Seed priming with salicylic acid enhances growth, physiological traits, fruit yield, and quality parameters of cantaloupe under water-deficit stress

Abstract

Cantaloupe is a nutritive and popular commercial fruit crop. Soil moisture deficit could seriously jeopardize the yield and quality of cantaloupe. Salicylic acid (SA) has a proven role in sustainably mitigating environmental stresses in many plants applied through various methods. A factorial experiment consisting of six SA seed priming doses (non-primed control, 100, 200, 300, 400, and 500 ppm) and three soil moisture regimes (50%, 75%, and 100% field capacity [FC]) was conducted to evaluate the performance of cantaloupe in terms of growth, physiological traits, fruit yield, and quality parameters. The results revealed that severe moisture-deficit condition of 50% FC drastically reduced fruit yield (64%), water productivity (48%), total soluble solids (22%), and membrane stability index (43%), while electrolyte leakage was increased by 260% at the same soil moisture regime compared with 100% FC without any SA application. Plants grown from SA primed seeds exhibited significantly better performance in terms of seed germination traits, growth, physiological, and fruit yield parameters than non-primed plants across soil moister regimes. The performance of cantaloupe in terms of germination rate, root and shoot dry matter, fruit yield, water productivity, total soluble solids content, and membrane stability index was better at 300 ppm SA priming dose, which was statistically similar with 400 and 500 ppm SA doses in most cases. A consistent trend of better performance at 300 ppm SA dose, especially at severe soil moisture-deficit of 50% FC, was observed (48%, 59%, 54%, and 153% higher fruit yield, water productivity, membrane stability index, and net photosynthetic rate, respectively, compared with the non-primed control at the same soil moisture regime). There was almost no effect of increasing SA priming dose above 300 ppm; therefore, this could be regarded as an optimum dose for maximizing productivity and economic returns when cantaloupe is grown under soil moisture-deficit conditions.