Influence of organic growing media in combination with microbial bio-agents (Clonotri or Sublic) on the growth parameters of olive (Olea europaea L.) plantlets in the nursery

Abstract

In addition to their well-known use for soil amendment, an increasingly popular use of composts is a constituent in container media. The two main reasons of this popularity are: I) in many cases non-edible crops such as ornamentals, forest, garden trees and shrubs etc. can serve as a safe outlet for composts that may be considered as non-desirable for food crop production, II) various composts act equally well as peat moss in growing media, while their cost is considerably lower. The fact that mature composts are also suppressive to several soil-borne pathogens, of which peat is conducive and has encouraged many growers to substitute part or all of the peat with such composts. Typical examples for the use of composts in container media include transplant production, substrates for pot plants, forest and fruit tree saplings and substrates for greenhouse-grown plants, especially ornamentals but in some cases also edible crops. (Raviv, 2008). ABSTRACT Composting and the use of compost products in horticulture and agriculture have been researched widely. In this study three growing media were investigated. Growing media were treated or not with either fungal commercial formula “Clonotri” based on (Trichoderma harzianum Fv178, Clonostachys rosea Fv114) or bacterial commercial formula “Sublic” based on (Bacillus licheniformis and B. subtilis). The effects of the different growing media (organic MAIB, organic MAIB-ECOS, conventional MAIB), alone or in combination with biocontrol agents (Clonotri or Sublic), on vegetative parameters (plant height, plant weight and root weight) of olive plantlets (CV, Leccino) inoculated or not with Verticillium dahlia, were evaluated. Olive plantlets grown in the un-inoculated media showed a significant increase in all vegetative parameters. The two organic growing media increased significantly all vegetative parameters, in which the higher effect was obtained using the organic MAIBECOS in combination with the two microbial bio-agents.