Abstract
Persimmon (Diospyros spp.) is susceptible to attack by several plant pathogens. Samples from persimmon trees displaying both leaf lesions and dieback symptoms were collected from orchards in NSW. Diseased leaves exhibited black lesions starting at the tip of the leaf, whereas dieback-infected stems showed internal staining of vascular tissues. Fungal isolation, pathogenicity, and cross-inoculation between isolates derived from different plant materials, along with preliminary evaluation of several fungicides in vitro, were tested. A single isolate of Neofusicoccum parvum and Neopestalotiopsis spp. were used as representative isolates from symptomatic samples. The leaf isolate N. parvum 004-1b, and dieback isolate Neopestalotiopsis spp. 014-1a were identified using morpho-cultural methods and PCR assay using the internal transcribed spacer region. Pathogenicity of N. parvum 014-1a was confirmed on leaves of Jiro and Fuyu cultivars. Neopestalotiopsis spp. 004-1b was cross-inoculated to leaves and confirmed to be infective. Both pathogens were re-isolated from the inoculated areas. Recommended rates (RR) and ½ RR of tebuconazole + fluopyram (0.75 ml L-1 PDA and 0.38 ml L-1 PDA), fluazinam (1.00 ml L-1 PDA and 0.50 ml L-1 PDA), and fludioxonil (0.75 mg L-1 PDA and 1.50 mg L-1 PDA) amended in PDA plates exhibited 100% growth inhibition in both isolates regardless of the concentration. In pyraclostrobin, 100% growth inhibition was only observed for Neopestalotiosis spp. 004-1b while only 87.46% growth inhibition in N. parvum 014-1a. Isopyrazam (0.75 ml L-1 PDA and 0.38 ml L-1 PDA) and penthiopyrad (1.50 ml L-1 PDA and 0.75 ml L-1 PDA) also showed potential in inhibiting the growth of both isolates relative to the control plate. To our knowledge, this is the first report of Neofusicoccum parvum as a persimmon leaf pathogen and the cross-infectivity potential of Neopestalotiopsis spp. to persimmon leaves. Results from preliminary evaluation of different fungicides warrant further studies in glasshouse assays.
| Original language | English |
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| Number of pages | 1 |
| Publication status | Published - 22 Nov 2023 |
| Event | 24th Australasian Plant Pathology Society Conference 2023: APPS 2023 - National Wine Centre, Adelaide, Australia Duration: 20 Nov 2023 → 24 Nov 2023 https://eventstudio.eventsair.com/apps2023/ https://www.appsnet.org/publications/proceedings/APPS%202023%20Abstracts.pdf (Abstract book) https://az659834.vo.msecnd.net/eventsairaueprod/production-eventstudio-public/c4b675474ade410cad22646e6cd307d6 (Conference program) |
Conference
| Conference | 24th Australasian Plant Pathology Society Conference 2023 |
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| Abbreviated title | Change and adaptation |
| Country/Territory | Australia |
| City | Adelaide |
| Period | 20/11/23 → 24/11/23 |
| Other | On behalf of the organising and scientific committees we are pleased to announce the 2023 Australasian Plant Pathology Society Conference. The conference will be held in Adelaide, South Australia, 20 - 24 November at the National Wine Centre, corner of Botanic & Hackney Roads, Adelaide, South Australia. For those unable to attend face-to-face a virtual platform housing pre-recorded presentations, poster galley and virtual exhibition will be accessible to all delegates post event for 3 months. The theme for the conference, “Change and Adaptation”, has been chosen to highlight the ever-changing nature of pathogens and the array of emerging technologies being developed to monitor and control disease. Please join us to stay connected with colleagues, support our emerging scientists, and showcase and access the most recent plant pathology research, either online or in the relaxed and beautiful environment of Adelaide and its parklands. |
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