Susceptibility and resistance of lavender and lavandin cultivars to four root-knot nematode species

Lavender, Lavandula spp. L. (Lamiales: Lamiaceae) is an important medicinal and aromatic plant due to its bioactive compounds. Its tolerance to arid, low productivity soils has expanded cultivation in our country, increasing plant protection issues. Root-knot nematodes, Meloidogyne spp. Göldi, 1887 (Tylenchida: Meloidogynidae) significantly reduce yield and quality and may alter active compounds, yet their control in lavender remains difficult and understudied. This study evaluated the susceptibility and resistance of lavender cultivars to four common root-knot nematode isolates: Meloidogyne incognita (Kofoid & White, 1919) Chitwood, 1949, Meloidogyne javanica (Treub, 1885) Chitwood, 1949, Meloidogyne hapla Chitwood, 1949 and Meloidogyne arenaria (Neal, 1889) Chitwood, 1949 (Tylenchida: Meloidogynidae). The study was carried out between April and June 2025 at the Nematology Laboratory of the Faculty of Agriculture, Çanakkale Onsekiz Mart University, Türkiye. Four Lavandin cultivars (Silver, Grosso, Super A and Abrialis) and six Lavender cultivars (Sevtopolis, Hemus, Raya, Drujba, Yubileina and Hebar) were tested. Grosso, Abrialis, Silver, and Drujba were resistant to all nematode isolates, while Sevtopolis was resistant only to M. javanica. In contrast, Super A, Raya, Hemus, Yubileina, and Hebar were susceptible to all isolates, and Sevtopolis was susceptible to M. incognita, M. hapla, and M. arenaria. These findings provide valuable insights for managing root-knot nematodes and promoting sustainable lavender cultivation.