Volume 13, Issue 3 - May 2023

David Moseley, Parvej, Md Rasel, Deliberto, Michael, Dodla, Syam, Villegas, James M., Wang, Jim Jian, Conger, Stacia

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Details of the Rice Production Program (RPP)

Michael Deliberto, LSU AgCenter Economist

The USDA Farm Service Agency (FSA) will provide assistance to rice growers who experienced stagnant rice prices and record-high input costs during the 2022 crop year. This one-time payment will be made under the Rice Production Program (RPP).

The RPP payment is equal to the payment rate of $0.01 per pound multiplied by the individual average APH multiplied by the amount of certified rice acres in 2022.

The initial RPP program rate will be at a reduced rate of $0.01 per pound. If funds remain at the end of the application period, a second payment, not to exceed $0.01 per pound may be issued.

To be eligible for RPP payment, a grower must have reported a share interest in rice planted or prevented from planting for the 2022 crop year. If applicable, a prevented planted factor of 60% will be applied to prevent plant acres.

The payment limit for the RPP is set by statute and is higher if the grower’s average adjusted gross farm income is more than 75% of their average adjusted gross income. A person or legal entity with an adjusted gross farm income of less than 75% of their overall AGI cannot receive more than $125,000 in RPP payments. Growers who derive more than 75% qualify for a $250,000 payment limit.

Rice growers will be mailed pre-filled applications using information on file with USDA RMA or FSA. To apply, growers must return the completed FSA-174, Rice Production Program Application, to their reporting FSDA office by the close of business on July 10th via in-person drop off, email, or facsimile.

In addition to the pre-filled applications, growers must also submit: Form AD-2047 Customer Data Worksheet, CCC-901 Member Information for Legal Entities (if applicable), CCC-902 Farm Operating Plan, Form FSA-510 Request for an Exception to the $125,000 Payment Limitation, and AD-1026 Highly Erodible Land Conservation and Wetland Conservation Certification.

Additional information can be found at: https://www.fsa.usda.gov/programs-and-services/rice-production-program/index

Iron Deficiency Chlorosis (IDC)

David Moseley, Rasel Parvej, Syam Dodla, Jim Wang, LSU AgCenter Scientist

Article Highlights:

  • If plants are deficient in iron, the symptoms begin as interveinal chlorosis in the younger leaves.
  • The conditions that promote iron deficiency chlorosis include high pH soils (>7.0) with high carbonates and soluble salt content. Cool and saturated soil conditions and high amounts of available nitrates can increase the probability of iron deficiency chlorosis.
  • Soybean plants can be sensitive to iron deficiency. However, there are varieties that are tolerant.
  • Other corrective measures include soil application of iron chelate products and foliar applications.
  • These applications may not be necessary in Louisiana since most varieties tested at the Dean Lee Research Station (location where soybean plants historically have shown symptoms of iron deficiency chlorosis) do not show severe iron deficiency chlorosis symptoms and have good yield potential.

Iron is an important element for several plant functions such as chlorophyll synthesis, photosynthesis, and respiration. If plants are deficient in iron, the symptoms begin as interveinal chlorosis in the younger leaves (Figure 1). If the deficiency is severe, the symptoms can be white or necrotic leaves (figure 2).

Soybean leaves with interveinal chlorosis.

Figure 1. Soybean leaves showing iron deficiency chlorosis symptoms

Soybean leaves with severe iron deficiency chlorosis.

Figure 2. Soybean leaves showing severe iron deficiency chlorosis symptoms.

The conditions that promote iron deficiency chlorosis include high pH soils (>7.0) with high carbonates and soluble salt content. Other conditions that increase the probability of iron deficiency chlorosis include cooler temperatures, saturated soil, high amounts of available nitrates, and compacted soil conditions. In addition, excess soil content of other nutrients including copper, manganese, zinc, and molybdenum can limit iron uptake. The iron deficiency chlorosis symptoms will often be randomly scattered based on differences in soil conditions throughout the field (Figures 3 and 4).

A soybean field with iron deficiency chlorosis.

Figure 3. Soybean plants at the V3-V4 growth stage are showing symptoms of iron deficiency chlorosis in random spots throughout a field. This picture was taken on May 5, 2022.

Soybean plants with various severity of iron deficiency chlorosis.

Figure 4. Soybean plants at the V3-V4 growth stage that are showing various degrees of iron deficiency chlorosis within the same row.

The iron deficiency chlorosis symptoms can alleviate if the soil conditions improve and/or if the roots reach a more favorable environment (warmer; less saturation or available nitrates). As the roots grow deeper, the soil can be less alkaline which will allow more available iron content. Soybean plants can show symptoms of iron deficiency chlorosis during early growth stages and become symptom free as the conditions improve (Figures 5 and 6).

A soybean field with iron deficiency chlorosis.

Figure 5. Soybean plants at the R3 growth stage. The symptoms of iron deficiency chlorosis shown in Figure 3 have decreased. This picture was taken on May 17, 2022.

