author(s)
GN Grace, TN Shivananda, MS Rao and R Umamaheswari

abstract
Plant parasitic nematodes are important biotic restrictions in the horticultural systems. Root-knot nematode, Meloidogyne incognita is a major economic pest in various crops. Wide usage of pesticides against parasitic nematode causes health hazards; hence there is an urgent need for an alternative. Biocontrol agents serve as an alternative. P. lilacinum is a nematophagous fungus which is used as a biocontrol agent. Tuberose (Polianthes tuberosa L.) is an important ornamental crop in India and it has great economical value as a cut flower and in the perfume industry. Root knot nematodes cause serious damage to roots of tuberose, resulting in 14-15% yield loss. Keeping this in view, the present studies were under taken to evaluate the efficacy of liquid formulation of P. lilacinum in tuberose. The experiments were conducted during 2015-2016 in both greenhouse and field conditions. Six treatments were used in this study. In greenhouse conditions, corms treated along with soil application of 2 tons/ha of vermicompost enriched with 5 l of P. lilacinum have showed a maximum increase in the plant growth parameters like spike length (71.25 cm), spike weight (44.34 g), root length (15.38 cm), root weight (7.18 g) and reduced nematode gall index (1.5). Field assessment confirmed significant inhibition of nematode reproduction, inhibition of root galling and an increase of tuberose yield compared with the control.