The Rice Update is a weekly summary of what’s happening and what to look for in rice production, based on interviews and submissions of rice experts in Arkansas and the Mid-South.
Weather: To heck with the forecast, we need a rain!
Dr. Chuck Wilson, Director of the Rice Research and Extension Center and Rice Agronomist, University of Arkansas Division of Agriculture:
We estimate the crop to be about 12% headed by the end of this week, which is 2-3 weeks ahead of normal for us. Day temperatures are getting hot, but as long as night temperatures stay 74 or lower we should be OK. Unfortunately, some forecasts are for hotter night temps in the near future; we hope this does not happen. We are in bad need of a rain.
Dr. Gus Lorenz, Professor and UA Division of Agriculture Extension Entomologist:
Rice stink bugs are moving in to the early heading rice fields, as we would expect. These first fields should be closely monitored the next few weeks as they will attract the available population until enough rice is heading and in grain filling to scatter them out. However, we believe pressure is down overall, so we hope this means that the crop will not suffer as much pressure as last year. Remember, the threshold is 5 bugs per 10 sweeps the first two weeks of heading and 10 bugs per 10 sweeps afterward, and the Karate, Mustang Max and generic pyrethroids are still fine to use in Arkansas. Always read and follow the labels.
Rice water weevils have been reported in a few fields but statewide are not that bad.
Dr. Yeshi Wamishe, Assistant Professor and UA Division of Agriculture Extension Plant Pathologist:
The actual cause for root blackening and rotting in rice is still a mystery. We still do not have strong evidence why in some soils roots turn black and rot in anaerobic (flooded) conditions (Fig. 1). However, we know that opportunistic fungi grow in the crown (Fig. 2) and the whole root system shuts off and the plants eventually die.
Below are some observations made by Drs. C. Wilson and R. Cartwright of University of Arkansas, Cooperative Extension Service in 2004.
1. The problem was noticed first and appeared worse where water entered the field (cold water paddies).
2. The crown rot symptom were found on scattered plants in cold water checks in many fields across the state; however the widespread problem affecting large areas of a field was confined to only a handful of fields in the counties mentioned at that time.
3. All affected fields had high soil pH.
4. Soil types varied from silt loam to clay loam.
5. All wells observed at the time were pumping iron-laden (orange) water.
6. All severely affected fields had water pumped on them a lot (it seemed) so they suspected the water temperature might have stayed consistently lower in these fields than others – and other well water related factors might be spreading further than normal.
7. Wells observed at the time were reported as 100-150 ft deep.
8. Cultivars affected at that time were Cocodrie, Wells and CL161, although most were probably susceptible.
9. The fields had several herbicides, and not all were the same ones. Grandstand appeared to be the only consistent one used in most of the severely affected fields, but it was not thought to be the original cause.
10. The paddy rice was affected; the levee rice was not.
11. The soil and roots smelled mucky but not like rotten eggs. Sometimes they smelled a little nasty (sewage) but not always. In fields in previous years where hydrogen sulfide toxicity was suspected, the water and roots did smell like rotten eggs.
12. They found islands of healthy rice in some affected paddies (Arkansas County) and healthier streaks and patches in other fields (Lonoke Co). These were surrounded by sick rice.
Last week, we visited a field planted in Cl 151 and CL152 in Northeast AR with similar symptoms described above. The rice was at 1 inch internode elongation. Most of the field was affected although symptoms were worse in the deeper water areas and near water inlets. Many plants had rotted or rotting roots, and the rot was spreading upward into the crowns. Once removed from the water, the blackening on the roots and lower part of the plants disappeared. Although it is likely unrelated, we noted many tiny snails hanging on the leaves in this field (Fig . 3).
