# Presentation: 005201

## Identification of new sources of partial resistance to oat crown rust

- Marty Carson, USDA Cereal Disease Lab, St. Paul, MN

## Slide 2

## Oat Crown Rust: the Pathosystem from Hell

- 90+ Pc genes described; virulence to all of them
- Sexually recombining pathogen
- Positive virulence associations
- No apparent cost to complex virulence
- Resistant cultivars have a 3-5 yr lifespan

## Slide 4

## Insanity: continuing to do the same thing, but expecting different results

## ‘Slow Rusting’ or Partial Resistance to Oat Crown Rust

- Portage, Minhafer, Lodi (Heagle & Moore, 1970)
- Red Rustproof (Luke et al, 1972)
- MN841801, MN841810, MN841804, etc. (Leonard, 2002)

## Problem: Identification of partial, non-specific resistance in the presence of race-specific resistance genes when corresponding virulence in the pathogen population is at a low frequency (Parlevliet, 1983)

## Slide 8

## Slide 9

| Entry | 2005 Buckthorn Nursery |  | 2005 Virulent Inoculum |  |
| --- | --- | --- | --- | --- |
|  | 7/5 | 7/13 | 7/11 | 7/18 |
| CDC Boyer | 4S | 45S | 10S | 25S |
| MN841801 | 2MR/MS | 22MR/MS | 7S | 15MR |
| Pc68 | Trace | 7S | 55S | dead |
| GS7 | 7S | 50S | 7S | 22S |
| IA 98822-2 | 5S | 50S | 20S | 32S |
| CI4706 | 0 | 10S | Trace | 1S |
| CI5562 | 4S | 50S | 10S | mature |
| CI5632 | 10S | 60S | 40S | 40S |
| CI7035 | 0 | 20S | 5S | 10S |
| CI8220 | 10S | 80S | 25S | 45S |
| CI8261 | 5S | 50S | 25S | mature |
| CI8262 | 4S | 55S | 15S | 30S |
| CI8429 | Trace | 30MR/MS | 5MS | 10S |
| CI9244 | 15S | 80S | 50S | dead |
| CI9248 | 1S | 10MR/MS | 5MS | 5MR |
| CI9416 | 4S | 40S | 15S | 30S |
| PI189733 | 7S | 30MS/MR | 25MS | 30MR/MS |
| PI260616 | 4S | 30S | 10MS | 10MS |
| PI263412 | Trace | 20S | 1MS | 5S |
| PI266884 | 0 | 7S | 1MR | 3MR |
| PI266887 | Trace | 15S | 2S | 7S |

## Slide 10

| Entry | 2005 Buckthorn Nursery |  | 2005 Virulent Inoculum |  |
| --- | --- | --- | --- | --- |
|  | 7/5 | 7/13 | 7/11 | 7/18 |
| CDC Boyer | 4S | 45S | 10S | 25S |
| MN841801 | 2MR/MS | 22MR/MS | 7S | 15MR |
| Pc68 | Trace | 7S | 55S | dead |
| GS7 | 7S | 50S | 7S | 22S |
| IA 98822-2 | 5S | 50S | 20S | 32S |
| CI4706 | 0 | 10S | Trace | 1S |
| CI5562 | 4S | 50S | 10S | mature |
| CI5632 | 10S | 60S | 40S | 40S |
| CI7035 | 0 | 20S | 5S | 10S |
| CI8220 | 10S | 80S | 25S | 45S |
| CI8261 | 5S | 50S | 25S | mature |
| CI8262 | 4S | 55S | 15S | 30S |
| CI8429 | Trace | 30MR/MS | 5MS | 10S |
| CI9244 | 15S | 80S | 50S | dead |
| CI9248 | 1S | 10MR/MS | 5MS | 5MR |
| CI9416 | 4S | 40S | 15S | 30S |
| PI189733 | 7S | 30MS/MR | 25MS | 30MR/MS |
| PI260616 | 4S | 30S | 10MS | 10MS |
| PI263412 | Trace | 20S | 1MS | 5S |
| PI266884 | 0 | 7S | 1MR | 3MR |
| PI266887 | Trace | 15S | 2S | 7S |

