Standardization of ectomycorrhizal inoculation technique for apple seeds

A technique was standardized to inoculate apple seeds with ectomycorrhizal fungus to facilitate transfer of inoculated seedlings in field/pots during active growth stage to evaluate the effect of mycobiont association on growth and nutrition. Wheat grain substrate was used as mass mycobiont inoculum to carry out the experiment. Two soil types viz. soil collected from apple orchard floor and from uprooted plant basin were used for comparing efficiency of inoculation technique. Two inoculation methods viz. column and bottom layer were evaluated. Ice cream cups made up of card board were used for placing 200 ml volume of soil media. In column method, inoculum was placed in column of 3 cm height prepared with the help of cork borer (8mm dia.), while in bottom layer method, inoculum was placed in middle of soil layers. Stratified apple seeds were placed over each column or layer in such a way that germinating radicle passes through the inoculum source. Twenty days old seedlings along with intact soil bowl from the cup were transplanted in pots. Observations on mycorrhiza establishment and growth attributes were recorded at regular intervals. Both the methods were equally efficient for the establishment of mycorrhiza, however, column method exhibited better distribution of infected roots than bottom layer method. The inoculation of mycorrhiza has been found to attribute higher growth rate in apple seedlings w.r.t shoot height, dry weight, collar diameter and root volume than non-inoculated check. The technique is easy, simple, economical, reliable and desired inoculum could be regulated for seedlings of different ages.