Abstract
The infection caused by grain mold in rainy season grown sorghum deteriorates the physical and chemical quality of the grain, which causes a reduction in grain size, blackening, and making them unfit for human consumption. Therefore, the breeding for grain mold resistance has become a necessity. Pedigree breeding has been widely used across the globe to tackle the problem of grain mold. In the present study, a population breeding approach was employed to develop genotypes resistant to grain mold. The complex genotype × environment interactions (GEIs) make the task of identifying stable grain mold-resistant lines with good grain yield (GY) challenging. In this study, the performance of the 33 population breeding derivatives selected from the four-location evaluation of 150 genotypes in 2017 was in turn evaluated over four locations during the rainy season of 2018. The Genotype plus genotype-by-environment interaction (GGE) biplot analysis was used to analyze a significant GEI observed for GY, grain mold resistance, and all other associated traits. For GY, the location explained a higher proportion of variation (51.7%) while genotype (G) × location (L) contributed to 21.9% and the genotype contributed to 11.2% of the total variation. For grain mold resistance, G × L contributed to a higher proportion of variation (30.7%). A graphical biplot approach helped in identifying promising genotypes for GY and grain mold resistance. Among the test locations, Dharwad was an ideal location for both GY and grain mold resistance. The test locations were partitioned into three clusters for GY and two clusters for grain mold resistance through a “which-won-where” study. Best genotypes in each of these clusters were selected. The breeding for a specific cluster is suggested. Genotype-by-trait biplots indicated that GY is influenced by flowering time, 100-grain weight (HGW), and plant height (PH), whereas grain mold resistance is influenced by glume coverage and PH. Because GY and grain mold score were independent of each other, there is a scope to improve both yield and resistance together.
Highlights
Sorghum is well-adapted to the harsh conditions of arid and semiarid agroecologies where other crops fail to thrive well
The results showed a significant genotype × environment interactions (GEIs) on both grain yield (GY) and grain mold
The Genotype plus genotype-by-environment interaction (GGE) biplot analysis helped to identify G28 and G21 as the best candidates for GY, whereas G4, G33 were good for grain mold resistance in terms of their mean performance and stability compared to other lines
Summary
Sorghum is well-adapted to the harsh conditions of arid and semiarid agroecologies where other crops fail to thrive well. Grain mold of rainy season grown sorghum is one such disease, which has changed its significance over time (Das et al, 2020) It has become a prominent disease of rainy season sorghum for its devastating effects on grain yield (GY) and quality. It is a common disease in the countries of Asia, Africa, North America, and South America (Frederiksen et al, 1982; Das and Padmaja, 2016). In India, highyielding white grain hybrids are widely grown during the rainy season, which are devastated due to grain mold This is mainly due to the cultivation of short- and medium-duration sorghum cultivars that mature during the rainy days in humid, tropical, and subtropical climates. Grain mold poses health hazards to both human and animals due to the production of mycotoxins and secondary metabolites (Castor and Frederiksen, 1980; Little and Magill, 2009; Audilakshmi et al, 2011)
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
