Life Impact The University of Adelaide

Integrated Management of Brome

Christopher Preston, Sam Kleemann and Gurjeet Gill

School of Agriculture, Food & Wine, University of Adelaide

Life Impact The University of Adelaide

The problem

• Resistance• Later emergence• Competitive and impacts on yield• Sheds seed prior to harvest

Life Impact The University of Adelaide

Herbicide Resistant Brome Grass Survey 2012

Herbicides North Mallee South MalleeSamples with resistance (%)

Verdict 0 0Atlantis 64 26Crusader 75 24Glyphosate 0 0

Life Impact The University of Adelaide

Change in behaviour of brome grass

0 30 60 90 120 1500

20

40

60

80

100

CropFence-line

Apr May Jun Jul AugMonth

Ger

min

atio

n (%

)

Life Impact The University of Adelaide

Life Impact The University of Adelaide

Intervix (1.8 L ha-1) resistant brome from SA Mallee

Life Impact The University of Adelaide

Long term brome management -Balaklava

Life Impact The University of Adelaide

Management strategies usedCropping phase

Herbicide strategy (1 & 2)

HS1 HS2Lupins Simazine pre

Haloxyfop postSimazine preHaloxyfop postParaquat crop-top

TT-canola Atrazine preAtrazine plus haloxyfop post

Propyzamide preAtrazine plus haloxyfop postGlyphosate crop-top

Wheat Trifluralin preIntervix post

Sakura plus avadex preGlyphosate crop-top

Barley Trifluralin plus metribuzin pre

Trifluralin preIntervix post

Life Impact The University of Adelaide

Effect of management strategies on brome seed bank

Life Impact The University of Adelaide

Effect of management strategies on brome populations in 2015Cropping phase HS Brome grass

density(plants/m2)

Brome grass seed production

(paniclesm-2)

(seedsm-2)

2014 2015 4 WBS

5 WAS

18 WAS

Wheat Barley 1 1 2 17 3 522 36 42 45 1 9

TT-canola Wheat 1 5 7 10 0 02 2 3 11 27 626

Barley Lupins 1 14 28 30 1 22 1 5 6 0 0

Lupins TT-canola 1 12 4 5 0 02 7 13 4 0 0

LSD (P=0.05)† 3.4 1.4 2.5 0.8 23.1

Life Impact The University of Adelaide

Conclusions

• Seed bank persistence of brome is high (25%), so more than 1 year of control is required

• Effective pre- and post-emergent herbicides followed by crop topping in lupins and canola reduced brome seed numbers to low levels

• Complete reliance on pre-emergent herbicides in cereals allowed seed numbers to increase

• Resistance to Intervix is not far away. • Two year strategy to drive down numbers. Use

Intervix in the cereal crop with other herbicides and crop topping in break crop.