Assessment Of Parasitism PDF

ASSESSMENT OF PARASITISM  ASSESSMENT Microbial behavior affecting biocontrol should be studied under natural conditions or those that mimic natural conditions The efficacy of a biocontrol agent depends on the mechanism of action, (conditioning, dose, methods of application),...

ASSESSMENT OF PARASITISM  ASSESSMENT Microbial behavior affecting biocontrol should be studied under natural conditions or those that mimic natural conditions The efficacy of a biocontrol agent depends on the mechanism of action, (conditioning, dose, methods of application), plant pathogens targets (sensitivity), host (cultivar type, physical properties), and environmental conditions (biotic and abiotic factors, chemical residues, nutrient availability, temperature, moisture) ASSESSMENT METHODS OF ESTABLISHING EFFICACY FOR BIOLOGICAL CONTROL 1 Laboratory tests 2 Greenhouse tests 3 Field tests 4 Farm tests  ASSESSMENT 1 Laboratory tests Antagonism assay a s s e s s e s t h e a b i l i t y o f o n e microorganism to inhibit the growth of another through the production of antimicrobial compound  ASSESSMENT 1 Laboratory tests Antagonism assay Dual Culture tests Trichoderma sp. to control Fusarium sp. Evaluate the antagonistic capability. of Trichoderma isolates against F. fujikuroi Suppression effect of Trichoderma spp. against F. fujikuroi in dual culture plate testing, (b) Inhibition effect against F. fujikuroi after seven days of incubation at 28±2°C, Ng, L.C., Ngadin, A. Azhari, M. and Zahari, N.A. 2015. Potential of Trichoderma spp. as Biological Control Agents Against Bakanae Pathogen (Fusarium fujikuroi) in Rice. Asian Journal of Plant Pathology 9 (2): 46-58, 2015  ASSESSMENT 1 Laboratory tests Antagonism assay Antagonistic activity of Bacillus subtilis HK-CSM-1 on mycelial growth of Colletotrichum panacicola Ryu, H., Park, H., Suh, D.-S., Jung, G. H., Park, K., & Lee, B. D. (2014). Biological control of Colletotrichum panacicola on Panax ginseng by Bacillus subtilis HK-CSM-1. Journal of Ginseng Research, 38(3), 215–219. doi:10.1016/j.jgr.2014.05.001  ASSESSMENT 1 Laboratory tests  Feeding trials: Determine if a predator or parasitoid will consume the pest in controlled conditions.  No-choice test  Choice test  ASSESSMENT 1 Laboratory tests  Life table studies: Determine the development, reproduction, and survival rates of a biocontrol agent.  ASSESSMENT 1 Laboratory tests  Host range testing: Check if a potential biocontrol agent attacks only the target pest and not beneficial or non-target species.  ASSESSMENT 2 Greenhouse tests  These are semi-field conditions where the environmental parameters are controlled but more natural than laboratory settings. They offer a middle ground to see if results from lab tests hold up in more realistic conditions.  ASSESSMENT 2 Greenhouse tests  Results showed that neither B. subtilis AP-01 nor T. harzianum AP-001 alone could control the bacterial wilt, but when combined, their controlling capabilities were as effective as a chemical treatment. These results were also similar for damping-off disease when used in combination. In addition, the combined B. subtilis AP-01 and T. harzianum AP-001 resulted in a good frogeye leaf spot control, which was not significantly different from the chemical treatment.  ASSESSMENT 2 Greenhouse tests Leucinodes orbonalis Tranthala flavoorbitalis  ASSESSMENT 3 Field tests  Replicated experiments: Multiple sites or plots are treated with the biocontrol agent and compared to untreated or differently treated plots.  Monitoring: After release, monitor the population densities of the pest and the biocontrol agent over time to assess impact.  ASSESSMENT 3 Field tests Control of naturally occurring rice blast disease was investigated during the dry and wet season in Cambodia. The Trichoderma reduced the blast incidence in the susceptible variety Chou, C., Castilla, N., Hadi, B., Tanaka, T., Chiba, S., & Sato, I. (2019). Rice blast management in Cambodian rice fields using Trichoderma harzianum and a resistant variety. Crop Protection, 104864. doi:10.1016/j.cropro.2019.104864  3 Field tests Reduction rates (mean ± SE) of adult populations of Phyllotreta striolata seven and 14 days after treatment. a Experiment 1 conducted in a field grown with Chinese white cabbages Brassica rapa b. Experiment 2 conducted in a field grown with Chinese