In the past, diagnostic soil, water and plant samples have not indicated conclusive or consistent factors associated with the condition. Previously, Wilson and Cartwright indicated that “growers managed the problem by draining to aerate the crowns and roots and after a few days recovery with new white lateral root growth evident, re-flooded the fields and the rice made it. Afterwards, we advised these growers to simply drain and dry the soil in these fields as for straighthead (straighthead timing), and this has helped prevent the problem from re-occurring. While draining at straighthead timing does not completely cure this problem (it can reappear later in the season), it interrupts the process long enough to allow roots to grow out and sustain the plants to normal harvest date.”
Whatever the cause, growers have learned that aeration of the system is their only management option when the problem is noticed and most have figured out how to carefully drain down until they can see new white roots forming, then reflood. Growers are very careful not to let the soil get dry if the rice is midseason or later, as rice in these later stages is so sensitive to drought stress. It is a risky balancing act and they watch the field daily during the process, looking for new white roots each morning, and it shows how good our farmers are at managing this crop under difficult circumstances. Most have told us that doing nothing resulted in huge yield losses in the past as root systems completely died as did plants during the late boot to heading and grain fill stages, when water demand gets so high. Without a root system, the plants simply wilted in the flood and eventually passed on.
Stay in front of rice blast. Last month we heard that rice blast had gotten bad in Southern Louisiana and last week in Texas, both on Clearfield 261. This week we observed blast on CL 261 in east Central Arkansas. In one of the fields, the disease had already progressed towards the middle of the field and in the other field, it was starting right at the edge of the tree lines. In both fields, conditions were very favorable for this disease, that is, a very susceptible variety was planted, fields were surrounded by trees to some extent which promoted extended dew on the plants, and a deep flood was not able to be maintained consistently. The following pictures were taken June 26, 2012.
On CL261 and similar varieties, leaf blast can create “burn-down” areas and later this will contribute to the potential for neck blast across the field, of course depending on the weather. For fields with a history of severe blast, planting a resistant variety is the best option, if one is available. During the season though, if blast is found, pumping up the field and maintaining a minimum 4 inch flood consistently will greatly reduce the potential for severe disease, and fungicides will have to be considered. Timing of the fungicides is everything with blast, and spraying earlier is better than waiting too late. Once heads have emerged fully from the boot, it is too late to obtain the best control with our fungicides. If two applications are to be made, the first should be when main tillers are at boot split and the second when heads are around ¾ of the way out of the boot (but the bottom ¼ and neck are still down in the boot). If only one heading application is to be risked, then research has shown the best timing to be when the main tillers have panicles about 1/3 – ½ of the way out of the boot (but the bottom 2/3 to ½ still down in the boot). The higher labeled rates of our fungicides are most effective on this disease.
As rice enters boot to early heading this week in some fields, now is the time to look around and “stay in front of rice blast”.
Scott Stiles, Extension Instructor and Economist:
Chicago rice futures have moved higher this week with the September contract gaining about 43 cents per cwt (~19 cents per bu.) as of Tuesday morning and trading near $15.15 per cwt. This week’s rally has been supported by weather-related price strength across the grain complex. Per Monday’s NASS Crop Progress report, U.S. corn and soybean conditions declined for the third consecutive week. Adverse weather considerations are also impacting areas of China, the EU, and portions of the FSU. NASS lowered the percent of Arkansas’ rice crop rated “good/excellent” in yesterday’s report by 1 percentage point. With more triple digit temperatures in the forecast for later this week crop conditions may decline further in next Monday’s Crop Progress report.
Other Upcoming Reports:
USDA will release its Acreage report on June 29. The results will be based on grower surveys taken during the first two weeks of June. In the March USDA Prospective Plantings report, U.S. growers intended to plant 2.561 million acres of rice. Some pre-report private estimates indicate total rice acreage in the June 29 Acreage report may be less than the March intentions. A spike in urea prices as rice planting got underway and continued strength in soybean prices may contribute to lower final rice acres. However, a favorable planting window may have held intended rice acreage steady.
USDA will also release its Rice Stocks report on June 29. This provides an indication of June 1 U.S. rice inventories. It’s expected that all rice stocks will be down 17 to 18 million hundredweight from last year.
