@article{choquette_weldekidan_brewer_davis_wisser_holland_2023, title={Enhancing adaptation of tropical maize to temperate environments using genomic selection}, volume={6}, ISSN={["2160-1836"]}, url={https://doi.org/10.1093/g3journal/jkad141}, DOI={10.1093/g3journal/jkad141}, abstractNote={Abstract}, journal={G3-GENES GENOMES GENETICS}, author={Choquette, Nicole E. and Weldekidan, Teclemariam and Brewer, Jason and Davis, Scott B. and Wisser, Randall J. and Holland, James B.}, editor={Lipka, AEditor}, year={2023}, month={Jun} }
 @article{butoto_brewer_holland_2022, title={Empirical comparison of genomic and phenotypic selection for resistance to Fusarium ear rot and fumonisin contamination in maize}, volume={7}, ISSN={["1432-2242"]}, url={https://doi.org/10.1007/s00122-022-04150-8}, DOI={10.1007/s00122-022-04150-8}, abstractNote={GS and PS performed similarly in improving resistance to FER and FUM content. With cheaper and faster genotyping methods, GS has the potential to be more efficient than PS. Fusarium verticillioides is a common maize (Zea mays L.) pathogen that causes Fusarium ear rot (FER) and produces the mycotoxin fumonisin (FUM). This study empirically compared phenotypic selection (PS) and genomic selection (GS) for improving FER and FUM resistance. Three intermating generations of recurrent GS were conducted in the same time frame and from a common base population as two generations of recurrent PS. Lines sampled from each PS and GS cycle were evaluated in three North Carolina environments in 2020. We observed similar cumulative responses to GS and PS, representing decreases of about 50% of mean FER and FUM compared to the base population. The first cycle of GS was more effective than later cycles. PS and GS both achieved about 70% of predicted total gain from selection for FER, but only about 26% of predicted gains for FUM, suggesting that heritability for FUM was overestimated. We observed a 20% decrease in genetic marker variation from PS and 30% decrease from GS. Our greatest challenge was our inability to quickly obtain dense and consistent set of marker genotypes across generations of GS. Practical implementation of GS in individual small-scale breeding programs will require cheaper and faster genotyping methods, and such technological advances will present opportunities to significantly optimize selection and mating schemes for future GS efforts beyond what we were able to achieve in this study.}, journal={THEORETICAL AND APPLIED GENETICS}, author={Butoto, Eric N. and Brewer, Jason C. and Holland, James B.}, year={2022}, month={Jul} }
 @article{boomsma_santini_west_brewer_mcintyre_vyn_2010, title={Maize grain yield responses to plant height variability resulting from crop rotation and tillage system in a long-term experiment}, volume={106}, ISSN={["1879-3444"]}, DOI={10.1016/j.still.2009.12.006}, abstractNote={Research emphasizing slower plant growth and delayed maturity in continuous maize (Zea mays L.), no-till (MM–NT) systems has often led to the conclusion that lower grain yields in this environment are associated with reduced plant heights. Yet prior research has shown that early-season and mature plants are not always shorter in MM–NT systems, suggesting that overall plant height may not be an accurate morphometric indicator of decreased yield in MM–NT environments. Given that plant-to-plant morpho-physiological uniformity is strongly associated with higher yield in maize, we hypothesized that greater plant height variability would provide a better agronomic explanation for yield loss in MM–NT environments than overall plant height reductions. This 14-year study primarily examined the effects of crop rotation {maize–soybean [Glycine max (L.) Merr.] and continuous maize} and tillage system (no-till and moldboard plow) on the yield, 4-week plant population, and 4- and 8-week plant height and plant height variability of a single maize cultivar. Due to sizeable year-to-year variation, actual crop response means for the MM–NT; maize–soybean, no-till (MB–NT); and continuous maize, moldboard plow (MM–PL) treatment combinations were expressed relative to the accompanying means for the maize–soybean, moldboard plow (MB–PL) treatment. In numerous years, the MM–NT system exhibited reduced actual and relative yields and lower 4- and 8-week plant heights compared to the other treatment combinations. Both actual and relative 4- and 8-week plant height variability were rarely greatest for the MM–NT treatment, and in only a few years were actual and/or relative plant density lowest for this system. However, single-factor regression analyses between relative yield and the aforementioned relative agronomic measures revealed that a decline in relative MM–NT yield was most strongly associated with an increase in relative 4-week plant height variability. Multi-factor regression analyses between relative yield, relative 4-week plant height variability, and various weather parameters suggested that this strong inverse relationship was potentially a manifestation of (i) non-uniform germination, emergence, and early seedling growth and (ii) later-season intra-specific competition. Regression analyses between relative 4-week plant height variability and various weather parameters suggested that phenomenon (i) was potentially promoted by cool and moist or warm and dry pre-plant weather conditions while phenomenon (ii) was possibly encouraged by low precipitation and/or high temperatures during rapid stem elongation. While MM–NT systems should be managed to limit plant density reductions and minimize growth and developmental delays, increased focus should be placed on minimizing the occurrence of plant-to-plant variability in these environments.}, number={2}, journal={SOIL & TILLAGE RESEARCH}, author={Boomsma, Christopher R. and Santini, Judith B. and West, Terry D. and Brewer, Jason C. and McIntyre, Lauren M. and Vyn, Tony J.}, year={2010}, month={Jan}, pages={227–240} }