cabbages Brassica campestris Yan, X., Han, R., Moens, M., Chen, S., & De Clercq, P. (2012). Field evaluation of entomopathogenic nematodes for biological control of striped flea beetle, Phyllotreta striolata (Coleoptera: Chrysomelidae). BioControl, 58(2), 247–256. doi:10.1007/s10526- 012-9482-y  ASSESSMENT 4 Farm tests  ASSESSMENT 4 Farm tests Bandyopadhyay, R., Atehnkeng, J., Ortega-Beltran, A., Akande, A., Falade, T. D. O., & Cotty, P. J. (2019). “Ground- Truthing” Efficacy of biological control for aflatoxin mitigation in farmers’ fields in Nigeria: From field trials to Commercial usage, A 10-Year study. Frontiers in Microbiology, 10. https://doi.org/10.3389/fmicb.2019.02528  MASS PRODUCTION If biocontrol of plant pathogens is to be accomplished on field-scale, it will be necessary to produce biocontrol agents in the form of spores or other propagules Viable inocula must be produced in an inexpensive medium and cost of production for treatment of large areas must be competitive with that of chemical pesticides  Isolation and Screening for Strain Selection Characterization of Selected Strains Formulation and Delivery for Commercial Use Bonaterra, Anna, Esther Badosa, Núria Daranas, Jesús Francés, Gemma Roselló, and Emilio Montesinos. 2022. "Bacteria as Biological Control Agents of Plant Diseases" Microorganisms 10, no. 9: 1759. https://doi.org/10.3390/microorganisms10091759 STEPS/ SEQUENCE FOR PRODUCTION OF BIOCON AGENTS Discovery and identification of Biocon 1 agents 2 Efficacy test 3 Safety test (user safety, environmental safety and safety of non-target organisms)  STEPS/ SEQUENCE FOR PRODUCTION OF BIOCON AGENTS 4 Test genetic stability of biocontrol agents (during their shelf life, biocontrol agents should not lose their virulence) 5 Study the potential for mass production  STEPS/ SEQUENCE FOR PRODUCTION OF BIOCON AGENTS 6 Formulation of biocontrol agent in a container with chance to enhance their efficacy 7 Test stability and shelf-life 8 Test market potential  STEPS/ SEQUENCE FOR PRODUCTION OF BIOCON AGENTS 9 Evaluation of product 1 0 Return on investment analysis 11 Field trials 1 2 Patent the biological control agent 1 Commercialization and delivery of biopesticide 3 products to the user MASS PRODUCTION Substrates used for mass production of antagonists Wheat (Hadar et al., 1979) Chopped straw moistened by acid mineral solution (Davet et al., 1981) Grain bran (Wells et al., 1972) Wheat bran(Sivab et al., 1984) Barley grains (Abd-Wl Morty et al., 1981) Sand and corn meal (Lewis and Papzvizas, 1988)  MASS PRODUCTION Substrates used for mass production of antagonists Readily available High in stored carbon and energy Provide sufficient fiber to provide some structure to the finished product Factors to be considered to enhance mass production 1. Physical growth conditions - Temperature = 24-29C - Moisture = 55-65% 2. Substrate – where the BCA feeds - Carbon-Nitrogen ratio (C:N) = 20:1 to 40:1 - pH of substrate = 5.5 - 6.5 Factors to be considered to enhance mass production 2. Substrate - Other factors – other nutrient sources to provide specific requirements as needed such as lime for calcium source 3. Incubation - Provide favorable temperature during this period to hasten multiplication of the inoculum  CONSTRAINTS 1. Biocon agents should compete well with chemical pesticides 2. Safety testing is mandatory 3. Assurance that products delivered to the users have a high level of potency and purity 4. Biocontrol agents are living entities therefore, handling, transportation and storage conditions need to be specifically defined. 5. Biocon agents have a short-term expiration date, therefore, expiration date must be carefully examined and placed in the products’ label APPLICATION/ FIELD RELEASE The introduction of antagonists aims to intensify microbial üSeed treatment interaction resulting in control of üSeedling dip disease-causing organisms üSeed-biopriming A potential antagonist is isolated, üFoliar spray application artificially multiplied on media and introduced for microbial ü Soil application/ direct interactions and control of a application particular disease APPLICATION/ FIELD RELEASE The method by which the roots of a seedling are coated with an antagonist Weststeijn (1990) reported that tulip root rot caused by P. ultimum was suppressed by dipping tulip bulbs in Pseudomonas suspension.