## Slide 11

| Entry | 2005 Buckthorn Nursery |  | 2005 Virulent Inoculum |  |
| --- | --- | --- | --- | --- |
|  | 7/5 | 7/13 | 7/11 | 7/18 |
| CDC Boyer | 4S | 45S | 10S | 25S |
| MN841801 | 2MR/MS | 22MR/MS | 7S | 15MR |
| Pc68 | Trace | 7S | 55S | dead |
| GS7 | 7S | 50S | 7S | 22S |
| IA 98822-2 | 5S | 50S | 20S | 32S |
| CI4706 | 0 | 10S | Trace | 1S |
| CI5562 | 4S | 50S | 10S | mature |
| CI5632 | 10S | 60S | 40S | 40S |
| CI7035 | 0 | 20S | 5S | 10S |
| CI8220 | 10S | 80S | 25S | 45S |
| CI8261 | 5S | 50S | 25S | mature |
| CI8262 | 4S | 55S | 15S | 30S |
| CI8429 | Trace | 30MR/MS | 5MS | 10S |
| CI9244 | 15S | 80S | 50S | dead |
| CI9248 | 1S | 10MR/MS | 5MS | 5MR |
| CI9416 | 4S | 40S | 15S | 30S |
| PI189733 | 7S | 30MS/MR | 25MS | 30MR/MS |
| PI260616 | 4S | 30S | 10MS | 10MS |
| PI263412 | Trace | 20S | 1MS | 5S |
| PI266884 | 0 | 7S | 1MR | 3MR |
| PI266887 | Trace | 15S | 2S | 7S |

## Slide 12

| Entry | 2005 Buckthorn Nursery |  | 2005 Virulent Inoculum |  |
| --- | --- | --- | --- | --- |
|  | 7/5 | 7/13 | 7/11 | 7/18 |
| CDC Boyer | 4S | 45S | 10S | 25S |
| MN841801 | 2MR/MS | 22MR/MS | 7S | 15MR |
| Pc68 | Trace | 7S | 55S | dead |
| GS7 | 7S | 50S | 7S | 22S |
| IA 98822-2 | 5S | 50S | 20S | 32S |
| CI4706 | 0 | 10S | Trace | 1S |
| CI5562 | 4S | 50S | 10S | mature |
| CI5632 | 10S | 60S | 40S | 40S |
| CI7035 | 0 | 20S | 5S | 10S |
| CI8220 | 10S | 80S | 25S | 45S |
| CI8261 | 5S | 50S | 25S | mature |
| CI8262 | 4S | 55S | 15S | 30S |
| CI8429 | Trace | 30MR/MS | 5MS | 10S |
| CI9244 | 15S | 80S | 50S | dead |
| CI9248 | 1S | 10MR/MS | 5MS | 5MR |
| CI9416 | 4S | 40S | 15S | 30S |
| PI189733 | 7S | 30MS/MR | 25MS | 30MR/MS |
| PI260616 | 4S | 30S | 10MS | 10MS |
| PI263412 | Trace | 20S | 1MS | 5S |
| PI266884 | 0 | 7S | 1MR | 3MR |
| PI266887 | Trace | 15S | 2S | 7S |

## Slide 13

| Entry | 2005 Buckthorn Nursery |  | 2005 Virulent Inoculum |  |
| --- | --- | --- | --- | --- |
|  | 7/5 | 7/13 | 7/11 | 7/18 |
| CDC Boyer | 4S | 45S | 10S | 25S |
| MN841801 | 2MR/MS | 22MR/MS | 7S | 15MR |
| Pc68 | Trace | 7S | 55S | dead |
| GS7 | 7S | 50S | 7S | 22S |
| IA 98822-2 | 5S | 50S | 20S | 32S |
| CI4706 | 0 | 10S | Trace | 1S |
| CI5562 | 4S | 50S | 10S | mature |
| CI5632 | 10S | 60S | 40S | 40S |
| CI7035 | 0 | 20S | 5S | 10S |
| CI8220 | 10S | 80S | 25S | 45S |
| CI8261 | 5S | 50S | 25S | mature |
| CI8262 | 4S | 55S | 15S | 30S |
| CI8429 | Trace | 30MR/MS | 5MS | 10S |
| CI9244 | 15S | 80S | 50S | dead |
| CI9248 | 1S | 10MR/MS | 5MS | 5MR |
| CI9416 | 4S | 40S | 15S | 30S |
| PI189733 | 7S | 30MS/MR | 25MS | 30MR/MS |
| PI260616 | 4S | 30S | 10MS | 10MS |
| PI263412 | Trace | 20S | 1MS | 5S |
| PI266884 | 0 | 7S | 1MR | 3MR |
| PI266887 | Trace | 15S | 2S | 7S |

## Slide 14

| Entry | 2006 Buckthorn Nursery |  | 2006 Virulent Inoculum (1-9) |  |
| --- | --- | --- | --- | --- |
|  | 6/28 | 7/5 | 7/14 | 7/23 |
| CDC Boyer | 5S | 30S | 6.5 | 4.5 |
| MN841801 | 5MS | 20MR/MS | 7.5 | 5.5 |
| Pc68 | 5S | 30S | 6.0 | 1.5 |
| Starter | 30S | 80S | 3.0 | 1.0 |
| CI1712 | 3MS | 15MR/MS | 8.0 | 7.0 |
| CI1965 | 4MS | 25MS | 6.0 | 3.5 |
| CI4736 | 3S | 10MR/MS | 7.5 | 3.5 |
| CI6991 | 5MS/S | 20S | 6.5 | 3.0 |
| CI8000 | 3MS | 15MS | 7.5 | 6.5 |
| CI8357 | 5S | 20MS | 8.0 | 4.5 |
| CI8358 | 40S | 65S | 6.0 | 2.5 |
| CI8432 | 5S | 15MS | 6.5 | 3.0 |
| CI9247 | 0R | 4MR | 8.0 | 7.0 |

