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Background: Peru is considered the third largest exporter of mango in the world and Piura is the first mango producing region representing 68% of the national production; however, the fungus Lasiodiplodia theobromae has been associated with dieback and the presence of cankers in mango cultivation, reducing fruit production and quality. Objective: To evaluate sustainable alternatives for in vitro and in vivo control of L. theobromae in mango, using products based on copper sulfate pentahydrate and a liquid biofertilizer. Methodology: Treatments were applied: T0 (Control), T1 (Vacun-Q organic 0.35 mL100 mL-1), T2 (Vacun-Q organic 0.175 mL 100 mL-1), T3 (Phyton 27® 0.35 mL100 mL-1), T4 (Phyton 27® 0.175 mL100 mL-1), T5 (Biol 10%) and T6 (Biol 20%). Radial growth and mycelial growth inhibition percentage (GIP) of the pathogen were evaluated in the in vitro phase with poisoned media, and necrotic area progression was assessed in the in vivo phase on mango leaves. Results: At 72 h after inoculation, treatments T3, T5 and T6 showed the lowest radial growth of L. theobromae, statistically equal to each other and inferior to the control that completed its development in the Petri dish; likewise, they showed 100% GIP. Five days after inoculation of mango leaves, T5 and T6 presented the smallest necrotic areas with 1.44 cm2 and 1.61 cm2 respectively, followed by T4 with 1.64 cm2 and T2 with 1.69 cm2 compared to the control with 2.05 cm2. Implications: In view of the constant restrictions of active molecules, sustainable and innocuous alternatives for humans and the environment are sought for the control of L. theobromae. Conclusion: Treatments T5 and T6 based on liquid biofertilizers showed to be effective in the in vitro and in vivo control of L. theobromae.

Background: Pasteuria penetrans is a nonculturable bacterium that obligately parasitizes several species of phytopathogenic nematodes. Unknown endogenous female, plant or microbial reproductive factors are indispensable for multiplication and endospore formation of P. penetrans. Objective: To characterize P. penetrans endospores by 16S rRNA gene sequencing in samples from infected adult female Meloidogyne javanica and microbiota of infected and uninfected adult female M. javanica with P. penetrans by high-throughput sequencing of the V4 hypervariable region of the 16S rRNA gene. Methodology: Infected roots were collected from grapevines; fresh infective juvenile nematodes (J2) were extracted for P. penetrans endospore fixation and inoculation into tomato plants. Genomic and metagenomic DNA from infected and uninfected adult females of M. javanica was extracted for sequencing by sequencing the V4 region of the 16S rRNA gene of P. penetrans and its bacterial microbiome. The generated sequences were processed using bioinformatics software for analyses of alpha and beta diversity indices of the bacterial microbiome. Results: An amplicon of 550 base pairs with 98% identity and homology to P. penetrans was obtained. The taxonomic profile revealed the highest bacterial diversity and richness in the microbiota related to infected adult females, with Proteobacteria occurring in both samples between 45 and 83%, followed by Firmicutes, Actinobacteria and Bacteroidetes with 19, 11 and 8% respectively at the phylum level. Likewise, the most abundant genera associated with the native microbiota of the adult nematode were identified as Pseudomonas, Flavobacterium and Chitinophaga at 82.5, 15 and 2%, respectively. In infected females, Paenibacillus, Pasteuria, Pseudomonas and Streptomyces were recorded with 45, 7, 6 and 5% respectively, the most abundant. Implications: The results suggest the existence of bacterial genera in infected M. javanica females involved in the in vivo development of P. penetrans endospores. Conclusions: This would reveal a reduction of Pseudomonas dominance favoring the colonization of different bacteria that cohabit with P. penetrans, being this change in the microbial composition a possible factor that favors the multiplication of P. penetrans endospores within the host.

