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IVES 9 IVES Conference Series 9 Selection of beneficial endophytes from Sicilian grapevine germplasm 

Selection of beneficial endophytes from Sicilian grapevine germplasm 

Abstract

The recent expansion of arid areas due to climate change is putting grapevine and the other traditional productions at risk in all Mediterranean countries with a limited availability of fundamental resources such as water. It is possible to improve the resilience of vineyards by developing sustainable agricultural practices based on biological and natural resources such as endophytic microorganisms that colonize inner plant tissues, and which can potentially increase the tolerance to abiotic stresses. A selection of grapevine endophytes was conducted from 2021 to 2023 as part of the PRIMA project PROSIT. In particular, the research aimed to select consortia of endophytic bacteria and/or fungi able to improve the grapevine tolerance to drought. To this aim, vine leaves were harvested during two vegetative seasons, from local varieties subjected to a long-lasting adaptation to arid conditions without regular irrigation. A wide diversity of genera and species belonging to different microbial phyla was isolated on artificial media (NA and PDA) from surface-sterilized grapevine leaves. Selected fungal and bacterial isolates were identified by molecular barcoding based on ITS and 16S rDNA sequences, respectively. Overall, bacterial endophytes were isolated in higher numbers than fungal ones. In 2022, a higher abundance of fungal colonies was isolated at the end of the growing season, suggesting a seasonal dynamic of the microbiota composition. Some of the selected isolates belong to species already known as PGP endophytes of crops, including grapevine. Preliminary in vitro experiments confirmed that those strains can increase the concentration of auxins, ammonium and soluble phosphate.

DOI:

Publication date: June 13, 2024

Issue: Open GPB 2024

Type: Poster

Authors

Dalila Crucitti1*, Irene Doro2, Michela Zottini2, Alessandra Tondello3, Andrea Squartini3, Roberto De Michele1, Francesco Carimi1, Davide Pacifico1

1 IBBR CNR – Institute of Biosciences and Bioresources, via Ugo La Malfa 153, 90146 Palermo
2 Department of Biology, Università degli Studi di Padova, via U. Bassi 58b, 35131 Padova, Italy
3 Department of Agronomy, Animals, Food, Natural Resources, and Environment, DAFNAE Università degli Studi di Padova, Viale dell’Università 16, 35020 Legnaro (PD), Italy

Contact the author*

Keywords

drought stress, culturable endophytes, bacteria, fungi

Tags

IVES Conference Series | Open GPB | Open GPB 2024

Citation

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