Thanatephorus cucumeris (many names, depending on host).

Introduction: T. cucumeris is a pathogen with a worldwide distribution and in Japan alone T. cucumeris is reported to infect 35 orders, 52 families, 125 genera and 142 species of plant (Ogoshi, 1996). Yield and economic losses caused by T. cucumeris have not been determined in the majority of crops and environments. The most comprehensive estimates of losses are available for Rhizoctonia bare patch of wheat in Australia, sheath blight of rice in Asia and cotton seedling disease in the USA. The remainder of the reports cited are for only a few crops in selected regions and in selected years.

1,2,4-Oxadiazole-Based Bio-Isosteres of Benzamides: Synthesis, Biological Activity and Toxicity to Zebrafish Embryo

To discover new compounds with broad spectrum and high activity, we designed a series of novel benzamides containing 1,2,4-oxadiazole moiety by bioisosterism, and 28 benzamides derivatives with antifungal activity were synthesized. These compounds were evaluated against four fungi: Botrytis cinereal, FusaHum graminearum, Marssonina mali, and Thanatephorus cucumeris. The results indicated that most of the compounds displayed good fungicidal activities, especially against Botrytis cinereal. For example, 10a (84.4%), 10d (83.6%), 10e (83.3%), 10f (83.1%), 10i (83.3%), and 10l (83.6%) were better than pyraclostrobin (81.4%) at 100 mg/L. In addition, the acute toxicity of 10f to zebrafish embryo was 20.58 mg/L, which was classified as a low-toxicity compound.

" Surú”

Introducción. A pesar de que los frijoles rojos y negros (Phaseolus vulgaris L.) son los tipos comerciales más comunes en Costa Rica. Los frijoles blancos se comercializan en un nicho de mercado que paga mejores precios por ellos. Para una producción rentable, las personas pro- ductoras requieren variedades de grano blanco más resistentes a los patógenos y con arquitectu- ra de planta erecta. Objetivo. Describir el proce- so de desarrollo y las principales características de la variedad Surú. Materiales y métodos. Esta variedad provino del cruzamiento simple entre la línea blanca mejorada PAN 68 y el cultivar rojo “Bribrí”. Este cruce inicial fue realizado en el 2002 en la Escuela Agrícola Panamerica- na en Honduras. Luego fue evaluada en Costa Rica del 2004 al 2008, por el Instituto Nacional de Innovación y Transferencia en Tecnología Agropecuaria y la Universidad de Costa Rica. La selección de F2 a la F6 se realizó en la Estación Experimental Agrícola Fabio Baudrit Moreno, y luego se sembraron 5 ensayos y 11 parcelas de validación de 1500 m2 cada una, en condiciones de productor, donde se determinaron las caracte- rísticas y desempeño agronómico. La variedad se liberó el 10 de diciembre del 2009 en Guagaral, Buenos Aires, Puntarenas. Resultados. Surú es una variedad de grano blanco con un rendimien- to de hasta 1350 kg.ha-1 bajo manejo del produc- tor, con arquitectura erecta (tipo II-a), resistencia intermedia (valor <5) a Pseudocercospora gri- seola (mancha angular), resistencia al virus del mosaico común (BCMV) (gene dominante I) y al virus del mosaico dorado amarillo (BGYMV) (gen bgm-1 y el QTL SW12), y susceptibilidad a Thanatephorus cucumeris (mustia hilachosa) y Aphelenchoides besseyi (amachamiento) con un valor ≤7. Conclusiones. Debido a sus carac- terísticas agronómicas, Surú es una variedad adecuada para los sistemas de siembra manual (“a espeque”) y semi-mecanizado, empleadas en Costa Rica. Se recomienda su siembra durante la segunda época del año (octubre) en la región Brunca para efectuar la cosecha durante la esta- ción seca (diciembre - enero).

