Title: Potato Variety Response to Phosphorus Fertilizer
1Potato Variety Response to Phosphorus Fertilizer
- Mike Thornton, Deron Beck, Jeff Stark and Bryan
Hopkins
2Petiole P status and yield are related
Y 237 7.24X 0.026 X 2
R 2 0.76
Source Westermann and Kleinkopf, 1983
3Daily uptake rate of P during three years at
Aberdeen, ID
Source Stark, Westermann and Hopkins, 2004
4Cultivar use in 2007
Washington
Oregon
Idaho
Shepody
56LS
6Do potato varieties differ in their response to P
fertilizer?
- Differences in yield response
- Differences in P uptake or petiole levels
- Differences in P removal by tubers
- Varieties with poor root systems or
susceptibility to early die might need more P
7Methods
- Split plot design with 4 rates of P2O5 (0,100,
200, 300 lbs per acre) broadcast as 11-52-0 and
incorporated prior to planting. Urea used to
balance N rates. - Four cultivars (Burbank, Ranger, Shepody, 6LS)
planted as subplots
Soil test values (0 to 12)
UI recommendation
Year pH Lime Soil P (ppm) Broadcast(P2O5/ac) Starter (P2O5/ac)
2005 8.2 1 15 130 lbs 40 to 80 lbs
2006 7.7 2 8 210 lbs 40 to 80 lbs
2007 8.2 1 5 290 lbs 40 to 80 lbs
8Influence of fertilizer rate on marketable yield
9Influence of fertilizer rate on tuber size
profile
Russet Burbank
6 LS
10Vine Growth
11Vine Growth
12Influence of fertilizer rate on plant growth
13Influence of fertilizer rate on petiole P
concentration
Deficient
14Influence of fertilizer rate on plant P uptake on
Aug 15
15Influence of fertilizer rate on P removal in
tubers
16SUMMARY
- Plant development was delayed and senescence
increased at low P rates, especially in Shepody - Petiole P levels were highest in Ranger, lowest
in Russet Burbank and 6LS - Ranger and 6LS had the strongest yield response
to fertilizer P, and removed up to 33 lbs/acre P
in tubers at harvest
17For information about potatoes, visit Idaho
Center for Potato Research and Education
http//www.ag.uidaho.edu/potato