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Abstract Background Maize ( Zea mays L.) is a major cereal crop, with the United States accounting for over 40% of the worldwide production. Corn leaf aphid [CLA; Rhopalosiphum maidis (Fitch)] is an economically important pest of maize and several other monocot crops. In addition to feeding damage, CLA acts as a vector for viruses that cause devastating diseases in maize. We have shown previously that the maize inbred line Mp708, which was developed by classical plant breeding, provides heightened resistance to CLA. However, the transcriptomic variation conferring CLA resistance to Mp708 has not been investigated. Results In this study, we contrasted the defense responses of the resistant Mp708 genotype to those of the susceptible Tx601 genotype at the transcriptomic (mRNA-seq) and volatile blend levels. Our results suggest that there was a greater transcriptomic remodeling in Mp708 plants in response to CLA infestation compared to the Tx601 plants. These transcriptomic signatures indicated an activation of hormonal pathways, and regulation of sesquiterpenes and terpenoid synthases in a constitutive and inducible manner. Transcriptomic analysis also revealed that the resistant Mp708 genotype possessed distinct regulation of ethylene and jasmonic acid pathways before and after aphid infestation. Finally, our results also highlight the significance of constitutive production of volatile organic compounds (VOCs) in Mp708 and Tx601 plants that may contribute to maize direct and/or indirect defense responses. Conclusions This study provided further insights to understand the role of defense signaling networks in Mp708’s resistance to CLA.
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Predictive breeding for maize: Making use of molecular phenotypes, machine learning, and physiological crop models
Maize (Zea mays L.) has been a focus of scientific research and breeding for over a century. It is also one of the most economically important crops in the world, with a value of approximately US$50 billion per year in the United States alone. Additionally, maize has long been the model species of choice for the study and exploitation of hybrid vigor, and it continues to be one of the world's most efficient converters of photosynthetic energy into starch. This review discusses the history and future of maize predictive breeding in the context of both genotype centric methods, and those focusing on genotype × environment × management interactions. Current prediction challenges are highlighted, as well as important advances in technology, methods, datasets, interdisciplinary collaborations, and scientific culture that will enable accelerated progress in predictive maize (and other crop species) breeding for years to come.
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- Award ID(s):
- 1710618
- PAR ID:
- 10140186
- Date Published:
- Journal Name:
- Crop Science
- ISSN:
- 2027-5919
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1002/csc2.20052
