EFFICIENCY OF THE MICROTUNNEL AND BIOLOGICAL PRODUCTS IN THE PRODUCTION OF POTATO TUBERS (Solanum tuberosum L.) FOR SEED

Potato purple top (PMP) is one of the main phytosanitary problems of potato in Mexico and some other producing regions in the world.The main causal agents of the disease are considered to be phytoplasmas and the bacterium Candidatus Liberibacter solanacearum (CaLso), which are pathogens located in the phloem of the host.Leafhoppers are considered as the vectors of phytoplasmas and the psyllid Bactericera cockerelli as the vector of CaLso.Losses caused by PMP can reach 100% as it reduces yields as well as the quality of the tuber produced.Currently, the management and control of the disease is done by chemical control of the vector with massive applications of pesticides with a great adverse effect on the environment and human health.For this reason, it is considered necessary to generate alternatives to obtain a profitable and sustainable production for the producer, such as the use of resistant or tolerant varieties to the disease, as well as the use of biological products and cultural measures that greatly reduce the use of pesticide applications.The objective of this study was to evaluate the efficiency of the microtunnel and the use of biological products to produce seed-quality tubers.Five treatments were evaluated, two consisted of the use of microtunnels with and without the application of biological products for the control of soil pests and pathogens, two treatments were open field with and without the application of biological products and one treatment was open field without the application of any biological product.The treatments with the use of microtunnels were efficient in producing tubers with 100% sprouting.However, its use as seed for commercial sowing is not recommended if a small percentage of CaLso infection is detected, since it constitutes the primary inoculum for infection in the entire crop, but it is feasible to use it in the production of potatoes for self-consumption.The biological products used have no effect in re-ducing the percentage and intensity of tuber browning caused by CaLso.