RALEIGH, N.C.—Scientists at the Agricultural Research Service, Plant Science Research Unit at North Carolina State University have discovered chromosome regions responsible for detecting seasonal changes in flowering time (photoperiod response) of maize, which may lead to higher crop yields, improved disease resistance and heartier plants able to withstand severe weather.
Researchers interbred two tropical, photoperiod-sensitive corn lines (one from Mexico; one from Thailand) with two photoperiod-insensitive corn lines from the United States, and grew out hundreds of progeny lines in North Carolina (long day-length summers) and in Florida (short day-length winters). Lines with strong photoperiod response were identified as those flowering much later in North Carolina, compared to Florida. Researchers then genetically mapped all of the lines and identified DNA markers associated with the photoperiod response. The genomic regions carrying the major photoperiod response genes were then identified.
In addition to allowing for improved strains of domestic corn, the research also suggests that the genes controlling the photoperiod response in corn are at least partly distinct than those believed to control photoperiod response in model plant species such as Arabidopsis (Mustard Weed) and rice.
Future studies to pinpoint specific genes involved in the photoperiod response, however, will be necessary to draw definitive conclusions. The results of these future studies should lead to a better understanding of the extent of shared genetic pathways among distinct plant species and provide insights into how such pathways evolve.
