Temporal progress of roselle (Hibiscus sabdariffa L.) leaf and calyx spot disease (Corynespora cassiicola) in Guerrero, Mexico

2020 ◽  
Vol 102 (4) ◽  
pp. 1007-1013
Author(s):  
Santo Ángel Ortega-Acosta ◽  
José Antonio Mora-Aguilera ◽  
Ciro Velasco-Cruz ◽  
Daniel Leobardo Ochoa-Martínez ◽  
Santos Gerardo Leyva-Mir ◽  
...  
Keyword(s):  
Hibiscus Sabdariffa ◽  
Corynespora Cassiicola ◽  
Spot Disease ◽  
Temporal Progress

scholarly journals First Report of Corynespora Leaf Spot on Patchouli Caused by Corynespora cassiicola in China

Plant Disease ◽  
2010 ◽  
Vol 94 (12) ◽  
pp. 1508-1508 ◽  
Author(s):  
X. Y. Chen ◽  
C. Sui ◽  
B. C. Gan ◽  
J. H. Wei ◽  
Y. K. Zhou
Keyword(s):  
Leaf Spot ◽  
Control Measures ◽  
Economic Losses ◽  
Leaf Spot Disease ◽  
Commonwealth Mycological Institute ◽  
Corynespora Cassiicola ◽  
Manihot Esculenta Crantz ◽  
First Report ◽  
Spot Disease ◽  
Potted Plants

Patchouli (Pogostemon cablin (Blanco) Benth.) is mainly cultivated in Southeast Asia as a medicinal shrub and a source of patchouli oil used in perfumery. In 2008, a leaf spot disease was observed on patchouli plants grown on most farms (some farms had 99% incidence) in Wanning, the predominant cultivation location in the Hainan Province of China. The disease usually began at the tip of leaves, the main veins, or small veinlets. Severely irregular-shaped dark brown leaf spots expanded over 5 to 10 days, eventually causing infected leaves to abscise. The time from initial leaf lesions to abscission usually took 1 month. The disease was usually most severe in April and May, causing significant economic losses along with quality losses to patchouli oil extracted from leaves. To isolate the causal pathogen, diseased leaves were collected in August 2008 from a farm of the Hainan Branch Institute of Medicinal Plant Development in Wanning, surface sterilized in 75% ethanol for 1 min, transferred to potato dextrose agar (PDA), and incubated at 28°C for 14 days. Single-spore cultures of three isolates were obtained and identified as Corynespora cassiicola (Berk. & Curt.) Wei. on the basis of morphological and physiological features (1). Genomic DNA was extracted from all the cultures. The internal transcribed spacer (ITS) region of the rDNA was amplified using primers ITS1 (5′-TCCGATGGTGAACCTGCGG-3′) and ITS4 (5′-TCCTCCGCTTATTGATATGC-3′). Amplicons were 546 bp (GenBank Accession No. HM145960) and had 99% nucleotide identity with the corresponding sequence (GenBank Accession No. GU138988) of C. cassiicola isolated from cassava (Manihot esculenta Crantz). To satisfy Koch's postulates, 50-day-old potted plants in a tent were sprayed until runoff with a spore suspension (1 × 106 spores/ml) prepared from 10-day-old cultures. Using this spray method, one isolate was inoculated separately onto nine leaves of three potted plants. The potted plants were covered with plastic bags to maintain high humidity for 48 h and then placed outside under natural environmental conditions (temperature 20 to 28°C). Another nine leaves of three potted plants, sprayed only with sterile water, served as noninoculated control plants. Leaf spot symptoms similar to those on diseased field plants appeared after 7 days on all inoculated plants. C. cassiicola was reisolated from all inoculated test plants. No symptoms were observed on the control plants. To our knowledge, this is the first report of C. cassiicola causing a leaf spot disease on patchouli in China. Other previous reports of this disease were from Cuba (2). This pathogen has also been reported previously to be economically important on a number of other hosts. On patchouli plants, more attention should be given to prevention and control measures to help manage this disease. References: (1) M. B. Ellis. Dematiaceous Hyphomycetes. Commonwealth Mycological Institute: Kew, Surrey, England, 1971. (2) I. Sandoval et al. Cienc. Tec. Agric., Prot. Plant. 10:21, 1987.

scholarly journals Patogenicidade de Corynespora cassiicola a diferentes espécies de plantas

2003 ◽  
Vol 28 (2) ◽  
pp. 193-194 ◽  
Author(s):  
Flávia A. Cutrim ◽  
Gilson S. Silva
Keyword(s):  
Lycopersicon Esculentum ◽  
Vigna Unguiculata ◽  
Cucurbita Pepo ◽  
Carica Papaya ◽  
Abelmoschus Esculentus ◽  
Hibiscus Sabdariffa ◽  
Corynespora Cassiicola ◽  
Commelina Benghalensis ◽  
Capsicum Annum ◽  
Vernonia Cinerea

