than those in paired fly lines cured ofWolbachiainfection. In contrast, there was no difference in the hydrogen peroxide concentrations in flies infected with nonprotectiveWolbachiastrains compared to flies cured ofWolbachiainfection. Using aDrosophilamutant that produces increased levels of hydrogen peroxide, we investigated whether flies with high levels of endogenous reactive oxygen species had altered responses to virus infection and found that flies with high levels of endogenous hydrogen peroxide were less susceptible to virus-induced mortality. Taken together, these results suggest that elevated oxidative stress correlates withWolbachia-mediated antiviral protection in naturalDrosophilahosts.

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