Rice Extension Agronomist Newsletter - July
Here is our first Agronomists Newsletter containing information we think is important to you. Note we have a number of events coming up which will be of special interest to you: R&D Update and Agronomists Technical Update – details of these and more are included below. We look forward to catching up with you all then.
Stories this month:
- Changes to the Sowing date recommendations for 2018/19
- Top 20% grower yields 2018
- Gross margin from a high yielding Sherpa crop 2017-18 season*
- Current Fixed Price Contracts
- Agixa™ with Rinskor™ active - excellent secondary option in drill sown rice
- Correct sampling procedure for testing herbicide resistance
- Nitrogen use efficiency in rice soils
- Summary of our responses to your requests at 2017 Agronomy meetings
- Invite to Agro day 23 August Griffith and Deniliquin
- Invite to R&D Update 7 & 8 August Yanco Agricultural Institute
- Send your new agronomists along to Rice 101 on 14 August RRAPL
- Rice Pre Season meetings 28, 29, 30 August
The newest variety guides can be found here.
Now is the time to do some budgets High yields are important to achieve high returns. The table below is from one of our case studies this year with good yields and 2017-18 rice prices. The importance of a good relationship with their agronomist has been a key to success from our case study growers.
Trials in the 2017/18 season demonstrated best control of barnyard grass was with Gramoxone®, Magister®, Stomp® mix applied post-flush, pre-emergence followed by Agixa applied post-emergence prior to permanent water.
Agixa contains Rinskor active and Barnstorm™ (cyhalofop-butyl) and is currently going through the registration process for use in drill sown rice for possible release in the 2019-20 season. The price will not be released until the product has been registered.
Agixa is one of two new chemicals containing Group I, Rinskor active. Ubeniq™, the other new chemical from Corteva AgriscienceTM Agriculture Division of DowDuPontTM, is now registered for aerial and dry broadcast crops and will be available for the coming season. Information about Ubeniq will be presented at the Agronomist Update on 23 August in Griffith and Deniliquin.
The advantage of Agixa is that it contains two modes of action (Group I and A) and controls broadleaf weeds, grasses. The control of barnyard grass was superior with the use of Agixa or Barnstorm after the foundation treatment 3-way mix (Table 1). Higher yields were achieved with better weed control (Figure 1). The value of Agixa is with its’ control of other weeds as well as barnyard grass.
Where possible, it is important to use the foundation herbicide application - Gramoxone, Magister, Stomp (three-way) mix before the secondary treatment. The three-way mix is the most economical and there are times when control will be satisfactory, so there will be no need for a secondary treatment. Gramoxone will take out already emerged weeds and Magister and Stomp, applied together, work more effectively than on their own as a residual. The three modes of action applied together are excellent for herbicide resistance management and provided 84% control when compared to the untreated plots in these trials (Table 1).
Table 1. Herbicide treatments and average barnyard grass percentage control ratings from five field trials in drill sown rice, Riverina, 2017–18. Note: 100% = no weeds.
Figure 1. Average rice yield from each different herbicide treatment at the Widgelli and Coleambally trial sites (located in commercial crops). Note the herbicide treatments labelled with the same letter are not statistically different.
72 % of dirty Dora seed tested was resistant to Londax and two populations were tested with suspected resistance to Taipan in 2017. There is currently no detected resistance to Group A herbicides in rice weeds, however, Barnstorm™ and Aura® are listed as High Risk for the development of herbicide resistance. Vigilance with herbicide resistance management is important.
It is important to detect herbicide resistance early in order to make decisions about future chemical and management options. If you suspect a weed population is resistant, then correct sampling procedure is important.
There are several herbicide resistance testing services available. The rice industry has been using Charles Sturt University for surveying weeds for resistance across the rice growing regions so they have developed protocols for assessment for rice weeds. Plant Science Consulting also offers a testing service.
When to collect: When the weed seed is mature.
How much seed: at least 1 cup full of clean individual weed seeds or an A4 envelope full of seed heads. The more seed, the better.
How to collect a sample:
- Walk across the entire area suspected of resistance and cover the area on several transects e.g. follow a W shape.
- Collect a similar number of seeds from each plant in order to avoid bias in the sample e.g. collect samples every 15-20 paces.
