Ecological applications of Pseudomonas as a biopesticide to control two-spotted mite Tetranychus urticae: chitinase and HCN production
Journal Title: Journal of Plant Protection Research - Year 2017, Vol 57, Issue 4
Abstract
The two-spotted spider mite (Tetranychus urticae Koch) is an important pest of many horticultural crops. A study was conducted to evaluate the effect of three fluorescent Pseudomonas isolates obtained from rhizospheric soil of tomato (Solanum lycopersicon) in Agadir, Morocco: Q110B, Q036B and Q172B, as potential biological control agents for T. urticae. Both acaricide and repellent activities were assessed on homogenous adult mites. The acaricidal activity test evaluated five concentrations of bacterial suspensions: 0 (control), 102, 104, 106, 108, and 1010 cfu ⋅ ml–1, while only the 1010 cfu ∙ ml−1 concentration of each bacterium was used for the repellent bioassay. The mortality rate and repellentindex were recorded 24, 48 and 72 h after application. Results indicated that the survival rate of T. urticae was reduced (p ≤ 0.01) by all three bacterial isolates compared to control. Within the 24–72 h time period the mortality rates ranged from 8 to 87%, 16 to 99%, and 13 to 89%, for Q110B, Q036B and Q172B isolates, respectively. The isolate Q036B (LC50 = 0.598 cfu ⋅ ml–1) provided higher mortality rates than Q172B and Q110B with LC50 values of 90,846 and 169,585 cfu ⋅ ml–1, respectively. Repellent activity was also the highest with Pseudomonas Q036B having a 71% repellence index at 48 h after application. Regarding the mechanism of action, all three isolates produced hydrogen cyanide, and exhibited protease and cellulose activities, although only Q036B and Q172B had potential chitinase action. Identification analysis showed that the isolates were either Pseudomonas putida (Q172B) or P. fluorescens (Q110B and Q036B). Our results indicate that the P. fluorescens isolate Q036B is a promising candidate for biological control of T. urticae, and has potential to contribute to an integrated pest management program to control this important pest. Then the fruits produced will be qualified as safe for consumers and the environment. The present work was customized to give support for policy decision makers as an agroecological potential meeting needs of industries and ecological balance.
Authors and Affiliations
Redouan Qessaoui, Rachid Bouharroud, Abderrahim Amarraque, Abdelhadi Ajerrar, El Hassan Mayad, Bouchra Chebli, Mokhtara Dadi, Fayssal El Filali, Alan Stuart Walters
Evaluation of some microbial agents, natural and chemical compounds for controlling tomato leaf miner, Tuta absoluta (Meyrick) (Lepidoptera: Gelechiidae)
Solanaceous plants have a great economic impact in Egypt. These groups of plants include potatoes, tomatoes and eggplants. The new invasive pest of tomatoes, Tuta absoluta (Meyrick) causes the greatest crop losses which...
The occurrence of three species of the genus Oscheius Andrássy, 1976 (Nematoda: Rhabditida) in Iran
Due to importance and effectiveness of some entomopathogenic or insect parasitic nematodes in controlling of agricultural pests, or pests of non-agricultural plants, a study was conducted in order to identify the species...
Failure control of Plutella xylostella (Lepidoptera: Plutellidae) and selectivity of their natural enemies to different insecticides
Control failure of pests and selectivity of insecticides to beneficial arthropods are key data for the implementation of Integrated Pest Management (IPM) programs. Therefore, the aim of this study was to assess the contr...
The role of guidelines in pest monitoring and warning systems in integrated pest management
The rules and guidelines for integrated pest management specified in Annex III, sections 2 and 3, state “General principles of integrated pest management”: Harmful organisms must be monitored by adequate methods and tool...
Topical treatment of LdMNPV-infected gypsy moth caterpillars with 18 nucleotides long antisense fragment from LdMNPV IAP3 gene triggers higher levels of apoptosis in infected cells and mortality of the pest
The high efficiency of baculovirus infection is partially explained by the ability of the virus to suppress host defense machinery connected with the apoptosis pathway. Members of the baculovirus gene family, inhibitors...