Eureka! Institutional Repository

ABSTRACT This diploma thesis explored the development of herbs (aromatic plants), namely lemon balm (Melissa officinalis) and medicinal salvia (Salvia officinalis) in different biomaterials, in order to assess their agronomic characteristics. The three biomaterials used, were digested manure, derived from the recovery and treatment of waste from a biogas plant, a compost produced by the treatment of plant crop residues (biocompost) and finally a compost containing the fungus Trichoderma harzianum, which grows at the roots of some plants and from this symbiosis benefit both the plant and the fungus. The organ resulting from the union of the rhizome with this beneficial microorganism is called mycorrhiza. The substrate used was the commercial mixture of peat and perlite, which was combined with the three materials. The goal of this experiment is to evaluate all three of these materials as soil additives (improvers). The soil treatments of the substrate combinations with each compost (improver) were expressed in four proportions. In one of these (treatments), there was the substrate alone, which was called our control. In the other three, the substrate was combined with the three materials in different proportions: 1:2 (substrate : compost), 1:10 (substrate : compost) and 10:1 (substrate : compost). The plant seeds were supplied by ELGO (Greek (Hellenic) Agricultural Organization) DIMITRA. The experiment was conducted in two places. In the greenhouse, located on the farm of ATEI Thessaloniki, where the sowing (planting), transplantation and successive (reiterative) measurements of plant growth characteristics took place and in the industrial laboratory of the Department of Food Technology, where the soil analyses were carried out. The growth characteristics measured were chlorophyll, the number of nodes – branches and the height of the plants. The soil analyses calculated the following: the percentage (quota) of total nitrogen, the percentage of moisture and organic matter and mg/L of phosphorus. In salvia, the germination results were not satisfactory. Three plants germinated and were grown in total, two in the 1:2 and 1:10 ratios of biocompost and one in 10:1 of (digested) manure. In lemon balm, biocompost generally favoured seed germination more than the other soil additives, while the other two composts had a bad effect on seed germination, with worse effects on mycorrhiza. In terms of plant germination capacity, the best treatments were 1:2 and 10:1 – substrate : biocompost (8 grown plants of lemon balm for each one of them). As regards the plant growth characteristics, these were assessed two times. The results of the statistical analysis, such as the significant differences between biomaterials and soil treatments, in terms of growth characteristics, were various for each evaluation. The diagrams of the means, relating to the final (2nd) evaluation, show the following: 1. Treatment 1:2 – substrate : biocompost, stimulates more than any other the synthesis of chlorophyll, as the plants of this treatment showed the highest values, while the treatment of 1:2 – substrate : manure (digested) had a negative effect on the composition of chlorophyll, since its values in these plants were the lowest. 2. Treatments 1:2 – substrate : mycorrhiza, 1:10 - substrate : biocompost, 1:10 – substrate : (digested) manure and the control, stimulate the greatest branching, as in these plants, the number of nodes was the highest, while the treatments 1:2 – substrate : (digested) manure and 10:1 – substrate : biocompost, had the most adverse effect on the branching of plants. 3. Treatments 10:1 – substrate : (digested) manure and the control favoured more than any other plant height, while again 1:2 - substrate : (digested) manure and 10:1 – substrate : biocompost had the worst effect, in terms of this characteristic, since the plants of the last treatments were the lowest.