IPI International Potash Institute
IPI International Potash Institute

Scientific abstracts

Phosphorus and Potassium Availability from Cattle Manure Ash in Relation to their Extractability and Grass Tetany Hazard
Thinh Tran, Q., M. Maeda, K. Oshita, M. Takaoka, and K. Saito
Published in:
Soil Science and Plant Nutrition 2018, English


Due to a decrease in phosphorus (P) and potassium (K) mining, manure is incinerated to concentrate P and K in ash. To understand the alternative use of manure-derived ash as P and K sources, laboratory and greenhouse experiments were conducted to determine the relationship between extractability and P and K uptake in cattle manure ash (CMA) and that between CMA application and a grass tetany hazard. The results showed that more P was extracted with 2% citric acid (90% of the total P) than with 2% formic acid (72-84% of the total P). Ninety-one percent of the total K was soluble in water. A greenhouse pot experiment was conducted to test P and K availability to Guinea grass (Megathyrsus maximus). Cattle manure ash or calcium dihydrogen phosphate (CF) was incorporated into sandy soil at 10, 20, and 50 g P2O5 m−2. Two combinations of CMA and CF were tested at 20 g P2O5 m−2. Potassium rates followed K content in CMA applied at different rates of P equivalent to 19, 38, or 96 g K2O m−2. In four harvests, there was no significant difference in the total yields between CMA and CF treatments. The total P uptake was significantly lower in the CMA treatment than in the CF treatment, while it was not in the combined CMA and CF treatments. The P uptake in response to different extraction methods indicated that the extraction of P by 2% formic acid without sonication is recommended to predict P availability in CMA. The potassium uptake from CMA application was comparable to that from the KCl application, and excessive K occurred at 38 and 96 g K2O m−2. The grass tetany hazard ratio higher than 2.2 was observed at the beginning period at the lowest application rates of CMA and CF. In conclusion, the combination use of CMA and CF was better than the single use of CMA. Moreover, CMA would be an available K source, but the grass tetany hazard still needs to be considered in application rates and pretreatments.

Return to the Scientific abstracts

In your Language

Choose your Crop

Choose your App
IPI research e-ifc app for iPad and iPhone available now from the Apple App Store
IPI Research App for Android and Apple phones and tablets.

The Role of Potassium (K) in the Plant (in Urdu)
Potassium and Nitrogen Use Efficiency (NUE) in Urdu
Potassium in Soil and Plant Systems (in Urdu)
IPI profile infographic
Chloride - an essential nutrient
Potassium and Nitrogen Use Efficiency (NUE)
Managing Water and Fertilizer for Sustainable Agricultural Intensification - infographic
Potassium Improves your Crop Quality
Potassium Improves your Health
Potassium in Soil and Plant Systems
The Role of Potassium (K) in the Plant
What does a Plant Need to Live
Assessment of the Impact of Targeted Use of Fertilizer on Irrigated Rice in Asia
The Role of Potassium (K) in the Plant (in Urdu)

New publication