Cultivtion for Weed Control in in Sugreet Austin Neuuer, Nthn Hugrud nd Tom Peters, SMBSC, NDSU nd Univ. of MN
Summry of Cultivtion Reserch in Sugreet Nthn Hugrud nd Tom Peters, NDSU
Sugreet Weed Mngement in 2018 Limited POST control options Hericide resistnt pigweeds (wterhemp nd Plmer mrnth) Loss of historicl hericides (des+phenmediphm, Betmix ) Chlorocetmide hericides soil pplied (lyy) POST to sugreet, PRE to weeds (Peters et l. 2017) Renewed interest in cultivtion T. Peters (2018)
Inter-row Cultivtion Benefits: Non-selective mode of ction No risk of resistnce Incorportion of fertilizer nd hericide Drwcks: Limited re Potentil yield dmge (Dexter et l. 2000; Giles et l. 1990) Incresed disese risk (Schneider et l. 1982)
Cultivtion Reserch NDSU Extension 2016 Questions Cultivtion to remove hericideresistnt weeds? Effects on weed emergence? Interctions with residul hericide? Incorportion nd ctivtion Dmge to n estlished hericide rrier? Negtive effects on sugreet yield nd qulity?
Hericide pplied t stndrd rtes, volume, & pressure Hericide: Four/six levels Glyphoste lone Gly + Dul Mgnum Gly + Outlook Gly + Wrrnt Gly + Trefln Gly + Ro-neet
Cultivtion t 4 MPH nd 1.5-2 depth
# Wterhemp per plot Cultivtion immeditely fter hericide resulted in 50-75% less wterhemp, 14 DAT 7 6 5 4 3 2 1 0 15 inch sweeps / 22 inch rows = 68% re covered Renville, 2017 Hickson, 2018 Nshu, 2018 With cultivtion No cultivtion Cultivtion Hericide C X H Interction ANOVA Renville, 2017 Hickson, 2018 Nshu, 2018 All environments P-vlue 0.009 0.002 0.019 NS NS
% New wterhemp control Erly cultivtion generlly hd no effect on new wterhemp emergence control 100 95 90 85 80 75 Renville-2017 Hickson-2018 Nshu-2018 Renville-2017 Hickson-2018 Nshu-2018 14 DAT 28 DAT With cultivtion No cultivtion
% Overll wterhemp control Erly cultivtion resulted in 6-11% improved 100 95 90 85 80 75 70 65 60 overll control, 42 DAT Renville-2017 Hickson-2018 Nshu-2018 With cultivtion No cultivtion Initil removl of 65% of weeds + No effect on weed seedling emergence = Overll improved control Cultivtion Hericide C X H Interction ANOVA Renville, 2017 Hickson, 2018 Nshu, 2018 All environments P-vlue 0.008 0.002 0.041 NS NS
Hericide Cultivtion Erly cultivtion incresed common lmsqurters emergence, Glchutt-2018, 28 DAT With cultivtion No cultivtion Glyphoste Gly + Dul Mgnum Gly + Outlook Gly + Wrrnt Gly + Trefln Gly + Ro-neet Tretments pplied t 4-6 lf stge Light sensitive weed 0 10 20 30 40 50 60 70 80 90 # C. lmsqurters seedlings per m 2 ANOVA Cultivtion Hericide C X H Interction P-vlue 0.018 < 0.001 NS
% Overll C. lmsqurters control 100 95 90 85 80 75 70 65 60 55 50 Cultivtion t either timing hd no effect on overll C. lmsqurters control, 42 DAT Wheton-2017 Glchutt-2018 Wheton-2017 Glchutt-2018 Erly With cultivtion No cultivtion Delyed
Cultivtion Efficcy Summry Cultivtion cn remove out 2/3rds of weeds Generlly no effect on wterhemp emergence Cultivtion improved seson-long wterhemp control y 6 to 19% No effect on lmqurters control, ut risk for reduced seedling control if timed too erly Tke dvntge of crop cnopy y cultivting lter
Cultivtion Effect on Sugreet Yield Pst reserch from 1980s nd 1990s indicte yield loss from cultivtion in certin environments Incresed Rhizoctoni solni infection Moving soil-orne pthogen nerer its host Khn nd Bolton 2016 Grove 2017
Cultivtion Sfety: Experimentl Procedures Cultivtion every 2 weeks from June 21 to August 16 Crystl 355 plnted erly-my 4 MPH speed nd 1.5-2 inches deep Qudris (zoxystroin) for Rhizoctoni control
Cultivtion timing hd no effect on stnd mortlity or visul disese t ny environment Stnd mortlity Cultivtion timing Prosper Hickson Glyndon -------------------------%------------------------- Control 15 32-14 June 21 20 37-1 July 5 15 37 4 July 19 20 41-10 August 2 11 32-1 August 16 13 30 10 June 21 + July 19 13 31-7 July 5 + Aug 2 19 36 4 July 19 + Aug 16 21 39 7 June 21 + July 19 + Aug 16 16 37 7 ANOVA ----------------------p vlue---------------------- Tretment 0.082 0.435 0.848 Pre tretment stnd x 100 = % Stnd mortlity Hrvest stnd
Cultivtion timing hd no effect on sugreet yield cross ll environments in 2018 Yield Components Cultivtion timing Root yield Sucrose content RSA Tons/cre % Ls/cre Control 24.3 15.0 6,817 June 21 24.1 14.8 6,773 July 5 24.7 14.9 6,934 July 19 23.5 14.9 6,563 August 2 25.4 14.7 6,899 August 16 24.4 14.5 6,529 June 21 + July 19 24.3 14.5 6,679 July 5 + Aug 2 24.7 14.6 6,698 July 19 + Aug 16 23.5 14.8 6,472 June 21 + July 19 + Aug 16 23.5 14.8 6,540 ANOVA ----------------------------------p vlue---------------------------------- Tretment 0.944 0.062 0.947
Conclusion: Cultivtion timing hd no effect on sugreet yield, stnd density, or disese in 2018 Differences etween our experiments nd previous reserch Similr cultivtion methods, ut different timing nd intervls Dexter et l. (2000) nd Giles et l. (1990) implemented weekly cultivtion from mid- June to lte-july Differences in production prctices in 2018 vs the 1990s Seed tretments nd soil-pplied Qudris (zoxystroin) Crystl 355, diploid, is reltively resistnt to R. solni
The Future of Cultivtion: 2019 nd Beyond Vlule tool to removl weeds tht hericide did not/will not control Timing is key: cultivte ner crop cnopy closure No effects on weed emergence if shde is present No effect on yield in 2018, ut repets in future yers re needed Integrted Weed Mngement Chemicl