Nutrient critical levels and availability in soils cultivated with peach palm (Bactris gasipaes Kunth.) in Santo Domingo de Los Tsáchilas, Ecuador

Ecuador is the most important exporter of canned peach palm, however, to date ideal soil fertility characteristics for peach palm growers remain unknown. The aim of this research was to determine optimal levels of soil nutrients for the cultivation of peach palm, specifically with regards to soil cation exchange capacity in order to obtain higher yields. We worked with 20 farmsteads and their soils from the province of Santo Domingo de los Tsáchilas during the second half of 2014. Fields were evaluated based on a relative yield and extractable (modified Olsen) nutrient contents in each soil were determined using regression modeling to determine critical levels of each nutrient and specifically to determine the ideal soil cation exchange capacity under peach palm cultivation. Our analysis established critical levels of soil pH (6.3); OM 6.5%; P 12.3 mg.dm-3; K 0.67 cmol.dm-3 K; Ca 5.1 cmol.dm-3 ; Mg 0.97 cmol.dm-3; and S 7.5 mg.dm-3. The ideal Ca: Mg: K soil cation exchange capacity was determined to be 76:14:10.