Hessian fly,
Mayetiola destructor
(Say), is a destructive pest of wheat worldwide and an endemic pest in Tunisia. Two
natural populations of this insect from the North of Tunisia were evaluated, in the field, for their virulence, based on
response developed by bread wheat (
Triticum aestivum
L.) cultivars carrying
H3,
H5,
H6,
H7H8,
H11,
H13 and
H16
resistance genes.
H11,
H13 and
H16 showed a high effectiveness against both populations; therefore, their implication in
Hessian fly breeding programs would be of interest. The level of infestation, as well as the yield loss, was assessed, based
on the percentage of infested plants and variation in growth parameters due to infestation. The percentage of infested
plants, over a 2-yr period in Mateur, averaged 18.82% for durum wheat (
Triticum turgidum
L. subsp.
durum (Desf.) Husn.)
and 32.50% for bread wheat. For the improved durum wheat cv. Karim used as reference, the plant height, number of
internodes, number of productive tillers per plant, and 100-seed weight were negatively affected by infestation, while
the number of tillers per plant was positively affected. Aiming to update information about the annual number of the fly
generations occurring on wheat, we surveyed infestation in Jédéida. At least three Hessian fly generations were detected
on bread wheat and durum wheat. Continued regular surveying of Hessian fly populations in terms of virulence, impact on
yield and annual generations is required for optimal deployment of resistance genes and integrated management of Hessian
fly across all wheat production areas.
