Glyphosate Resistance And The Impact On Agriculture

Transcription

1 Glyphosate Resistance And The Impact On Agriculture Jeff Stachler Extension Agronomist Sugarbeet / Weed Science NDSU and U of MN

2 Presentation outline 1. Why should we care about weed resistance?? 2. The situation in ND and MN 3. Defining high-level & low-level resistance 4. General solutions

3 Why should we care about weed resistance? No new novel herbicide site / mechanism of action is expected for the next 5 to 10 years! Reduced profits if resistant biotypes selected Weed resistance, most importantly multiple resistance continues to increase

4 Why should we care about weed resistance? Lost profit $12.00/A + $133/A $145/A Roundup PowerMAX (32 / 22 / 22 fl oz/a ) Ro-Neet (5.3 pt/a) [PPI] fb Betamix (12 / 16 / 24 fl oz/a) + Nortron (4 fl oz/a) + Outlook (14 / 10 fl oz/a) + Roundup PowerMAX (32 / 22 / 22 fl oz/a )

5 Why should we care about weed resistance? near Prinsburg, MN Crystal: 90% growers reported Excellent weed control with glyphosate SMBSC: 76% Excellent SMBSC Crystal Crystal: 81% growers reported Excellent weed control with glyphosate SMBSC: 59% Excellent

6 The Situation

7 Areas and counties of ND and MN having confirmed and suspected glyphosate-resistant weeds 2007 Gly-R common ragweed Gly-R giant ragweed Gly-R waterhemp Provided by: Drs. Jeff Stachler, Jeff Gunsolus, Mike Christoffers, and Kirk Howatt Black symbols: confirmed resistant cases; Blue: highly suspected

8 Areas and counties of ND and MN having confirmed and suspected glyphosate-resistant weeds 25 to 40% soybean fields gly-r C. Rag. 5 to 90% all fields gly-r waterhemp to 40% soybean fields gly-r C. Rag. 30 to 90% all fields have gly-r waterhemp 30 to 60% all fields gly-r C. Rag. 50 to 95% all fields have gly-r G. Rag. Gly-R common ragweed Gly-R giant ragweed Gly-R waterhemp Provided by: Drs. Jeff Stachler, Jeff Gunsolus, Mike Christoffers, and Kirk Howatt Black symbols: confirmed resistant cases; Blue: highly suspected

9 Waterhemp - Holloway, MN 2010 two glyphosate applications

10 Areas and counties of ND and MN having confirmed and suspected glyphosate-resistant weeds 5 to 50% soybean fields gly-r C. Rag. 5 to 95% all fields gly-r waterhemp to 95% all fields gly-r C. Rag. 70 to 95% all fields have gly-r waterhemp 60 to 95% all fields have gly-r G. Rag. Gly-R horseweed / marestail Gly-R kochia Gly-R common ragweed Gly-R giant ragweed Gly-R waterhemp Provided by: Drs. Jeff Stachler, Jeff Gunsolus, Mike Christoffers, and Kirk Howatt 30 to 60% all fields gly-r C. Rag. 5 to 95% all fields gly-r G. Rag. & waterhemp Black symbols: confirmed resistant cases; Blue: highly suspected

11 Waterhemp - Moorhead, MN 2011 two glyphosate applications

12 Waterhemp & common ragweed - SW Traill Co., ND Waterhemp

13 Common ragweed - E. of Nielsville, MN Better management Continuous RR soybean Better management Continuous RR soybean

14 Glyphosate-resistant kochia Stutsman and Pierce Co., ND 2011 (least activity) Untreated Check lb ae/a Rndp 10.7 fl oz/a 0.56 lb ae/a Rndp 16 fl oz/a 0.75 lb ae/a Rndp 21.3 fl oz/a lb ae/a Rndp 32 fl oz/a 1.5 lb ae/a Rndp 43 fl oz/a 3 lb ae/a Rndp 85 fl oz/a 6 lb ae/a Rndp 1.3 gal/a Pierce Co., ND Population Stutsman Co., ND Population Susceptible Check

15 Areas and counties of ND and MN having confirmed and suspected glyphosate-resistant weeds 15 to 90% soybean fields gly-r C. Rag. 5 to 95% all fields gly-r waterhemp to 60% all fields have gly-r kochia Gly-R horseweed / marestail Gly-R kochia Gly-R common ragweed Gly-R giant ragweed Gly-R waterhemp Provided by: Drs. Jeff Stachler, Jeff Gunsolus, Mike Christoffers, and Kirk Howatt 5 to 95% all fields gly-r G. Rag. & waterhemp Black symbols: confirmed resistant cases; Blue: highly suspected

