Arkansas Rice Update 6-4-21

by Jarrod Hardke, Rice Extension Agronomist - June 4, 2021

Arkansas Rice Update 2021-12

June 4, 2021

Jarrod Hardke, Nick Bateman, Gus Lorenz, Ben Thrash, Trent Roberts, Yeshi Wamishe, and Scott Stiles

“What goes up, must come down, spinning wheels, spinning round.”

Correction, Rain Not So Good

Jarrod Hardke

If we weren’t crazy, we would all go insane.  From this weather that is.  It’s déjà vu all over again, with a similar pattern right now to what we experienced in 2020.  The coming stretch of rain isn’t from a tropical storm like it was last year, but it’s a rainy stretch nonetheless.

The task at hand, of course, is trying to get rice to flood that’s starting to get some age on it.  There are a million different scenarios we’re dealing with on that end, with no easy answers.  We’re in major need of some warmer temps and sunlight to get other pale, struggling rice over the hump.

The positive side is that if mild conditions continue throughout the summer, we have very good yield potential.  A number of recent years have shown us that, we just need to do the best crop management we can.  There’s a lot of material in this update that we hope makes that easier.  Let us know if we can help.

Rice Water Weevil Activity is Starting to Increase

Nick Bateman, Gus Lorenz, and Ben Thrash

Our rice water weevil (RWW) plots went to flood 2 weeks ago, and RWW activity has been extremely low.  These plots are located in Stuttgart, where RWW pressure is low to moderate in most years.  Looking at these plots this week, the weevil scarring has increased quite a bit, with a lot of RWW adults present in the field.  We have also observed this for multiple fields around RREC that we have been monitoring for the past few weeks.  It is still early to make a prediction on how bad RWW will be this year, but this has been the trend we have observed over past 2 to 3 years.

While this scarring from adult weevil feeding is usually superficial and doesn’t cause yield loss, this is a sign that adults are present and active in the field.  Unfortunately, with the weather conditions we have had, planting has been delayed along with flood timing.  Based on planting date studies, we have observed much higher RWW pressure in rice planted after mid-May.

The bulk of rice planted in Arkansas is either treated with NipsIt or CruiserMaxx seed treatment, which are excellent on grape colaspis.  However, efficacy of these products on RWW decreases 28-35 days after planting.  Although RWW pressure is higher for later planted rice, these plantings typically experience rapid growth allowing us to flood within 3 weeks of planting.  In these situations, we still get sufficient control of RWW with NipsIt or CruiserMaxx.  If rice has been treated with Dermacor or Fortenza, it will still have protection from RWW at least 60 days after planting.  Also, it is important to note that NipsIt and Cruiser within the 28-35 days after planting will reduce scarring observed.  However, Dermacor and Fortenza will not affect scarring but will maintain better control of larvae.

For rice that is going to flood past the 28-35 day window with CruiserMaxx Rice or NipsIt, a foliar application of a pyrethroid like Mustang Max, Lambda-Cy, or Declare might be called for.  However, Dermacor and Fortenza will NOT need a foliar application.

Timing is critical on foliar applications for rice water weevil.  Applications must be made within 5-7 days of permanent flood establishment, as long as adults are present.  If it is later than that, our studies indicate you may as well keep the insecticide in the jug.  Your only option then is to drain the field until the soil cracks to prevent weevil damage.  Most growers aren’t crazy about doing that as it is costly and may impact weed control and fertility.  Remember, late rice will have high populations of RWW and staying vigilant with scouting and timely applications will be critical.

Rice water weevil adult feeding on rice.

Leaf scarring from rice water weevil adult feeding.

Preflood Nitrogen Management Under Suboptimal Conditions

Jarrod Hardke

Tips on managing preflood nitrogen (N) under various soil conditions:

Dry soil:  Use urea treated with a recommended NBPT product to minimize volatilization losses which occur when urea is left on the soil surface unincorporated by flood or adequate rainfall.  Potential N shortfalls can be caught and corrected with no yield penalty postflood.

Muddy soil:  Wait until around the final recommended time to apply N (based on a up-to-date DD50 report) before making risky decisions.  Once you’re around that date, use urea treated with a recommended NBPT product and apply to field.  Attempt to let the soil dry beneath the urea if possible, but if rain or conditions do not allow, then flood the field once you’re moving on past the final N date.  If muddy conditions are present and unlikely to dry before next rains, increase preflood rate by 10-20 lb N/acre and begin flooding.  Under very poor conditions, consider a 20-30 lb N/acre rate increase.

Flooded field:  If conditions create standing water through the final N date, set spills and begin applying N in a “spoon-feed” manner – 100 lb urea/acre once a week for 3-4 weeks.  For hybrids, a minimum of 3 and possibly 4 applications of 100 lb urea/acre are needed to maximize yield.  For varieties, a minimum of 4 and possibly 5 applications of 100 lb urea/acre are needed to maximize yield.

