| Autor: |
Ortel, C. C., Roberts, T. L., Drescher, G. L., Slaton, N. A., Ross, W. J., Hoegenauer, K. A., Followell, C. A. |
| Předmět: |
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| Zdroj: |
B.R. Wells Rice Research Studies - Arkansas Agricultural Experiment Station, University of Arkansas System; Feb2023, Issue 692, p43-48, 6p |
| Abstrakt: |
Recent advancements in soil testing and plant analysis have expanded potassium (K) management in soybean [Glycine max (L.) Merr.] from traditional preplant applications based simply on soil test results to also include profit-maximizing K rates using the economic potash rate calculator and in-season diagnosis of hidden hunger using tissue tests. The objective of this research was to validate K management strategies available for soybean, including traditional preplant applications, a reduced preplant rate according to the economic potash rate calculator, in-season granular fertilizer-K applications, in-season foliar fertilizer-K applications, and split fertilizer-K applications. The research was conducted as a randomized complete block design in 2022 on a Henry silt loam with Very Low soil-test K (STK). The site experienced dry weather and delayed irrigation, resulting in visual K deficiencies 15 days after R1 stage (DAR1), confirmed by trifoliolate leaf samples collected at 15 DAR1. The deficiencies were remediated by irrigation and in-season applications of granular fertilizer K. Regardless of the granular fertilizer-K rate, the addition of a foliar K source applied 2 gal/ac (4.6 lb K2O/ac) at 30 DAR1 did not significantly increase grain yield. Additionally, there was no significant yield difference when the same rate of granular fertilizer-K was applied all preplant compared to one-half preplant and one-half 15 DAR1. However, treatments that received additional in-season granular fertilizer-K applications did numerically outyield those which did not. Finally, the yield-maximizing K rate based on soil test values and the profit- maximizing K rate based on fertilizer and grain prices at the time of planting resulted in similar yields. Therefore, both the traditional yield-maximizing K rate and the reduced profit-maximizing K rate are successful management approaches when applied all at preplant or as split applications to include in-season granular fertilizer-K applications. [ABSTRACT FROM AUTHOR] |
| Databáze: |
Complementary Index |
| Externí odkaz: |
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