Root Rot: Have you heard (or had) enough yet? Julie Pasche Pulse Crop Pathology Group

Transcription

1 Root Rot: Have you heard (or had) enough yet? Julie Pasche Pulse Crop Pathology Group

2 Pulse Pathology Dr. Michael Wunsch Carrington REC Audrey Kalil Williston REC Fargo Pathology Group Dr. Kirstin Simons Dr. Kim Zitnick-Anderson Amanda Beck Cecilia Monclova-Santana Chryseis Modderman Robin Lamppa 2

3 Root Rot Management An integrated approach Breeding for resistance to root rots Seed treatments Planting date (temperature) Cereal residue 3

4 Breeding for Resistance Two types of resistance Major gene Typically a single gene Provides a high level of resistance Minor gene Usually multiple genes Provides a lower level of resistance 4

5 Major (Single) Gene Resistance Photos: Kevin McPhee 5

6 Partial (Multiple Gene) Resistance 6

7 Breeding for Partial Resistance Difficulty of breeding for root rot resistance Genes confer partial resistance Unstable outside influences Environment Pathogen population Additive affects Combine genes through breeding 7

8 Aphanomyces resistance genes Hamon et al (2013); Desgroux et al. (2016) 8

9 Aphanomyces resistance genes Higher number of partial resistance genes in most resistant lines Most resistant lines More resistance genes Most susceptible lines Few to no resistance genes Desgroux et al. (2016) 9

10 Breeding for Aphanomyces Resistance 10 Desgroux et al. (2016)

11 Breeding for Root Rot Resistance Progress has been made breeding for resistance to root rot pathogens Resistance is not (and will likely not be) complete Understanding the pathogen populations is critical We continue to evaluate other management strategies 11

12 Root Rot Management An integrated approach Breeding for resistance to root rots Seed treatments Planting date (temperature) Cereal residue 12

13 Pathogen complex Pythium spp. Pulse Crop Root Rot Mefenoxam / metalaxyl is effective Several products available Rhizoctonia solani Fusarium spp. Aphanomyces euteiches 13

14 Rhizoctonia: Seed Treatment Efficacy Product ApronMaxx (no inoculum) Rate (fl oz/cwt) Chickpeas 2016 Plants / acre Chickpeas 2017 Lentils 2017 Peas No data 160, , ,962 ApronMaxx ,405 28,003 95, ,430 VibranceMaxx , , , ,897 VibranceMaxx + Mertect , , , ,630 Obvius , , , ,698 Rhizolex + Allegiance + Mertect No data 105, , ,362 Courtesy: Dr. Michael Wunsch Carrington REC

15 Rhizoctonia: Seed Treatment Efficacy Product ApronMaxx (no inoculum) Rate (fl oz/cwt) Chickpeas 2016 Yield (pounds / acre) Chickpeas 2017 Lentils 2017 Peas 2017 *(bushes/a) 5.0 No data ApronMaxx VibranceMaxx VibranceMaxx + Mertect Obvius Rhizolex + Allegiance + Mertect No data Courtesy: Dr. Michael Wunsch Carrington REC

16 Fusarium: Seed Treatment Efficacy 1. Fludioxonil: Maxim 4ST, Spirato 480ST, etc. 2. Evergol Energy (penflufen + prothioconazole) 3. VibranceMaxx (fludioxonil + sedaxane) 4. Obvius (pyraclostrobin + fluxapyroxad) All seed was treated with metalaxyl / mefenoxam Courtesy: Dr. Michael Wunsch Carrington REC

17 Fusarium: Seed Treatment Efficacy 1. Fludioxonil, 1.14 g ai/cwt (Maxim 4ST, Spirato 480ST, etc.) Improved plant population in 4 of 6 trials Improved yield in 3 of 6 trials 2. Evergol Energy, 1.0 fl oz/cwt (Metalaxyl, + Penflufen, + Prothioconazole) Improved plant population in 1 of 2 trials No yield increases were observed Courtesy: Dr. Michael Wunsch Carrington REC

18 Fusarium: Seed Treatment Efficacy 3. VibranceMaxx, 1.54 fl oz/cwt (Mefenoxam + Fludioxonil + Sedaxane) Improved plant populations in 3 of 4 trials Improved yield in 1 of 4 trials 4. Obvius, 4.6 fl oz/cwt (Metalaxyl + Pyraclostrobin + Fluxapyroxad) Improved plant populations in 2 of 3 trials Improved yield in 2 of 3 trials Courtesy: Dr. Michael Wunsch Carrington REC

19 Aphanomyces: Seed Treatment Efficacy Control of Aphanomyces with seed treatments is difficult: Aphanomyces root rot develops during vegetative growth and bloom The concentration of fungicide in the target tissues (tap root, epicotyl) is low Ethaboxam (Intego Solo): registered on lentils and chickpeas Best at the 0.3 fl oz/cwt rate Results have been mixed - inconsistent Courtesy: Dr. Michael Wunsch Carrington REC

