Universidad Nacional Agraria La Molina. Escuela de Posgrado. Maestría en Fitopatología

Universidad Nacional Agraria La Molina. Escuela de Posgrado. Doctorado en Agricultura Sustentable

Stem-end rot (SER) of avocado is caused by several fungal species, and it is presented worldwide. This plant disease currently affects several avocado producer regions in Peru, causing fruit rot, impacting the industry negatively. Research about SER distribution in the canopy of avocado trees is limited. Thus, the present study aimed to compare which areas in the canopy are prone to have more SER in ‘Hass’ avocado harvested fruit in two different coastal areas in Peru. The experiment was conducted in the northern (Barranca) and southern (Cañete) of Lima. ‘Hass’Avocado fruits from both producer areas were collected to identify the causal agent; Lasiodiplodia theobromae was isolated from infected fruits. Identification was conducted based on morphological features and a partial DNA sequence of the translation elongation factor 1-α gene (tef1-α). The results showed that fruits in...

Esta investigación tuvo como objetivo la identificación del agente causal del mildiú de la albahaca y la validación de un método de estimación de la severidad. El patógeno presenta morfométricamente zoosporangióforos monopodiales y ramificados dicotómicamente en ángulo agudo hasta 4,25 veces en la parte terminal, un largo de 320,1 µm; esterigmas cortos de 15,5 µm y de 17,9 µm de largo. Los zoosporangios, ligeramente ovoides con 27,7 µm de diámetro y con 31,9 µm de largo. La estimación de severidad se realizó por el método de Horsfall y Barratt (HB) (Horsfall y Barratt, 1945), por estimación visual directa (VD) y evaluando daño foliar por cada tercio de la planta (TH). La evaluación aleatoria se realizó en tres oportunidades por tres evaluadores, y los valores estimados fueron correlacionados con la severidad real. Para medir la confiabilidad entre evaluadores y m�...

problemas fisiológicos que afectan la calidad del mango a la cosecha y postcosecha en el valle de Yaután, provincia de Casma, departamento de Áncash. Durante la campaña 2021-2022, se visitaron predios con cultivos de mango para observar problemas sanitarios, posteriormente a la cosecha se colectaron frutos de los sectores: Valdivia, Señor de los Milagros, Cerro Castillo, Acoshpampa, Canchapampa, Punchayhuaca, Liza alta, Lagar, Jaihua, y Matua, los cuales fueron llevados al Laboratorio de Fitopatología de la UNALM y se colocaron en cámaras húmedas a 21 °C durante 3 a 4 semanas para incentivar el desarrollo de posibles patógenos en postcosecha. En el campo, durante la floración, cuajado, crecimiento y desarrollo del fruto, el mango es afectado por la mosca de la fruta (Ceratitis sp., y Anastrepha sp.), oidiosis (Oidium mangiferae Berthet), trips y queresas, alterando el tamaño,...

Avocado root rot caused by Phytophthora cinnamomi is one of the main problems affecting avocado (Persea americana) cultivation in Peru, especially at the Chavimochic Irrigation Project. The objective of this study was to evaluate the effect of different Trichoderma strains on the control of Phytophthora cinnamomi in Zutano rootstock under greenhouse conditions. Five isolates of Trichoderma were tested: Trichoderma sp. (Chav01); Trichoderma harzianum (Chavo2); Trichoderma harzianum (UNALM01); Trichoderma viride (UNALM02); and a commercial strain of Trichoderma sp. Evaluations were performed at 30, 45, and 60 days. All isolates colonized the rhizosphere of the avocado. No relation was found between the formation of more Trichoderma colonies and Phytophthora improved control. All strains controlled the root rot, but Chav01 and Chav02 showed the greatest diameter of stem, dry matter in the r...

The flowers blight caused by Botrytis cinerea Pers. is among the most important citrus diseases, especially in cultivars whose flowering coincides with the humid seasons of the year. As a result of the pathogenic features of this fungus and the complex nature of its control, it is necessary to establish a correct plan for the usage of highly efficient fungicides. The study aimed to evaluate the effect of four chemical fungicides, such as Captan (0.25%), Propineb (0.25%), Fludioxonil + Cyprodinil (0.05%), and Iprodione (0.15%); as well as the effect of a biological fungicide, such as Melaleuca alternifolia extract (0.1%), on Botrytis cinerea Pers. Two phases were established: the first, under laboratory conditions of Department of Plant Pathology of National Agrarian University-La Molina (UNALM), evaluated the effect on mycelial inhibition at 1, 3, and 7 days after inoculation with poison...

The present study was conducted in the fields of the Chavimochic irrigation, located in La Libertad Region-Peru. Prodiplosis longifila Gagné (Diptera Cecidomyiidae) is considered the key pest of asparagus and other vegetables cultivation. This study aimed to characterize the presence of this insect pest in asparagus crop under drip irrigation conditions, in order to find the best alternatives for its control. The cultivar most planted in the Chavimochic Irrigation is cultivar UC 157 and that the meteorological conditions of the area are optimal for the production of asparagus; but also for the establishment and reproduction of the insect. The morphology of asparagus is favorable for reproduction of the insect, from larva to adult, since it frequently bracts and flowers at larval stage and establishs itself at the adult stage; at the base of the plant. All experiments conducted, had at l...