1 / 12

Weed control & Crop Tolerance to Broadcast Flaming as Impacted by Time of Day

Weed control & Crop Tolerance to Broadcast Flaming as Impacted by Time of Day. Stevan Knezevic et al. University of Nebraska. “ Our Flame Weeding Team ”. Agronomy Department & Haskell Agricultural Lab: Dr. Stevan Knezevic & Dr. Jon Scott (Weed Technologist)

charisse
Download Presentation

Weed control & Crop Tolerance to Broadcast Flaming as Impacted by Time of Day

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Weed control & Crop Tolerance to Broadcast Flaming as Impacted by Time of Day Stevan Knezevic et al. University of Nebraska

  2. “Our Flame Weeding Team” • Agronomy Department & Haskell Agricultural Lab: • Dr. Stevan Knezevic & Dr. Jon Scott (Weed Technologist) • Santiago Ulloa (PhD student) & Dr. Avishek Datta (Post Doc) • Heverton Teixiere, Andray Domingous, Claudio Costa, Jaymo Nato, Sidnei (Brazil) • Pierre Marteau (France), Robert Leskovsek (Slovenia), • Dr. Goran Malidza, Igor Elezovic, Strahinja Stepanovic (Serbia) • Department of Mechanical Engineering: • Dr. George Gogos and Chris Bruening (PhD student), Brian Nelson, (MS) Jared Miller and Dustin Simpson • - Organic producers: Liz Sarno, Mike Ostry, Larry Stanislav, Randy Fendrich, Gerald Humlicek, Paul and Dan Huenefeld , Mark Ramaeker

  3. Introduction • Variability in flaming efficacy has been observed following early or late day flaming applications. • The variation in leaf relative water content (RWC) at various times of day is thought to contribute to this differential response. • Leaf RWC is a ratio of the amount of water in the leaf tissue at sampling compare to when fully turgid.

  4. Objectives • To describe DOSE RESPONSE CURVES for time of day as influenced by propane rates on 4 species • (green foxtail, velvetleaf, soybean and maize). • To select PROPANE dose from the curve to: • - Minimize crop injury • - Maximize weed control

  5. Greenhouse Study: • 4 flaming times: 6AM, 10AM, 2PM and 6PM • 4 propane rates: 0, 30, 60 and 90 kg/ha • 4 species: green foxtail, velvetleaf, soybean and maize • Air Temp, Rel-Hum. light and RWC were recorded at treatment application • RWC was measured @ procedure modified from Barrs and Weatherley (1962) • It is a function of the relative water content (RWC) • - RWC is the ratio of the water volume in a leaf to the maximum water volume of the leaf at full turgor. • - Typically, RWC is high in the AM and lower in PM hours

  6. RWC during day time All plant species presented the lowest RWC around 6 to 9 hours after sunrise

  7. Results: Green foxtail flamed with 90kg/ha (~ 18GPA) Control 6am 10am 2pm 6pm

  8. Velvetleaf flamed with 90kg/ha (~18GPA) Control 6am 10am 2pm 6pm

  9. Plant injury at different rates as influenced by time of day

  10. Conclusions • Flame weeding is more effective if conducted in the afternoon, but crop injury will be higher, regardless of the propane rate. • Practical implications • Flaming could be done around the noon time in order to obtain the maximum weed control with the minimum crop damage. • May not be always possible with large fields

More Related