Distribution of Root-Knot Nematode (Meloidogyne incognita) in Tuberose (Polianthes tuberosa L.) Bulbs and Comparison of Extraction Methods

Root-knot nematode, Meloidogyne incognita invades, infects and survives in tuberose (Polianthes tuberosa L.) bulbs. Detection and estimation of nematode infection in tuberose bulbs is vital to nematode management. Comparison of maceration (either in water or MgSO₄.7H₂O solution), with centrifugal floatation, sieving or flocculation floatation showed better recovery of nematodes with maceration in MgSO₄.7H₂O solution. Maximum numbers of eggs, J2, J3, J4, males and females were recovered with maceration centrifugal floatation technique where maceration was done in solution of specific gravity 1.2. Most of the nematodes (58.35%) were present up to a depth of 5.2 mm, in tuberose bulbs. No nematodes were observed at a depth of > 13.0 mm.