TARGETING ARTHROPOD-BORNE PATHOGENS: AN APPROACH FOR FOOD DISEASE MANAGEMENT AND FOOD SECURITY ESTABLISHMENT

Abstract

As part of its food security strategy, Qatar is devoting great efforts to expand natural resources, upsurge production, and try to reach self-sufficiency. Over the past years, Qatar has implemented various strategies to boost the production of agricultural goods, including vegetables, poultry, fish, eggs, and red meat. Qatar's vision for food security is not in its infancy. It dates back to 2008 with the establishment of the Qatar National Food Security Program (QNFSP).The program was designed to reduce dependence on food imports and enhance national self-sufficiency. It aimed to achieve this by implementing strategies for the efficient use of agricultural resources. Qatar's food security vision is not at its infancy. It dates back to 2008 with the establishment of the Qatar National Food Security Program (QNFSP). The program was designed to reduce dependence on food imports and enhance national self-sufficiency by implementing strategies for the efficient use of agricultural resources. However, several factors including desert climate, extreme temperatures, scarce rainfall, and limited fertile soil pose significant challenges to crop cultivation, threatening food security, not only in Qatar, but also worldwide. Insect pests and vector-borne pathogens have, also, been identified as significant global threats to crops and, consequently, to the agricultural sector, which is a critical pillar of food security. Despite its importance, insect pests in agricultural lands have not been yet extensively explored in Qatar, and data on insect vectors and the pathogens that they carry remains scarce. As such, one part of this study focused on running an "insect survey" to explore the insect pest landscape in agricultural ecosystems, particularly in agricultural greenhouses, in Qatar in order to identify microbes harbored in the collected insects. Being a promising insect control strategy, we then assessed the use of diet interventions as a novel approach for insect pest control using the fruit fly model organism. To do so, we specifically altered the insect diet by supplementing it with either caffeine or the indigestible fiber methylcellulose (MC). Finally, we tested the effectiveness of using diet interventions as crop protectants in an agricultural greenhouse setting. For the first part of the study, our findings revealed the presence of 42 insect species in greenhouse sectors during the study period. The metagenome of one of those 42 insects, the whitefly Trialeurodes vaporariorum, was further analyzed and revealed many microbes that either serve as symbiotic microorganisms to protect whiteflies against pathogens or as potential pathogens that cause damage to crops. For the second part of the study, our findings demonstrated that oral intake of a dose-specific caffeine-containing sugar diet led to a significant alteration in the fly gut environment, evidenced by microbial dysbiosis, increased generation of reactive oxygen species level, associated with an upregulation of immune deficiency pathway-dependent antimicrobial peptide genes, all of which culminated in, rendering the flies more vulnerable to bacterial infections and reducing their lifespan in both infected and non-infected conditions. Likewise, feeding on MC-containing diet induced significant changes in the fly gut environment, including "food stagnation," microbiota remodeling, activation of immune responses, alteration of peptide hormone expression and metabolic processes. Translated into the field, our findings exhibited a clear reduction in Trialeurodes vaporariorum population count/an increase in mortality rates when modified diets were introduced into the studied greenhouse sectors. Taken together, the outcome of this project provides additional insight into the insect pests landscape in agricultural greenhouses in Qatar, and introduces a novel insect control approach to improve integrated pest management strategies both nationally and internationally, paving the way towards optimized agricultural practices, a boost in crop production, and food security achievement