WEED POTATO INTERFERENCE HAIRY NIGHTSHADEpotatoes.colostate.edu/wp-content/uploads/2018/03/Part-2... · 2018. 3. 6. · Potato Program of Distinction WEED –POTATO INTERFERENCE HAIRY

University of Idaho Competition and Interference Research Studies

▪ Determine hairy nightshade density needed to reduce Russet Burbank and Russet Norkotahtuber yields and quality: 0, 1, 2, 3, or 100/m row season-long• R. Norkotah is a short-season variety with determinate

growth and a canopy which does not always close across the rows

• R. Burbank is a full-canopied variety seemingly more competitive than R. Norkotah

WEED – POTATO INTERFERENCE

HAIRY NIGHTSHADE

Potato Program of Distinction

University of Idaho Competition and Interference Research Studies

▪ Determine period during potato growing season

when tuber yields will be reduced if hairy

nightshade is present – critical interference period

in R. Norkotah: 2/m row time of emergence, time of

removal


HAIRY NIGHTSHADE




HAIRY NIGHTSHADE

Hairy nightshade study: season-long competition of 0, 1, 2,

or 100 per m row* with two potato varieties at Aberdeen, ID

in 2004 and 2005.

Hairy nightshade

Potato Variety Biomass (g) Berries Stems Seeds/berry

----------------------- per sq m ------------------------------

R. Norkotah 1189 a 4,160 a 46 a 11 a

R. Burbank 379 b 625 b 15 b 7 b



HAIRY NIGHTSHADEEffect of hairy nightshade competition at 4 densities on tuber yield of two potato varieties at

Aberdeen, ID in 2004 and 2005.

Hairy nightshade Tuber yield

Variety density (per m row) U.S. No. 1 Total

--% reduction compared to no hairy nightshade present --

R. Norkotah 1 21 * 16 *

2 26 * 20 *

3 27 * 25 *

100 48 * 37 *

R. Burbank 1 6 5

2 10 * 9 *

3 11 * 9 *

100 21 * 19 *


HAIRY NIGHTSHADE

CRITICAL

INTERFERENCE PERIOD

5% OR GREATER

REDUCTION OF RUSSET

NORKOTAH U.S. NO 1’S

15

18

21

24

27

30

0 5 10 15 20 25 30 35 40

U.S

. N

o. 1 t

uber

yie

ld (

MT

ha

-1) days weed-free days weedy

Days after potato emergence (DAE)

Aberdeen R&E Center 2006 and 2007

Critical interference period:

Must be weed-free from

7 to 22 days after potato

emergence or >5% yield loss

Matrix Hairy and Eastern black nightshade (unless ALS herbicide resistance); No cutleaf control

Eptam Hairy, cutleaf, and Eastern black nightshade;

Outlook Hairy, cutleaf, and Eastern black nightshade

Chateau Hairy, cutleaf, and Eastern black nightshade


LABELS - NIGHTSHADE WEED CONTROL IN

POTATOES

Hairy nightshade

Common lambsquarters

Redroot pigweed

Green foxtail

Reality check…

There’s more than one species in a field!

H. nightshade R. pigweed C. lambsquarters Wild oat G. foxtail

Chateau

Outlook

Dual Magnum

Matrix

Prowl H2O

Sonalan

Metribuzin

Linex

Eptam


Which herbicide – which weed

C = control s = suppress


FYI BTW OKEY DOKEY


• Preemergence applied after hilling operation, sprinkler

incorporated, or chemigated

• Matrix and metribuzin are the only herbicides which

have foliar activity on broadleaves and can be applied

to emerged potatoes

• Also have preemergence burndown with glyphosate,

paraquat, carfentrazone

Plant Row close

3-4 weeks ~ 5 weeks

Hilling and Herbicide Application Timing

✓Hill just before or after potato emergence; hilling operation can control emerged weeds and create a “clean bed” ✓Apply herbicide(s) to the clean bed before potato and weed emergence✓Herbicide must be effective for ~6 weeks

