Potato (Solanum tuberosum) as a food source and culinary ingredient varies is the fourth most produced noncereal crop in the world. Among multiple biotic stresses, late blight caused by Phytophthora infestans is the most destructive disease. Control of this pathogen is usually by the synthetic fungicides which have been fueled by the public concern about toxicity and environmental impact and development of pathogens resistance. Biological control agents (BCAs) seems the potentially alternative to these pesticides, biological disease control is now recognized and constitute an important tool in integrated pest management. BCAs strains should be able to protect the host plant from pathogens and fulfill the requirement for strong colonization. Bacteria such as Bacillus, Pseudomonas and Streptomyces and fungi such as Trichoderma and Penicillium were the most reported as a BCA against P. infestans using different direct antagonistic mode on the pathogen (via e.g. parasitism, antibiosis, or competition) or via exerting their biocontrol activity indirectly by induction in the plant of an induced systemic resistance to the pathogen. In this study, we present an overview and discussion of the use of beneficial microbes (bacteria and fungi) as novel BCAs for biocontrol of P. infestans.
Part of the book: Agro-Economic Risks of Phytophthora and an Effective Biocontrol Approach
The genus Phytophthora with more than 100 described species and 58 officially recognized, phylogenetically distributed in ten clades, are important pathogenic oomycete chromists that cause important diseases in agricultural crops, trees and forests worldwide. This genus is known as \"The Plant Destroyer” which causes great economic losses with costs between 2 and 7 billion dollars per year in agricultural systems and unquantifiable losses in natural ecosystems. The host plants of the genus Phytophthora can vary from a wide range in some species to only one host, however, the host plants of the new species are still being determined and therefore the range continues to expand, that makes control exceedingly difficult. Plant damage can range from alterations in roots, fruits, trunks, stems, foliage and crown to invasive processes in highly susceptible species. Considering the wide range of hosts and organs that can be affected by Phytophthora, the use of endophytic microorganisms for the biocontrol of this phytopathogen can be an alternative to avoid losses of both crops and forests worldwide. Endophytes are microorganisms that live inside plant tissues without causing disease under any circumstances. The fact that endophytic microorganisms are able to colonize an ecological niche similar to that of some plant pathogens qualifies them as potential biocontrol agents. This chapter describes the endophytic bacteria and fungi isolated from different plant species that have shown antagonistic activity against different species of Phytophthora, as well as the metabolites isolated from these microorganisms that have shown fungicide activity and other biocontrol strategies (enzyme production, siderophores, substrate competition, among others) against Phytophthora.
Part of the book: Agro-Economic Risks of Phytophthora and an Effective Biocontrol Approach