En Piura el cacao criollo blanco, tiene un gran reconocimiento en el mercado internacional por la calidad del producto. En zonas cacaoteras se viene presentando la muerte regresiva de plantas. Los objetivos del presente estudio fueron describir la sintomatología, identificar el agente causal de la muerte regresiva y determinar su rango de hospedantes. Se realizó descripción de los síntomas en raíces, tallo y parte aérea. El aislamiento del patógeno se obtuvo del suelo y raíces por el método de pétalos de clavel. La identificación se efectuó mediante observación de las características morfométricas del patógeno. Se realizó pruebas de patogenicidad inoculando suspensión de zoosporas a una concentración de 104zoosporas/ml, dirigidas al cuello y raíces de plántulas de cacao blanco. Para el rango de hospedantes se emplearon frutos y plántulas de diferentes especies cultivadas en el país. En árboles frutales de cacao blanco de Piura se observó necrosis de ramas apicales, gomosis, pudrición de raíces y corona, y muerte de la planta. La caracterización morfológica y las pruebas de patogenicidad permitieron identificar el agente causal de la enfermedad como Phytophthora palmivora. Los frutos y plántulas inoculadas como: papa, sandia, papaya, berenjena, mango, naranja, piña, pimiento, tomate, manzana, algodón y ají se comportaron como susceptibles a P. palmivora.

El banano (Musa sp) es un cultivo muy importante en el desarrollo socioeconómico del Perú. La enfermedad de la pudrición blanda viene causando pérdidas económicas. El objetivo fue aislar e identificar el agente causal de la pudrición blanda en banano e implementar alternativas de manejo. Las bacterias fueron aisladas del pseudotallo con síntomas de pudrición blanda de 11 zonas productoras del valle del Chira. La prueba de patogenicidad se realizó en segmentos de pseudotallos y en hijuelos de banano. Ocho aislamientos fueron caracterizados cultural, morfológica y bioquímicamente: Todos los aislamientos tuvieron forma de bacilo, fueron Gram negativos, con flagelos perítricos y las colonias formaron cavidades en medio Cristal Violeta Pectato (CVP). Las pruebas bioquímicas mostraron una reacción positiva a la catalasa, hidrólisis de gelatina, fermentación de glucosa y lactosa, y tolerancia al NaCl 5%. Sin embargo, en medio TSI (Triple azúcar de hierro) y sensibilidad a la eritromicina solo los aislados A2M, A3Ma, A5Mall, A7VF, A9Sa y A10 reaccionaron positivamente y los aislados A6Q y A11Sal negativamente. El crecimiento a 28, 30, 36, 37 y 45 ºC fue positivo para los ocho aislados, a excepción de A6Q y A11Sal no desarrollaron a 45 ºC. Las características culturales, pruebas bioquímicas y de patogenicidad permitieron identificar seis aislados como Pectobacterium chrysanthemi y dos como P. carotovorum subsp. carotovorum. El manejo de la enfermedad se basa en el uso de hijuelos certificados, adecuada fertilización, aplicaciones de materia orgánica, agentes biocontroladores y control del insecto picudo.

El banano Musa spp. (Musaceae) es un cultivo tropical perenne de mayor consumo en el mundo, las principales regiones productoras son; Asia (54,1%), América (25,5%), África (18,4%). En Perú, Piura participa con el 72% del volumen total de las exportaciones de banano orgánico. En los últimos años en Perú y en otras zonas productoras del mundo, se viene presentando los síntomas de necrosis en los haces vasculares del pseudotallo ocasionando la muerte temprana de plantas en producción. El objetivo de este estudio fue identificar los principales patógenos fúngicos asociados a la necrosis vascular del banano. La identificación de los hongos aislados del pseudotallo, rizoma y raíces se realizó a través de claves taxonómicas. Los síntomas externos de la enfermedad fueron amarillamiento y necrosis de las hojas desde el borde hacia la nervadura central, colapso del peciolo y muerte de la planta. Los síntomas internos fueron necrosis en los haces vasculares y lesiones necróticas internas en rizoma y raíces. Por sus características morfométricas los aislados fúngicos se identificaron como; Fusarium oxysporum, F. verticillioides y F. solani. Para el control de esta enfermedad se recomienda implementar un plan de manejo integrado.