Hill/Spray


INTEGRATED WEED MANAGEMENT IN POTATO

CROPPING SYSTEMS: HERBICIDES


TIMING AND SOLUBILITY

Timing hilling and herbicide application closer to potato emergence▪ Herbicides are in the weed germination zone longer into the season

Highly soluble herbicides may be leaching below the weed-seed

germination zone which in turn allows weed breaks▪ Matrix, metribuzin

Herbicides not as soluble may be more effective in sandy soils▪ Chateau, Prowl H2O, Lorox

Chemigation and sprinkler incorporation▪ Follow label instructions

▪ Coarse- to medium-textured soils use less than 0.5 inches especially if dry

H. nightshade

Chateau C

Outlook C

Dual Magnum s

Matrix C

Prowl H2O -

Sonalan s

Metribuzin -

Linex s+

Eptam C




H. nightshade R. pigweed

Chateau C -

Outlook C C

Dual Magnum s C

Matrix C C

Prowl H2O - C

Sonalan - C

Metribuzin - C

Linex s+ C

Eptam C C




H. nightshade R. pigweed C. lambsquarters

Chateau C - -

Outlook C C -

Dual Magnum s C -

Matrix C C -

Prowl H2O - C C

Sonalan - C s

Metribuzin - C C

Linex s+ C C

Eptam C C s




Wild oat G. foxtail

Chateau - -

Outlook C C

Dual Magnum C C

Matrix C C

Prowl H2O S C

Sonalan C C

Metribuzin s+ s

Linex s+ C

Eptam C C





Tank mix or else!

• Design mixtures dependent upon weed history in a given field

• “Stand alone” herbicide treatments not recommended

– Need tank mixtures for broad spectrum weed control

– Prevent or delay development of herbicide-resistant weed populations

▪ Use tank mixtures of herbicides with different mechanisms of action (MOA);

activity on same weed w/ different MOA

– Rotate herbicide MOA’s from year-to-year

• Use integrated weed management strategies

– Herbicides, mechanical, competitive crops, control in rotation crops


Chateau C -

Outlook C C

Dual Magnum s C

Matrix C C

Prowl H2O - C

Sonalan - C

Metribuzin - C

Linex s+ C

Eptam C C


2-way brews: H. nightshade/R. pigweed



Chateau 1 -

Outlook C C

Dual Magnum s C

Matrix C C

Prowl H2O - C

Sonalan - C

Metribuzin - C

Linex s+ C

Eptam C C



C = control s = suppress: 1 + 2 = 2-way mix


Chateau 1 -

Outlook C 2

Dual Magnum s 2

Matrix C 2

Prowl H2O - 2

Sonalan - 2

Metribuzin - 2

Linex s+ 2

Eptam C 2



C = control s = suppress: 1 + 2 = 2-way mix


Chateau C -

Outlook 1

Dual Magnum s

Matrix C 2

Prowl H2O - 2

Sonalan - 2

Metribuzin - 2

Linex s+ 2

Eptam C 2



C = control s = suppress : 1 + 2 = 2-way mix


Chateau C -

Outlook C 2

Dual Magnum s 2

Matrix 1

Prowl H2O - 2

Sonalan - 2

Metribuzin - 2

Linex s+ 2

Eptam C 2





Chateau C -

Outlook C 2

Dual Magnum s 2

Matrix C 2

Prowl H2O - 2

Sonalan - 2

Metribuzin - 2

Linex s+ 2

Eptam 1




H. nightshade C. lambsquarters

Chateau 1 -

Outlook 1 -

Dual Magnum s -

Matrix 1 -

Prowl H2O - 2

Sonalan -

Metribuzin - 2

Linex s+ 2

Eptam 1 s


2-way brews: H. nightshade/C. lambsquarters


Chateau

+

Prowl

1

2

Documents

WEED POTATO INTERFERENCE HAIRY NIGHTSHADEpotatoes.colostate.edu/wp-content/uploads/2018/03/Part-2... · 2018. 3. 6. · Potato Program of Distinction WEED –POTATO INTERFERENCE HAIRY