Potenciales agentes de biocontrol de las principales enfermedades de poscosecha del kiwi en Argentina

Abstract

El objetivo de este trabajo fue identificar enfermedades del fruto de kiwi en poscosecha, conocer sus agentes causales y disponer de métodos de control alternativos que minimicen el uso de agroquímicos. El uso de microorganismos antagonistas ofrece una alternativa complementaria de escasos antecedentes y no explorada en Argentina. Se identificaron enfermedades fúngicas a partir de frutos enfermos y se seleccionaron potenciales antagonistas desde la micoflora asociada al filoplano, fruto y suelo del cultivo de kiwi. La capacidad antagónica se evaluó <i>in vitro</i>. Se identificaron como agentes causales de podredumbres a <i>Botrytis cinerea</i>, <i>Alternaria alternata</i> y <i>Pestalotiopsis</i> sp. Los antagonistas seleccionados fueron <i>Epicoccum nigrum</i> y <i>Trichoderma harzianum</i>. Las cepas de <i>T. harzianum</i> presentaron efecto antagónico reduciendo significativamente la expresión de la enfermedad. Existen hongos saprobios que pueden utilizarse en el manejo integrado de enfermedades del kiwi.

There is little information about diseases of Kiwi fruit in postharvest. It is necessary to know their causal agents and alternative control methods to minimize the use of agrochemicals. Antagonistic microorganisms offer a complementary alternative to analyze. The objectives of this study were to identify postharvest diseases and select antagonists to be used as biocontrol agents. Microorganisms were isolated from diseased fruits and pathogenicity tests were performed. Potential antagonists were selected from micoflora associated to phyloplane, fruit and soil cultivation. The antagonistic capability was assessed <i>in vitro</i>. <i>Botrytis cinerea</i>, <i>Alternaria alternata</i>, and <i>Pestalotiopsis</i> sp. were identified as causal agents of kiwi rot. <i>Epicoccum nigrum</i> and three strains of <i>Trichoderma harzianum</i> were selected as antagonists to perform biocontrol bioassays under in vitro conditions. <i>T. harzianum</i> strains tested showed antagonistic effect when compared with the controls. This saprophytes fungi could be used into an integrated kiwi diseases management.