Seasonal variation of nutrients in mango (Mangifera indica) trees on three soils of the dry Pacific region of Costa Rica. II. Micronutrients.
Ponchner S., Rojas R., Bornemisza E.
Author Affiliation: Estación Experimental Agrícola Fabio Baudrit Moreno, Facultad de Agronomía, Universidad de Costa Rica, Alajuela, Costa Rica.
Agronomía Costarricense 17 : 31-37
Abstract : Nutritional status and seasonal variation of Mn, Zn, Fe, Cu and B were evaluated in mango trees (cultivars Irwin and Tommy Atkins) at 3 sites (the 3 most important mango-producing areas in Costa Rica) with different soil types - Atenas (Ustic Humitropept), Orotina (Typic Dystropept) and Liberia (Typic Ustropept). The leaves sampled were either terminal (new), intermediate or old, i.e. representing each of the last 3 growth flushes, and samples were taken each month. All the elements studied were immobile (their concentrations were greatest in the oldest leaves). In the case of Cu and Mn, the concentrations in the oldest leaves were >50% more than those in the youngest leaves. All the nutrients were found at higher concentrations in Tommy Atkins than in Irwin. B deficiency was observed at Atenas and Orotina, where soil B contents were also low. Zn deficiency was observed at all 3 orchards, corresponding to low soil Zn contents. Leaf Mn and Fe concentrations were much higher than the sufficiency ranges for mango, especially at Orotina, where soil pH was lowest. Mn, B and Fe uptake followed rainfall patterns, being highest during rainy periods. Sampling intermediate-aged leaves for determining micronutrient status is recommended.