Effect of Enerplant® doses on the development and nutrient use by cacao (Theobroma cacao L.) seedlings

Objective: To evaluate the effect of the application of doses of a biostimulant on the development, absorption and efficiency of nitrogen, phosphorus and potassium utilization by cocoa seedlings. Design / methodology / approach. In a completely randomized design, 4 doses of Enerplant® (0; 1; 2; 3 and 4 mL ha-1.) applied to cocoa seedlings grown under saran mesh were studied. The biostimulant was applied monthly via foliar. To determine the absorption of nutrients, 3 plants of each treatment were divided into leaves, stems and roots, dried for 72 hours at 65 ° C; they were ground, packaged, labeled, and sent to the laboratory, where the macronutrients of each component were determined. Results. The cocoa seedlings responded positively to the application of the biostimulant. As an average of the two years of study, Enerplant® in doses of 1 mL ha-1 significantly increased height (24%), dry mass (30%); the quality index (58%) and the foliar area (56%) of the cocoa seedlings. Doses higher than 1 - 2 mL ha-1 decreased plant growth. The pattern of nutrient absorption by cocoa in the nursery phase behaved in the order potassium> nitrogen> phosphorus Conclusions. The efficiency of nutrient utilization, regardless of the Enerplant® dose applied, was higher for phosphorus followed by nitrogen and finally potassium The application of the biostimulant in doses of 2 ml ha-1 guaranteed the highest absorption and efficiency values of utilization of macronutrients by cocoa seedlingsObjective: To evaluate the effect of the application of biostimulant doses on the development, absorption, and use efficiency of nitrogen, phosphorus, and potassium by cacao seedlings. Design/Methodology/Approach: Five doses of Enerplant® (0, 1, 2, 3, and 4 mL ha-1) were applied to cacao seedlings grown under a saran mesh. The study was carried out using a completely randomized design. The foliar area received a monthly application of the biostimulant. In order to determine the nutrient absorption, 3 plants per treatment were divided into leaves, stems, and roots; they were subsequently dried for 72 h at 65 °C. Finally, they were ground, packaged, labeled, and sent to the laboratory, where the macronutrients of each component were analyzed. Results: The cacao seedlings had a positive response to the biostimulant application. In average, the results of our two-year study were: 1 mL ha-1 doses of Enerplant® significantly increased height (24%), dry mass (30%), quality index (58%), and foliar area (56%) of the cacao seedlings. Doses higher than 1- and 2-mL ha-1 decreased plant growth. The nutrient absorption by cacao in the nursery stage followed the following pattern: K > N > P. Findings/Conclusions: The efficiency of nutrient use —regardless of the Enerplant® dose applied— was higher for P, followed by N and, finally, K. Applying 2 mL ha-1 doses of the biostimulant guaranteed the highest absorption and use efficiency values of macronutrients by cacao seedlings