Background: In Peru, the Kent variety mango, is the most exported fruit and socioeconomic interest in the country, traditionally produced under conventional fertilization; however, its productivity is affected due to the increase in production costs mainly of fertilizers. Objective: To evaluate the effect of the application of compost and biol on the productive variables of the mango crop var. Kent. Methodology: The following treatments were evaluated: T0: control; T1: compost 5 t ha-1; T2: compost 15 t ha-1; T3: biol 5%; T4: biol 10%; T5: compost 5 t ha-1 + biol 5%; T6: compost 5 t ha-1 + biol 10%; T7: compost 15 t ha-1 + biol 5% and T8: compost 15 t ha-1 + biol10%. The variables evaluated were: polar fruit diameter (DPF-mm), equatorial fruit diameter (DEF-mm), diagonal fruit diameter (DDF-mm), average growth rate per day (TCPD-mm day-1), number of fruits harvested per panicle (NFCP), fruit weight (PF-g), yield per plant (RP-kg plant-1) and yield per hectare (RHA-t plant-1). An ANOVA and cluster analysis were carried out. Results: Cluster analysis formed four groups: G-I (T8, T2 and T7), G-II (T1, T5 and T6), G-III (T4) and G-IV (T3 and T0). Implications: Organic foliar and edaphic fertilization is presented as an alternative to conventional and environmentally friendly fertilization. Conclusion: G-I with the highest organic fertilization presented the highest values in the variables tested. In addition, T8 outperformed the control by 132% for the RHA variable.

Piura es la región con mayor producción de banano orgánico en el Perú; sin embargo, la enfermedad post cosecha de la pudrición de la corona ha generado grandes pérdidas económicas. Por lo cual, se planteó los siguientes objetivos: evaluar la eficacia de biofungicidas in vitro e in vivo para el control de esta enfermedad. Los productos usados fueron: extracto de orégano, ácido cítrico; ácido ascórbico, bioflavonoides; biofertilizante y aceite del árbol de té. In vitro se utilizó el método del “medio envenenado”. In vivo, se inocularon a frutos con suspensiones de conidias a 1 x 104 UFC mL-1 de los fitopatógenos Thielaviopsis paradoxa y Colletotrichum musae. Se prepararon los biofungicidas según la dosis comercial. Se aplicaron los productos y se inocularon los hongos con asperjadores manuales. Los clústeres de banano con tratamiento se embalaron en cajas de cartón de 18,4 kg y fueron embaladas incubándose a 13 °C durante 18 días y 4 días en cámara de maduración con gas etileno. En in vitro los biofungicidas: extracto de orégano (1450 ppm) y ácido cítrico (2825 ppm) obtuvieron 100% inhibición en el crecimiento del micelio de T. paradoxa y C. musae. En in vivo los frutos el menor índice de severidad lo fue para el biofungicida extracto de cítricos (4275 ppm) registrándose 0,0% frente a T. paradoxa y C. musae.

En Perú, la zona productora de banano orgánico más grande es el valle del Chira. Sin embargo, la alta incidencia del daño conocido como “Mancha Roja” en banano ocasiona pérdidas económicas a los pequeños productores. Este estudio tuvo como objetivo identificar taxonómicamente a la especie que causa este daño. Se hicieron colectas en fundos de banano orgánico en Huangalá, Querecotillo y Salitral. Se identificaron a los especímenes adultos tomando en cuenta los caracteres morfológicos. Según las claves propuestas concluimos que se trata de la especie Chaetanaphothrips signipennis (Bagnall) y que es la única especie responsable del daño conocido como “Mancha Roja” en banano y no por un complejo como reporta la literatura local. Conocer estos resultados es fundamental para un adecuado manejo del cultivo, principalmente para estrategias de control de plagas.

