Sampling and phenology-related nutrient concentrations in mango in Southern Sinaloa, Mexico.
Benitez-Pardo D., Hernández-Montoya M., Osuna-Enciso T., Valenzuela-López M., Galván-Piña B.
Author Affiliation: Facultad de Ciencias del Mar, Paseo Claussen s/n, Apartado Postal 610, Col. Los Pinos, 82000 Mazatlán, Sinaloa, Mexico.
Terra 21 : 273-283
Abstract : Leaf samples were obtained monthly from 10 mango trees to determine the part of the canopy that should be sampled to obtain information on the nutritional requirements of mango at various phenological stages. Samples were obtained from the northern or southern side; lower, middle, or apical canopy; and subterminal (I) or terminal (II) internodes. The total N, K, Mg2+, and S, as well as N-NO3- and P-PO43- were higher before and after fruit bearing. Ca2+ decreased from 37.3 g kg-1 during fruit development to 31.3 g kg-1 during quiescence. N and Mg concentrations were higher on the southern side of the canopy, with 16.1 and 1.38 g kg-1, respectively, compared with 14.9 g kg-1 and 1.25 g kg-1 of the northern leaves. Most nutrients were more abundant in the lower and middle parts of the canopy. The young leaves of the terminal internode had higher total N content, with 16.1 g kg-1, but the older ones of internode I had a higher concentration of Ca2+ (35.1 g kg-1). The interaction among the variables was not observed. The results suggest that the samples should consist of two- to four-month-old leaves obtained from a wide zig-zag band of the middle canopy, either at monthly intervals or at each phenological stage.