José Mª Montull, Andreu Taberner Integrated control of herbicide resistant Lolium rigidum in extensive rainfed crops 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 herbicideresistant L. Rigidum control in rainfed cereal cropping systems, integrating three different crops in rotation different herbicides approved for each crop. 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 Material & methods Spring pea Spring barley Winter wheat Crop Rate Aplication time (kg o l cp/ha) (respect the crop) Auros CTU Untreated Prosulfocarb 80% Clortolurón 50% 0 4 2 09 BBCH 11 BBCH Atlantis Iodosulfuron 0,6%+ mesosulfuron 3% 0,5 13BBCH Broadway Florasulam 2,28% +Pyroxulam 6,83% 0,265 13BBCH Caliban duo Iodosulfurón 1%+propoxicarbazona 16,8% 330 13BBCH Untreated 0 CTU Clortolurón 50% 4 11BBCH Herbaflex Beflubutamida 8,5%+Isoproturon 50% 2,5 11BBCH Axial Pinoxaden 10% 0,6 13BBCH Hussar Iodosulfuron 5% 0,2 13BBCH Splendor 40 Tralkoxidim 40% 1 22BBCH Untreated 0 Auros Prosulfocarb 80% 5 09BBCH Mutual Imazamox 1,67%+Pendimetalina 25% 3 09BBCH Kerb Flo Propizamida 40% 1,875 13BBCH Fusilade Max Fluazifop-P 12,5% 2 13BBCH Aramo 50 Tepraloxidim 5% 1 13BBCH Herbicide Active ingredient 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 Results & discussion Lolium density at harvest in untreated plots 100 A 90 80 Plantas/m2 70 60 50 40 B 30 20 B 10 0 Cebada Guisante Trigo Winter wheat Spring Pea Spring Barley Herbaflex Splendor CTU Axial Hussar Auros Mutual Kerb Flo Fusilade Max Aramo 50 CTU Caliban Duo Broadway Atlantis Auros Herbicide efficaccy Results & discussion 100% 90% 80% 70% 60% 50% 40% 30% 20% 10% 0% Results & discussion Lolium Density at harvest 100 90 a L. rigidum plants/m2 80 70 60 b bc 50 40 cd de de 30 20 10 0 efg ef fg fg fg fg g g fg fg fg g Results & discussion 7000 6000 c b c a bc bc a Yield (kg/ha) 4000 3000 b 1000 0 a a b 5000 2000 a b b b a a b 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% 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.