Background: Passion fruit (Passiflora edulis S.) is a tropical fruit of socio-economic interest in Peru, used as an ingredient in the food industry, esthetics and medicine. However, this crop has a low germination power, so it is necessary to carry out pre-germination treatments to increase the germination percentage and the initial development of the seedlings. Objective: to evaluate the effect of different biostimulants at 12 h and 24 h of hydration on passion fruit seed germination. Methodology: passion fruit seeds of large and round fruits, free of pathogens, were collected. The aryl-free seeds were treated: T0 (distilled water), T1 (sulfur 25 g/10 L), T2 (sulfur 50 g/10 L), T3 (biol 3%), T4 (biol 5%), T5 (cinnamon 25%), T6 (cinnamon 50%), T7 (buttermilk 25%) and T8 (buttermilk 50%) for 12 h and 24 h imbibition. The variables evaluated were: water absorbed, imbibition rate (IR), germination percentage (GP), germination speed (GS), germination index (GI), first day of germination (FDG). Results: The highest water absorption occurred in the first 9 hours. Treatments T4, T5 and T6 significantly improved the GP, GS, GI, FDG at 12 h imbibition. However, at 24 h imbibition these values decreased. GP presented a high positive correlation with GS and GI. Likewise, GS presented a high negative correlation with FDG. Implications: The use of biostimulants increases germination. Conclusions: Cinnamon extract at 25% and 50%, and biol 5% at 12 h of imbibition have significantly improved the variables evaluated compared to imbibition at 24 h. The positive correlation between the variables indicates a direct relationship between them.

El limón sutil es un cultivo de alta demanda e importancia en el desarrollo socioeconómico en Perú, empleándose mayormente fertilizantes inorgánicos que generan incrementos constantes en los costos de producción, siendo necesario el uso de alternativas orgánicas e inocuas para su producción. El objetivo fue evaluar el efecto de diferentes dosis de biol o biofertilizante, y su correlación en los parámetros productivos y de calidad en el cultivo de limón sutil. Se evaluaron cuatro tratamientos: T0 (testigo: manejo convencional), T1 (Biol 10%), T2 (Biol 20%) y T3 (Biol 30%) aplicados cada 15 días, evaluando los siguientes parámetros: 1) productivos: diámetro del fruto (DF), grosor de cáscara (GC), peso del fruto (PF), rendimiento por ha (RHa) y 2) calidad: acidez (AD), porcentaje de sólidos solubles (PSS), pH, zumo o jugo de limón (ZL). Se realizó análisis de correlación, análisis de componentes principales-ACP, un ANOVA, y se analizó la relación Beneficio/Costo. En el ACP se obtuvo dos componentes: C1 (71.40%) y C2 (11.80%) explicando el 83.20% de la variabilidad. El C1 explica la mayor variabilidad y agrupó variables: G-I (ZL, AD), G-II (DF, GC, PSS) y GIII (PF, RHa). Los tratamientos con Biol 10%, 20%, 30% en ZL, AD (G-I) presentaron los mejores resultados (P < 0.05); el T2 presentó los mayores valores de PF y RHa, y fue el tratamiento más rentable (B/C=3.84). El Biofertilizante es una alternativa para reducir el uso de fertilizantes sintéticos y los costos de producción. El biofertilizante al 20% resultó más rentable y mejoró variables evaluadas.

Background: The aguaymanto has aroused great interest in both the national and international markets for its different uses: aesthetic, medicinal, nutritional and gastronomic. However, agronomic management strategies for this crop with commercial potential are unknown, resulting in low yields and profitability. Objective: To evaluate the effect of different doses of Biogen 1 biostimulant (Bg) and planting distances (PD) on the production and economic analysis of aguaymanto. Methodology: Two factors were evaluated: planting density and dose of biostimulant, resulting in 6 treatments: T1- control (250 ml Bg/200 L + 1m x 1m); T2 (250 ml Bg/200 L + 1.5m x1.5m); T3 (500 ml Bg/200 L + 1m x 1m); T4 (500 ml Bg/200 L + 1.5m x 1.5m); T5 (750 ml Bg/200 L + 1m x 1m) and T6 (750 ml Bg/ 200 L + 1.5m x 1.5m), using a randomized complete block design. The following production parameters were evaluated: number of fruits per plant-NFP, fruit weight-FW (g), fruit diameter-FD (cm), yield per plant-YPP (kg/plant), yield per hectare-YPHA (kg ha-1). Results: T6 had the best yields per plant; however, in the yield per hectare and in the economic analysis, T5 performed better. The correlation in NFP was positive on FD, YPP and YPHA; also, FW with respect to FD and YPP. FD was positively correlated with YPP. However, YPP presented a very weak correlation with YPHA. Implications: Proper use of biostimulants and planting distance increases crop yields. Conclusion: The T6 treatment improved the parameters evaluated per plant, and T5 improved YPHA and the B/C ratio. This positive correlation indicates the directly proportional effect between the parameters

