Stella Antony, C. C. Steel, B. Stodart, R. Billones-Baaijens, S. Savocchia
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引用次数: 0
Abstract
Dieback of fruiting spurs, stems and branches of walnut trees (Juglans regia L.), caused by Botryosphaeriaceae, is widespread in walnut orchards in Australia. Five species of Botryosphaeriaceae (Diplodia seriata, Dothiorella omnivora, Neofusicoccum macroclavatum, N. parvum, and Spencermartinsia viticola) were recovered from the Australian walnut orchards in a previous study, with D. seriata and N. parvum being the most prevalent. The present study evaluated inhibitory effects of ten fungicides on mycelium growth of those five species and on conidium germination of D. seriata and N. parvum. It investigated the preventative and curative efficacy of selected fungicides on disease incidence in glasshouse and field trials. In vitro experiments showed that nine of the fungicides reduced mycelium growth, and all ten inhibited conidium germination, but to varying extents. Tebuconazole, prochloraz manganese chloride, fluazinam, fludioxonil and pyraclostrobin were the most effective for inhibiting mycelium growth (EC50 < 0.14 µg a.i. mL-1), whereas pyraclostrobin, fluxapyroxad, fluopyram, penthiopyrad and tebuconazole were the most effective for inhibiting conidium germination (EC50 < 2.2 µg a.i. mL-1). In planta experiments with five fungicides confirmed that preventative treatments had greater efficacy than curative treatments. A field trial with four commercial fungicide formulations demonstrated that tebuconazole and tebuconazole + fluopyram provided protection of walnut trees for the longest period. The field trial also confirmed the efficacy of pyraclostrobin and the inhibitory effect of fluazinam. This study is the first in Australia to evaluate fungicides in different classes and with different modes of action for efficacy against Botryosphaeriaceae recovered from walnut orchards in Australia, and provides a wider selection of active ingredients for a fungicide rotation programme than that which is currently available to the Australian walnut industry.
期刊介绍:
Phytopathologia Mediterranea is an international journal edited by the Mediterranean Phytopathological Union. The journal’s mission is the promotion of plant health for Mediterranean crops, climate and regions, safe food production, and the transfer of new knowledge on plant diseases and their sustainable management.
The journal deals with all areas of plant pathology, including etiology, epidemiology, disease control, biochemical and physiological aspects, and utilization of molecular technologies. All types of plant pathogens are covered, including fungi, oomycetes, nematodes, protozoa, bacteria, phytoplasmas, viruses, and viroids. The journal also gives a special attention to research on mycotoxins, biological and integrated management of plant diseases, and the use of natural substances in disease and weed control. The journal focuses on pathology of Mediterranean crops grown throughout the world.
The Editorial Board of Phytopathologia Mediterranea has recently been reorganised, under two Editors-in-Chief and with an increased number of editors.