S13 - Session P1 - Properties of organic compost from vineyard pruning residues and wine lees and evaluation when used as soil improver for grapevine saplings under various irrigation treatments

Authors: Eleni Lampraki, Pinelopi Baltzoi *, Ioannis Tsirogiannis, Georgios Patakioutas, Nikolaos Mantzos, Dimitrios Kyrkas, Georgios Gizas

Wineries and grapevine cultivation produce large quantities of organic wastes which through composting could be converted to organic soil improver. The present study aimed to assess the effect of a mixture of peat and perlite 1:1 with 10% organic compost (vineyard pruning residues and wine lees) in two initial C:N ratios, 30:1 and 10:1, for grapevine saplings. The composting process of vineyard pruning residues and wine lees lasted 75 days in rotting boxes with self-aeration while urea was added for achieving the two initial C:N ratios. The experiment was carried out in a greenhouse in a completely randomized design with 3 replications and 9 treatments (including a control one, where no compost was used) within 60 days. Treatments included the mixtures of peat and perlite 1:1 with 10% organic compost with two initial ratios: a) C:N 30:1 with treated and untreated wine lees and b) C:N 10:1 with wine lees treated and untreated. Irrigation was applied up to 66% and 100% of the available substrate moisture. The main chemical characteristics of organic compost were measured both during the composting process and at the end. Physical properties of the final mixtures were also determined. Plant growth parameters, yield and root dry matter, leaves and roots nutrients, leaf area and plant chlorophyll content were measured. Folin determination for estimation of total phenolic content in plant tissues and proline determination for plant abiotic stress tolerance were carried out. The results showed significant increases in the measured plant growth parameters of all compost treatments relative to control treatment. Among compost treatments, those with initial ratio C:N 30:1 appears to result the largest plant growth. Vineyard pruning residues can be used for compost production along with wine lees and promote grapevine saplings growth under greenhouse conditions.