GROWTH AND QUALITY OF SEEDLINGS OF ARABIC COFFEE AS A FUNCTION OF BIOCHAR AND BIOFERTILIZERS IN THE NURSERY

Abstract

The physiological quality of seedlings in the nursery phase is essential to guarantee their adaptation and survival to post-transplant stress in the field. This study aimed to evaluate the biochar and biofertilizers effects on the growth and quality of arabic coffee seedlings in the nursery. The evaluated treatments were: biochar (T1), biofertilizer (T2), biochar + biofertilizer (T3), chemical fertilization (T4) and control (T5). The biochar was applied in doses of 20 g kg^-1 in the substrate. As a biofertilizer a native microbial consortium composed of bacteria, mycorrhizae, fungi and yeasts were applied in doses of 5 mL L^-1 using water. The main variables recorded were: dry matter content (g), leaf area index (cm²), relative growth rate (RGR), net assimilation rate (NAR) and Dickson's quality index. The results showed significant differences (p<0.05) for all variables evaluated. The T3 (biochar + biofertilizer) induced the highest production of both dry matter content and leaf area index per plant , with 8.28 g and 316.63 cm², respectively, in comparison with the other treatments here considered. In addition to, the T3 it was the best treatment regarding RGR and NAR at 30, 60 and 90-d old seedlings in the nursery. Finally the same T3 achieved the highest Dickson´s quality index, and it was positively correlated with the growth variables. It is concluded that biochar and biofertilizer can be used to improve the growth and quality of coffee seedlings in the nursery phase.