Effects of Metribuzin Herbicide on Some Morpho-Physiological Characteristics of Two Echinacea Species

Echinacea is a perennial plant that used for its phytotherapeutic potential. crops are often affected by invasive weeds. One of the most effective strategies in weed control use chemicals such as herbicides. However, herbicides also affect physiological and morphological processes Echinacea. For this reason, aim study was to determine effects different dosages (0, 250, 500, 750, 1000, 1250 g ha−1) postemergent herbicide metribuzin on some characteristics purpurea angustifolia collected from locations Iran (E. Shiraz Isfahan regions E. Ardestan Kazerun regions). Application decreased leaf dry weight both species at high doses (750 ha−1). At dose (1250 ha−1), leaves showed an increase MDA (malondialdehyde) up 9.14, while other content lower. Minimum maximum fluorescence increased registered dosage (500 (750–1250 treatments species. The Fv/Fm (maximum quantum yield) value reduced treated species, compared control, starting 250 ha−1 dose, lowest 750 dose. results indicate has adverse physiology morphology above 500 ha−1.