Background: Peru has become the leading exporter of table grapes focusing its production in the Piura and Ica regions. However, most of the young vineyards (

Background: The main problem in grapevine cultivation is root-attachment nematodes cause serious yield problems in most crops worldwide. Through their different infection mechanisms these nematodes synthesize and secrete a mixture of protein-based effectors that they use to penetrate the root, migrate and develop into giant root feeding cells in host plants. The use of new molecular tools such as MALDI TOF/TOF (Matrix-Assisted Laser Desorption/Ionization - Time-Of-Flight) mass spectrometry and PCR (Polymerase Chain Reaction) technique have allowed us to know these proteins and genes in different microorganisms. Objective: To characterize the root-knot nematode Meloidogyne javanica by sequencing the 18S rRNA gene from infected root samples and the effector proteins of juvenile (J2) and adult (J4) stage of M. javanica by MALDI TOF/TOF shotgun proteomics dual mass spectrometry. Methodology: Infected roots of grapevine crop were collected to extract fresh galls and J2 of M. javanica, then inoculated on tomato plants. J4 of M. javanica were used for genomic DNA extraction and sequencing at the 18S rRNA gene level. The J2 and J4 stages of M. javanica were disinfected with sodium hypochlorite (0.5%) and sterile distilled water for protein extraction and analysis with MALDI-TOF/TOF. Finally, the sequences obtained were processed with ProteinPilot™ and Protein BLAST software for the identification of effector proteins of M. javanica. Results: The nematode M. javanica was molecularly identified by PCR amplification of the 18S rDNA gene M. javanica with an identity percentage of 98% from infected root samples and by MALDI TOF/TOF mass spectrometry, effector protein sequences were identified such as: Beta-1,4-endoglucan and polygalaturonase, identified from J2, and expansin B2, CLAVATA3/ESR, Pectate lyase and Chorismato mutase from J4, involved in the different infection processes. In addition, we were able to identify 49 nematode non-effector proteins in both stages related to conserved biological development. Implications: The results indicate the existence of effector proteins related to root gill formation. Conclusions: This study confirms that dual mass spectrometry methodology provides in a rapid and reproducible way a proteomic profile that the galls nematode synthesizes to infect root cells and that can be used in other types of pathogens.

Background: Phaeoacremonium parasiticum is a frequently species associated with "Petri's disease" in young plants of grapevine in Peru. One of the main limitations is the use of fungicides and the limited molecules for its control. In this scenario, biological control is an important alternative to integrate in the management of grapevine diseases. Objective: The objective of the research was to evaluate the in vivo efficacy of native antagonists to P. parasiticum and their growth promoting effect on grapevine. Methodology: Plant material from mother plants (R-110) underwent thermotherapy (52.5°C for 30 min). Subsequently, the antagonists (bacteria and fungi) were inoculated by partial immersion at a concentration of 1x106 cfu ml-1 (Colony forming units) for 3 h; 30 days later, P. parasiticum was inoculated, measuring shoot length before inoculation (SLBI). Seventy days after inoculation (DAI), shoot length (SL), length of necrotic stria (LNS), root dry weight (RDW) and root fresh weight (RFW) were measured. Results: Isolate Tr-5 (Trichoderma spp.) increased SLBI by 68%. Bacillus spp. (Bac-1, Bac-2), Trichoderma spp. (Tr-5) and T. harzianum (T-22) increase >40% SL 70 DDI. Tr-6 (Trichoderma spp.), T-22 and Act-2 (Actinomycete) reduce >50% LNS. Bacillus spp. (Bac-2: Bac-3) significantly increase RFW (59.29%: 49.39%) and RDW (60.41%: 55.08%). Implications: Biological control with native antagonists reduces the development of Petri disease and promotes grapevine growth. Conclusions: The native antagonists show growth-promoting effect and control of LEN caused by P. parasiticum at the nursery stage.