July 31, 2015 No. 2015-23
Dr. Jarrod Hardke, Scott Stiles, & Dr. Yeshi Wamishe
It’s a good indication of the recent high temperatures when 91 degrees feels like a cold snap. The greatest thing about our current weather change isn’t just the reduced daytime temps making it easier on us, but the reduced nighttime temps making it easier on the rice plants. A weed in the upper 60s and low 70s is just what we needed. Temperatures next week are supposed to increase again, but not back to where they were.
There’s a notable lack of rainfall in the forecast except for a few chances mid-week for the northern part of the state. At this stage a lack of rainfall is a blessing and a curse. No rain means more irrigation, but no rain and warm temperatures mean fewer disease problems.
According to DD50 enrollment, the first fields will be reaching harvest moisture (20%) this coming week (Table 1). It’s very likely that a few fields will be harvested by next weekend. So for some the beginning of the end is in sight.
Friday, Aug. 7th Grand Prairie Center, Stuttgart, AR.
Field tours leaving the Grand Prairie Center at 8:15, 8:45, and 9:15 a.m. Program:
- Karen Moldenhauer & Steve Linscombe, Arkansas & Louisiana Breeding Updates
- Pengyin Chen & Jeremy Ross, Flood Tolerant Soybeans & AR Soybean Update
- Jason Norsworthy & Jarrod Hardke, New Weed Control Technologies & AR Rice Update
The very first fields in the state are being drained this week. Drain timing is and always will be a subject that involves as much art as it does science. Fig. 1 shows (if you look closely) a range of panicle maturity in the same field.
Fig. 1. Range of panicle maturity in the same field, making draining decisions difficult.
The general rule is that you should wait to drain until 25 days after 50% heading for long-grain cultivars and 30 days after 50% heading for medium-grain cultivars. There’s a reason that it’s a general rule – temperature, rainfall, humidity, etc. play major roles in the relative drying time of grain in the field. These factors cannot be predicted for every field and cultivar.
To improve on the decision-making process, you should combine the general rules of days past 50% heading with a field-based observation of the relative maturity of grain in your field. Fig. 2 provides a guide for determining relative grain maturity. At left – nearly all kernels are straw-colored and the field is well past the point that it is safe to drain regardless of soil type. At center – nearly 2/3 of kernels are straw colored and it is safe to drain on a silt loam soil. At right – 1/3 of kernels are straw-colored and would be close to the point where it is safe to drain on a clay soil. Always use caution when deciding to drain – pulling the water too early can sacrifice grain fill of the lower kernels and impact yield.
Fig. 2. Rice panicles at different maturity levels described by percent straw color:
(L) 100%, (C) 67%, and (R) 33%.
Determining 50% Heading
Based on questions received, there needs to be some better explanation of the “50% heading” timing referred to so often in our recommendations and the DD50 program. Agronomically, “heading date” or “50% heading” is defined as the time when 50 percent of the panicles have at least partially emerged from the boot. This is in contrast to “headed” which refers to the time when 100 percent of the panicles have completely emerged from the boot (some panicles may never completely emerge from the boot).
In Fig. 3 are three plants at different stages of panicle emergence. At left, the plant is at boot-split; at center, the plant is at what is commonly referred to as “cracking the boot”; and at right, the plant is heading. Note that the center plant at cracking is not at heading yet – the panicle has not yet begun to extend above the flag leaf collar. So, 50% of your plants should look like the plant at right to say that your field has reached 50% heading.
Fig. 3. Panicles at varying stages of panicle emergence:
(L) boot split, (C) cracking the boot, and (R) heading.
Sheath Blight: The heat in the past few weeks has not been favorable for sheath blight. However, in fields where N is excessive and the canopy is dense to retain nighttime dew, the disease can slowly progress. We have seen this in our test plots. Continue scouting and make sure the upper three leaves including the flag leaf are clean from the disease at heading. One time application at early to mid boot is recommended as the best timing and economical to suppress sheath blight progress for Arkansas. However, one-time application may not be viable in poorly managed fields where the disease started early in short, susceptible cultivars under favorable weather conditions. More on sheath blight: http://www.arkansas-crops.com/2015/07/15/rice-sheath-blight/.
Blast: We have received a few reports of blast in the past week. The scattered rain showers have been a concern in a few counties in northern Arkansas for blast progress. However, the disease has not progressed much due to the heat. Fields that have difficulty maintaining flood depths had more blast spread across the field. There have been repeated questions on making only one application for blast instead of the recommended two-application approach. One application is not recommended, particularly in late planted blast-prone fields with susceptible cultivars. If you decide to make only one application, use a higher fungicide rate at 30-50% head emergence. The recommended two-application approach is for the first application at boot to 10% head emergence and the second application at 50-75% head emergence. If the necks are emerged from the boot you are too late and there will be no benefit from a fungicide application. Read more on blast: http://agfax.com/2015/06/05/arkansas-rice-12-conditions-that-favor-blast/ and fungicide timing: http://www.arkansas‑crops.com/2015/07/17/arkansas-rice-update-17-15/.
