Hydroxamic acids (4-hydroxy-1,4-benzoxazin-3-ones)
are present in wild and cultivated members of the family
Poaceae (tribe Triticeae) (Niemeyer et al., 1992).
Significant amount of literature is available on the
differential production of hydroxamic acids in cereals.
The main hydroxamic acids reported from cereals are
DIBOA and DIMBOA (2,4-dihydroxy-7-methoxy-1,4-
benzoxazin-3-one); their distribution with cultivated
Poaceae, however, is uneven (Niemeyer, 1988). While
wheat has both DIMBOA and DIBOA, rye contains
only DIBOA. The significant variation in the amount of
DIBOA and DIMBOA in seedlings of wild Poaceae was
reported by Gianoli and Niemeyer (1998) (Table 3).
These authors reported the correlation between the
amount of hydroxamic acid and resistance to Russian
wheat aphid (Diuraphis noxia) and the greenbug