Annals of Botany 81: 385-389, 1998
© 1998 Annals of Botany Company
Chlorsulfuron Reduces Extension of Wheat Root Tips in Low-zinc Solution Culture
Department of Plant Science, University of Adelaide, PMB 1, Glen Osmond, SA, 5064, Australia Department of Soil Science and Plant Nutrition, University of Western Australia, Nedlands, WA, 6907, Australia
February 17, 1997 ; September 26, 1997 . November 4, 1997 .
Root tip extension was used as a measure of wheat root response to exposure to the sulfonylurea herbicide chlorsulfuron. Plants pre-grown in low-zinc (0.2 µMZnHEDTA) solutions were placed in a perspex chamber with nutrient solution on both sides of a partition separating the root tip from the rest of the plant. The root tip was exposed to different concentrations of chlorsulfuron and observations were made during 22 h. Increasing the concentration of zinc in the solution around the root tip to 4 µMZnHEDTA did not alter root tip extension in the absence of chlorsulfuron. Significant decreases in root growth after 22 h were obtained with concentrations of 120 µg chlorsulfuron l-1and greater. Increasing the Zn concentration from 0.2 to 20 µMZnHEDTA in the nutrient solution around the root tip decreased control root growth but stimulated chlorsulfuron-treated roots to extend at the same rate as chlorsulfuron-free control plants. Adding Zn and chlorsulfuron to the more mature root parts above the root tip partition did not significantly influence root tip extension. It is concluded that chlorsulfuron inhibits wheat root growth and that increased Zn concentrations can alleviate or prevent the deleterious effects of chlorsulfuron.Copyright 1998 Annals of Botany Company
Wheat,Triticum aestivumL., chlorsulfuron, root growth, zinc.