20 Seed Treatment Efficacy A seed treatment is recommended A basic seed treatment may suffice under lower disease pressure Observed additional benefit from a combination of multiple active ingredients when disease pressure is high Results vary by environment If you have had success from a seed treatment in your fields, stick with it

21 Root Rot Management An integrated approach Breeding for resistance to root rots Seed treatments Planting date (temperature) Cereal residue 21

22 Aphanomyces - Response to planting date (field peas) Courtesy: Dr. Michael Wunsch Carrington REC Variety: DS Admiral (yellow-cotyledon type) Seeding rate: 300,000 pure live seeds/ac Direct-seeded into wheat stubble Seed treatment: Apron XL 0.16 fl oz/cwt + Apron Maxx RFC 1.5 fl oz/cwt + Rizolex 0.3 fl oz/cwt +/- Intego Solo 0.2 fl oz/cwt Pathogen isolation: Fusarium sp. from 16% of roots (early planting date), 8% (intermediate), 25% (late) Pathogen isolation: Aphanomyces sp. from 2% of roots (early planting date), 13% (intermediate), 0% (late)

23 Aphanomyces - Response to planting date (field peas) Courtesy: Dr. Michael Wunsch Carrington REC Variety: DS Admiral (yellow-cotyledon type) Seeding rate: 300,000 pure live seeds/ac Direct-seeded into wheat stubble Seed treatment: Apron XL 0.16 fl oz/cwt + Apron Maxx RFC 1.5 fl oz/cwt + Rizolex 0.3 fl oz/cwt +/- Intego Solo 0.2 fl oz/cwt Pathogen isolation: Fusarium sp. from 16% of roots (early planting date), 8% (intermediate), 25% (late) Pathogen isolation: Aphanomyces sp. from 2% of roots (early planting date), 13% (intermediate), 0% (late)

24 Fusarium - Response to planting date Courtesy: Dr. Michael Wunsch Carrington REC Variety: Abarth (yellow-cotyledon type) Seeding rate: 330,000 pure live seeds/ac Direct-seeded into wheat stubble Seed treatment: Gaucho 1.6 fl oz/cwt + Evergol Energy 1.0 fl oz/ac +/- (with or without) fluopyram 0.05 mg ai/seed Pathogen isolation: Fusarium sp. from 31% of roots (early planting date), 26% (intermediate), 26% (late) Pathogen isolation: Aphanomyces sp. from 0% of roots (early planting date), 0% (intermediate), 0% (late)

25 Fusarium - Response to planting date Courtesy: Dr. Michael Wunsch Carrington REC Variety: Abarth (yellow-cotyledon type) Seeding rate: 330,000 pure live seeds/ac Direct-seeded into wheat stubble Seed treatment: Gaucho 1.6 fl oz/cwt + Evergol Energy 1.0 fl oz/ac +/- (with or without) fluopyram 0.05 mg ai/seed Pathogen isolation: Fusarium sp. from 35% of roots (early planting date), 29% (intermediate), 28% (late) Pathogen isolation: Aphanomyces sp. from 0% of roots (early planting date), 0% (intermediate), 0% (late)

26 Fusarium Field Evaluations F. solani Non-inoculated F. avenaceum Photo: Jennifer Odom 26

27 Fusarium Field Evaluations Emergence (%) F. solani F. avenaceum Inoculum Odom et al, unpublished 27

28 Fusarium Field Evaluations Yield reduction (%) F. solani F. avenaceum Inoculum Odom et al, unpublished 28

29 Fusarium Field Evaluations Soil temperature At planting ( o F) Ave 2 wks postplanting ( o F) Damage caused by pathogens varies as a result of environmental conditions Extremely important for: o o Breeding for resistance Development of other management strategies 29

30 Root Rot Management An integrated approach Breeding for resistance to root rots Seed treatments Planting date (temperature) Cereal residue 30

31 Cereal Residue and Root Rot 5 Root rot severity (0-5) Ground cover (%) 31

32 Cereal Residue and Root Rot 5 Root rot severity (0-5) Residue depth (in) 32

33 Cereal Residue and Root Rot Number of isolates Fusarium recovered from Cereal Residue Straw Residue Duff Residue 33

34 Lentil Root Rot Severity Root development Enhanced plant growth Enhanced nutrient uptake Courtesy of Audrey Kalil - WREC Mapping credit: Charitha Hettiarachchi (NDSU)

35 Fusarium species from Lentil 40 Frequency (%)

36 Fusarium species from Lentil Field pea and lentil Fusarium root rot pathogens are very similar Both crops are also susceptible to Aphanomyces root rot These should not be considered rotations as far as root rot are considered Pea Cereal Lentil Cereal Pea This is a 2-year root rot rotation

37 Thank You Photo: Jennifer Odom 37