EXTRACTING POTASSIUM FROM MANGO LEAVES

Potassium is an essential nutrient in mango production.
Tissue analysis is a useful tool for fertilization programs, and results affect orchard management and production costs.
We evaluated four plant potassium extraction methods in ‘Ataulfo’ mango leaf samples: 1) distilled water, 2) 65-70% nitric acid (HNO₃) and 69-72% perchloric acid (HclO₄) wet digestion, 3) 1.0 N ammonium acetate (CH₃COONH₄) pH 7.0, and 4) 0.5 M barium chloride (BaCl₂.2H₂O). Protocols (1) and (2) are the most commonly used methods.
Analytical quantification was achieved using atomic absorption spectrometry.
Potassium content was expressed as a percentage.
One hundred replications were used to evaluate each method.
Statistical treatment included random variance analysis, mean comparison with Tukey (P= 0.01), cluster analysis to determine canonical association between methods, and a technical aptitude test (Z–score). Each extraction method revealed a different capacity to dissolve mango leaf potassium: wet digestion extracted 0.9045%; distilled water 0.9707%; ammonium acetate 1.0 N, 1.0273%; and barium chloride 0.5 M, 1.2267%. The high activity of the 0.5 M barium chloride method allows for the exchange of potassium fixed in plant tissues, thus elevating levels of extraction.
The Z–score revealed a significant Euclidian distance which separated it from traditional methods that often yield underestimates.
Standardized field methods are currently under development.

VIII International Mango Symposium

I.J. González-Acuña, A. Llanos-Perales, B. Hurtado-García, F.P. Lang-Ovalle

potassium, extraction methods, leaves, mango

https://doi.org/10.17660/ActaHortic.2009.820.44