Sorghum (Sorghum bicolor L. Moench) is a C4 species sensitive to the cold spring conditions that occur at northern latitudes, especially when coupled with excessive light, and that greatly affect the photosynthetic rate. The objective of this study was to discover genes/genomic regions that control the capacity to cope with excessive energy under low temperature conditions during the vegetative growth period. A genome-wide association study (GWAS) was conducted for seven photosynthetic gas exchange and chlorophyll fluorescence traits under three consecutive temperature treatments: control (28 °C/24 °C), cold (15 °C/15 °C), and recovery (28 °C/24 °C). Cold stress significantly reduced the rate of photosynthetic CO2 uptake of sorghum plants, and a total of 143 unique genomic regions were discovered associated with at least one trait in a particular treatment or with derived variables.
AMES, Iowa – Organic agriculture practices eschew many synthetic fertilizers and pesticides, putting pressure on crops that conventional farming circumvents. That means an organic farmer who doesn’t use herbicides, for instance, would value crop varieties better suited to withstand weeds.
Enter Thomas Lubberstedt, a professor of agronomy at Iowa State University. Lubberstedt and a team of ISU researchers recently received a four-year, $1 million grant from the U.S. Department of Agriculture to advance organic corn varieties. By the end of the project, the team aims to have identified elite varieties that will improve the performance of corn under organic growing conditions.
“Our main goal is to figure out whether new genetic mechanisms can benefit organic field and sweet corn varieties,” Lubberstedt said. “We want to develop traits that can do well under organic conditions.”
Founded in 1902, the Iowa Crop Improvement Association is a nonprofit organization affiliated with Iowa State University’s College of Agriculture and Life Sciences and designated as the official seed-certifying agency in Iowa.