Rm. Clear et al., THE EFFECT OF HULL REMOVAL AND PEARLING ON FUSARIUM SPECIES AND TRICHOTHECENES IN HULLESS BARLEY, Canadian Journal of Plant Science, 77(1), 1997, pp. 161-166
Fourteen samples consisting of three cultivars of hulless barley (Hord
eum vulgare L.), grown commercially in southern Manitoba in 1994, were
examined for levels of Fusarium species and seven fusarium trichothec
ene mycotoxins: deoxynivalenol (DON), diacetoxyscirpenol, 15-acetyldeo
xynivalenol (15ADON), fusarenone-X, HT-2 toxin, neosolaniol and T-2 to
xin. Four fractions from each sample were analysed. These consisted of
kernels with the hulls still attached, kernels whose hulls had been r
emoved at harvest, kernels that had been dehulled in the laboratory us
ing a deawner, and kernels that had been pearled in the laboratory to
60% of their original weight. A composite sample of the hulls, obtaine
d from the laboratory dehulling, was also tested. Mycotoxins were dete
rmined by gas chromatography-mass spectrometry. DON and 15ADON were th
e only trichothecenes detected in this study. The greatest numbers of
propagules of Fusarium spp, and the highest concentrations of DON and
15ADON were found in the hulls. The average concentrations of F. grami
nearum Schwabe and DON in barley were reduced: 90 and 49%, respectivel
y, as a consequence of laboratory dehulling; 95 and 59%, respectively,
as a result of dehulling during harvest; and 99 and 86%, respectively
, as a result of pearling. Results suggest that growing hulless cultiv
ars shows promise for management of mycotoxin problems associated with
FHB.