Food Quality & Safety

            February 2009

RESEARCH REINFORCES THE NOW – AFLATOXIN LINK

ALMOND BOARD OF CALIFORNIA-funded research spanning numerous projects over 30 years have demonstrated a link between navel orangeworm (NOW) damage and aflatoxin in reject kernels. Two current ABC-funded projects provide insights into why this occurs.

The first is a study led by Themis Michailides (Plant Pathologist, UC Kearney) with Joel Siegel (USDA-ARS, Parlier) that demonstrates under field conditions both NOW larvae and adults vector or carry spores of Aspergillus — the fungus that produces aflatoxin — and introduces it into the hulls, shells and kernels. This work is also being supported by the USDA Areawide Program for Control of Navel Orangeworm.

This field work corroborates recent lab studies led by Jeffrey Palumbo and others (USDA-ARS, Albany) showing NOW larvae vector Aspergillus spores and increase fungal colonization and resulting aflatoxin.

Other research led by May Berenbaum and Guodong Niu (University of Illinois) demonstrates NOW larvae can tolerate high concentrations of aflatoxin, and helps to explain why there is such a strong link between navel orangeworm activity and aflatoxin. For instance, orangeworm larvae can survive aflatoxin concentrations 100 times higher than those that kill corn earworm larvae. This work shows NOW have an enzyme that breaks down aflatoxin, making it tolerant and well-adapted as a carrier.

This is the first in a series of articles that highlight ABC-funded production research. These results were exhibited at the 36th Almond Industry Conference and included in the 2008 Conference Proceedings.

Last updated February 3, 2009