## Slide 15

| Entry | 2006 Buckthorn Nursery |  | 2006 Virulent Inoculum (1-9) |  |
| --- | --- | --- | --- | --- |
|  | 6/28 | 7/5 | 7/14 | 7/23 |
| CDC Boyer | 5S | 30S | 6.5 | 4.5 |
| MN841801 | 5MS | 20MR/MS | 7.5 | 5.5 |
| Pc68 | 5S | 30S | 6.0 | 1.5 |
| Starter | 30S | 80S | 3.0 | 1.0 |
| CI1712 | 3MS | 15MR/MS | 8.0 | 7.0 |
| CI1965 | 4MS | 25MS | 6.0 | 3.5 |
| CI4736 | 3S | 10MR/MS | 7.5 | 3.5 |
| CI6991 | 5MS/S | 20S | 6.5 | 3.0 |
| CI8000 | 3MS | 15MS | 7.5 | 6.5 |
| CI8357 | 5S | 20MS | 8.0 | 4.5 |
| CI8358 | 40S | 65S | 6.0 | 2.5 |
| CI8432 | 5S | 15MS | 6.5 | 3.0 |
| CI9247 | 0R | 4MR | 8.0 | 7.0 |

## Slide 16

| Entry | 2006 Buckthorn Nursery |  | 2006 Virulent Inoculum (1-9) |  |
| --- | --- | --- | --- | --- |
|  | 6/28 | 7/5 | 7/14 | 7/23 |
| CDC Boyer | 5S | 30S | 6.5 | 4.5 |
| MN841801 | 5MS | 20MR/MS | 7.5 | 5.5 |
| Pc68 | 5S | 30S | 6.0 | 1.5 |
| Starter | 30S | 80S | 3.0 | 1.0 |
| CI1712 | 3MS | 15MR/MS | 8.0 | 7.0 |
| CI1965 | 4MS | 25MS | 6.0 | 3.5 |
| CI4736 | 3S | 10MR/MS | 7.5 | 3.5 |
| CI6991 | 5MS/S | 20S | 6.5 | 3.0 |
| CI8000 | 3MS | 15MS | 7.5 | 6.5 |
| CI8357 | 5S | 20MS | 8.0 | 4.5 |
| CI8358 | 40S | 65S | 6.0 | 2.5 |
| CI8432 | 5S | 15MS | 6.5 | 3.0 |
| CI9247 | 0R | 4MR | 8.0 | 7.0 |

## Slide 17

| Entry | 2006 Buckthorn Nursery |  | 2006 Virulent Inoculum (1-9) |  |
| --- | --- | --- | --- | --- |
|  | 6/28 | 7/5 | 7/14 | 7/23 |
| CDC Boyer | 5S | 30S | 6.5 | 4.5 |
| MN841801 | 5MS | 20MR/MS | 7.5 | 5.5 |
| Pc68 | 5S | 30S | 6.0 | 1.5 |
| Starter | 30S | 80S | 3.0 | 1.0 |
| CI1712 | 3MS | 15MR/MS | 8.0 | 7.0 |
| CI1965 | 4MS | 25MS | 6.0 | 3.5 |
| CI4736 | 3S | 10MR/MS | 7.5 | 3.5 |
| CI6991 | 5MS/S | 20S | 6.5 | 3.0 |
| CI8000 | 3MS | 15MS | 7.5 | 6.5 |
| CI8357 | 5S | 20MS | 8.0 | 4.5 |
| CI8358 | 40S | 65S | 6.0 | 2.5 |
| CI8432 | 5S | 15MS | 6.5 | 3.0 |
| CI9247 | 0R | 4MR | 8.0 | 7.0 |

## What are these sources of Partial Resistance?

- CI1712 (Siberian sel.; Canada)
- CI4706 (La Prevision, Argentina)
- CI7035 (Buck sel., Argentina)
- CI8000 (Ark. 2-51-20)
- CI8357 (Fla. 65Q1896-97)
- CI8429 (66Ab599, Fla.)
- CI9247 (MN756515)
- CI9248 (MN756555)

- PI189733 (Nacional 190, Ecuador)
- PI260616 (Amarela 5282 B 32, Brazil)
- PI263412 (Red Algerian #31, Algeria)
- PI266884 (Santa Maria, Portugal)
- PI266887 (Santa Rosa, Portugal)

## Slide 19

## Slide 20

## Barriers to Using Partial Resistance in Oat Breeding

- Complex inheritance
- Poor Agronomics of Sources
- BYDV Susceptibility
- Associated with Late Maturity (Diaz-Lago et al, 2002)

## Slide 22