ABSTRACT
Canola seed cake extracts for the control of Pratylenchus brachyurus

Giovane P. Notarantonio1*, Simone M. Santana-Gomes1, Beatriz C. B. Barros1, Frank W. Ferreira2, and Claudia R. Dias-Arieira1
 
The lesion nematode Pratylenchus brachyurus is a major pest of several crops. Given its wide geographic distribution and broad host range, the search for innovative strategies to manage the rising populations of these parasites has become increasingly necessary. This study aimed to evaluate the effect of different dilutions of canola (Brassica napus L.) seed cake extracts on P. brachyurus mortality, reproduction, and penetration. Nematode mortality was assessed in vitro assay using a 3 × 7 (Extraction method × Dilution factor) factorial design with four replicates and two trials. For evaluation of nematode reproduction, a greenhouse experiment was carried out using a 2 × 4 (Application method × Dilution factor) factorial design with eight replicates and two trials. Nematode penetration was evaluated in a greenhouse experiment with a 2 × 5 (Seed treatment × Evaluation period) factorial design. Canola seed cake extracts were analyzed by high-performance liquid chromatography. The maximum nematode mortality values estimated from in vitro results were 78% and 100%, achieved with 10.88% and 10.15% extract, respectively. In the reproduction experiment, both seed treatment and in-furrow application resulted in effective nematode control, reaching 76% in the first trial and over 90% in the second trial compared with the control. In the penetration test, extract treatment reduced nematode number by 53% and 56% at 20 and 25 d after inoculation, respectively, compared with the control. The major compounds identified in canola seed cake extracts were ferulic, trans-cinnamic, caffeic, coumaric, chlorogenic, and gallic acids, along with the flavonoids quercetin and kaempferol.
Keywords: Brassica, lesion nematode, nematicidal compounds, organic waste, plant extracts.
1Universidade Estadual de Maringá, Programa de Pós-Graduação em Agronomia, Maringá, Paraná, Brasil.
2Universidade Estadual de Maringá, Graduaçãoem Agronomia, Maringá, Paraná,Brasil.
*Corresponding author (giovane_notarantonio@hotmail.com).