16 Glyphosate-resistant kochia - Richland County, ND Photo from: Ingrid Kristjanson

17 Glyphosate-resistant kochia - McIntosh County, ND 2012 Also present: Horseweed (marestail), and Lambsquarters = kochia = horseweed

18 Locations of Run 1 samples tested 11-12

19 2012 Glyphosate-R test results 0.75 lb ae/a Rndp 21.3 fl oz/a 2.25 lb ae/a Rndp 64 fl oz/a Benson Co., ND Population Currently 29% of 38 samples have tested positive Richland Co., ND Population S R Susceptible Check

20 2012 Glyphosate-R test results 0.75 lb ae/a Rndp 21.3 fl oz/a 2.25 lb ae/a Rndp 64 fl oz/a Benson Co., ND Population Logan Co., ND Population S R Susceptible Check

21 Glyphosate-resistant horseweed in Cass County, ND % of field + 2 other fields <1% of field

22 Additional herbicide resistance issues 1. Fluroxypyr-R kochia 1. Present in 20 to 50% of fields in Central ND

23 Dicamba and fluroxypyr-resistant kochia Pierce Co., ND 2011 seed Untreated Check Starane Ultra Atrazine 0.5 lb ai/a Clarity 4.0 fl oz/a Clarity 8.0 fl oz/a 2.86 fl oz/a 5.7 fl oz/a 11.4 fl oz/a 22.8fl oz/a Salt spot Higher ground (no salt)

24 Counties of ND and MN having confirmed fluroxypyr (Starane)-resistant kochia % (2/2) = R Provided by: Drs. Jeff Stachler, Jeff Gunsolus, Mike Christoffers, and Kirk Howatt Black symbols: confirmed resistant cases; Blue: highly suspected

25 2012 Fluroxypyr-R test results 0.12 lb ae/a (1.9 oz ae) Starane Ultra 5.5 fl oz/a 0.25 lb ae/a (4 oz ae) Starane Ultra 11.4 fl oz/a Benson Co., ND Population Cavalier Co., ND Population S R Susceptible Population

26 Counties of ND and MN having confirmed fluroxypyr (Starane)-resistant kochia % (12/19) = R Provided by: Drs. Jeff Stachler, Jeff Gunsolus, Mike Christoffers, and Kirk Howatt Black symbols: confirmed resistant cases; Blue: highly suspected

27 Additional herbicide resistance issues 1. Fluroxypyr-R kochia??? 1. Potentially present in 20 to 50% of fields in Central ND 2. PPO-R common ragweed and giant ragweed 1. Likely present in Mahnomen Co., MN

28 Conventional Soybean in Mahnomen County, MN Flexstar (0.75 pt/a) 2 times

29 Additional herbicide resistance issues 1. Fluroxypyr-R kochia??? 1. Potentially present in 20 to 50% of fields in Central ND 2. PPO-R common ragweed and giant ragweed 1. Likely present in Mahnomen Co., MN 3. Bentazon-R biennial wormwood??? (ND) 4. Multiple herbicide resistance 1. PPO + ALS + glyphosate in waterhemp (MN & ND) 2. ALS + PPO + triazine + glyphosate in waterhemp (MN) 3. Fluroxypyr/dicamba/2,4-D + glyphosate in kochia (ND) 4. PPO + ALS in common ragweed (ND) 5. ACCase + ALS in wild oat and green foxtail (ND & MN) 5. Others??

