Effect of potassium application rate and timing on alfalfa yield and potassium concentration and removal in Tennessee
Laen...
Kuupäev
2023
Kättesaadavus
Ajakirja pealkiri
Ajakirja ISSN
Köite pealkiri
Kirjastaja
Estonian University of Life Sciences
Abstrakt
Alfalfa (Medicago sativa L.) is the most important forage crop in the world and
potassium plays a significant role in achieving high yields. A field experiment was conducted
during the 2012–2014 growing seasons at the University of Tennessee in Springfield. The
experimental design was a split-split plot that included four levels of potassium (K) application
rates (0, 67.25, 134.50, and 269.00 kg K2O ha-1
) as the main plots and two K application times
(green-up and split) as the subplots, and harvest dates as sub-subplots. The results demonstrated
that the dry matter yield (DM) increased significantly with each increment in K application rate
up to 134.50 kg K2O ha-1
; however, the highest K fertilizer application (269 kg K2O ha-1
) did not
result in a significant yield increase relative to 134.50 kg K2O ha-1
, because some luxury
consumption of K occurred at the highest rate due to yield leveling off while K2O uptake
continued to rise. Potassium concentration and K removal increased with K fertilizer at rates
beyond those that maximized yield, indicating luxury consumption of K. The greatest K
concentration and removal were recorded at 269 kg K2O ha-1 in all harvest months. The split
application was more beneficial than applying full K at the time of green-up due to higher dry
matter, K concentration, and K removal in alfalfa. In conclusion, 134.50 kg K2O ha-1 is adequate
for maximizing alfalfa yield; split application of K is sometimes superior to the single dose of K
fertilizer in alfalfa production.
Kirjeldus
Received: December 1st, 2022 ; Accepted: March 15th, 2023 ; Published: April 13th, 2023 ; Correspondence: xyin2@utk.edu
Märksõnad
concentration, dry matter yield, fertilizer, Medicago sativa, nutrient removal, articles