Is it necessary to apply insecticides to russian wheat aphid resistant cultivars?
2000
Tolmay, V. | Mare, R. (Small Grain Institute. Agricultural Research Council, Bethlehem (South Africa))
Wheat cultivars resistant to Russian wheat aphid (Diuraphis noxia) have been available to fanners in the Free State Province of South Africa since 1992. Resistance conferred by the genes Dnl and Dn2 is known to reduce the percentage of tillers infested with aphids as well as lower the number of Russian wheat aphids per infested tiller. In addition, a dramatic increase in yield is associated with this resistance when these cultivars are compared to susceptible wheat lines. Since aphids still occur on these cultivars, producers often ask whether it would be possible to increase yields further by applying insecticide to control the remaining aphids. Trials have shown that it is indeed possible to increase grain yields, using insecticides, but that these increases are not always economically justifiable: the combined cost of insecticide and its application are not always recovered. Factors such as Russian wheat aphid infestation level, and input cost relative to the grain market price are important profit determinants.
Afficher plus [+] Moins [-]Mots clés AGROVOC
Informations bibliographiques
Cette notice bibliographique a été fournie par International Maize and Wheat Improvement Centre
Découvrez la collection de ce fournisseur de données dans AGRIS