By Minerva Baumann
Biologist lands NSF award to study ‘miracle trees’
New Mexico State University researcher Donovan Bailey received an $861,269 National Science Foundation grant to develop plant breeding markers and to investigate the evolution of gene expression between species of the “miracle trees,” a genus of plants found in the tropics that hold great potential for sustainable agriculture.
“These are lesser-known crops in the tropics whose association with nitrogen fixing bacteria make them particularly intriguing,” Bailey said. “They also are multipurpose crops, often representing key elements in sustainable agriculture that are fundamental to production gains in mainstream crops grown in impoverished regions with little access to expensive manufactured fertilizers.”
Bailey, an associate professor of biology in the College of Arts and Sciences, and his team are studying the genome characteristics of the genus of tropical, nitrogen-fixing trees and shrubs called Leucaena. They provide protein-rich leaves for use in animal feed, green manure used as nitrogen-rich fertilizer, and rapidly renewable woody biomass for construction, fuel wood and biofuels. The unusually high protein content of their leaves has helped earn the names “miracle tree” and “alfalfa of the tropics.”
“These are mostly native to central Mexico, but they are planted around the world for multipurpose agriculture,” Bailey said. “In these areas, people typically use alley cropping systems where they’ll have a row of these plants interspersed with corn or gourds or other crops that require extra fertilizer for high yields.”
The goal of the project is to investigate how plant gene expression changes through time and in association with diversification of species. There are 24 nitrogen-fixing species of small trees and shrubs in the genus. Over the course of the grant, researchers will sequence, assemble and compare sets of expressed genes from all species of Leucaena.
“One of the nice things about this particular project is that these plants have been grown for thousands of years by peoples of central Mexico, particularly as a food source,” Bailey said. “The connection between New Mexico and Mexico, in particular Oaxaca and Puebla where Mayan and other cultures had used these plants for thousands of years, garners a lot of student interest. They’re excited about how people have used these plants historically and how they’re being used in modern times.”
The Mid-Career Award from NSF’s Plant Genome Research group funds Bailey’s work as the principal investigator, a postdoctoral fellow in bioinformatics and graduate students. The project also includes the implementation of a new laboratory course to advance interest in and the understanding of plant genome research among students.
“We’re going to use this in a laboratory class, guiding students through a cutting edge set of experiments designed to investigate changes in gene expression over time and under different treatments,” Bailey said
Researchers and students will investigate broad patterns of transcriptome size variation and identify some of the specific changes that have been associated with speciation through geographic isolation in comparison to hybrid speciation associated with genome duplication. The data generated also will be used to develop molecular markers for plant breeding and other studies.
“We will conduct insect feeding trials to identify genes and broad metabolic pathways associated with insect resistance and susceptibility among different species of the plant,” Bailey said.