Biological control of pathogenic and secondary (non pathogenic) fungi associated with Barley (Hordeum vulgare) seeds

2017 ◽  
Vol 2 (2) ◽  
pp. 10-14 ◽  
Author(s):  
Ihsan Flayyih Hasan AI-Jawhari ◽  
2014 ◽  
Vol 14 (2) ◽  
Author(s):  
R. Soelistijono

This study examines the effectiveness of mycorrhizal Rhizoctonia resistance induction in Phalaenopsis amabilis against Fusarium sp. Fusarium solani is known as pathogens that attack many orchids P. amabilis (Chung et al., 2011) compared to other pathogenic fungi. Attack of Fusarium sp. will cause rot and yellow colored leaves. Until now there has been known as a biological control orchid against Fusarium sp. In this study tested the endurance locations in Sleman and Surakarta to see the effectiveness of a good orchid growth induced by Rhizoctonia mycorrhizal or not to attack by Fusarium sp. The results of the study showed that mycorrhizal Rhizoctonia able to inhibit the attack of Fusarium sp. It is shown by the value of the index of disease resistance  (DSI) in P. amabilis orchid mycorrhizal Rhizoctonia induced lower than that not induced. Mycorrhizal Rhizoctonia induction results in Sleman provide a more real than mycorrhizal Rhizoctonia induction in Surakarta.


2016 ◽  
Vol 44 (1) ◽  
pp. 60-66
Author(s):  
Xuehua ZHANG ◽  
Linling LI ◽  
Shuiyuan CHENG ◽  
Hua CHENG

Fungal diseases of plants continue to contribute to heavy crop losses in spite of the best control efforts of plant pathologists. Breeding for disease-resistant varieties and the application of synthetic chemical fungicides are the most widely accepted approaches in plant disease management. CMN1308 strain of Bacillus amyloliquefaciens was isolated from healthy Chinese chestnut fruit, which has antibiosis and induced resistance to the prevention mechanism of pathogenic bacterium after picking. In order to evaluate the antibiosis mechanism, CMN1308 was fostered with the method of confront culture. The antimicrobial components were also isolated from the culture of CMN1308, and their stability and antimicrobial activity was tested under different treatments such as temperature, pH and UV. The results showed that CMN1308 displays advantages in regard to spatial competition against the major pathogens of chestnut, Rhizopus stolonifer, Fusarium solani, Stachybotrys chartarum, Cryphonectria parasitica, Lasiodiplodia theobromae, Penicillium expansum and Aspergillus niger. Among this, CMN1308 had the best antimicrobial activity against P. expansum, with the inhibition zone diameter of 27.1 mm. The antimicrobial material isolated from CMN1308 culture showed a strong inhibition to the growth of P. expansum hyphal and also had a good stability to high temperature, alkali media and UV, but was sensitive to acidic conditions. Furthermore, CMN1308 increased the peroxidase, polyphenol oxidase activity and reduced the MDA content in chestnuts after infecting by pathogenic fungi. Thus, producing antibiotic compounds and inducible resistance are the main factors that may explain the antibacterial mechanism of CMN1308 on chestnut pathogenic. The results of this study might help to optimize the practical use of CMN1308 in the biological control of chestnut rot or other fruit rot infected by pathogenic fungi.


2018 ◽  
Vol 121 ◽  
pp. 216-222 ◽  
Author(s):  
Noé Medina-Córdova ◽  
Sergio Rosales-Mendoza ◽  
Luis Guillermo Hernández-Montiel ◽  
Carlos Angulo

2021 ◽  
Vol 45 ◽  
Author(s):  
Tarcísio Marcos Macedo Mota Filho ◽  
Luis Eduardo Pontes Stefanelli ◽  
Roberto da Silva Camargo ◽  
Carlos Alberto Oliveira de Matos ◽  
Luiz Carlos Forti

