Foliar fungicide treatments for control of stripe rust in spring wheat Bingham

摘要

The trial was established in a field at the university research farm in Bingham County, ID. The field had been cropped to green manure oats in the preceding year. The soil type was a DeA Declo loam of 0-2% slope, pH 8.0, and 0.9% organic matter. Experimental plots (5 x 13.3 ft planted, 5 x 9.3 ft harvested) of the stripe rust and Fusarium head blight (FHB) susceptible variety 'WestBred 936' (stripe rust infection type 9) were arranged in a randomized complete block design with 4 replicates. Plots ofWestBred 936 were also planted as spray buffer and rust spreader rows between plots. Seeding density was 1 million seed/A planted on 5 Apr. Row spacing was set at 7-in. with seven rows per plot, planted using a double disk opener with a Hege 500 series drill. Fungicide treatments were applied at herbicide timing A on 29 May when wheat plants were at Feekes 6-7 or Zadoks growth stage 31, application code B at flag leaf Feekes 10 or Zadoks GS 41-45 on 5 Jun , and application C at Feekes 10.51 or Zadoks growth stage 60 on 17 Jun. Phytotoxicity ratings were taken 7 days after application (DAA) for all application timings. The percent leaf area affected by stripe rust was rated 5 Jun, 12 Jun, 19 Jun, 26 Jun, 1 Jul and 10 Jul. Significant natural infection became apparent on 26 Jun. Senescence estimates were recorded as percent of plot senesced on 23 Jul. Plots were harvested 19 Aug with a small plot combine. Yield and test weight were determined with the HarvestMaster system on the combine, but a correctedtest weight was calculated after cleaning the grain from each plot on 12 Sep. Grain protein was measured 19 Sep utilizing a Foss 6500 NIR. Data were analyzed using ANOVA analysis in ARM 9 (Gylling Data Management, Inc., Brookings, SD). Fisher's protected LSD (alpha = 0.05) was used for mean comparisons.