Weed Control in Grain Sorghum

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Weed Control in Grain Sorghum Powered By Docstoc
					   The Effect of Spray Tips and Spray
  Volumes on Glyphosate and Paraquat
                 Efficacy




Cathy L. Minihan, Dallas E. Peterson, Robert E. Wolf, & J. Anita Dille
             INTRODUCTION
• Higher spray volumes and smaller spray droplets
  theoretically should provide the most thorough
  coverage assuming the spray droplets reach the
  intended target.

• Spray volume, pressure, and spray tips influence
  spray droplet size.

• Thorough spray coverage is probably more critical
  with contact than systemic herbicides.
                OBJECTIVE

• Determine the effect of spray tips and spray

 volumes on paraquat and glyphosate efficacy with

 early and late postemergence applications to oats.
    MATERIALS AND METHODS
• Location & Years:      Manhattan, KS
                         2000, 2001

• Experimental Design:   2 x 3 x 3 Factorial
                         Herbicides
                         Spray Tips
                         Spray Volumes

•   Herbicides:          Glyphosate & Paraquat

•   Spray Tips:          XR Flat Fan
                         Turbo TeeJet
                         Air Induction
  MATERIALS AND METHODS
• Spray Volumes:         47 L ha-1 (110015)
                         94 L ha-1 (11003)
                         187 L ha-1 (11006)

• Spray Pressures:       262-276 kPa

• Early Postemergence:   Oats 15 cm
• Late Postemergence:    Oats 50 cm

• Visual Ratings:        1, 2, 4 WAT
XR Flat Fan   Turbo TeeJet   Air Induction
RESULTS AND DISCUSSION


EARLY POSTEMERGENCE
     EXPERIMENTS
       2000-2001
Early Postemergence Oat Control 2 WAT As
 Influenced By Herbicide and Spray Tips,
      2000. (averaged across spray volumes)
                   100       a
                         a            XR         TT       AI
                    90            b
                    80
                    70
                                             c
       % Control




                                                      c
                    60
                    50                d
                    40
                    30
                    20
                    10
                     0
                         Glyphosate       Paraquat
Early Postemergence Oat Control 2 WAT
 As Influenced By Spray Volume, 2000.
     (averaged across herbicides and tips)


                 100
                  90                         LSD(0.05)=NS
                  80
                  70
     % Control




                  60
                  50
                  40
                  30
                  20
                  10
                   0
                       47            94             187
                                               -1
                            Spray Volume ( L ha )
Early Postemergence Oat Control 2 WAT As
    Influenced By Herbicides and Spray
  Volumes, 2001. (averaged across spray tips)

                 100
                       a                    47         94       187
                 90
                 80
                               b
                                                 c      c
                 70                     d                       d
     % Control




                 60
                 50
                 40
                 30
                 20
                 10
                   0
                           Glyphosate                Paraquat
  Early Postemergence Oat Control 2 WAT
      As Influenced By Spray Tips And
   Volumes, 2001. (averaged across herbicides)

                                                         XR       TT       AI
            100
             90   b   a
                           bc       cd   de     e
             80                                               f
             70                                          fg            g
% Control




             60
             50
             40
             30
             20
             10
              0
                      47                 94                   187
                                Spray Volumes (L ha-1)
          EARLY POSTEMERGENCE

2000
       HERBICIDE X SPRAY TIP       SIGNIFICANT
       SPRAY VOLUMES           NOT SIGNIFICANT

2001
       HERBICIDE X VOLUME         SIGNIFICANT
       SPRAY TIP X VOLUME         SIGNIFICANT
LATE POSTEMERGENCE

   EXPERIMENTS

     2000-2001
Late Postemergence Oat Control 2 WAT
  As Influenced By Spray Tips, 2000.
   (averaged across herbicides & volumes)

                100
                 90                     LSD(0.05)=NS
                 80
                 70
    % Control




                 60
                 50
                 40
                 30
                 20
                 10
                  0
                      XR      TT             AI
                           Spray Tips
Late Postemergence Oat Control 2 WAT
As Influenced By Spray Volumes, 2000.
   (averaged across herbicides & spray tips)

                100
                 90
                 80
                      a               a
                 70                                 b
    % Control




                 60
                 50
                 40
                 30
                 20
                 10
                  0
                          47              94            187

                               Spray Volume ( L ha-1)
Late Postemergence Oat Control 2 WAT
  As Influenced By Spray Tips, 2001.
   (averaged across herbicides & volumes)

                 100
                  90                     LSD(0.05)=NS
                  80
                  70
     % Control




                  60
                  50
                  40
                  30
                  20
                  10
                   0
                       XR      TT             AI
                            Spray Tips
Late Postemergence Oat Control 2 WAT
 As Influenced By Herbicide and Spray
 Volumes, 2001. (averaged across spray tips)
                                    47   94   187
             100   a                                b      c
              90            c
              80
                                                                   d
              70
 % Control




              60
              50                    e
              40
              30
              20
              10
               0
                       Glyphosate                       Paraquat
          LATE POSTEMERGENCE

2000
       SPRAY VOLUME           SIGNIFICANT
       SPRAY TIPS         NOT SIGNIFICANT

2001
       HERBICIDE X VOLUME     SIGNIFICANT
       SPRAY TIPS         NOT SIGNIFICANT
    47 L ha-1             94 L ha-1           187 L ha-1




Late postemergence paraquat 1 WAT applied with spray
          volumes of 47, 94, 187 L ha-1, 2000.
      47 L ha-1             94 L ha-1            187 L ha-1




Late postemergence glyphosate 1 WAT applied with spray
          volumes of 47, 94, 187 L ha-1, 2000.
      47 L ha-1              94 L ha-1            187 L ha-1




Late postemergence oat control 2 WAT with glyphosate at
      47, 94, and 187 L ha-1 spray volumes , 2000.
               CONCLUSIONS
• Even though oat control with glyphosate and
  paraquat was different, the response to spray
  tips and spray volumes was similar.

• Oat control at 47 and 94 L ha-1 was equal or
  better than at 187 L ha-1 with both herbicides.

• Oat control with the Turbo Teejet, Air Induction,
  and XR Flat Fan tips was similar.
                IMPLICATIONS

• Lower spray volumes can provide equal or better
  weed control with more efficient use of time and
  resources.

• Use of new spray tips that produce larger spray
  droplets reduce the risk of spray drift while
  maintaining herbicide efficacy.
           FUTURE RESEARCH


• Confirm results with different herbicides and weeds.

• Evaluate new spray tips and delivery systems as
  they are introduced into the market.
        ACKNOWLEDGEMENTS

• Kansas State University
    Research and Extension

• Syngenta

• Successful Farming

				
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posted:9/27/2012
language:English
pages:25