https://doi.org/10.37229/fsa.fjh.2026.05.17

The study findings demonstrated that foliar application of salicylic acid and chitosan resulted in tremendous changes in vegetative growth characteristics, yield characteristics, and chemical characteristics of potato plants (Solanum Tuberum L.) cv. Hermes. These gains were realized either in cases of administration of each treatment separately or in combination of both. Salicylic acid, particularly at a concentration of 100 mg L⁻¹, enhanced growth indices, increased productivity, and improved the nutritional composition of tubers in terms of mineral elements, nitrogen, and protein content. This effect is attributed to its role in stimulating physiological processes, enhancing photosynthetic efficiency, and improving the translocation of photosynthates toward storage organs. In contrast, chitosan exhibited a concentration-dependent stimulatory effect, leading to marked improvements in vegetative growth and yield, as well as enhancing tuber quality through improved nutrient uptake, activation of metabolic activity, and increased accumulation of carbohydrates, including dry matter, starch content, and specific gravity of tubers. It also contributed to the overall enhancement of plant physiological efficiency. The combined treatments of salicylic acid and chitosan showed a clear synergistic effect compared with individual applications. The treatment (100 mg L⁻¹ salicylic acid + 1.5 g L⁻¹ chitosan) recorded the highest values for most studied traits, including vegetative growth parameters, yield components, and tuber number, as well as quality traits such as dry matter, starch content, and specific gravity, in addition to improving nutritional content in terms of NPK and protein. This dominance is credited to a synergistic relationship between the two compounds in which salicylic acid can control physiological functions and increase the translocation of nutrients into the body as well as chitosan can increase metabolism, better nutrient absorption and accumulation of organic compounds. In general, the work proves the fact that Salicylic acid/chitosan combination is a beneficial and green agronomic approach to enhancing potato growth and quality of tubers in the field.