Oakes
Russet Burbank In-furrow Fertilizer
Trial
H.
Hatterman-Valenti and C. Auwarter
This study was conducted at the Oakes
Irrigation Research Site near Oakes, ND, to evaluate rates of in‑furrow
fertilizer on Russet Burbank potato.
Soil tests showed 22 lbs N, 15 ppm P (high on the Olsen soil test
method), and 140 K (high on the Olsen soil test method). Corn was grown during 2012. Plots were 4 rows by 20 ft arranged in a
randomized complete block design with four replicates. 50 lbs N as 46-0-0 and 50 lbs K as 0-0-60 was
pre-plant incorporated prior to planting on entire plot. Seed pieces (2 oz) were planted on
36-inch rows and 12-inch spacing on May 15, 2013. Fertilizer was applied in‑furrow at 15 gpa as a stream on both sides of
the seed piece.
After
planting:
Treatment
1: 102 lbs N (22 lb soil test, 50 lb ppi, 30 lb @ plant as 28-0-0), 0 P
Treatment
2: 105.4 lbs N, 110.5 lbs P (3.6 lb as
WC139, 106.9 lb as 10-34-0)
Treatment
3: 104.3 lbs N, 105.1 lbs P
Treatment
4: 101.4 lbs N, 91.3 lbs P
Treatment
5: 104.5 lbs N, 118.8 lbs P
Treatment
6: 102 lbs N + WC041 @ 1 lb/ac
Maintenance
sprays, hilling, irrigation and additional N were applied as needed. N was applied once in late June and late July
at 50 lbs each time. Fifty percent
emergence occurred on June 7 (23 DAP) among all treatments. Each plot was four rows; however, fertilizer
was only applied on the middle two rows.
Fifty percent row closure occurred on July 16 (62 DAP). Potatoes were harvested on October 29 and
graded November 19.
The
highest yielding treatment occurred with 5 gal/ac WCI139 (6.1 lbs P) + 25
gal/ac 10-34-0 (99 lbs P)
(treatment 3) with a total yield of 544 cwt/ac. The lowest yielding treatment was treatment 1
with no P applied, at 396 cwt/ac.
Marketable yield (>4oz) showed the same trend with treatment 3 having
the highest (504 cwt/ac) and treatment 1 the least
(364 cwt/ac).
Tuber
counts in 20 feet of row showed treatment 3 with the highest count (154 tubers)
and treatment 1 with the least (111 tubers).
Treatment 2, 3 gal/ac WCI139 (3.6 lbs P) + 27 gal/ac 10-34-0 (106.9 lbs
P) had the second lowest number of tubers with 123 tubers. Treatments 4-6 had between 143 and 148
tubers. Treatment 3 also had the highest
percentage of marketable tubers with 72% of all tubers being greater than 4 oz. Treatment 6, 1 lb/ac WCI041 had the lowest
percentage of marketable tubers with only 64% of all tubers being
marketable. Treatment 1 had 67%
marketable tubers.
Oakes Irrigation Research Site