Fertoz: Evaluation of PhoSul in Central Montana

The purpose of this study was to evaluate the effectiveness of PhoSul as a phosphate fertilizer in dryland agricultural systems in the semi-arid climate of central Montana. Rainfall totals were 11.3 inches for the crop year, about 4 inches below the 110-year average. The mean annual temperature was 2.6°F higher than the 110-year average. July was the hottest month with an average monthly temperature of 72.9°F (6.9°F above normal). Total rainfall was 0.6 in June, only 20% of the average.
A winter wheat trial has been set up at MSU’s Central Agricultural Research Center (CRAC). The treatments were compared for height, propensity to lodge, date of heading, yield, test weight and protein. Each treatment was planted in four 5 x 16 foot plots in a randomized complete block design (RCBD) to determine treatment differences. The study was established in a field0 that was previously planted in a cover crop of lentils.
PhoSul was applied in furrow at 75 lbs/ac. Treatments consisted of PhoSul without starter fertilizer, PhoSul with Bacillus inoculant and 50 lb/ac 20:30:20:10 starter fertilizer, PhoSul with Bacillus inoculant and without starter fertilizer, control with 50 lb/ac 20:30: 20:10 starter fertilizer and without PhoSul, and a control without P without starter fertilizer. A Bacillus inoculant was included in this study due to the putative role Bacillus plays in phosphorus bioavailability.
The seeding date for the winter wheat study was November 5, 2020. Seeding depth was 1 inch at a rate of 60 lbs/ac. The study was sprayed with Vendetta on June 2 for broadleaf weed control. The coated slow release (46:0:0) urea was applied on June 10 at a rate of 195 lbs/acre. Plant height and lodging scores were recorded in the field. The study was harvested on August 3, 2021. Soil samples were also taken from the furrow and between the rows for the PhoSul treatment, control with starter fertilizer and control No P to determine if PhoSul contributed to the P available. Soil samples were submitted to Ward Laboratories (Kearney, NE) for Mehlich III-P analysis. The Mehlich III test is commonly used to provide an estimate of P available to plants.
Drought conditions led to below average yields for this study. Rainfall totals from April to July were 5.4 inches compared to the 100-year average of 8.6 inches (Table 1). Rainfall in June, a critical month for grain filling, was 0.6 inches, just 20% of average. Winter wheat with PhoSul alone produced 42.7 bushels/acre. This was a 36% higher yield than the starter fertilizer control and was statistically significant at p conclusion
Although winter wheat yields were significantly lower, due to drought, than the historical average of over 60 bushels/acre, a significant treatment effect was observed on yield. The proteins were variable but no significant differences were observed. This is probably partly due to the dry conditions. Slow release nitrogen was applied on June 10 and only 0.6 inches of rain was received that month. Fertilizer granules were still visible on the soil surface when mature.
Soil tests indicated that the PhoSul treatment had as much P available to plants as the controls with 50
starter fertilizer lbs/ac. In PhoSul and the control, P levels in the root zone were significantly
higher than the loose soil between the furrows. The control without fertilization showed no
difference in P concentrations between furrows and between furrows. These results suggest
that PhoSul is able to meet plant P requirements. Since the P concentrations were
virtually identical between PhoSul and the control, it seems unlikely that the yield will increase with
PhoSul was a P answer. PhoSul also contains S and amorphous silica, and it is possible that a
of these components contributed to the performance response.


Fertoz Ltd. published this content on July 11, 2022 and is solely responsible for the information contained therein. Distributed by Public, unedited and unmodified, on Jul 11, 2022 5:53:02 PM UTC.

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