Vegetative growth and sporulation of Bipolaris sorokiniana on infected leaves of Poa pratensis exposed to postemergence herbicides

Abstract

HODGES, C. F. 1992. Vegetative growth and sporulation of Bipolaris sorokiniana on infected leaves of Poapratensis exposed to postemergence herbicides. Can. J. Bot. 70: 568-570. Poa pratensis was exposed to the postemergence herbicides 2,4-D, MCPP, and dicamba at concentrations of M applied to the soil surface. The four youngest leaf blades were inoculated with Bipolaris sorokiniana and subsequently detached to determine the effect of the herbicides on vegetative hyphal growth and sporulation on the leaf-blade tissue. Hyphal growth from infected leaf disks cut from detached leaves was stimulated by 2,4-D and dicamba. MCPP did not affect hyphal growth. All herbicides increased sporulation by B. sorokiniana on the detached leaves. Increases in sporulation did not differ between 2,4-D and MCPP. Dicamba induced the heaviest sporulation on leaf blades. Key words: dicamba, MCPP, mecoprop, 2-methoxy-3,6-dichlorobenzoic acid, 2(2-methyl-4-chlorophenoxy)propionic acid, 2,4-dichlorophenoxyacetic acid. HODGES, C. F. 1992. Vegetative growth and sporulation of Bipolaris sorokiniana on infected leaves of Poa pratensis exposed to postemergence herbicides. Can. J. Bot. 70 : 568-570. Des plantes de Poa pratensis ont Ct C exposCs aux herbicides de post-tmergence 2,4-D, MCPP et dicamba, i des concentrations de M appliquies a la surface du sol. Les lames des quatre feuilles les plus jeunes ont ttC inocultes avec le Bipolaris sorokiniana et detachies subsCquemment pour dtterminer I'effet des herbicides sur la croissance vCgCtative des hyphes et la sporulation sur la lame foliaire. La croissance des hyphes a partir de disques foliaires infect& prClevBs sur des feuilles ditachCes, est stimulte par le 2,4-D et le dicarnba. Le MCPP n'a pas affect6 la croissance des hyphes. Tous les herbicides augmentent la sporulation par le B. sorokiniana sur feuilles dCtachCes. Les augmentations de la sporulation ne sont pas diffkrentes entre le MCPP et le 2,4-D. Le dicarnba induit la sporulation la plus forte sur lames foliaires.Mots clis : dicamba, MCPP, mCcoprop, acide 2-methoxy-3,6-dichlorobenzoique, acide 2(2-mCthyl-4-ch1orophCnoxy)propionique, acide 2,4-dichlorophCnoxyacCtique.[Traduit par la ridaction]

Arbuscular Mycorrhizal Fungi

“…Considering chemical treatments, the postemergence herbicides 2,4-D, MCPP and dicamba are shown to increase B. sorokiniana disease severity on Poa pratensis, a host plant resistant to the herbicides in the studies (Hodges, 1978(Hodges, , 1984. Different herbicides also increase the sporulation of B. sorokiniana on P. pratensis leaf tissue of all ages (Hodges, 1992(Hodges, , 1994, which could influence inoculum potential of the soil and disease severity of a following barley crop.…”

Fruit-Eating Bats and Birds of Three Seasonal Tropical Dry Forests in the Americas

“…Considering chemical treatments, the postemergence herbicides 2,4-D, MCPP and dicamba are shown to increase B. sorokiniana disease severity on Poa pratensis, a host plant resistant to the herbicides in the studies (Hodges, 1978(Hodges, , 1984. Different herbicides also increase the sporulation of B. sorokiniana on P. pratensis leaf tissue of all ages (Hodges, 1992(Hodges, , 1994, which could influence inoculum potential of the soil and disease severity of a following barley crop.…”