Field Evaluation of Native Fungus, Beauveria bassiana (Bals.) Vuillemin Against some Piercing-Sucking Insects on the Grapevine

2021 ◽  
Vol 24 (1) ◽  
pp. 158-164
Author(s):  
Samy Sayed ◽  
Saad Al-Otaibi ◽  
Ahmed El-Shehawi ◽  
Sayed-Ashraf Elarnaouty ◽  
Samir El-Shazly ◽  
...  
2016 ◽  
Vol 58 (4) ◽  
pp. 214-219 ◽  
Author(s):  
Iwona Skrzecz ◽  
Elżbieta Popowska-Nowak ◽  
Robert Wolski ◽  
Alicja Sowińska ◽  
Tomasz Jabłoński ◽  
...  

Abstract Small banded pine weevil Pissodes castaneus is one of the most dangerous pests of Pinus sylvestris plantations and thickets. The lack of effective and environmentally safe methods of limiting the number of the pest justified to undertake the studies aimed at the laboratory and field evaluation of biological activity of entomopathogenic fungus Beauveria bassiana used to reduce the numbers of small banded pine weevil. In laboratory, the beetles were reared on the sections of fresh Scots pine twigs that were treated with five suspensions containing from 1 × 104 to 1 × 108 conidia of B. bassiana in 1 ml. During the 3-week rearing, insect mortality was determined and median lethal concentration LC50 was calculated. The field treatments consisted of spraying 4-year-old P. sylvestris trees with two formulations of fungus containing 1 × 108 conidia ml−1 of suspension. Treatments consisted of spraying 4-year-old P. sylvestris trees with two fungus formulations containing 1 × 108 conidia ml−1. High insecticidal activity of B. bassiana was found because the pathogen caused the death of 14-94% of P. castaneus beetles, LC50 = 6.51 × 105 conidia ml−1. Field treatments did not result in the reduction of plant damage caused by small banded pine weevil; therefore, the spraying of trees with B. bassiana cannot be recommended to protect the young stands of P. sylvestris against pest.


2019 ◽  
Vol 29 (1) ◽  
Author(s):  
Monir M. M. El Husseini

AbstractLarval and adult populations of the Egyptian alfalfa weevil (EAW) Hypera brunneipennis (Boheman) (Coleoptera: Curculionidae) was monitored after application of the entomopathogenic fungus Beauveria bassiana in the alfalfa field (Medicago sativa L.) in two successive seasons 2014/2015 and 2015/2016. The second and last generation of the weevil on April 10, 2016, was controlled by only one application with the conidiospores of the entomopathogenic fungus B. bassiana (3 × 108 spores/ml). Accordingly, the larval population decreased from 16.07 ± 1.09 in season 2015/2016 to 7.37 ± 0.05 individuals/50 sweep net double strokes in season 2016/2017. Also, the adult weevil’s population decreased from 5.66 ± 0.8 to 2.55 ± 0.6 individuals/50 sweep net double strokes in the two seasons, respectively. 39.66% mortality rate was recorded in the Hypera brunneipennis adults aestivated under loose bark of the surrounding eucalyptus trees, which received the application of B. bassiana in the field. Another application with the fungus, targeting the second generation of the pest adults in alfalfa each season, will undoubtedly lead to a further decrease in the pest population.


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Laila Gasmi ◽  
Sehyeon Baek ◽  
Jong Cheol Kim ◽  
Sihyeon Kim ◽  
Mi Rong Lee ◽  
...  

AbstractBeauveria bassiana is a species complex whose isolates show considerable natural genetic variability. However, little is known about how this genetic diversity affects the fungus performance. Herein, we characterized the diversity of genes involved in various mechanisms of the infective cycle of 42 isolates that have different growth rates, thermotolerance and virulence. The analysed genes showed general genetic diversity measured as non-synonymous changes (NSC) and copy number variation (CNV), with most of them being subjected to positive episodic diversifying selection. Correlation analyses between NSC or CNV and the isolate virulence, thermotolerance and growth rate revealed that various genes shaped the biological features of the fungus. Lectin-like, mucin signalling, Biotrophy associated and chitinase genes NSCs correlated with the three biological features of B. bassiana. In addition, other genes (i.e. DNA photolyase and cyclophilin B) that had relatively conserved sequences, had variable CNs across the isolates which were correlated with the variability of either virulence or thermotolerance of B. bassiana isolates. The data obtained is important for a better understanding of population structure, ecological and potential impact when isolates are used as mycoinsecticides and can justify industrialization of new isolates.


Viruses ◽  
2018 ◽  
Vol 10 (12) ◽  
pp. 665 ◽  
Author(s):  
Charalampos Filippou ◽  
Inmaculada Garrido-Jurado ◽  
Nicolai Meyling ◽  
Enrique Quesada-Moraga ◽  
Robert Coutts ◽  
...  

The use of mycoviruses to manipulate the virulence of entomopathogenic fungi employed as biocontrol agents may lead to the development of novel methods to control attacks by insect pests. Such approaches are urgently required, as existing agrochemicals are being withdrawn from the market due to environmental and health concerns. The aim of this work is to investigate the presence and diversity of mycoviruses in large panels of entomopathogenic fungi, mostly from Spain and Denmark. In total, 151 isolates belonging to the genera Beauveria, Metarhizium, Lecanicillium, Purpureocillium, Isaria, and Paecilomyces were screened for the presence of dsRNA elements and 12 Spanish B. bassiana isolates were found to harbor mycoviruses. All identified mycoviruses belong to three previously characterised species, the officially recognised Beauveria bassiana victorivirus 1 (BbVV-1) and the proposed Beauveria bassiana partitivirus 2 (BbPV-2) and Beauveria bassiana polymycovirus 1 (BbPmV-1); individual B. bassiana isolates may harbor up to three of these mycoviruses. Notably, these mycovirus species are under distinct selection pressures, while recombination of viral genomes increases population diversity. Phylogenetic analysis of the RNA-dependent RNA polymerase gene sequences revealed that the current population structure in Spain is potentially a result of both vertical and horizontal mycovirus transmission. Finally, pathogenicity experiments using the Mediterranean fruit fly Ceratitis capitata showed no direct correlation between the presence of any particular mycovirus and the virulence of the B. bassiana isolates, but illustrated potentially interesting isolates that exhibit relatively high virulence, which will be used in more detailed virulence experimentation in the future.


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