Mungbean G × E interaction unveiling resistance to Cercospora leaf spot through GGE biplot analysis

Area of Science:

• Agricultural Science
• Plant Pathology
• Genetics

Background:

• Cercospora leaf spot (CLS), caused by Cercospora canescens, significantly threatens global mungbean production due to its wide host range and environmental influences.
• Effective control strategies require understanding the complex interactions between mungbean genotypes, pathogen strains, and environmental conditions.

Purpose of the Study:

• To identify and validate mungbean genotypes exhibiting resistance to Cercospora leaf spot (CLS).
• To evaluate the performance of mungbean genotypes across diverse environmental conditions for CLS resistance.
• To leverage genomic selection and statistical models for identifying superior resistant genotypes.

Main Methods:

• Initial screening of 110 mungbean genotypes under controlled conditions, followed by Koch's postulates for disease confirmation.
• Field testing of 16 selected genotypes across four environments over three years.
• Analysis using GGE (Genotype x Environment) biplot and AMMI (Additive Main Effects and Multiplicative Interaction) models to assess genotype-environment interactions (GEI).

Main Results:

• GGE biplot analysis highlighted the critical role of both genetic and environmental factors in determining CLS resistance.
• Two mungbean genotypes, SK-89 (15) and WMB-9 (14), were identified as highly desirable for CLS resistance.
• The study successfully identified ideal testing environments and 'mega environments' for evaluating CLS resistance.

Conclusions:

• Genotype-environment interaction (GEI) analysis using GGE biplot and AMMI models is effective for evaluating CLS resistance in mungbean.
• The identified resistant genotypes SK-89 and WMB-9 provide valuable genetic resources for developing improved mungbean varieties.
• Findings offer crucial insights for optimizing future mungbean breeding programs focused on CLS resistance.