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 7618 IREC Farmers' Newsletter No. 195 ­ – Rice R&D 2016 Seedling vigour An important aspect of rice agronomy is seedling vigour. Two experiments were conducted in a constant temperature room measuring the shoot and root growth of 13 current and future varieties. The same varieties were also tested in two field experiments, one on the heavy self- mulching clay soil at Leeton Field Station and the other on the red-brown earth at Yanco Agricultural Institute. Rows of seeds for each variety were planted at a depth of 25 mm and each day the number of seeds emerged was counted. Varieties were compared on the time it took the seedlings to emerge from the soil and the percentage of seed established. We currently only have one season of results, so recommendations are difficult to provide, but across laboratory and field studies Reiziq showed the best seedling vigour of all varieties and also the longest coleoptile length. When measuring seedling vigour, the environment the seed came from can have a large impact on the vigour of the seedling. To account for this environmental variability, seed was collected from the Yanco experiment and will be used in next season’s experiments, to ensure we are only measuring genetic variability in seedling vigour. Future research As further research is conducted over coming seasons the value of the information from this project will increase as will the robustness of the recommendations. Phenology of current and new varieties will continue to be assessed and sowing date recommendations refined when required. Research into varietal differences in seed establishment percentage and establishment vigour will be continued so that sowing rate recommendations can be fine-tuned for all current varieties and provided for new varieties as they are released. In future, as new varieties are released to the rice industry, there will be a good source of agronomic data from research undertaken in this project that will be used to develop a variety management package to be released with each new variety. RIRDC Project PRJ-009790 Rice variety nitrogen & agronomic management Acknowledgements This research was funded by the Rural Industries Research and Development Corporation and NSW Department of Primary Industries. Further information Brian Dunn Research Agronomist T: 02 6951 2621 E: [email protected] l Figure 1. Time of sowing or first flush, panicle initiation, microspore and flowering for each variety in six experiments, at commercial nitrogen rates. The green box illustrates the preferred time for microspore to occur to maximise probability of warm minimum temperatures. 01-Oct-15 16-Oct-15 31-Oct-15 15-Nov-15 30-Nov-15 15-Dec-15 30-Dec-15 14-Jan-16 29-Jan-16 13-Feb-16 28-Feb-16 Reiziq Sherpa Langi Topaz Doongara YRL 127 Topaz Langi YRL127 Doongara Reiziq Sherpa Koshi Opus Topaz Kyeema Reiziq Sherpa Opus Koshi Reiziq Sherpa YRM70 Jarrah Reiziq Sherpa YRK5 YRM70 Date sown PI Microspore Flowering Yanco drill Murrami aerial Mayrung aerial Yenda drill Leeton drill Jerilderie drill ◆ Date sown n PI ▲ Microscope X Flowering l Aerial photo of drill sown rice agronomy experiments at Yanco Agricultural Institute, February 2015.