Fecha/hora: 01/06/2024 04:05:45

Biblioteca(s): | INIA La Estanzuela.
Tipo de la producción científica: | Artículos en Revistas Indexadas Internacionales
Circulación/Nivel: | Internacional - --
Fecha corriente: | 28/11/2018
Fecha de la última actualización: | 28/11/2018
Autoria: | NÚÑEZ, A.; MORON, A.
Afiliación: | AGUSTIN NUÑEZ RUSSI, INIA (Instituto Nacional de Investigación Agropecuaria), Uruguay; DAVID ALEJANDRO MORON YACOEL, INIA (Instituto Nacional de Investigación Agropecuaria), Uruguay.
Título: | Potassium dynamics in western uruguayan agricultural mollisols.
Año de publicación: | 2017
Fuente/Imprenta: | Communications in Soil Science and Plant Analysis, 30 November 2017, Volume 48, Issue 21, Pages 2558-2572.
DOI: | 10.1080/00103624.2017.1416134
Idioma: | Inglés
Notas: | Article history: Received 4 January 2017 // Accepted 13 November 2017.

Contenido:

ABSTRACT.
Knowledge of soil potassium (K) dynamics and quantification of plant-available K reserves are essential for the correct management of this nutrient. The objectives of this study, conducted in six Uruguayan mollisols, were to (i) determine the contribution of plant-available nonexchangeable K to plant nutrition, (ii) compare the ability of the ammonium acetate (NH4OAc) method and the sodium tetraphenylboron (NaBPh4) method to determine plant-available K, and (iii) quantify the effect of K fixation and release processes on the ability of both methods to estimate changes in K availability due to different K balances. In a greenhouse experiment, perennial ryegrass (Lolium perenne, cv. Horizon) was grown over a period of 320 days in six soils fertilized with 0, 100, 200, and 400 mg K kg?1. We measured plant K uptake and the changes in soil K status related to different K balances using NH4OAc and NaBPh4. Use of NaBPh4 resulted in a more accurate determination of plant-available K (R2 = 0.97 vs. 0.78) and soil K balance (R2 = 0.73 vs. 0.63), but neither of the methods was suitable for identifying positive K balances. However, when positive balances were established by K addition and incubation without plant growth, both methods related well with K balances. Again, NaBPh4 was better than NH4OAc (R2 = 0.98 and 0.88, respectively). The more accurate determination of plant K uptake and the strongest relationship with K balance of NaBPh4 was due to the extraction of exchangeable K plus a proportion of plant-available nonexchangeable K. Soil?plant interactions enhance soil K fixation in forms that are available to plant absorption but are not extractable by the chemical methods considered in this study. 
© 2017 Taylor & Francis.

Palabras-Clave: | ILLITE; NONEXCHANGEABLE POTASSIUM; POTASSIUM RESERVES; SODIUM TETRAPHENYLBORON.
Categoría del tema: | --
Registro original: | INIA La Estanzuela (LE)
Ejemplares: | LE - (102628-1) - PXI - AP - DD -  -  -  - DIS