In Vitro Evaluation of Nematicidal Potential and Phytochemical Profile of Four Piper Species against Root-Knot Nematode (Meloidogyne incognita)

Abstrak

Meloidogyne incognita, one of the plant-parasitic nematodes, causes significant yield losses in various cultivated plants. Dependence on chemical nematicides encourages the development of plant-based alternatives that are more sustainable. This study evaluated the nematicidal activity and phytochemical profile of extracts from the leaves of 4 Piper species (P. aduncum, P. betle, P. nigrum, and P. retrofractum) against egg hatching and second-stage juvenile (J2) mortality of M. incognita, and determined their median lethal concentrations (LC₅₀). A completely randomized design was used with 6 extract concentrations (0, 2, 4, 6, 8, and 10 ml l-¹) and 5 replications. Gas chromatography–mass spectrometry (GC–MS) analysis showed distinct phytochemical profiles: P. aduncum was dominated by dillapiole (62.30%), P. betle and P. nigrum by phenolic compounds (62.70% and 24.44%, respectively), and P. retrofractum by fatty acids (17.97%). A significant interaction between species and extract concentration affected egg-hatching inhibition and J2 mortality. At 10 ml l-¹, P. betle and P. aduncum inhibited egg hatching by 95.20% and 92.40% and caused J2 mortality of 97.60% and 95.20%, respectively. At 120 hours, the LC₅₀ values were 2.27 ml l-¹ for P. betle and 2.61 ml l-¹ for P. aduncum, compared with 2.83 and 3.00 ml l-¹ for P. nigrum and P. retrofractum, respectively. These results identify P. betle and P. aduncum as the most active extracts under the tested in vitro conditions and support their prioritization for further validation.

Kata kunci

• pest
• disease-plant sciences
• plant protection
• biological activity
• leaf extract
• phytochemicals
• plant-parasitic nematodes
• toxicity