Credit: Kimberly Homer

Now that scientists have finished farming the human genome, they are turning far afield for new ventures. Several genome projects that will begin this year are quite literally rooted in the field: grapevines, citrus and peach trees, and even the humdrum broccoli.

The grape is one of the most economically important fruit crops in the world, and yet the biology of grapevines is relatively unknown, says Australian researcher Mark Thomas, who chairs the International Grape Genome Project. The group has recently released a white paper outlining research goals and is seeking scientists to join the project. Sequencing the grape genome could improve crop yield, fruit and wine quality, and resistance to pests and diseases.

Plant genome research is expected to get a boost when the US National Plant Genome Initiative releases its five-year plan for 2003–2008. The plan calls for detailed genetic analysis of “key plant species,” which officials have thus far declined to name.

Some genome projects that appear ready to bear fruit include the peach tree, viewed as the best candidate for deep genetic sequencing. The peach, which has a relatively small genome, could serve as a model for a wide range of trees, says Mikeal L. Roose of the University of California-Riverside. “We don't have a good model for fruit trees, and the peach is related to almost all the important fruit and nut trees,” he says.

Citrus researchers, meanwhile, are juiced up about a proposal to establish an international citrus genome steering committee. Spanish researcher Vicente Conejero has offered to host a meeting to prioritize genome projects of interest to citrus researchers and discuss an open-access collaborative citrus genome database.

Brassica, a family of plants including broccoli and cabbage, is the subject of another international project. The plants may offer insight into polyploidy, one of the stranger genetic characteristics of plants—and one that can make plant genomes hard to study, says Ian Bancroft of the John Innes Center in Norfolk, UK.

Several of the schemes were announced in January at the eleventh annual Plant and Animal Genomes Conference in San Diego. The meeting allows agricultural researchers to be exposed to a wide variety of work in other species, says meeting organizer Stephen R. Heller. “You might call it a place where a lot of cross-pollinating occurs.”

Some researchers argue that comparing one plant's sequence to a model genome hastens analysis of specific genes. But because there is significant genetic diversity, others question whether model plants will have much value.

Many plant genome researchers also say finding funding for genome projects can be difficult. “Agricultural genomics is the Rodney Dangerfield field of science,” says Heller. “It gets no respect.” The US National Science Foundation is investing $50 to $60 million in plant genome research, he says. “But that money represents just a day of work on the human genome project.”