Researchers at North Carolina State University show that an important gene in maize called HPC1 modulates certain chemical processes that contribute to flowering time, and has its origins in “teosinte mexicana,” a precursor to modern-day corn that grows wild in the highlands of Mexico. The findings provide insight into plant evolution and trait selection, and could have implications for corn and other crops’ adaptation to low temperatures.
“We are broadly interested in understanding how natural variation of lipids are involved in the growth and development of plants, and how these compounds may help plants adapt to their immediate environments,” said Rubén Rellán-Álvarez, assistant professor of structural and molecular biochemistry at NC State and the corresponding author of a paper describing the research. “Specifically, we wanted to learn more about variation in lipids called phospholipids, which consist of phosphorus and fatty acids, and their role in adaptation to cold, low phosphorus, and the regulation of important processes for plant fitness and yield like flowering time.”
Maize grown at higher altitudes, like the highlands of Mexico, needs special accommodations in order to grow successfully. The colder temperatures in these mountainous regions put maize at a slight disadvantage when compared with maize grown at lower elevations and higher temperatures.
“At high elevations, in colder temperatures, it takes longer to make a maize plant due to lower heat unit accumulation — corn needs to accumulate heat or growth units,” Rellán-Álvarez said. “At 10,000 feet (2,600 meters), it takes three times longer to make a maize plant than at lower elevations. To adapt to these special conditions campesinos — smallholder farmers — must plant early in the season and plant deep in the soil; there is very slow but steady growth in earlier months until the rainy season arrives. Over millennia, campesinos have selected maize varieties that can thrive in these special conditions by being able to grow at low temperatures and flower early before the colder months arrive in the winter.”
That’s where the HPC1 gene comes in, the researchers say. In corn varieties grown in low elevations, including most of the corn grown in the United States, the gene breaks down phospholipids that in other species have been shown to bind to important proteins that accelerate flowering time.
“Phospholipids are also important building blocks of cell membranes. All lipids have different shapes and balancing these shapes is what allows membranes to stay intact and helps plants to survive periods of stress,” said Allison Barnes, a postdoctoral researcher in Rellán-Álvarez’s lab and co-first author of the paper.
Source: Read Full Article