Bacterial Panicle Blight: The scorching heat in the past three weeks has been a concern for BPB occurrence. None of the suspicious samples received from commercial fields this year have tested positive. Research has shown that the incidence and severity of the disease increases in late planted (late May) than early planted (March and April). Dew has also shown to play a great role in BPB disease development. Continue scouting in late planted fields. Keep us informed if you see any. To read more on BPB and the symptoms: http://www.uaex.edu/publications/pdf/FSA-7580.pdf.
Kernel Smut and False Smut: We received repeated questions on timing and rate of fungicide application to suppress these two diseases. Early to mid boot applications have been recommended with a minimum of 6 oz/A Tilt (propiconazole) or equivalent. High rates are recommended such as 19 fl oz Stratego, 21 fl oz Quilt Xcel, or 21 oz Quilt. These diseases are severe in fields with a history planted to susceptible cultivars. Excessive N fertilization and high seeding rates increase the disease situation. False smut is less sensitive to fungicides and is more prevalent in late-planted fields. Applying fungicides earlier than early boot may not last long enough to offer the desired suppression. Applying after boot split is too late and there will be not benefit for smut management.
Fig. 4. Boot split to any percentage head out is too late for a fungicide application for kernel smut and false smut suppression.
To read more on fungicide rates and contents of fungicides go to: http://www.arkansas-crops.com/2015/06/18/contents-fungicides-diseases/.
Weekly Market Summary
September 2015 rice futures finished 8 cents higher Friday at $11.515 and 47 cents higher on the week. Rice was in a league of its own as corn, wheat, soybeans and cotton all lost ground this week. News behind this week’s sharp gains in rice is hard to find. Some have pointed to the continued concerns about drought in Southeast Asia. But, that is a known fundamental and has been for some time now. The sharp gains this week would seem to indicate another large sale of rice will soon be announced. Thursday’s Export Sales report did provide a boost to the market with the inclusion of a 30,000 metric ton new crop sale to Venezuela.
CBOT Rough Rice futures settlements ($/cwt)
The September 2015 weekly futures chart (shown below) has a couple of interesting things to watch. Firstly, as prices have turned higher since mid-May, the contract has also moved out of its’ down-trending channel that extends back to last summer. At present, technicians would be quick to point out that the contract may be making a “double top” formation at the March 30 high of $11.51. If the contract can settle (close) above this price level, the next objective higher would be the weekly chart price gap between $11.96 and $12.17 that was left last December.
CBOT September 2015 Rough Rice weekly futures chart.
Monday: Crop Progress
For the week ending July 26, U.S. rice condition ratings declined three percentage points to 69% good-to-excellent, compared to 72% last week and 71% last year. Crop conditions improved slightly week-to-week in Mississippi, but were significantly lower in California and Louisiana. NASS also indicated that 51% of the U.S. crop was at “heading”. This is ahead of the five-year average pace of 45% for the week.
Thursday: Export Sales
Long-grain Rough Rice:
Old crop exports were steady week-on-week at 40,558 metric tons (MT). Shipments were made to Venezuela (29,934 MT) and Mexico (10,624 MT). Net Sales of old crop rough were off sharply from the previous week, reaching a 15-week low of 1,256 MT. A large new crop sale of 30,000 MT to Venezuela was listed. Other new crop sales were made to El Salvador, Honduras and an “unknown” origin. Total Commitment for new crop now stands at 72,245 MT.
Long-grain Milled Rice:
Old crop exports and sales were down from the previous week. Milled rice was shipped to 15 destinations, the majority going to Haiti (10,001 MT). Sales were made to 13 countries last week, with the largest buyers being Mexico, Canada and the U.K. Total net sales were 2,726 MT, down from 16,103 MT the week prior. New crop milled sales were very lite at 326 MT. Total Commitment for the 2015 marketing year is now 122,665 MT, most of which accumulated last week with sales of 120,000 MT to Iraq and Iran.
As a reminder, crude oil has been trading below $47 per barrel today and NYMEX diesel futures are still trading near the January 2015 lows at $1.58. This should be closely watched. A year ago, diesel futures were trading at $2.87. Today, prices are 44% below that level. It’s a good opportunity to get fuel in storage for harvest. It’s also a good time to think about projects that consume a lot of fuel like land-leveling and sub-soiling. If your fuel storage is maxed-out, visit with a commodities broker about hedging future fuel needs at these low price levels.
NYMEX Diesel, daily nearby futures.
Upcoming USDA reports:
August 12 (11:00 a.m. central):
- Crop Production
- Supply/Demand (WASDE)
NASS Crop Progress is released each Monday afternoon at 3:00 p.m. central.
FAS Export Sales are released each Thursday morning at 7:30 a.m. central.
USDA-FSA information on projected 2014 PLC payment rates is available at this link:
The DD50 program can be accessed at http://DD50.uaex.edu. It has now been improved for use on both your computer and your mobile devices.
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 firstname.lastname@example.org.
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.edu/rice.
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.