Evaluation of the nematicidal effect of Smoke Water against Meloidogyne javanica and Aphelenchus avenae in vitro

Smoke water (SW), a liquid by-product of wood pruning waste pyrogasification, was investigated for its nematicidal potential. We evaluated SW’s efficacy against adult Aphelenchus avenae and the egg and second-stage juveniles (J2) of the root-knot nematode Meloidogyne javanica under controlled laboratory conditions. Five concentrations (100 mL/L, 10 mL/L, 1 mL/L, 0.1 mL/L) and a sterile water control were tested over four days. Undiluted SW caused complete apparent mortality of M. javanica j2 within 24 h, while 100 mL/L achieved full mortality by day 2. The 10 mL/L treatment also showed significant activity, exceeding 50% mortality by day 4. Similar responses were observed in A. avenae, with undiluted and 100 mL/L SW reaching full mortality within 1 and 4 days, respectively. Egg hatching of M. javanica was completely inhibited at undiluted and 100 mL/L SW and markedly reduced at 10 mL/L. These findings indicate that SW may represent a promising natural alternative to synthetic nematicides.