Wheat and triticale root development as affected by trifluralin

A growth chamber study was conducted to investigate the effects of trifluralin on root morphology of wheat and triticale seedlings. Five spring wheat cultivars, five durum wheat cultivars and three triticale cultivars were grown for 15 days in soil treated with 0, 0.4 and 0.8 ppm trifluralin. Root damage from trifluralin in both wheat and triticale was greater at 0.8 ppm than 0.4 ppm. The 0.4 ppm rate of trifluralin reduced dry weight of Canuck, Hercules and Carman compared to the control; however, at 0.8 ppm, root dry weight of all cultivars was reduced compared to the control. Trifluralin injury symptoms included increased number of seminal roots, decreased seminal root extension, increased root diameter, and reduced root dry weight. As a group, the roots of spring wheat were injured more by trifluralin than the roots of either durum wheat or triticale. Differences in root damage amongst the cultivars was more apparent after the appearance of the second radicle root. A negative correlation was obtained between caryopsis lipid content (μg lipid per caryopsis) and root dry weight among the cultivars at the 0.8 ppm trifluralin rate.Key words: Trifluralin, wheat, triticale, root morphology, lipid