Impact of K2SiO3 and luminosity in the nutrition and growth of Genipa americana

Foliar application of potassium silicate (K2SiO3) has been demonstrated to be a promising alternative for induced tolerance. We aimed to evaluate the effect of applying K2SiO3 on the nutrition and growth of Genipa americana L. seedlings under two luminous ambiences. Four doses of K2SiO3 via foliar spray were tested: 0.0, 2.5, 5.0, and 10.0 mL L–1, and cultivation under full sun or shade. We observed higher N content in seedlings under the full sun at 45 days and decreased with increased K2SiO3 doses in the same ambience at 90 days, while P, K, Ca, and Mg were higher in shaded seedlings and with 10.0 mL L–1 K2SiO3 at 45 and 90 days. The order of nutritional requirements for most seedlings, regardless of cultivation conditions, was K > N > Ca, with an inversion of Mg to P requirement with 10.0 mL L–1 K2SiO3. Shaded seedlings showed better growth at 45 and 90 days, but K2SiO3 contributed to photoassimilate accumulation under full sun. Foliar application of 5.0 mL L–1 K2SiO3 contributed to greater stem diameter, leaf area, and Dickson quality index. Foliar application of K2SiO3 alleviated the stressful effects of full sun and favored the nutrition and quality of G. americana seedlings.