USDA’s Acreage and Rice Stocks reports could have some influence on the futures market. Given the fact that U.S. 2012/13 rice inventories are expected to tighten, any significant drop in planted acreage from the March acreage intentions could pull prices higher. The opposite is true if the favorable weather this spring encouraged growers to add acres. The futures market will try to balance any acreage adjustments with the impact that high temperatures and dry conditions will have on yields. For now, it appears that fund investment may move back into grains and rice will benefit from any continued strength in corn, soybeans and wheat. Reward rallies as weather markets correct themselves quickly. Futures markets take the stairs up and the elevator down.
Expect urea prices to firm up in the short term as the market digests weak seasonal fertilizer demand and the future implications of the ongoing rally in grain prices. Nevertheless, Gulf urea has fallen sharply over the past two months with granular prices trading around $670 to $700 per ton in early April and moving down to $400 by mid-June. Local retail prices are mostly in the mid-$600s now in eastern Arkansas following the price spike in February/March that took prices to $800 or so.
Since May, the price of crude oil has fallen from $106/barrel to $78/barrel. Heating oil futures have dropped 80 cents per gallon from the mid-March highs. The fundamentals in the oil market remain very weak. For the first time in a decade, supply is exceeding demand. This is a welcome event with irrigation in full swing.
Ron Baker, County Extension Agent, Clay County:
Rice looks pretty good, and we have a bit of XL745 starting to head, the first time for June heading that I can remember. We are not seeing much in the way of diseases or other problems. Fields tend to look better from the road, and several fields seem to be a bit short once you get out into them.
Randy Chlapecka, County Extension Agent, Jackson County:
Rice crop looks OK, but we are really trying to keep up with pumping. Not much disease has been reported, and we are noting a few late grass escapes. Rice seems a bit short and off-colored out in some fields.
Jason McGee, Rice Consultant:
Clearfield 111 is starting to head in our area, and CL 151 is in late boot. Our Francis fields are starting to head as well. We have not observed much sheath blight to date, and our smut treatments have generally been applied or are being applied on later fields this week. Some growers are shuffling water around to keep it moving and not stagnant in some fields with problems the past two years.
Rick Thompson, Rice Consultant, Poinsett County:
We are a bit worried about the forecast heat, but our rice fields are looking pretty good at present. We are holding off on extra fertilizer on CL 151 so that we don’t knock it down later, but we had other fields that needed some help as they yellowed up two weeks prior to green ring. These look OK now after early midseason applications. Smut applications have been made.
EAST CENTRAL ARKANSAS
Brent Griffin, County Extension Agent, Prairie County:
There are quite a few heads out in the early planted fields and some some stink bugs, but pressure is pretty moderate overall. Sheath blight is in CL 151 and somewhat aggressive in a few fields, but we have treated. Stratego has been widely used in some areas. One of our main concerns is water—will we have enough—especially with the crop mixture this year.
Robert Goodson, County Extension Agent, Prairie County:
A few rice fields with early heads but most are booting, and we have not noticed particular problems this past week or so, except WE NEED RAIN.
Grant Beckwith, County Extension Agent, Arkansas County:
Our area remains concerned about water as the drought continues. Rice looks OK overall, but some farms are struggling to keep up with water demands across multiple crops. There have been limited sheath blight applications, and the smut treatments have already gone out. We are worried about the night temperature forecasts but hope they will continue to stay moderate.
Wes Kirkpatrick, County Extension Agent Desha County:
Rice crop looks pretty good with a few fields starting to head. We have had a bit of sheath blight reported but not much in the way of problems at present.
Gus Wilson, County Extension Agent Chicot County
Rice fields look pretty good and pretty clean. We have a little sheath blight reported and fungicide treatments being made, but this is pretty ordinary. We haven’t received any reports of heading yet.
Please direct all questions and concerns to Dr. Rick Cartwright, who can be contacted at email@example.com .