Efficacy of Metarhizium anisopliae and Purpureocillium lilacinum isolates in the control of Meloidogyne incognita race 3 in cotton

Abstract

Plant-parasitic nematodes such as Meloidogyne incognita cause severe damage to the cotton root system, impairing plant development and yield. The use of fungi-based nematicides presents a sustainable and promising alternative for nematode management. Two greenhouse experiments were conducted to evaluate the efficacy of isolates of the Metarhizium anisopliae and Purpureocillium lilacinum entomopathogenic fungi in controlling M. incognita, in TMG91WS3 cotton cultivar. The experiment 1 included 12 treatments: one inoculated control, four M. anisopliae isolates and seven P. lilacinum isolates, with four replicates. At 162 days after sowing, all treatments significantly reduced the final population of M. incognita, except M. anisopliae IBCB Ma03. The P. lilacinum IBCB Pl06 and M. anisopliae IBCB Ma04 isolates were the most effective, with reproduction factors below 1 and efficiency close to 80 %. The experiment 2 included 11 treatments: one control, four M. anisopliae and six P. lilacinum isolates, with six replicates. After 97 days, only the IBCB Pl06 isolate differed from the control in the final population variable, although all tested isolates, except M. anisopliae IBCB Ma03, showed positive efficacy for the P. lilacinum (> 90 %) and M. anisopliae IBCB Ma04 (85 %) isolates.

KEYWORDS: Gossypium hirsutum, root-knot nematode, entomopathogenic fungi.