See the podcast section below for a link to a discussion of this topic.

Nitrogen Rate Recommendations

Jarrod Hardke and Trent Roberts

The Nitrogen Rate Calculator is available to help get immediate N rate recommendations for most available cultivars.  The calculator is built to account for N rate adjustments based on cultivar, soil texture (soil type), and previous crop.  These are base recommendations and actual N rate used should be adjusted based on experience and additional tools such as N-STaR sampling and GreenSeeker readings.

2021 Recommended Nitrogen Rates & Distribution for Rice Cultivars in Arkansas*.

* Base recommendations for rice following soybean on a silt loam soil.

† SPF = single preflood; PF = preflood; MS = midseason.

See 2021 Rice Management Guide for more details.

Rice Market Update

Scott Stiles

For rice it has been a shortened week of narrow trading ranges and declining volume.  Open interest was leaking steadily this week out of the old crop July contract and building gradually over in the new crop September.  Trading ranges were narrow without much news and the September contract continued to find resistance near $13.60 this week.  Planting is done.  Weather conditions and the June 30 Acreage will help drive the new crop contracts.  With no new crop sales reported as of yet, export data has not been exciting.

CBOT September 2021 Rough Rice Futures, Daily Chart.

With the calendar turning to June, traders will start to position themselves for the monthly WASDE report that will be released on the 10th.  We will also start to see more private estimates and positioning for the June 30^th Acreage report.  That is a key piece of information for the rice market going forward.  As mentioned here in previous weeks, traders are expecting to see some reduction in 2021 rice acres given the historically high prices in corn and soybeans this year.

New Crop Rice Bids / Basis:

New crop basis at eastern Arkansas driers / local elevators remained firm this week at 16 to 23 cents per bushel under September futures.  Fall delivery bids were in the $5.88 to $5.94 per bushel range as of Friday’s open.  Basis at mills was 9 cents under September futures with bids at $6.01 per bushel.

U.S. Crop Conditions:

In this week’s Crop Progress the U.S. rice crop condition improved 3 points from the previous week to 74% good-to-excellent (G/E).  Arkansas’ and Texas’ ratings slipped 1 point each to 77% and 52% G/E respectively.  California, Louisiana, Mississippi, and Missouri all saw better ratings.

As a reminder there is a weak correlation between crop ratings and production.  In other words, it is nearly impossible to forecast a yield based on crop ratings alone.  What a crop condition rating can show is how much stress the crop has been subjected to.  These numbers provided by NASS are updated weekly and released each Monday afternoon throughout the growing season.

Rice Export Sales:

For the week ending May 27^th, long-grain rough rice sales totaled 6,680 MT, a 24% decrease from the previous week and a 6-week low.  Mexico and El Salvador were the only two buyers.  Long-grain milled sales were 3,267 MT.  Mexico, Canada and Saudi Arabia made up almost all of the total milled sales.  Haiti was absent from the buyers list.  Nothing yet from Iraq.

There are nine (9) reporting weeks remaining in the 2020/21 marketing year.  Long-grain rough rice sales are running 12% ahead of last year, while milled sales are 25% behind.  Overall, long-grain sales (rough, brown, and milled combined) are 4% behind last year.  No new crop export sales had been reported by USDA thru May 27^th.  For comparison, none had been reported at this time last year.

Fertilizer Update:

Urea prices at the US Gulf increased again this week, reaching multi-year highs.  The trade indicates a strong demand for immediate delivery that has resulted in a supply squeeze.  First half of June barges traded up to $430/ton this week.  Historically high corn prices have added more acres this spring and the international urea market has been firm as well.  Chinese urea producers are showing little interest in exporting.  Their domestic prices remain firm and urea inventories are tight.  India is expected to make additional urea purchases in the upcoming weeks.

The graph below is updated thru May 28^th.  From the week ending May 7^th, Gulf urea prices increased $32/ton to an average $392.  As mentioned, prices have continued higher for a fourth straight week moving above $400 per ton.

Upcoming USDA Reports:

June 7,14,21,28    Crop Progress

June 10                Crop Production  and WASDE

June 30                Acreage   

                           Rice Stocks  

                           Agricultural Prices  

Relieve Rice from Hydrogen Sulfide Toxicity or Autumn Decline

Yeshi Wamishe and Jarrod Hardke

The production of hydrogen sulfide in some soil types due to an interplay between soil chemistry and microbes under anaerobic/ flooded conditions may affect rice starting early in its development.  Does your field have a history of hydrogen sulfide toxicity?  How long has it been since you applied the pre-flood nitrogen fertilization and established a permanent flood?  It may be time for you to start scouting for root-related problems to relieve or rescue your rice before it is late. 

