Page 1 Page 2 Page 3 Page 4 Page 5 Page 6 Page 7 Page 8 Page 9 Page 10 Page 11 Page 12 Page 13 Page 14 Page 15 Page 16 Page 17 Page 18 Page 19 Page 20 Page 21 Page 22 Page 23 Page 24 Page 25 Page 26 Page 27 Page 28 Page 29 Page 30 Page 31 Page 32 Page 33 Page 34 Page 35 Page 36 Page 37 Page 38 Page 39 Page 40 Page 41 Page 42 Page 43 Page 44 Page 45 Page 46 Page 47 Page 48 Page 49 Page 50 Page 51 Page 52 Page 53 Page 54 Page 55 Page 56 Page 57 Page 58 Page 59 Page 60 Page 61 Page 62 Page 63 Page 64 Page 65 Page 66 Page 67 Page 68 Page 69 Page 70 Page 71 Page 72 Page 73 Page 74 Page 75 Page 7625 IREC Farmers' Newsletter No. 195 ­ – Rice R&D 2016 Post-sowing Magister Trial H52-15, Cobram Magister @ 0.25, 0.5 and 1.0 L/ha was applied post-sowing and PFPE (alone or tank mixed with Stomp 440EC @ 3.4 L/ha. Gramoxone® @ 1.0 L/ha was added to all PFPE treatments to remove emerged weed seedlings. Post-sowing applications of Magister (+/- Stomp) proved less effective in controlling barnyard grass than PFPE applications. Sequencing Magister (post-sowing) followed by Stomp (PFPE +/- Magister) provided the highest barnyard grass control ratings and rice grain yields in this experiment. Rice injury ratings were acceptable with all treatments. PFPE applications of Magister were more injurious to rice than post-sowing treatments. These results demonstrated that the PFPE timing of Stomp plus Magister provides superior results to post-sowing application of Magister (alone or tank mixed with Stomp), confirming the current timing recommendations. Increased rates of Magister (achieved by splitting the dose between post- sowing and PFPE) offered improved residual barnyard grass control. Thus whilst an earlier timing of Stomp plus Magister might ensure that applications are not delayed by wet fields, optimum results remain more likely using current PFPE timings. Split applications of Magister plus Stomp Trial H10-15, Cobram This experiment examined the crop safety and efficacy of additional early post- emergence treatments of Magister or Stomp (or both) in order to extend the period of residual control of barnyard grass. Magister @ 0.5 L/ha and Stomp @ 3.4 L/ha (i.e. the recommended combination) were applied PFPE and again early post-emergence (EPE) in a variety of combinations. Gramoxone @ 1.0 L/ha was added to all PFPE treatments to remove emerged weed seedlings. No advantage was evident by splitting the dose of Magister plus Stomp. The full rate of the mixture was best when applied PFPE. Double treatment of Magister plus Stomp gave an advantage of prolonged residual barnyard grass control. EPE timing of Magister induced extra (transient) bleaching. Sequencing full rate Magister plus Stomp followed by Barnstorm® (i.e. a common commercial practice) gave the best barnyard grass control and highest rice grain yield. This experiment also demonstrated that the current recommended herbicide treatment of Magister plus Stomp (plus Gramoxone) applied PFPE was a robust and reliable recommendation. Repeat treatments did lift weed control ratings, however using an alternate post-emergence herbicide (Barnstorm) was better suited for use at the second timing (presumably) due to its superior efficacy against emerged barnyard grass. RIRDC Project PRJ-009923 Weed control in Australian rice More information Malcolm Taylor T: 03 5872 2892 M: 0427 722 892 E: [email protected] l Post-flush, pre-emergence is the optimum timing to apply residual treatments of Magister plus Stomp plus Gramoxone to control grass weeds in drill seeded rice crops. Table 1. Barnyard grass control ratings and Sherpa rice grain yields after treatment with residual herbicides, Cobram, 2015–16 season, Trial H10-15. Treatment and Application Barnyard grass control Grain yield application rate timing* (% control – (t/ha) (L product/ha) average of 3 ratings) Untreated control 0 1.46 Stomp 3.4 + Magister 0.5 PFPE 95.6 6.44 Stomp 3.4 f/b Magister 0.5 PFPE f/b EPE 88.4 5.93  Stomp 3.4 + Magister 0.5 f/b Stomp 3.4 + Magister PFPE f/b EPE 96.8 7.79  Stomp 3.4 + Magister f/b Barnstorm 1.0 PFPE f/b PW 96.8 7.94 LSD (P=0.05) 5.8 0.96 *PFPE –post-flush, pre-emergence; f/b – followed by; EPE – early post emergence; PW – permanent water l Figure 1. Barnyard grass control ratings (%) after treatment with Magister (alone or tank mixed with Stomp) herbicides, Cobram, 2015–16 season, Trial H52-15. 0 10 20 30 40 50 60 70 80 90 100 Magister 0.25 Magister 0.5 Magister 1.0 Magister 0.5 + Stomp 3.4 Magister 0.5 (2x) + Stomp 3.4 Control rating (%) Post sowing PFPE post sowing f/ Magister 0.25 Magister 0.5 Magister 1.0 Magister 0.5 + Stomp 3.4 Magister 0.5 (2x) + Stomp 3.4 Control rating (%) n Post sowing n PFPE n  post sowing f/b PFPE