Estresse salino em sementes de abóbora condicionadas com ácido salicílico

Abstract

Salicylic acid is a phenolic hormone active in the physiological and biochemical processes of plants and in resistance to biotic and abiotic stresses, such as saline. Thus, the objective was to evaluate the conditioning of hybrid and creole pumpkin seeds with salicylic acid, in order to mitigate saline stress in germination and initial development. The experiment was conducted at the Federal Institute of Piauí - Campus Uruçuí. A completely randomized design was used, in a 4 x 4 factorial scheme, using phytohormone doses (100, 150 and 200 mg L-1 and distilled water) and salinity levels (0, 2, 4 and 6 dS. m-1 ), with four replications. Two genotypes were used: hybrid cv. Atlas (American Butternut type) and a cv. Creole (milk pumpkin type). The seeds were conditioned with salicylic acid for 8 hours and then dried to initial moisture content. Then, the seeds were placed in germitest paper, the latter soaked in saline solution, in a germination chamber. The first germination count, percentage of germination and abnormal seedlings, emergence in sand, emergence speed index, length of shoot and root, and dry mass of shoot and root were evaluated. Salt stress compromises seed germination and seedling development, with the hybrid being more sensitive than cv. Creole. Conditioning pumpkin seeds with salicylic acid is not satisfactory to mitigate saline stress during germination and initial seedling development of pumpkin