Start scouting 2 or 3 weeks after a permanent flood is established.  As shown in Fig. 1, color differences in rice roots from a bar ditch or bay (left) with roots from a levee (right), respectively, are indicators of the disorder.  Make sure the roots are well rinsed before you compare them.

The Cause?  The disorder is the result of high levels of sulfur and iron in soil and irrigation water which leads to a reaction in the root zone.  This reaction occurs in anaerobic (no oxygen) conditions and results in the formation of iron sulfide that coats and blackens roots. Hydrogen sulfide formed due to anaerobic condition is often toxic to roots to extent of killing them.  The iron sulfide coating on roots can limits oxygen exchange worsening the problem. Although complex, at this level the problem is named hydrogen sulfide toxicity. The rice plants may appear stunt and lower leaves may start to turn yellowish. Symptoms are usually severe around groundwater inlets.

What happens next?  Weak pathogenic (opportunistic) fungi invade the damaged roots and make root crowns their home. As the fungi grow and multiply, the passage for minerals and water from roots to the above-ground parts of rice plants get clogged partially or fully marking the beginning of autumn decline (Fig. 2). Such a situation makes the rice plant decline or dies resulting in an estimated yield loss of up to 40 %.

Solution?  Re-introducing oxygen to the root zone (draining) reverses the reaction.  If this correction is made early enough, complete or near-complete recovery is possible and the approach is called protective strategy. However, opportunistic fungi once entered the crowns of the root system, their growth clogs the crown – once this happens complete recovery is very unlikely.

How early is early to drain?  Although you start scouting a few weeks after a permanent flood is established, give it time for the rice to use the pre-flood nitrogen. The earliest you may drain the field is at the straight head drainage timing based on DD50 which would be a little before mid-season. If drained and dried for up to 4 or 5 days you start seeing new roots growing from the side of the crown.  The re-introduction of oxygen initiates new root growth. Then after it can be re-flooded.

What if the farm size is huge and draining takes days?  Oh! That is tough! This is one of the reasons that we have to keep our field sizes manageable particularly if the field has a history.  However, you need to rescue your rice. You may start draining from the top part of the field and by the time the lower part is drained, you may start re-flooding starting from the top. Here comes a judgment call. It all depends on your resources such as water resources, pump capacity, etc.

What if the problem is discovered at some point during reproductive stages?  This one is tough too! However, again something has to be done to rescue the crop. In such cases, lower the flood depth but do not completely dry the ground. The most it can go is until it is muddy. Rice plants are very sensitive to dry conditions at reproductive stages. Moreover, remember diseases such as blasts may take advantage of the drought situation. 

Remarks:

1. Not all fields for rice production in Arkansas have shown the problem of hydrogen sulfide toxicity or autumn decline.
2. We encourage every field to be scouted for root health once in a while for this or any other root disorders.
3. We understand draining and drying is not the best option for producers with limited resources and large fields. So far, we got no other way to alleviate this problem.  With the problem starting early and left unmanaged, yield would be highly affected. You've got to act!

Fig 1.  Color difference in rice roots from a bar ditch or bay (left) with roots from a levee (right) from a field with a history of hydrogen sulfide toxicity.

Fig.2.  Growth of opportunistic fungi in a root crown clogs the passage for water and nutrients from the soil to above ground parts of a rice plant.

Row Crops Radio Podcasts

Check out these podcast episodes by following the link or by listening to them on Arkansas Row Crops Radio wherever you listen to podcasts.

Rice & Advice, Ep. 03:  Managing Preflood Nitrogen with Wet & Rainy Conditions (6-3-21)

Early Season Row Crop Insect Update (6-3-21)

DD50 Rice Management Program is Live

The DD50 Rice Management Program is live and ready for fields to be enrolled for the 2021 season.  All log-in and producer information has been retained from the 2020 season, so if you used the program last year you can log in just as you did last year.  Log in and enroll fields here:  https://dd50.uada.edu.

Use the Arkansas Rice Advisor Internet App!

The Arkansas Rice Advisor site https://riceadvisor.uada.edu functions like an app on your mobile device.  There you can readily access the DD50 program, rice seeding rate calculator, drill calibration, fertilizer and N rate calculators, publications, and more.

Additional Information

Arkansas Rice Updates are published periodically to provide timely information and recommendations for rice production in Arkansas.  If you would like to be added to this email list, please send your request to rice@uada.edu.

This information will also be posted to the Arkansas Row Crops blog (http://www.arkansas-crops.com/) where additional information from Extension specialists can be found.

More information on rice production, including access to all publications and reports, can be found at http://www.uaex.uada.edu/rice.

Acknowledgements

We sincerely appreciate the support for this publication provided by the rice farmers of Arkansas and administered by the Arkansas Rice Research and Promotion Board.

The authors greatly appreciate the feedback and contributions of all growers, county agents, consultants, and rice industry stakeholders.