Non-target effect of two fungicides on Glomus mosseae colonization of chilli roots

摘要

As fungicides either inhibit or kill fungi, they are expected to influence the population and root colonization by Arbuscular Mycorrhizae (AM) fungi. Since AM benefit plants variously by enhancing their nutrient and water status and/or increasing rootresistance to soil-borne pathogens, such benefits may be reduced if the AM colonization is hampered. Detrimental effects of several fungicides on AM fungi have been reported previously (Meng, 1982; Kough et al., 1987; Dodd and Jeffries, 1989; Kjoller and Rosendahl, 2000; Chiocchio et al., 2000).The activities of Alkaline Phosphatase (ALP) (Thingstrup and Rosendahl, 1994; Kjoller and Rosendahl, 2000), and Succinate Dehydrogenase (SDH) (Kough et al., 1987; Kling and Jakobsen, 1997) in both the external and internal fungal hyphae have been used as criteria for rapid assessment of the effect of fungicides. These enzymes are important because they indicate active fungal metabolism. SDH, a mitochondrial enzyme, is considered an indicator of viability of mycorrhiza (Vierheilig & Ocampo, 1989, Guillemin et al., 1995) while ALP activity, located within the phosphate-accumulating vacuoles of AM hyphae (Gianinazziet al., 1979), has been proposed as a physiological marker for analyzing its efficiency (Tisserantet al., 1993).