ABSTRACT Chemical control using toxic baits containing the active ingredient sulfluramid at 0.3% (w/w) is the main method for controlling leaf-cutting ants of the genera Atta and Acromyrmex. However, since 2009, when sulfluramid was included in Annex B of the Stockholm Convention on Persistent Organic Pollutants, there has been an intense search for new methods that are efficient in controlling these insects. Among said new methods, biological control using pathogenic fungi has shown promising results in laboratory conditions. The objective of this study, given the context presented, was to assess the potential of the fungi Beauveria bassiana and Trichoderma harzianum in controlling Atta sexdens. Colonies of A. sexdens were exposed to the fungi by means of formulated baits provided in a foraging chamber, or of suspensions sprayed on the fungus garden, and had their behavioral changes recorded for 21 days. For both formulations, concentrations of 10 and 20% (w/w) of the fungi being studied were used. The results allowed concluding that baits containing 10 and 20% (w/w) of the fungi B. bassiana and T. harzianum were not efficient in controlling colonies of A sexdens. On the other hand, spraying suspensions of 20% (w/w) of B. bassiana and 10% and 20% (w/w) of T. harzianum was efficient and resulted in 100% mortality of the colonies 11, 9 and 7 days after application, respectively. These findings indicate that the fungi B. bassiana and T. harzianum are promising as agents for the control of A. sexdens colonies, when sprayed on the fungus garden, although there are still some challenges as to their use related to the development of technologies for the application of the pathogen.


2021 ◽  
Author(s):  
Xingbo Bian ◽  
Ling Dong ◽  
Yan Zhao ◽  
He Yang ◽  
Yonghua Xu ◽  
...  

Abstract Background Ginseng red skin root syndrome (GRS) is one of the most common ginseng diseases. It leads to a severe decline in ginseng quality and seriously affects the ginseng industry in China. However, as a root disease, the characteristics of GRS rhizosphere microbiome are still unclear. Methods The amplicon sequencing technology, combined with bioinformatics analysis, was used to explore the relationship between soil ecological environment and GRS. Results There were significant differences in the diversity and richness of soil microorganisms between the rhizosphere with different degrees of disease, especially between healthy ginseng (HG) and heavily diseased groups. We also found that bacterial communities underwent multiple changes between complex stability and simple instability in different ginseng rhizospheres through the established interaction networks. The GRS group also had more competition with each other and ecological niche separation than the HG group. The fungal community's stability decreased significantly in the early stages of the disease, followed by the formation of a stable and complex fungal community. The GRS groups significantly increased interspecies cooperation and ecological niche overlap in the fungal network than the HG group. Microbes closely related to potential pathogenic fungi were also identified according to the interaction network, which provided clues for looking for biological control agents. Finally, the Distance-based redundancy analysis (dbRDA) results indicated that total P (TP), available K (AK), available P (AP), catalase (CAT), invertase (INV) are the key factors that influence the microbial communities. Conclusions This study collectively analyzed the changing characteristics in ginseng rhizosphere and provided the basis for soil improvement and biological control of field-grown ginseng.


2002 ◽  
Vol 68 (7) ◽  
pp. 3416-3423 ◽  
Author(s):  
T. H. Nielsen ◽  
D. Sørensen ◽  
C. Tobiasen ◽  
J. B. Andersen ◽  
C. Christophersen ◽  
...  

ABSTRACT Cyclic lipopeptides (CLPs) with antibiotic and biosurfactant properties are produced by a number of soil bacteria, including fluorescent Pseudomonas spp. To provide new and efficient strains for the biological control of root-pathogenic fungi in agricultural crops, we isolated approximately 600 fluorescent Pseudomonas spp. from two different agricultural soils by using three different growth media. CLP production was observed in a large proportion of the strains (approximately 60%) inhabiting the sandy soil, compared to a low proportion (approximately 6%) in the loamy soil. Chemical structure analysis revealed that all CLPs could be clustered into two major groups, each consisting of four subgroups. The two major groups varied primarily in the number of amino acids in the cyclic peptide moiety, while each of the subgroups could be differentiated by substitutions of specific amino acids in the peptide moiety. Production of specific CLPs could be affiliated with Pseudomonas fluorescens strain groups belonging to biotype I, V, or VI. In vitro analysis using both purified CLPs and whole-cell P. fluorescens preparations demonstrated that all CLPs exhibited strong biosurfactant properties and that some also had antibiotic properties towards root-pathogenic microfungi. The CLP-producing P. fluorescens strains provide a useful resource for selection of biological control agents, whether a single strain or a consortium of strains was used to maximize the synergistic effect of multiple antagonistic traits in the inoculum.


