Summary: Harpin Use in Potatoes REPLICATED YIELD TRIALS WITH HARPINαβ PT-01-09 Details: Employ applied to foliage at 2.1 oz/acre in two regimes: 2 apps: end of set, and 3 weeks later (“X2”) 3 apps: end of set, 3 and 6 weeks later (“X3”) 2009 Trial Locations: Idaho: 5 Washington: 4

Summary: Harpin Use in Potatoes REPLICATED YIELD TRIALS WITH HARPINαβ Summary Across Trials for PT-01-09 & PT-02-09 On average, the treatments had fewer stems than the untreated control. Treated plants tended to be slightly shorter than untreated plants. Average of Trials 209089, 209090, 209091, 209092, 209093, 209095, 209097, 209109.

Summary: Harpin Use in Potatoes REPLICATED YIELD TRIALS WITH HARPINαβ Summary Across Trials for PT-01-09 & PT-02-09 Treated plants had higher early vigor than untreated plants. Treated plants had more tubers than untreated plants. Average of Trials 209089, 209090, 209091, 209092, 209093, 209095, 209097, 209109.

Summary: Harpin Use in Potatoes REPLICATED YIELD TRIALS WITH HARPINαβ Summary Across Trials for PT-01-09 & PT-02-09 Treated plants had substantially higher gross yields than untreated plants. Treated plants had substantially higher marketable yields than untreated plants. Average of Trials 209089, 209090, 209091, 209092, 209093, 209095, 209097, 209109.

Summary: Harpin Use in Potatoes REPLICATED YIELD TRIALS WITH HARPINαβ Summary Across Trials for PT-01-09 & PT-02-09 UTC Employ X3 Employ X2 Gross Crop Value $3,242 $3,578 $3,542 Cost of Treatment $ - $63.00 $42.00 Net Crop Value $3,546 $3,521 Net Gain $ $305 $279 ROI   9.7 13.3 The 2 application regime had a lower net gain but a higher ROI than the 3 application regime. Crop value was calculated using 2009 Idaho fresh market prices of $8.50 for US#1, $6.00 for US#2, and $2.00/cwt for usable culls; and $10.50/oz for Harpinαβ. Percent increase ranged from 7.4% to 8.7%. Average of Trials 209089, 209090, 209091, 209092, 209093, 209095, 209097, 209109.

Summary: Harpin Use in Potatoes REPLICATED YIELD TRIALS WITH HARPINαβ Summary for PT-01-09 & PT-02-09: On Average: treatments had no statistical effect on stand, stem number, vigor and plant height treatments increased tuber set, ranging from 22% to 23% - may have been applied a bit early treatments increased gross yield, ranging from 7.4% to 7.7% treatments increased marketable yield, ranging from 8.1% to 8.7% Average of Trials 209089, 209090, 209091, 209092, 209093, 209095, 209097, 209109.

Summary: Harpin Use in Potatoes REPLICATED YIELD TRIALS WITH HARPINαβ Summary for PT-01-09 & PT-02-09: Yield increases came primarily from increased set. Marketable yields were improved more than gross yields, demonstrating an increase in quality and improved crop value. Results were very similar to those seen with the timing trials and grower trials done with HarpinEa Comments? – Questions? Average of Trials 209089, 209090, 209091, 209092, 209093, 209095, 209097, 209109.