Atividade peroxidásica em feijoeiro comum (Phaseolus vulgaris L.) cv. Aporé na presença de ácido salicílico e Thanatephorus cucumeris

O feijoeiro é cultivado em todas as regiões do país, apresentando grande importância econômica e social, e constitui-se em um dos elementos básicos da alimentação, sendo um dos principais fornecedores de proteínas, ferro e carboidratos. O objetivo deste estudo foi avaliar a indução de proteínas relacionadas à patogênese, de forma específica a enzima peroxidase, em plantas de feijoeiro comum desafiadas com indutores bióticos e abióticos. Para isso, foi borrifado 1 mL de solução de ácido salicílico (AS) 10 mM nas folhas primárias de feijoeiro, e posteriormente estas foram coletadas em quatro tempos: 0, 24, 48 e 72 hai (horas após a inoculação) e armazenadas em freezer -20 ºC para realização das análises bioquímicas. A cultivar apresentou teores de proteínas variando de 0,046 a 0,076 mgP/mL nas plantas testadas com água e inoculadas com o fungo, apresentando pico de proteína 72 hai. Nas plantas testadas com ácido salicílico 10 mM e posteriormente inoculadas com o fungo, os valores variaram de 0,052 a 0,086 mgP/mL, com pico de proteína 24 hai. Os níveis de atividade peroxidásica (POX) variaram de 5,31 a 29,37 UA/mgP nas plantas inoculadas com água e fungo e de 1,17 a 22,83 UA/mgP nas plantas tratadas com ácido salicílico e o fungo. As plantas tratadas com o AS 10 mM e depois inoculadas com o fungo mostraram pico de atividade POX 24 horas após a inoculação do patógeno, enquanto que nas plantas tratadas com água o pico de atividade POX ocorreu 72 horas após a inoculação do patógeno. Os resultados alcançados até o momento sugerem um potencial do ácido salicílico como indutor da resposta de defesa do feijoeiro comum contra o fungo T. cucumeris.

A Fungal P450 Enzyme from Thanatephorus cucumeris with Steroid Hydroxylation Capabilities

ABSTRACT In this study, we identified a P450 enzyme (STH10) and an oxidoreductase (POR) from Thanatephorus cucumeris NBRC 6298 by a combination of transcriptome sequencing and heterologous expression in Pichia pastoris . The biotransformation of 11-deoxycortisol was performed by using Pichia pastoris whole cells coexpressing sth10 and por , and the product analysis indicated that the STH10 enzyme possessed steroidal 19- and 11β-hydroxylase activities. This is a novel fungal P450 enzyme with 19-hydroxylase activity, which is different from the known steroidal aromatase cytochrome P450 19 (CYP19) and CYP11B families of enzymes. IMPORTANCE Hydroxylation is one of the most important reactions in steroid functionalization; in particular, C-19 hydroxylation produces a key intermediate for the synthesis of 19-nor-steroid drugs without a C-19 angular methyl group in three chemoenzymatic steps, in contrast to the current industrial process, which uses 10 chemical reactions. However, hydroxylation of the C-19 angular methyl group remains a very challenging task due to the high level of steric resistance to the C-19 methyl group between the A and B rings. The present report describes a novel fungal P450 enzyme with 19-hydroxylase activity. This opens a new venue for searching effective biocatalysts for the useful process of steroidal C-19 hydroxylation, although further studies for better understanding of the structural basis of the regioselectivity and substrate specificity of this fungal steroidal 19-hydroxylase are warranted to facilitate the engineering of this enzyme for industrial applications.

Web blight (Thanatephorus cucumeris): a new disease on leaves of okra plants

ABSTRACT: In an experiment on organic production of okra (Abelmoschus esculentus (L.) Moench) that was carried out from September 2013 to January 2014, in Manaus, Amazonas state, Brazil, we observed large chlorotic, necrotic, helical, discontinuous, dark or light-brown lesions with partial detachment of the injured area on the adaxial surface of leaves located in the median and basal portions of the plants. A whitish mycelium mantle covers the lesions on the leaves at the abaxial surface at high moisture conditions. Using morphological characteristics, Koch’s postulates, and phylogenetic analyses of the ITS-5.8S rDNA region, we identified that the fungus causing the lesions on the okra leaves was Thanatephorus cucumeris (Frank) Donk (asexual stage of Rhizoctonia solani Kuhn of the anastomosis group AG-1 ID). This is the first report of T. cucumeris causing web blight on okra in Brazil, and probably in the world. So far, T. cucumeris was described on okra only on post-harvest pods rotting and seedlings’ damping off.