Effect of haloxyfop and alloxydim applied separately and in combination with salicylic acid, diphenylamine, or norflurazon on the root growth and fatty acid composition of the selected species of grasses and dicotyledonous plants

Eight species from the grass family were studied: wheat, rye, triticale, barley, oats, maize, couch grass, rice, and two dicotyledonous species: field pea and common flax. Seedlings of the tested species were grown in hydroponic cultures with haloxyfop or alloxydim alone (graminicides) and with haloxyfop or alloxydim plus one of the tested antagonists (diphenylamine, salicylic acid, or norflurazon). All investigated species of the grass family showed similar susceptibility to the tested graminicides (measured with their effect on root growth). The tested dicotyledonous species were completely unsusceptible. Except in maize, the addition of antagonistic substances to the medium with herbicide weakened considerably the inhibitory effect of both haloxyfop and alloxydim. The tested graminicides also had a significant effect on the fatty acid composition of susceptible species (except maize, where the effect was low). In the lipids of the apical parts of roots, a significant decrease in the content of oleic and linoleic acids and a considerable increase in the content of linolenic acid were observed.