THE HUNT for new gene material on the international breeding scene has spread to eastern Asia, with the United States Department of Agriculture (USDA) investigating Asian wheat lines for novel genes to defend against head blight.
Fusarium head blight (FHB) is a fungal disease infecting the heads and seed of cereal grain crops.
The infection is favoured by wet conditions during flowering and grain fill and can cause yield reductions and quality defects in grain including discoloured and shrivelled kernels, depressed seed weights, reduced seed quality and vigour and production of fungal toxins.
The USDA believes Asian wheat may offer genetic material for shoring up the defenses of wheat against Fusarium garminearum fungi that cause Fusarium head blight disease.
There is a concern at USDA that FHB causing species of F. graminearum will overcome the resistant sources currently in play in US varieties.
American researchers are seeking new sources of FHB resistance from exotic wheat lines from China, Korea and Japan.
These lines include "landrace" populations, which are domesticated plants that have changed little since the advent of modern plant breeding.
Of 87 total Asian landrace accessions tested in greenhouse trials, 26 showed high levels of FHB resistance, while grain evaluations showed that 15 of those had exceptionally low levels of mycotoxin contamination, which is produced during disease development.