Guayule, a shrub that yields high-quality, hypoallergenic natural latex, is now easier to genetically engineer, thanks to Agricultural Research Service scientists.

Native to Texas, guayule (pronounced why-YOU-lee) can be processed to yield a milky latex that is free of allergens that can cause severe reactions including anaphylactic shock. An estimated 20 million Americans are allergic to the latex in gloves, condoms and other products made from the most widely used source, the Brazilian rubber tree.

ARS plant physiologist Katrina Cornish, a member of ASPP, leads the guayule research at the ARS Western Regional Research Center in Albany, Calif.

Cornish, along with Christopher J.D. Mau and Mary H. Chapman at Albany, and former Albany researcher Javier Castillón, developed a faster, easier way to move new genes into guayule. Their work opens the way to giving tomorrow's guayule new genes that could boost production of latex, or enhance resistance to a root rot that can attack this otherwise disease-resistant shrub.

The scientists' procedure, patterned after one widely used by researchers elsewhere with other plant species, relies on bathing pieces of guayule leaves in a solution containing a re-worked form of a microbe, Agrobacterium tumefaciens. The microbe, with the experimental genes inside, can slip genes into guayule cells. The leaf pieces are then nurtured to form plantlets.

Cornish's team is apparently the first to use this approach successfully with guayule. An article in the current issue of ARS' Agricultural Research magazine tells more. View it on the World Wide Web at: http://www.ars.usda.gov/is/AR/archive/may99/rubb0599.htm