30 Multiple resistance??? Cobra applied near Holloway, MN

31 Multiple-resistant waterhemp Resistant Check (IL) Holloway, MN Susceptible Check Untreated 1 pt Flexstar + MSO + AMS 12.5 oz 1.5 pt 3 pt 4.5 pt 2 oz 0.9 oz 3 oz 6 oz 2.7 oz 37.5 oz 9 oz Cobra Ultra Sharpen Cadet + MSO Blazer + MSO + MSO + AMS + MSO + AMS + AMS + AMS Resource + MSO + AMS

32 Multiple-resistant waterhemp Resistant Check (IL) Holloway, MN Susceptible Check 3.5 pt 10.5 pt Flexstar GT MSO + AMS 19 oz 58 oz Touchdown HiTech + R-11 + AMS 1 qt 3 qt Aatrex + MSO + AMS 3 oz Callisto + MSO + AMS 0.38 oz 3 oz 9 oz + 1pt Harmony GT + MSO + AMS 9 oz + 3 pt Callisto + Aatrex + MSO + AMS

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34 Size at time of application Untreated Glyphosate + Flexstar Glyphosate + FirstRate Flexstar + FirstRate Glyphosate + Flexstar + FirstRate OH Progeny Susceptible 1X 4X 1X 4X 1X 4X 1X 4X

35 Multiple-resistant kochia lb ae/a Rndp 21.3 fl oz/a 2.25 lb ae/a Rndp 64 fl oz/a 0.12 lb ae/a (1.9 oz ae) Starane Ultra 5.5 fl oz/a 0.25 lb ae/a (4 oz ae) Starane Ultra 11.4 fl oz/a Benson Co., ND Population Cavalier Co., ND Population S R Susceptible Population

36 Defining High-Level & Low-Level Resistance

37 Types of Herbicide Resistance High-Level Resistance = Survival at rates > 10 times the labeled rate Application parameters (coverage, environment, etc.) unlikely to affect control of species!! Usually minimal injury The correct rate usually does not matter when initially selecting Second applications usually do not reduce seed production! Usually single gene change of target site Examples = triazine, ALS, and ACCase

38 Types of Herbicide Resistance Low-Level Resistance = Survival at rates < 10 times the labeled rate Many different application parameters (coverage, environment, etc.) likely to affect control of species!! Significant injury always occurs initially & CAN kill small plants The correct rate DOES matter when initially selecting!!! Second applications USUALLY REDUCE numbers of plants & seed production! May be multiple or single gene changes in target site or other sites Examples = glyphosate, PPO, synthetic auxins, paraquat

39 Take-home message about resistance vs. tolerance Resistance A change in response in the weed populations to the herbicide. Resistant biotypes will increase over time. Tolerance No change in response in the weed population to the herbicide. Tolerant species should increase more rapidly than resistant biotypes.

40 Solutions

41 Solutions to weed resistance Scout 5 to 14 days after EACH herbicide application. Observe individual plant responses!!

42 Response of a resistant waterhemp population Injured Dead Normal

43 Continuous response of common ragweed to glyphosate Picture from Al Cattanach

44 Continuous response of a susceptible kochia population to glyphosate Dead (40%) Intermediate (9%) Resistant Nearly Dead (36%) Best survivors (14%)

45 Continuous response of kochia to glyphosate

46 Continuous response of kochia to glyphosate

47 Website address for video Scouting for Glyphosate Resistance :

48 Solutions - Understand Impact of ONE Weed

49 Single waterhemp plant in 2011 (Clay County, MN) actual seed number per plant = 142,000 Scenario: seed number on 1 plant in 1 acre = 100,000 seeds

50 Scenario If 25% (40% is possible) of seeds emerge next season (2012) Only 10% of emerged plants are resistant Same herbicide is applied as previous year How many plants may be present in 1 acre at the end of the season (2012)?

51 2,500 plants/a 1 year later (2012)

52 6,250,000 plants/a!! - 2 years later (2013)

53 Field perimeter management (2010)

54 Ramifications of not managing field perimeter (2011)

55 Ramifications of not managing field perimeter (2012)

56 Management of weeds along crop edges Future problem! The Goal!

57 Solution Practice ZERO TOLERANCE (no seed rain) Hand-weeding Remove / destroy surviving plants by hand from a field, especially when there are just a few! There in no better way to STOP the increase of resistant biotypes. Single plant Small patch Or row cultivate and hand-weed

58 Solution Practicing ZERO TOLERANCE (no seed rain) 52% of AR cotton hand-weeded in 2011 Average cost = $29.43/A (beets = $21.00/A) Proactive hand-weeding - $4-5/A 2010 hand-weeding 110 hours/50 acres ($22/A) 2011 hand-weeding 5 hours/50 acres ($1/A) ND Grower Website Stewardship Practices: Weed Control We strive to manage weeds to provide nearly 100% weed control in all crops and even those on the perimeter. We re tough on weeds, but not on the land. IL Land Lease: Weed Control The Landlord and Tenant agree that control of weeds is an extremely important aspect of crop production. If herbicidal treatment fails to control weeds and subsequent retreatment(s) also fail, then Tenant shall be solely responsible to use mechanical methods to control weeds including but not limiting to hand hoeing, hand pulling, and cultivation. Tenant that will minimize the risk of for resistance weeds.

