Relationship between salicylic acid and resistance to mite in strawberry

• Published in: Folia Horticulturae 2021-06, Vol.33 (1), p.107-119
• Main Authors: Vilela de Resende, Juliano T., Matos, Rafael, Zeffa, Douglas M., Constantino, Leonel Vinicius, Alves, Silas M., Ventura, Maurício U., Resende, Nathalia C. V., Youssef, Khamis
• Format: Article
• Language: English
• Subjects: Abiotic stress; Acid resistance; Acids; Agronomy; Assaying; Cell walls; Eggs; Females; Fragaria ananassa; fragaria × ananassa; Fruits; Mesophyll; Mites; morpho-anatomical; Parameters; Parenchyma; Pest resistance; Pesticides; Pests; Plant species; Salicylic acid; Strawberries; Tetranychus urticae; Thickness; Trichomes
• ISSN: 2083-5965; 0867-1761; 2083-5965
• DOI: 10.2478/fhort-2021-0008

The two-spotted spider mite (TSSM) is a polyphagous pest which infests several wild and cultivated species of plants worldwide. To date, this mite is the most deleterious pest attacking the strawberry plant under a protected environment. Exogenously applied salicylic acid (SA) has been found to induce resistance to biotic and abiotic stresses. Morpho-anatomical changes in strawberry leaflets and TSSM preference tests were investigated in response to SA treatment. Plants grown in a greenhouse were foliar sprayed with different concentrations of SA (0 mg · L , 25 mg · L , 50 mg · L , 75 mg · L and 100 mg · L ). After the third application, certain parameters including the number of glandular and non-glandular trichomes, thickness of leaflet, abaxial cell wall, adaxial cell wall, palisade and lacunous parenchyma and mesophyll were measured using scanning electronic microscopy (SEM). Two-choice and non-choice assays were employed to verify the TSSM preference. Exogenous treatment with SA promoted morpho-anatomical changes in the following parameters, namely: thickness of the leaflets, mesophyll, lacunous and palisade parenchyma, cell wall (abaxial and adaxial) and the number of glandular and non-glandular trichomes in strawberry leaflets. In general, TSSM preferred less leaflets treated with SA compared with the control in a two-choice assay. A lesser number of TSSM eggs and live females were also recorded in leaflets treated with SA compared with the control plants in no-choice assays. The values of the number of eggs and live females correlated negatively with those obtained for the morpho-anatomical traits induced by exogenous SA.