Written by: Karyn Houston
Two UC Berkeley scientists have been awarded a 3-year grant to study how to develop strains of corn that use the leaves and stems of the plant in biofuel production.
The $793,000 grant from the Department of Energy looks at how to utilize the tons of leftover “crop residue” left behind after the kernel is used. Dr. Markus Pauly and Dr. Sarah Hake, of the Department of Plant & Microbial Biology in the College of Natural Resources, plan to focus in on the extensive genetic diversity of corn to develop more efficient strains for biofuels.
Corn is the number one feedstock used for ethanol production in the United States. However, only the starch in the kernels is currently used for fermentation to ethanol. Use of the corn kernel is in direct competition with the food and feed industry, Pauly said, and represents only 25% of the typical corn plant currently grown in the U.S.
Pauly and Hake hope to identify and develop strains of corn with higher yields of fermentable sugars that would then allow more of the plant to be used for fuel production.
Currently the U.S. generates more than 75 million dry tons of excess corn material, called “corn stover” that is essentially leftover stems and leaves. This grant aims to enhance the utility of the remaining part of the corn plant, the stem and leaves.
One goal of the grant is to look at the extensive genetic diversity of corn, which is actually greater than that between humans and chimps, Pauly said. The team wants to tap into that genetic diversity for increased biofuel production. It’s all about using the whole plant, not just the sweet kernel. The second goal is to look at mutagenized corn mutants that also have enhanced characteristics for biofuel production.
Pauly and Hake’s grant, entitled "Identification and Genetic Characterization of Maize Cell Wall Variation for Improved Biorefinery Feedstock Characteristics", is part of a larger effort by the DOE and U.S. Department of Agriculture to fund projects that accelerate plant breeding programs.
The goal is to improve biomass feedstocks by characterizing the genes, proteins and molecular interactions that influence biomass production. This science will lay the groundwork for a new class of fuels, called biofuels, derived from lignocellulosic biomass materials – the fibrous, woody and generally inedible portions of plant matter.
The rationale for developing such feedstocks for energy is that less intensive production techniques and marginal or surplus agricultural lands can be used for these crops, thereby avoiding competition with food production on better quality lands.
In order for biofuels to become economically competitive as mainstream fuels, the portion of useable yield must be increased.
Most corn grown in the U.S. today has not been bred for biofuel production. As a result, many of the carefully selected existing traits are not advantageous for biofuel production. Ultimately, this research seeks to develop and demonstrate environmentally acceptable crops for producing large quantities of low-cost, high-quality biomass feedstocks.
Dr. Markus Pauly is an Associate Professor at UC Berkeley and part of the team at the Energy Biosciences Institute. Dr. Sarah C. Hake is an Adjunct Professor at UC Berkeley and Center Director of the USDA Plant Gene Expression Center in Albany, California.