She is performing related trials to determine if there are interactions between soil temperature and PGPR strains and between rootstock and PGPR strains. Preliminary results from ongoing field tests show that methyl iodide effectively controls replant disorder in peaches. Compared to trees in control plots, tree trunks in plots treated with methyl iodide and methyl bromide were significantly thicker. Eayre is continuing these tests for another year. This ARS research is collaborative with James Sims and Howard Ohr of the University of California at Riverside and Tri-Cal in Hollister, California.
Replant disorders cause growers serious problems.
Replant stunts the growth of trees and increases the amount of time before fruit can be harvested for the first time. It also causes more trees to die in their first to fifth year of growth. Peach trees planted in soil where peaches had been recently grown grow very slowly for one to several years. Since it is very expensive to let an orchard lie fallow and rotating another crop can take too much time, growers usually fumigate the soil with methyl bromide. This eliminates harmful organisms or pathogens that might be present.