Integrated control of herbicide resistant Lolium rigidum in extensive

rainfed crops

José Mª Montull, Andreu Taberner

Introduction

Rainfed crops in Spain take around 9700000ha

Yields fluctuate between 1-5 tm/ha of barley

There are few available crops for rotation & farmers unknown the return on alternative crops

Introduction

In the short term, monocropping seems to have more return

In the long term, rotations can have the same or more return:◦Increase of yields◦Decreases pests◦Decresase the cost on plant protection

Directive 2009/128/EC establishes the requirement of IPM

Introduction Alternative crops

There are two groups of alternative crops: ◦Oilseed crops◦Pulse crops

Broadleaf crops can facilitate grass weeds managing:◦Late crop sowing◦Use herbicides with different modes of action◦Use of “strong” ACCase inhibitors for control

NTSR

Introduction Objective

The main objective of this paper is to study different alternatives for herbicide-resistant L. Rigidum control in rainfed cereal cropping systems, integrating three different crops in rotation different herbicides approved for each crop.

Material & methodsField located in Calaf (Lleida) (NE Spain)480mm average annual rainfall Clay-loam soilDifficulty to control Lolium rigidum with

herbicidesThree crops: Winter wheat, spring barley

& spring field pea5 herbicides per crop & untreated

Material & methodsCrop Herbicide Active ingredient Rate

(kg o l cp/ha)Aplication time(respect the crop)

Winter

wheat

Untreated 0Auros Prosulfocarb 80% 4 09 BBCHCTU Clortolurón 50% 2 11 BBCH

Atlantis Iodosulfuron 0,6%+ mesosulfuron 3% 0,5 13BBCHBroadway Florasulam 2,28% +Pyroxulam 6,83% 0,265 13BBCH

Caliban duo Iodosulfurón 1%+propoxicarbazona 16,8% 330 13BBCH

Spring

barley

Untreated 0CTU Clortolurón 50% 4 11BBCH

Herbaflex Beflubutamida 8,5%+Isoproturon 50% 2,5 11BBCHAxial Pinoxaden 10% 0,6 13BBCH

Hussar Iodosulfuron 5% 0,2 13BBCHSplendor 40 Tralkoxidim 40% 1 22BBCH

Spring

pea

Untreated 0Auros Prosulfocarb 80% 5 09BBCH

Mutual Imazamox 1,67%+Pendimetalina 25% 3 09BBCHKerb Flo Propizamida 40% 1,875 13BBCH

Fusilade Max Fluazifop-P 12,5% 2 13BBCHAramo 50 Tepraloxidim 5% 1 13BBCH

Material & methodsAplication due with an experimental

sprayer pressurised with nitrogenBoom with 4 Hardi ISO LD-110-02 nozzles330l/ha of water delivery

Results & discussionLolium density at harvest in untreated plots

Cebada Guisante Trigo0

10

20

30

40

50

60

70

80

90

100

B

B

A

Plan

tas/

m2

Results & discussion

Auro

s

Atla

ntis

Broa

dway

Calib

an D

uo CTU

Aram

o 50

Fusil

ade

Max

Kerb

Flo

Mutu

al

Auro

s

Huss

ar

Axia

l

CTU

Sple

ndor

Herb

aflex

Winter wheat Spring Pea Spring Barley

0%

10%

20%

30%

40%

50%

60%

70%

80%

90%

100%

Her

bici

de e

ffic

accy

Results & discussionLolium Density at harvest

Testig

o (Tri

go)

Auros

(Trig

o)

Atlant

is (trig

o)

Broad

way (tri

go)

Calib

an du

o (trig

o)

CTU (tr

igo)

Testig

o (gu

isante

)

Aramo 5

0 (gui

sante)

Fusila

de max

(guis

ante)

Kerb

flo (g

uisan

te)

Mutual

(guisa

nte)

Auros

(guis

ante)

Testig

o (Ceb

ada)

Hussar

(Cebada

Axial

(Ceb

ada)

CTU (c

ebada)

Splen

dor (C

ebad

a)

Herbafl

ex (C

ebada

)0

10

20

30

40

50

60

70

80

90

100a

bbc

cdde

efg

de

effg fg

g g

fgfg fg fg fg

g

L. r

igid

um p

lant

s/m

2

Results & discussion

Testig

o (Tri

go)

Auros

(Trig

o)

Atlant

is (trig

o)

Broad

way (tri

go)

Calib

an du

o (trig

o)

CTU (tr

igo)

Testig

o (gu

isante

)

Aramo 5

0 (gui

sante)

Fusila

de max

(guis

ante)

Kerb

flo (g

uisant

e)

Mutual (

guisan

te)

Auros

(guis

ante)

Testig

o (Ceb

ada)

Hussar

(Cebada

Axial

(Ceb

ada)

CTU (c

ebada

)

Splen

dor (C

ebad

a)

Herbafl

ex (Ce

bada

)0

1000

2000

3000

4000

5000

6000

7000

c cb

bc bca

b b b ba a

a a ab

ab

Yiel

d (k

g/ha

)

Conclusions1. The effect of sowing in late January have been enough to

avoid applying herbicides against L. rigidum in barley crop

2. In this test, low efficacy has been achieved with ALS and ACCase inhibitors due resistance to these groups of herbicides

3. Auros and Kerb efficacy was conditioned by the drought at winter in the application time

4. Only Mutual and Auros in spring pea, have been achieved efficaccy up to 90%

Conclusions5. 90 plants/m2 of L. rigidum in winter wheat justify a

treatment for control it

6. 15 plants/m2 of L. rigidum in spring barley not justify a herbicide treatment

7. 10 plants/m2 of L. rigidum in spring pea justify a treatment for controlling it

8. If this field, infested by a Lolium herbicide resistant biotype, it was not economically justified a treatment with an herbicide which the weed has developed resistance. In this case, the best solution has been the crop change.