2019 ◽  
Vol 112 (4) ◽  
pp. 1581-1586
Author(s):  
Huifang Guo ◽  
Yufeng Qu

Abstract Compared with the numerous natural enemies against insect pests that have been identified, the commercialization of natural biological control resources remains very limited. To increase the use of natural enemies for biological control, determining how to improve the low efficacy, slow speed, and high cost of natural enemies is very important. Mediterranean species of The whitefly, Bemisia tabaci (Gennadius) (Hemiptera: Aleyrodoidea), increasingly threatens many crops in China, and control primarily depends on chemical insecticides. Here, the effect of ethanol extracts from two plants, Agrimonia pilosa (Ledeb) (Rosales: Rosaceae) and Melia azedarach (Linn) (Meliaceae: Melia), on predominant natural enemies of B. tabaci was investigated using a leaf dipping or spraying method. The results showed that the ethanol extract of A. pilosa significantly improved the infectivity of the fungus Isaria javanica (Friedrichs & Bally) (Ascomycota: Hypocreales), and the mortality of whiteflies caused by the combination of fungus (105 spores/mL) with the extract of A. pilosa (2 mg/mL dried powder of A. pilosa containing 0.0942 mg/mL total polyphenols) was 81.6%, which was significantly higher than that caused by the fungus only. However, the ethanol extract of M. azedarach had no effect on fungus infectivity. Additionally, insecticide tolerance of the predator Pardosa pseudoannulata was also significantly improved by the extract of A. pilosa. The longevity of the parasitoid Encarsia formosa was not affected by the extracts. These findings indicate that the extract of A. pilosa played a dual role that included improving pathogenic fungi infectivity and insecticidal tolerance of a predator and thus could be a synergist in the biological control of B. tabaci.


Author(s):  
Xing-eng Wang

Abstract Drosophila suzukii (Matsumura) is native to East Asia but has widely established in the Americas and Europe, where it is a devastating pest of soft-skinned fruits. It has a wide host range and these non-crop habitats harbor the fly which then repeatedly reinvades crop fields. Biological control in non-crop habitats could be the cornerstone for sustainable management at the landscape level. Toward this goal, researchers have developed or investigated biological control tactics. We review over 100 studies, conducted in the Americas, Asia and Europe on natural enemies of D. suzukii. Two previous reviews provided an overview of potential natural enemies and detailed accounts on foreign explorations. Here, we provide an up-to-date list of known or evaluated parasitoids, predators and entomopathogens (pathogenic fungi, bacteria, nematodes, and viruses) and summarize research progress to date. We emphasize a systematic approach toward the development of biological control strategies that can stand alone or be combined with more conventional control tools. Finally, we propose a framework for the integrated use of biological control tools, from classical biological control with host-specific Asian parasitoids, to augmentative and conservation biological control with indigenous natural enemies, to the use of entomopathogens. This review provides a roadmap to foster the use of biological control tools in more sustainable D. suzukii control programs.


2015 ◽  
Vol 1 (2) ◽  
pp. 1-11
Author(s):  
Islam Rizk ◽  
Mohamed Amaar ◽  
Ibraheim Ibraheim ◽  
Abdel-Hameed Othman

Author(s):  
Ahamedemujtaba V. ◽  
Shripad Kulkarni

<div><p><em>Trichoderma</em><em> is a promising candidate for the biological control of plant pathogenic fungi. While planning the application of antagonistic Trichoderma strains for the purposes of biological control, it is very important to consider the environmental parameters affecting the bio-control agents in the soil. A series of abiotic and biotic environmental parameters has an influence on the bio-control efficacy of Trichoderma. The major bottleneck of bio-pesticides is the shelf life and inconsistent performance. In order to overcome this problem, the present study the liquid formulation was used to increase the shelf life of Trichoderma. Oils like Canole oil, paraffin oil, soya bean oil, Neem oil and Glycerol and their combination of paraffin oil and glycerol, paraffin oil and Soya bean oil, Canola oil and Glycerol, and Paraffin oil and Neem oil were used, among which Canola oil + Glycerol based formulation and Paraffin oil based formulation with 3.00 x 104 Cfu/ml and 2.00 X 104 Cfu/ml viable conidia showed extended shelf life of twelve months of storage.</em></p></div>


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