Abstract:
Three pot experiments were carried out at the nursery site of Research Station,
Department of Export Agriculture, Matale. Growth response of black pepper (Piper
nigrum Linn.) cuttings (cultivar GK49) at different levels (25g, 75g, 150g, 300g, Og) of
Vesicular Arbuscular Mycorrhizal (VAM) inoculum (containing VAM spores and
structures with host crop roots and moist soil) were tested, with the objective of finding
the most effective spore density. In order to find out the inoculating ability of native
VAM inoculum, two pepper cultivars ( Panniyur-1 and MB 12) were also tested with
native VAM spore isolates and exotic VAM ( Glomus mosseae) in a factorial
combination. Three types of native VAM spor e isolates were compared with the exotic
VAM to investigate regeneration ability in Sorghum bicolor as a micro-pot experiment.
Darkly stained VAM fungal hyphae and other structures in black pepper roots
confirmed the success of inoculation. Improvement in root length and plant growth
suggests that 300g inoculum (spore density of 3.5 spores/ lg potting mixture) can be
recommended to inoculate pepper cuttings at the nursery. Continuation of observations
for 6 months period would be appropriate to obtain better recommendation on effective
spore density requirements of inoculum for pepper rooted cuttings.
Observations of pepper growth improvements suggest that the native VAM inoculum
could be used as a suitable alternative for exotic VAM inoculum. The highest
performance was observed in native VAM inoculated black pepper cultivar Panniyur-1.
According to the results of micro-pot experiment, Hatamunagala isolates (a native
spore isolate) found to be superior to other VAM spore isolates. Morphological
variations in fungal structures indicated the possible existence of a mixture of fungal
species in initial native isolates that were tested. Formal identification of different
VAM fungi species available in native isolates would be beneficial.
