Fungal organisms constituting sooty mould on cool-stored ‘Zesy002’ and ‘Hayward’ kiwifruit in New Zealand

Sooty mould describes the complex of superficial, Ascomycota fungi that grow upon the honeydew exudates from different Hemiptera species.
Kiwifruit affected by sooty mould were harvested from a commercial orchard in June 2021 and cool-stored for six months at 1°C. Fungal communities were isolated from the lenticels, skin and flesh of ‘Zesy002’ and ‘Hayward’ kiwifruit at three time periods: 0-, 3- and 6-months postharvest.
Fruit tissue samples were grown on potato dextrose agar (PDA), morphotyped and identified to genus level using DNA sequencing.
A total of 1862 fungal isolates were obtained from 450 ‘Zesy002’ and 450 ‘Hayward’ tissue samples.
Forty-two different fungal morphotypes, belonging to 17 different genera were identified, with Cladosporium spp. being the most commonly isolated taxa from both ‘Zesy002’ and ‘Hayward’ fruit (23.3 and 40.9% of isolates, respectively). Differences occurred between cultivars, for example, Alternaria spp. was relatively common on ‘Zesy002’ but not on ‘Hayward’. Additionally, the community composition of sooty mould changed as time increased in cool storage.
This research will inform the development sustainable control strategies to reduce insect honeydew excretions.

XXXI International Horticultural Congress (IHC2022): International Symposium on Sustainable Control of Pests and Diseases

S.-L. Blackwood, S.G. Casonato, E.E. Jones, M. Walter, D. Logan

Actinidia chinensis var. chinensis, Actinidia chinensis var. deliciosa, Cladosporium spp., postharvest, cool storage, sustainability, Scolypopa australis

https://doi.org/10.17660/ActaHortic.2023.1378.47