Diagrammatic scale for assessment the severity of Cercospora leaf blight on soybean (Glycine max) leaflets

Introduction. Cercospora leaf blight (CLB) caused by Cercospora kikuchii is an endemic soybean crop disease in Argentina. Objective. To develop and validate a scale to quantify the severity of CLB in leaflets of soybean (Glycine max) for the evaluation of foliar fungicides and cultivar trials. Mate...

Descripción completa

Guardado en:

Detalles Bibliográficos
Autores principales:	Miguel Lavilla, Antonio Ivancovich, Antonio Díaz-Paleo
Formato:	article
Lenguaje:	ES
Publicado:	Universidad de Costa Rica 2021
Materias:	Cercospora kikuchii epiphytology pathometric plant pathology disease evaluation Agriculture S
Acceso en línea:	https://doaj.org/article/44131b5b4d4f4b8199fba345f4f12323
Etiquetas:	Agregar Etiqueta Sin Etiquetas, Sea el primero en etiquetar este registro!

id	oai:doaj.org-article:44131b5b4d4f4b8199fba345f4f12323
record_format	dspace
spelling	oai:doaj.org-article:44131b5b4d4f4b8199fba345f4f123232021-12-01T01:34:42ZDiagrammatic scale for assessment the severity of Cercospora leaf blight on soybean (Glycine max) leaflets10.15517/am.v33i1.433381021-74442215-3608https://doaj.org/article/44131b5b4d4f4b8199fba345f4f123232021-10-01T00:00:00Zhttps://revistas.ucr.ac.cr/index.php/agromeso/article/view/43338https://doaj.org/toc/1021-7444https://doaj.org/toc/2215-3608 Introduction. Cercospora leaf blight (CLB) caused by Cercospora kikuchii is an endemic soybean crop disease in Argentina. Objective. To develop and validate a scale to quantify the severity of CLB in leaflets of soybean (Glycine max) for the evaluation of foliar fungicides and cultivar trials. Materials and methods. A diagrammatic scale to assess the severity of CLB on soybean leaflets (Glycine max) was developed. The scale was based on the evaluation of 50 leaflets. The different severity levels of the leaflets were determined according to Weber-Fechner’s stimulus-response law. The proposed scale included severity levels of 1, 4.5, 17.5, 50, 82.2, 95, and 99 %. The validation of the scale was performed by 23 raters (3 experienced and 20 inexperienced) who assessed the severity of CLB on 50 leaflets with and without the use of the scale. Results. The results from the three experienced raters were more precise than those obtained by the inexperienced raters. The scale improved the visual interpretation to assess the severity of CLB for the inexperienced raters, who obtained estimated severity values close to the actual severity values. When the inexperienced raters used the proposed scale to estimate the severity of CLB on leaflets, they were accurate having determination coefficients (R2) between 0.74 and 0.91. According to the absolute errors, the greatest deviation was observed between -2.49 and 2.46. However, these deviations were not significantly different from the population average. To speed the process of cultivar evaluations we also propose the use of scales based on grades. Conclusions. The proposed scale to assess the severity of CLB on leaflets can be used for the assessment of foliar fungicide trials and soybean cultivars. The scale showed specificity for assessing the severity of Cercospora leaf blight (CFB) in soybean leaflets. Miguel LavillaAntonio IvancovichAntonio Díaz-PaleoUniversidad de Costa RicaarticleCercospora kikuchiiepiphytologypathometricplant pathologydisease evaluationAgricultureSESAgronomía Mesoamericana, Vol 33, Iss 1 (2021)
institution	DOAJ
collection	DOAJ
language	ES
topic	Cercospora kikuchii epiphytology pathometric plant pathology disease evaluation Agriculture S
spellingShingle	Cercospora kikuchii epiphytology pathometric plant pathology disease evaluation Agriculture S Miguel Lavilla Antonio Ivancovich Antonio Díaz-Paleo Diagrammatic scale for assessment the severity of Cercospora leaf blight on soybean (Glycine max) leaflets
description	Introduction. Cercospora leaf blight (CLB) caused by Cercospora kikuchii is an endemic soybean crop disease in Argentina. Objective. To develop and validate a scale to quantify the severity of CLB in leaflets of soybean (Glycine max) for the evaluation of foliar fungicides and cultivar trials. Materials and methods. A diagrammatic scale to assess the severity of CLB on soybean leaflets (Glycine max) was developed. The scale was based on the evaluation of 50 leaflets. The different severity levels of the leaflets were determined according to Weber-Fechner’s stimulus-response law. The proposed scale included severity levels of 1, 4.5, 17.5, 50, 82.2, 95, and 99 %. The validation of the scale was performed by 23 raters (3 experienced and 20 inexperienced) who assessed the severity of CLB on 50 leaflets with and without the use of the scale. Results. The results from the three experienced raters were more precise than those obtained by the inexperienced raters. The scale improved the visual interpretation to assess the severity of CLB for the inexperienced raters, who obtained estimated severity values close to the actual severity values. When the inexperienced raters used the proposed scale to estimate the severity of CLB on leaflets, they were accurate having determination coefficients (R2) between 0.74 and 0.91. According to the absolute errors, the greatest deviation was observed between -2.49 and 2.46. However, these deviations were not significantly different from the population average. To speed the process of cultivar evaluations we also propose the use of scales based on grades. Conclusions. The proposed scale to assess the severity of CLB on leaflets can be used for the assessment of foliar fungicide trials and soybean cultivars. The scale showed specificity for assessing the severity of Cercospora leaf blight (CFB) in soybean leaflets.
format	article
author	Miguel Lavilla Antonio Ivancovich Antonio Díaz-Paleo
author_facet	Miguel Lavilla Antonio Ivancovich Antonio Díaz-Paleo
author_sort	Miguel Lavilla
title	Diagrammatic scale for assessment the severity of Cercospora leaf blight on soybean (Glycine max) leaflets
title_short	Diagrammatic scale for assessment the severity of Cercospora leaf blight on soybean (Glycine max) leaflets
title_full	Diagrammatic scale for assessment the severity of Cercospora leaf blight on soybean (Glycine max) leaflets
title_fullStr	Diagrammatic scale for assessment the severity of Cercospora leaf blight on soybean (Glycine max) leaflets
title_full_unstemmed	Diagrammatic scale for assessment the severity of Cercospora leaf blight on soybean (Glycine max) leaflets
title_sort	diagrammatic scale for assessment the severity of cercospora leaf blight on soybean (glycine max) leaflets
publisher	Universidad de Costa Rica
publishDate	2021
url	https://doaj.org/article/44131b5b4d4f4b8199fba345f4f12323
work_keys_str_mv	AT miguellavilla diagrammaticscaleforassessmenttheseverityofcercosporaleafblightonsoybeanglycinemaxleaflets AT antonioivancovich diagrammaticscaleforassessmenttheseverityofcercosporaleafblightonsoybeanglycinemaxleaflets AT antoniodiazpaleo diagrammaticscaleforassessmenttheseverityofcercosporaleafblightonsoybeanglycinemaxleaflets
_version_	1718405955011477504

Diagrammatic scale for assessment the severity of Cercospora leaf blight on soybean (Glycine max) leaflets

Ejemplares similares