Pineapple has been cultivated for more than 6,000 years, thriving in water-starved environments. To understand how pineapples grow to be juicy under such conditions, researchers at the University of Illinois at Urbana-Champaign took a closer look at the plant's genes and genetic pathways.

The researchers, led by biology professor Ray Ming, found that pineapple share ancestors with sorghum and rice. Like many plants, the ancestors of pineapple experienced multiple doublings of their genomes, so the researchers tracked the remnants of these "whole-genome duplications" to trace the plant's evolutionary history.

The team found that pineapple uses a special type of photosynthesis called crassulacean acid metabolism (CAM), while most plants use C3 photosynthesis. Ming said that CAM plants use only 20 percent of the water used by typical C3 plants, and CAM plants can grow in dry, marginal lands that are unsuited for most plants. The genome revealed that some genes that contribute to CAM photosynthesis are regulated by the plant's circadian clock genes, which allow plants to differentiate day and night and adjust their metabolism accordingly. "This is the first time scientists have found a link between regulatory elements of CAM photosynthesis genes and circadian clock regulation," Ming said.

For more information, read the news release at the Illinois News Bureau.