COLLEGE STATION — Tomatoes were ripe this year when the National Science Foundation handed out some $40 million for a massive national plant genome effort paralleled to the human genome project.
A $7.8 million grant will take researchers at Cornell and Texas A&M universities and The Institute for Genomics Research to the innermost parts of the popular fruit in hopes of finding not only how to improve on it but how its genetic functions may help explain other crops. The three-year funding officially begins Oct. 1.
About $1.4 million of that will come to Texas A&M to study what most every consumer wants – a tender, deep red tomato – and how the ripening process develops such.
“We want to understand how the ripening process has evolved – what happens to make a tomato go from a green, baseball-like thing to a soft, red desirable fruit,” said Dr. Jim Giovannoni, Texas Agricultural Experiment Station horticulturist and co-investigator on the project. “That could be related to how the fruit of other plants develop basically.”
Tomatoes are big business in the United States when it comes to vegetable production – leading in value at $1.2 billion for the fresh market in 1997, according to the U.S. Department of Agriculture-Economics and statistics System’s most recent report. Texas fresh tomato growers accounted for about $21.8 million of that.
“There is value in genome projects, especially in agricultural crops,” Giovannoni said. “This represents an opportunity to take the next step into the biological frontier on how genomes are put together and what they control such as disease protection, yields and ripening.”
For his part, Giovannoni will manage about 10 undergraduate through post-doctoral people to first generate 60,000 tomato genes ready for sequencing by TIGR. In total, TIGR will sequence some 100,000 tomato genes that are expressed in all the plant’s tissues from the roots to the leaves, seed, flowers, ripening fruit and “everything we can think of,” Giovannoni said.
The TIGR team will compare the results to find those that are not repeats of each other and form a subset of the non-redundant genes which may number up to 20,000. From there, Giovannoni said, the Texas A&M team will set up DNA chips using a robotic system to spot the genes on glass slides for gene expression analysis. That information, useful to tomato breeders, plant scientists, and biotechnologists who want to know where certain characteristics are controlled, for example, will be made widely available to the public, he said.
“In the end, we may find that some genes are not involved in fruit development but we will also get clues as to when the genes are important, perhaps in cell division, roots, disease-resistance and over-ripening in tomatoes,” he said. Knowing how particular genes work, he said, may help breeders of other crops find similar genetic makeup in other plants.
While Giovannoni’s lab explores tomato fruit ripening, Dr. Steve Tanksley of Cornell, the project’s principal investigator, will manage a $2 million effort to compare the tomato genome to Arabidopsis (a plant standard in biotechnology). Dr. Greg Martin, also of Cornell, will oversee a $1.2 million study of tomato disease resistance. TIGR will receive $3.2 million for their tomato DNA sequencing efforts.
“Tomatoes are extremely amenable to biotechnology,” Giovannoni added. “It’s easy to transfer genes and see what happens in a short amount of time. You can put seed in the ground and have tomatoes in two or three months and they can be grown year round.”
He said the project will yield answers that ultimately can be used by commercial breeders and biotechnologists to develop improved tomato varieties that meet the needs and desires of consumers.