Avaliou-se, em condições de casa de vegetação, a patogenicidade de dois isolados de Corynespora cassiicola, obtidos de tomateiro (Lycopersicon esculentum), a abóbora (Cucurbita pepo), aceroleira (Malpighia glabra), caupi (Vigna unguiculata), mamoeiro (Carica papaya), maxixe (Cucumis anguria), pimentão (Capsicum annum), quiabeiro (Abelmoschus esculentus), soja (Glycines max), tomateiro e vinagreira (Hibiscus sabdariffa) com o objetivo de selecionar plantas que possam ser utilizadas em sistemas de rotação de culturas, nas áreas produtoras de tomate. Duas plantas daninhas, trapoeraba (Commelina benghalensis) e assa peixe (Vernonia cinerea), comuns em tomatais, foram incluídas nos testes para se avaliar sua importância como fontes de inóculo. As plantas reagiram diferentemente ao patógeno, sendo a maioria suscetível aos dois isolados do fungo. Sugere-se que o tomateiro não deva ser cultivado consorciado ou muito próximo a plantios de abóbora, maxixe, pimentão, quiabeiro e vinagreira. O controle das invasoras como C.benghalensis e V. cinerea é de fundamental importância para a redução do inóculo no campo.

scholarly journals Control químico del manchado de hojas y cálices de jamaica en Guerrero, México

2019 ◽  
Vol 45 (1) ◽  
pp. 38-43
Author(s):  
Santo Ángel Ortega-Acosta ◽  
Daniel Leobardo Ochoa-Martínez ◽  
Santos Gerardo Leyva-Mir ◽  
Ciro Velasco-Cruz ◽  
José Antonio Mora-Aguilera ◽  
...  
Keyword(s):  
Hibiscus Sabdariffa ◽  
Corynespora Cassiicola

RESUMEN El manchado de hojas y cálices de la jamaica, causado por Corynespora cassiicola, se considera la principal limitante fitosanitaria del cultivo de jamaica (Hibiscus sabdariffa) en el Estado de Guerrero, México, causando pérdidas significativas de la producción. Para su control, se evaluó la efectividad biológica de diversas substancias químicas (convencionales y alternativas) durante los ciclos de producción 2014 y 2015. El estudio se realizó en los municipios de Ayutla y Tecoanapa, Guerrero, bajo condiciones de campo y presión natural de inóculo. Las substancias químicas (tratamientos), se aplicaron a intervalos de 7 y 14 días. En cada tratamiento, se registró la severidad en hojas y cálices, así como el peso fresco y seco de cada unidad experimental. El ensayo se estableció bajo un diseño bloques al azar con cuatro repeticiones. Para el análisis de los datos se realizó un análisis de varianza y pruebas de separación de medias (Tukey-Kramer, α=0.05). La menor severidad de la enfermedad y mayor peso fresco y seco de cálices se obtuvo en plantas tratadas con mancozeb, clorotalonil y benomilo alternado con oxicloruro de cobre.

scholarly journals Escalas logarítmicas diagramáticas para evaluar la severidad del manchado de hojas y cálices de jamaica

2016 ◽  
Vol 34 (3) ◽  
Author(s):  
Santo Angel Ortega-Acosta ◽  
Ciro Velasco-Cruz ◽  
Javier Hernández-Morales ◽  
Daniel Leobardo Ochoa-Martinez ◽  
Javier Hernández-Ruiz
Keyword(s):  
Hibiscus Sabdariffa ◽  
Corynespora Cassiicola

<p>El manchado de hojas y cálices en jamaica (Hibiscus sabdariffa L.), inducido por Corynespora cassiicola, actualmente es considerada la principal enfermedad de este cultivo en México. Dada su importancia, es necesario contar con un método estandarizado para cuantificar la severidad de la enfermedad. Por lo anterior, el objetivo del presente estudio consistió en desarrollar y validar dos escalas logarítmicas diagramáticas para cuantificar ésta enfermedad. Para ello, se colectaron hojas y cálices de jamaica infectados de manera natural en plantaciones comerciales del estado de Guerrero, y se calculó la severidad real de cada uno de éstos órganos. Las escalas propuestas, diseñadas con el programa 2LOG, comprenden seis clases, en hojas: 0=0, 1=(&gt;0-2-4), 2=(&gt;4-7-12), 3= (&gt;12-19-29), 4= (&gt;29-42-57) y 5=(&gt;57-70-≤100); en cálices: 0=0, 1=(&gt;0-3-5), 2=(&gt;5-10-18), 3=(&gt;18-30-46), 4=(&gt;46-63-77) y 5=(&gt;77-87-≤100). Asimismo, se verificó la exactitud, precisión y reproducibilidad de las estimaciones. Se hizo una evaluación en hojas y cálices sin utilizar las escalas, y otras dos evaluaciones utilizando las escalas, a intervalos de siete días. Los evaluadores mostraron mejores grados de exactitud, precisión y reproducibilidad con el uso de las escalas. Los resultados sugieren que las escalas propuestas son apropiadas para estimar la severidad del manchado de hojas y cálices en jamaica.</p>

Sign in / Sign up

Export Citation Format

Share Document