MYCORRHIZAL INOCULATION OF CASTANEA SATIVA MILL. MICROPROPAGATED PLANTS: EFFECT OF MYCORRHIZATION ON GROWTH

Frank (1894) demonstrated for the first time that forestry plants are dependent on mycorrhizae. Several tree species can not develop without mycorrhizas. Micropropagated plants of Castanea sativa were inoculated with the mycorrhizal fungus Pisolithus tinctorius. The mycorrhizal process was monitored at regular time periods in order to evaluate mycorrhiza formation (the mantle and Hartig net) and the growth rates of mycorrhizal and nonmycorrhizal plants in terms of heights, stem diameter at the collar level, the length of the major root and the total plant length. Fresh and dry weights, as well as growth rates per unit of time (Δx/Δt) and relative growth rates (RGR) were also determined. Mycorrhizal micropropagated plants showed higher growth rates in terms of height, stem diameter at the collar level and fresh and dry weights than nonmycorrhizal ones. The length of the major root was lower in mycorrhizal plants. RGR in heights, stem diameter and fresh and dry weights were higher in mycorrhizal micropropagated plants, but the major differences could be found for stem diameter at the collar level.