Antinemic Metabolites of Simarouba glauca against Root Knot Nematode, Meloidogyne incognita Infesting Groundnut, Arachis hypogaea

Background: Groundnut, Arachis hypogaea is a leguminous crop grown in tropical and subtropical regions of the world. Meloidogyne spp., is considered to be nematode pest of economic importance for the groundnut throughout the world. Plant metabolites with nematicidal property have been in use for a long time for nematode control that offer many environmental advantages. Methods: The nematicidal activity of methanolic leaf extract of Simarouba glauca on eggs and juveniles (Js) of root-knot nematode, Meloidogyne incognita infesting vegetables was evaluated at three concentrations in vitro (100%, 50%, 25%) with control at three exposure times. Result: Results revealed that at 100% concentration, the methanolic leaf extract of S. glauca showed the least number of eggs hatched (7.85, 12.63, 16.30/egg mass) and the highest mortality (60.58, 70.23, 92.58/100 juveniles) at the exposure times of 24 hrs, 48 hrs, 72 hrs, respectively. The phytochemical compounds viz., Hexadecanoic acid-methyl ester, Isopropyl palmitate, Octadecanoic acid and Methyl stearate detected through GC-MS profiling of methanolic extract of S. glauca were found to inhibit the nematode activity. Pot and field studies proved that soil application of Simarouba leaf powder @ 10 g/plant and 5 kg/ha reduced the nematode infestation. This study implies that use of Simarouba leaf powder produces nematicidal effect against plant parasitic nematodes and reduced the nematode infestation in groundnut and is more suitable candidate in the context of biological control.