Integrated control of herbicide resistant Lolium rigidum in
extensive rainfed crops Jos M Montull, Andreu Taberner Slide 2
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
Slide 3 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 Slide 4 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 Slide 5 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. Slide 6 Material & methods Field
located in Calaf (Lleida) (NE Spain) 480mm average annual rainfall
Clay-loam soil Difficulty to control Lolium rigidum with herbicides
Three crops: Winter wheat, spring barley & spring field pea 5
herbicides per crop & untreated Slide 7 Material & methods
Crop HerbicideActive ingredient Rate (kg o l cp/ha) Aplication time
(respect the crop) Winter wheat Untreated0 AurosProsulfocarb 80%409
BBCH CTUClortolurn 50%211 BBCH AtlantisIodosulfuron 0,6%+
mesosulfuron 3%0,513BBCH BroadwayFlorasulam 2,28% +Pyroxulam
6,83%0,26513BBCH Caliban duoIodosulfurn 1%+propoxicarbazona
16,8%33013BBCH Spring barley Untreated0 CTUClortolurn 50%411BBCH
HerbaflexBeflubutamida 8,5%+Isoproturon 50%2,511BBCH AxialPinoxaden
10%0,613BBCH HussarIodosulfuron 5%0,213BBCH Splendor 40Tralkoxidim
40%122BBCH Spring pea Untreated0 AurosProsulfocarb 80%509BBCH
MutualImazamox 1,67%+Pendimetalina 25%309BBCH Kerb FloPropizamida
40%1,87513BBCH Fusilade MaxFluazifop-P 12,5%213BBCH Aramo
50Tepraloxidim 5%113BBCH Slide 8 Material & methods Aplication
due with an experimental sprayer pressurised with nitrogen Boom
with 4 Hardi ISO LD-110-02 nozzles 330l/ha of water delivery Slide
9 Results & discussion Lolium density at harvest in untreated
plots Slide 10 Results & discussion Slide 11 Results &
discussion Lolium Density at harvest Slide 12 Results &
discussion Slide 13 Conclusions 1. 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% Slide
14 Conclusions 5. 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.