- The seed must be completely dry when you send it. Air dry for three to four days to reduce the risk of seed rotting in transit.
- Place in a sealed bag with an identification slip.
The Charles Sturt University Seed Sample Form and can be found here.
Information about Plant Science Consulting testing can be found here
Why is it more efficient to drill nitrogen fertiliser underneath the soil surface in aerial sown rice?
Why is it most efficient to apply urea prior to permanent water?
Even in flooded conditions, the very top layer of soil and around the rice roots will be aerobic. So some ammonium will still nitrify (to nitrate) and be lost through denitrification and leaching.
If urea is applied prior to flushing, there are many ways nitrogen can be lost once the soil dries out and is then re-flooded. Especially in the early stages, when there are no plants to take up available nitrogen.
How is efficient is applying urea at different times?
Mid-season topdressing has lower efficiency than other application methods but varies depending on crop growth stage.
These nitrogen use efficiencies are estimates and can change significantly, there have been no experiments directly comparing all treatments.
Note: At 70% efficiency, 70 kg/ha will go into the plant if you apply 100 kg/ha nitrogen.
Barber TB, et al. (2013) Arkansas Rice Production Handbook, University of Arkansas.
Dunn BW, Dunn TS & Orchard BA (2016) Nitrogen rate and timing effects on growth and yield of drill-sown rice, Crop and pasture Science 67, 1149-1157
Linquist BA, et al. (2009) Assessing the necessity of surface applied preplant nitrogen fertilizer in rice systems. Agronomy Journal 101, 906–915.
Russell CA, et al. (2006) Soil tests to predict optimum fertilizer nitrogen rate for rice. Field Crops Research 97, 286–301.
At the last update we asked for your feedback on our activities and communications. As a result of this feedback we have made a number of changes to the way we work in particular we have:
- You asked for more technical information and to receive information before growers. - We are sending out this newsletter and two more during the year for agronomists only and holding the Agronomist Update earlier, so you get new information before growers prior to the start of the season.
- You asked for industry data. - SunRice Grower Services will be presenting more data on benchmarking growers at the Agronomist Update.
- You asked for information on varieties and water savings. - Variety agronomy and water saving information will be presented at the Agronomists Update.
- You asked for a variety guide for each variety. - These can be found here.
- You asked for an improved website. - A new website was launched in December with a new layout and easier access. Find it here at https://riceextension.org.au
This update will provide agronomists with the detail needed to best serve their rice-growing clients throughout the season:
- How to get the best out of the new rice herbicide
- Variety specific agronomy packages update
- Skills required in understanding your clients
- Controlling weeds in delayed permanent water
- Water use
- Rice whole grain yield
- Yields, contracts, world markets
Save the date –
Breakfast at Griffith - 7:30 to 10 am 23 August
Afternoon tea at Deniliquin – 2:00 to 4:00 pm 23 August Downstairs Meeting Room at SunRice Deniliquin Mill
Anna Jewell from SunRice Grower Services has organised a tour at Deni Mill prior to the Technical Update for Murray Valley agronomists.
Please lock this one in your diary. More information will be sent to you soon.
AgriFutures and Rice Extension are inviting rice researchers along to present their up to date research results.
Researchers, advisors, agronomists and interested growers will have the opportunity to share knowledge and ideas, network and collaborate.
Please register if you would like to come along to hear more about the details and technicalities of current rice R&D projects. It is suggested that agronomists would find the morning and early afternoon sessions of Tuesday 7th will cover off the agronomy topics.
For more information and to register:
Do you have a new agronomist starting this season or new grower in your area?
If you do please sign them up for this course at Jerilderie.
The free workshop features presentations from industry experts on the rice cropping - from planning, layouts, planting, weed control and nutrition for high yields to optimising quality, varieties, pricing and gross margins.
It is a ‘must do’ for understanding rice production prior to the season start. Call us now to claim a place – more info will be coming out shortly.
- Wakool and, Deniliquin - 28 August,
- Finley and Coleambally - 29 August
- Griffith and Whitton - 30 August
Lock this one in your diary as the event you need to attend to hear all the latest rice growing information prior to sowing:
- variety premiums, delivery points and production requirements
- new herbicides
- achieving the best yields with the best agronomy for each variety
- information from growers achieving high yields and best quality