Development of early maturity maize hybrids for resistance toFusarium andAspergillus ear rots and their associated mycotoxins

Abstract

Maize is mainly affected by two fungal pathogens, Fusarium verticillioides and Aspergillus flavus, causing Fusarium ear rot (FER) and Aspergillus ear rot (AER), respectively. Both fungi are of concern to stakeholders as they affect crop yield and quality, contaminating maize grains with the mycotoxins fumonisins and aflatoxins. The easiest strategy to prevent pre-harvest contamination by F. verticillioides and A. flavus is to develop maize hybrids resistant to FER and AER, as well as to their associated mycotoxins. The objective of this investigation was to test 46 F1 hybrids, originated from different Italian, US and Canadian breeding groups, for these important traits and their agronomic performances. All hybrids were planted and artificially inoculated with toxigenic strains of F. verticillioides and A. flavus at two locations in 2017, and the best performing 17 out of 46 were also tested in 2018. Ear rots were present in all hybrids in 2017 and 2018, with percentages ranging from 6.50 to 49.50%, and 5.50 to 45.53%, for FER and AER, respectively. Seven hybrids (PC8, PC15, PC9, PC11, PC14, PC34 and PC17) presented the lowest levels of both diseases considering the overall locations and growing seasons, and three of these (PC8, PC11 and PC14) were also amongst the least mycotoxin contaminated hybrids in 2017. The inbred lines used in hybrid production may provide additional sources of resistance suitable in breeding programs targeting multiple pathogens and their mycotoxins.

Loss of ZmLIPOXYGENASE4 Decreases Fusarium verticillioides Resistance in Maize Seedlings

“…The development of resistant germplasm is one of the major components of the strategy of fungal disease and fumonisin management, but the quantitative nature of these traits and the many environmental variations make the achievement of resistant materials very difficult. For this reason, complete resistance to F. verticillioides infection and fumonisin contamination has not yet been attained [15][16][17][18][19][20]. The identification of candidate genes involved in the host plant resistance mechanisms to this fungus by means of quantitative trait loci (QTL) mapping studies and transcriptomics analysis could provide new insights on the genetic basis of the maize-fungus interaction and hasten the production of resistant hybrids [16].…”

Influence of Endosperm Starch Composition on Maize Response to Fusarium temperatum Scaufl. & Munaut

“…Fusarium ear rot is one of the most devastating and serious diseases of maize worldwide [ 33 , 34 ]. Outbreak of this disease can result in kernels damage, their contamination by mycotoxins, and yield loss [ 35 ]. In the United States and Ontario, Canada, occurrence of FER caused yield losses of 349.2 million bushels in the period 2012–2015 and contributed to mycotoxin contamination estimated at the level of 4529.1 million bushels for maize kernels damaged with toxigenic species [ 36 ].…”

Combining Ability Analysis for Maturity and Yield Attributes in Sweet Corn Across Environments

“…Ravi and Chikkalingaiah (2018) and Revilla et al (2021) also found the ratio of GCA and SCA less than 1 for days to tasseling in maize and indicated the role of non-additive gene action in the control of this trait. However, Zare et al (2017) and Stagnati et al (2020) indicated the additive type of gene action in the control of tasseling and other maturity traits.…”

“…Sweet corn genotypes that performed better under particular environments might not perform well across locations, or changes in the relative ranking of the genotypes are a grave concern to plant breeders (Stagnati et al, 2020;Shojaei et al, 2022). Similarly, testing at various locations for morphological and yield traits is crucial if breeders are interested in germplasm having better adaptability to wider regions (Hassan et al, 2006;Hafiz et al, 2020).…”