Response of Carrot and Lettuce Plants under Meloidogyne incognita Stress to Biochar Amended Soil

Carrot and lettuce plants are highly susceptible to Meloidogyne incognita, and exhibit reduced yield and its quality. The limitations of synthetic nematicides have prompted the search for sustainable alternatives. This study evaluated the effect of sugarcane stem and weed (Blumia aurita) derived biochar (SGC/WDBC) and mango leaf biochar (MGBC) at 1.5, 2.5, and 3.5 kg/m² on M. incognita infection as well as on the growth and yield of carrot and lettuce under field conditions. Biochars were incorporated into soil before inoculation with M. incognita (2500 juveniles/plant), and their performance was compared with Furadan and NPK fertilizer. The highest biochar rate (3.5 kg/m²) significantly reduced the galling, egg mass formation, and nematode abundance in both crops. The SGC and WDBC performed best for lettuce, while MGBC produced the most favourable effects on carrot. Biochar application enhanced vegetative growth and yield relative to unamended and fertilizer-treated plots. The trial demonstrated that locally sourced biochars can serve as an effective and eco-friendly option for managing root-knot nematodes and improving vegetable productivity.