The Influence of Ericoid Endomycorrhizae and Mineral Nutrition on the Growth of Micropropagated Plants of Vaccinium corymbosum L.

In vitro propagation is widely recognized as an excellent way to produce a lot of plants in a short time. Micropropagated plants show a better field performance than those obtained by traditional cuttings: bushier growth habit, increased vigour and number of branches and flowering buds, and higher early yields. As the wild highbush blueberries have symbiotic relationship with endomycorrhizae of Ascomycetes such as those of the genus Hymenoscyphus and Oidiodendron, previous studies on the best mycorrhization procedure and on the effect of inoculation of selected mycorrhizal fungi combined with fertilization on rooting and growth of micropropagated plants of Vaccinium corymbosum were carried out on 9 blueberry cvs with 11 types of mycorrhizae. A remarkable interaction between the fungus strain and the blueberry cultivar were found both on the growth and habit of plants and on root development. The effect of mineral nutrition depended both on blueberry cultivar and on mycorrhizal strain. In the present research, the results of four years of cultivation in the soil of the same plants are reported. The effect of the interaction between cultivar and fungus strain is still remarkable on the size of plants, on the number and length of shoots, and also on the number and length of basal suckers. As for nutrition, the trials confirm the positive role of P on the growth of plants, and the multiple interaction between cultivar, fungus and fertilizer.