Agfax Buzz:
    July 3, 2014
    Rice fields underwater due to excessive rainfall in Hunter, AR.

    Arkansas Rice: “Underwater” Diseases

    AgFax.Com - Your Online Ag News Source

    By Yeshi Wamishe, University of Arkansas Extension Rice Plant Pathologist

    Rice fields in some counties are “underwater “due to the excessive rain in the last days of June. As I drove (07/02/14) in Monroe, Woodruff, and St. Francis Counties, I saw fields of soybean and rice covered with water. Information on soybean conditions has been given here. Though not as fast as soybeans, rice in an “underwater “situation could also die unless it possesses specialized genes that enable it to breathe.

    The rice cultivars we grow here currently do not have those genes to my knowledge. However, as rice is more resilient under excessive water, I would like to speculate the possible disease related problems that may be associated.




    Although rice leaf blast has been on the go in the last two weeks, the fungus that causes rice blast does not like anaerobic conditions. Therefore, the disease would be suppressed and momentarily, it will not be a problem in these fields.

    Autumn decline that makes roots black and causes root rotting is a phenomenon that worsens in anaerobic conditions. Therefore, the excessive water could aggravate the problem more in fields with history.

    Rice fields underwater due to excessive rainfall in Hunter, AR.

    Image from University of Arkansas Rice fields underwater due to excessive rainfall in Hunter, AR.

    The fungus that cause sheath blight in rice is ubiquitous and may take chance to reach to the upper canopy faster than normal since the fungus structures that start infection normally float on flood water. Infection could start at any water level in the height of the crop. Therefore, it is likely to detect sheath blight lesions at the upper leaves and sheath after the flood subsides. Note that the upper three leaves including the flag leaf are very important for yield and quality of rice grain and they should be protected.

    Other than these, stress symptoms and minor root, sheath and leaf diseases may also be associated in incidental underwater situations. Too much of a good thing may not be necessarily good.

    What we need to do:

    If possible, lower the water level to salvage the crop as soon as possible.

    Scout for autumn decline (black root rot). Rice roots from the deep water part of the field (which is anaerobic) need to be compared with rice roots from the levee. In the presence of autumn decline, the field needs to be “drained and dried” to allow oxygen in to soil. To read more on scouting and management of autumn decline, go here.

    Scout for sheath blight–taking the level of excessive water into consideration, scout both lower and upper rice crop canopy for possible sheath blight lesions. To read more on scouting and management of sheath blight go here.


    Tags: , , , , , , ,

    Leave a Reply

    Name and Email Address are required fields. Your email will not be published or shared with third parties.

    Agfax Rice News

    AFB Rice Close: Futures Fractionally Mixed9-30

    Texas Crop Weather: Hay Supplies Range from Surplus to Practically Non-Existent9-30

    Keith Good: ‘Misinformation’ Muddles Clean Water Act, EPA Chief Says9-30

    California: Rice Harvest Progress as Rains Move Through Northern Areas – USDA9-29

    AFB Rice Close: Futures Lower on Inside Day9-29

    Mississippi: Dry Weather Prevails, Good for Field Work — USDA9-29

    Arkansas: Corn, Rice Harvest Start to Wind Down – USDA9-29

    Texas: Harvest, Wheat Planting Continue Among Widespread Rains – USDA9-29

    Arkansas: Rice Verification Program Weekly Update9-29

    Soybean Harvest Rises by 7 Points, Corn 5 — DTN9-29

    Missouri: Corn, Rice Harvest Make Good Progress, Soybean Harvest Begins – USDA9-29

    Louisiana: Harvest Speeds Along with Drier Weather – USDA9-29

    Horizon Ag Rice Harvest Report: Rough Start, Good Yields9-29

    Keith Good: Plunging Corn, Soybean Prices May Strain Farm Budgets9-29

    Rice: Mexico To Restore Import Tariffs on Asian Rice9-26

    Rice Crop: Delta Area Harvests Picking Up Steam9-26

    Rice Market: Strong Friday Push Makes for a Positive Week9-26

    AFB Rice Close: Futures Post Strong Gains9-26

    Louisiana: Ag Officials Ask for New Rules for Drones9-26

    Crop Insurance Details Clearing Up — DTN9-26

    Keith Good: River Transportation System ‘Overstrained,’ Report Says9-26

    Crop Insurance: ARC-PLC Regulation and Decision Tools9-25

    AFB Rice Close: Slightly Lower in Narrow Range9-25

    Taxes: Definition of Insanity, Cheat the IRS on Land Sales – DTN9-25

    U.S. Energy: Weak Demand, Plentiful Supply Drive Drop in Oil Prices9-25

    Gasoline Prices: Average Down 6 Cents9-25

    Propane Stocks: Rise by 1.7M Barrels9-25

    Diesel Prices: Lowest in Over 2 Years9-25

    Big Data Drives Smarter Decisions on Farm — DTN9-25

    Keith Good: Potential for Global Glut of Cotton Keeps Prices Falling9-25

    AFB Rice Close: Futures Continue Recovery in Narrow Range9-24

    Keith Good: Rebound in Global Grain Supplies to Have ‘Broad Effects’9-24

    Keith Good: Growers Encouraged to Wait in Choosing Farm Bill Program9-23

    Crop Progress: Corn Harvest at 7%, Soybeans 3%, Cotton 8% — DTN9-22