59 Solution Practicing Zero Tolerance 1 hr/50 A = 0.02 hr/a 0.02 hr/a X 5000 A = 100 hrs 100 hrs 10 hrs/day = 10 days 100 hrs X $10/hr = $1,000 Vs $133/A X 5000 A = $665,000 Vs $20/A X 5000 A = $100,000

60 Solution Respond quickly!

61 Solution Understand impact of weed seed movement Means of dispersal: Water (especially for waterhemp) Machinery Wind Humans Animals / birds MPR Photo/Ann Arbor Miller

62 Movement of waterhemp seeds by 2011 flood To McLeod, ND 15 mi. upstream Direction of water movement

63 Solutions Diversify weed management Greater crop rotation Start clean! Use PRE herbicides in ALL crops Rotate herbicide mechanisms of action Tank-mix PRE and POST herbicides Maximize herbicide activity Apply POST herbicides to small (< 3 weeds) Optimize coverage Use best adjuvant(s) and at highest rate Maximize cultural practices Maximize quick crop canopy closure

64 Control of glyphosate-r common ragweed Mayville 9-25 Herbicide Program RR Soy LL Soy Roundup / Liberty (2 times) Roundup / Liberty + Flexstar/Cobra/Cadet fb Rndp / Lib 73 (93/34) 98 Roundup / Liberty + Outlook + Cobra fb Rndp / Lib PRE*** fb Roundup / Liberty (2 times) PRE** fb Roundup / Liberty + Flexstar fb Rndp / Lib PRE* fb Roundup / Liberty + Cobra + Outlk/Wrrnt fb Lib *** 1. Boundary (1.8 pt/a) {59%} 2. Prefix (1.75 pt/a) {69%} 3. Valor (2.5 oz/a) + Dimetric (5.33 oz/a) {76%} 4. Fierce (3.0 oz/a) {44%} 5. Sharpen (1 fl oz/a) + Zidua (2.5 oz/a) {67%} 6. Verdict (5 fl oz/a) + Zidua (2.5 oz/a) {68%} ** 1. Boundary (1.8 pt/a) 2. Verdict (5 fl oz/a) + Zidua (2.5 oz/a) * 1. Verdict (5 fl oz/a) + Zidua (2.5 oz/a)

65 Yield of RR/LL soybean - Mayville Herbicide Program RR Soy LL Soy % of Roundup alone Roundup / Liberty (2 times) (8.1 bu/a) Roundup / Liberty + Flexstar/Cobra/Cadet fb Rndp / Lib Roundup / Liberty + Outlook + Cobra fb Rndp / Lib PRE fb Roundup / Liberty (2 times) PRE fb Roundup / Liberty + Flexstar fb Rndp / Lib PRE fb Roundup / Liberty + Cobra + Outlk/Wrrnt fb Lib

66 Herbicide, adjuvant, app., & seed costs - Mayville Herbicide Program RR Soy LL Soy $ (% of Glyphosate alone)* Roundup / Liberty (2 times) (174) (100%-$25) Roundup / Liberty + Flexstar/Cobra/Cadet 106 (46) 108 (122) Roundup / Liberty + Outlook + Cobra fb Rndp / Lib 114 (-8) 118 (82) PRE fb Roundup / Liberty (2 times) 112 (157) 119 (129) PRE fb Roundup / Liberty + Flexstar 125 (161) 134 (214) PRE fb Roundup / Liberty + Cobra + Outlk/Wrrnt fb Lib 143 (38) 150 (-40) App. Fee = $5.00/A/app. Seed costs = $60.84 (RR) & $51.81 (LL) Soybean price = $14.00 Cost (Profit)*

67 Final reminders You have a choice! Delay resistance OR Ignore it

68 Final reminders - Leave a Legacy! The future success of your farming operation depends upon the weed control practices you choose today! Glyphosate is the most effective herbicide ever discovered, so let s work together to preserve it s effectiveness! THE Goal!

69 Thank You! ANY questions? Contact information (Office) (Cell) Resources