is originally from Huxley, IA. He studied plant biology at the University of
Nebraska – Lincoln, graduating with honors in 2011. He is currently pursuing a
doctoral degree in plant breeding and genetics at Purdue University. His
graduate studies are focused on understanding the genetic regulation abiotic
in maize and sorghum.
Climate extremes of excess heat, drought and flooding continue to
challenge global agriculture and food security. If modeling studies are
accurate, climate variability and drought will be a more prevalent occurrence
in the future affecting not only grain yield but also stressing water
resources. It is critical to breed for improved climate resilience in
agronomic crops and understand the genetic mechanisms conferring adaptation to
water limited environments.
Sorghum is an important crop grown in drought prone environments
around the world and an important crop model for studying plant adaptation to
water-limited environments. Sorghum breeders have been successful in
developing drought tolerant sorghum hybrids using stay-green as a
phenotype. The ability of annual crop species to delay senescence or
“stay-green” throughout the grain filling period has been associated with
increased yield, decreased lodging, and stalk rot resistance in sorghum.
Genetic analyses of stay-green in sorghum suggest the trait is
controlled by four to six loci that have been integrated into commercial
programs by marker-assisted breeding.
The goal of our research is to characterize the genetic
architecture of stay-green in maize. Maize exhibits substantial
genetic variation for stay-green. We evaluated the Nested
Association Mapping (NAM) populations of maize and testcross hybrids with PHZ51
for variation in stay-green in multi-location trials. Joint
linkage mapping was used to identify multiple QTL
for stay-green across several linkage groups with sources
of stay-green alleles coming from diverse genetic backgrounds.
Comparisons between maize and sorghum for map positions of
these stay-green QTL indicate that two of the major loci occur in
syntenous regions. Identification and integration
of stay-green genes into commercial programs provides the opportunity
to sustainably enhance the productivity of maize and sorghum in drought
Additionally, our research examines the genetic regulation of
premature senescence mutants and characterizing the genetic relationships of
sink-inhibition and hyper-senescence. B73, when the ear is covered or
removed thus removing the sink, prematurely senescence around 700GDD post
anthesis. We are conducting genetic experiments using the NAM population to
characterize this phenotype and understand the underlying genetic regulation.