Research Article

Foliar Potassium Fertilizer Additives Affect Soybean Response and Weed Control with Glyphosate

Table 4

Soybean injury and weed control from fertilizer additives applied alone in a weed-free plot and tank-mixed with glyphosate plus non-ionic surfactant 14 days after treatment (DAT) at Portageville in 2004 and 2005 in weedy plots. Palmer amaranth, ivyleaf morning glory, and large crabgrass control of fertilizer additives plus glyphosate and nonionic surfactant 21 DAT at Portagevillea. Data were combined over years.

Fertilizer additivebRate (Kg K ha−1)Injury
2004 2005
Weed-freecGlyphosate tank mixtureWeed-freecGlyphosate tank mixturePalmer amaranthIvyleaf morninggloryLarge crabgrass
(%)

Non-treated00000
Weed-free0c0100100100
NIS02959594
NIS + DAS01918590
2.25600959596
0-0-62-0 8.85520949695
17.6510510959696
2.251013969797
3-18-18-0 8.80411969697
17.64342969695
2.23510969696
0-0-25-17 8.80373959695
17.630810939593
2.24032959496
5-0-20-13 8.83513959492
17.65101810959696
LSD (P = 0.01)87556

aAbbreviations: DAS, diammonium sulfate; DAT, days after treatment; KTS, potassium thiosulfate; NIS, non-ionic surfactant.
bFertilizer additives included 3-18-18, K phosphate + urea (NA-CHURS/ALPINE); 0-0-25-17, K thiosulfate; 5-0-20-13, K thiosulfate + urea-triazone (Trisert-K, Tessenderlo Kerley); and 0-0-62, potassium chloride. All tank mixtures with glyphosate included non-ionic surfactant.
cTreatment was not included.