A soybean field with no visible signs of iron deficiency chlorosis.

Figure 6. Soybean plants at the R4 growth stage. The symptoms of iron deficiency chlorosis shown in Figure 3 and 5 have completely waned with no noticeable differences throughout the field. This picture was taken on June 3, 2022.

If iron deficiency chlorosis is suspected, tissue and soil test should be taken. Tissue and soil samples should be taken from areas that have symptomatic plants and plants showing no symptoms. This comparison can help determine what the deficiency may be. If any soil residue on the leaf surface contaminates the tissue sample, the collected tissue samples should be rinsed off with deionized water and the excess water should be dried before sending the sample to the lab.

Soybean plants can be sensitive to iron deficiency. However, there are varieties that are tolerant (Figure 6). Tolerance is based on a genetic variation that allows the plant to change the environment around the root by excreting H+ or organic acids and chelating compounds. These excretions from the roots increase the availability and uptake of iron by the plant.

Soybean plants with various degrees of iron deficiency chlorosis.

Figure 7. Iron deficiency chlorosis in soybean on high pH soils (~8.0) at the Dean Lee Research Station, Alexandria, LA. There is a noticeable difference in iron deficiency chlorosis symptoms between two varieties. The variety on the left shows more tolerance than the variety on the right. The picture was taken by Dr. Rasel Parvej, State Soil Fertility Specialist, LSU AgCenter.

Other corrective measures include soil application of iron chelate products and foliar applications. These applications may not be necessary in Louisiana since most varieties tested at the Dean Lee Research Station (location where soybean plants historically have shown symptoms of iron deficiency chlorosis) do not show severe iron deficiency chlorosis symptoms and have good yield potential. Therefore, when selecting a soybean variety, look at the yield from the Dean Lee Research Station to see if the variety was competitive. The seed companies may also have an iron deficiency chlorosis tolerance rating.

Experiments conducted by LSU AgCenter scientists at the Red River and Dean Lee Research Stations have shown up to 7% or 4 bu/ac improvement in grain yield with the soil application of iron chelates (Figure 7). In furrow application of iron chelates at 0.25 lb Fe/ ac could be beneficial for the soils with potential iron deficiency chlorosis.

A graph showing some increase in yield after applying iron to soybean that have iron deficiency chlorosis.

Figure 8: Effect of Iron application (as Fe-EDDHA with 6% Fe) on soybean grain yield at Dean Lee Research Station

Importance Of Tissue Nitrogen Testing For Determining Pre-tassel Nitrogen Need In Corn

Rasel Parveja, Jamil Uddinb, and Syam Dodlac

a LSU AgCenter State Soil Fertility Specialist, b LSU AgCenter Postdoctoral Researcher, and c LSU AgCenter Soil Scientist

Article Highlights:

  • Leaf tissue sampling is one of the best indicators of determining N losses after sidedress and pre-tassel N need for maximizing corn yield.
  • Leaf tissue sampling should be done from V10 (10 collar leaf stage) to pre-tassel stage.
  • The sufficient leaf-N concentration from V10 to R1 (silking) stage should be over 3.1%.

Corn tissue testing is one of the important tools that guides whether pre-tassel nitrogen (N) is required. To evaluate N losses due to excessive rainfall after sidedress, producers need to wait until V10 stage (10 collar leaf stage) and take tissue samples at or after V10 stage. Tissue sampling can be done anywhere from V10 to R1 (silking stage) stages but earlier (V10) is better if the fields are experienced water-logged conditions for several days. For tissue testing, the uppermost fully developed leaf with visible collar below the whorl (Figure 1) from 10-15 plants should be collected and sent immediately to the lab for total N concentration. For a large field, several composite tissue samples from different parts of the field should be collected to better understand corn N status and follow up management. The critical corn leaf N concentration from V10 to R1 stage ranges from 2.9 to 3.1% (Figure 2). Leaf N concentration below 2.9% would be considered deficient (additional N is needed for maximizing yield) and above 3.1% would be sufficient (no additional N is needed). Care should be taken in collecting leaf tissue sample and interpreting N concentration because leaf N concentration can be high due to insufficient plant growth (low dilution) associated with drought, diseases, and pest infestation.

Once the producers decide to apply pre-tassel N based on tissue N concentration, the rate should be 15 to 25% of the total N applied i.e., roughly 40 to 60 lb N/acre. Producers can choose either dry (Urea, 46-0-0) or liquid (UAN, 32-0-0, 30-0-0-2S, or 28-0-0-5S) N source. Urea can easily be flown by airplane. UAN should be applied as surface application because high rates of UAN (without water dilution) as foliar application will result severe foliage burn. However, producers can apply UAN through their pivot irrigation system, if available, as fertigation. Regardless of N sources, it would be better to place N fertilizer close to plant base, if possible, with high clearance applicator using “Y-drop” to facilitate rapid uptake, minimize N losses, and avoid foliage damage. Application before a “known rain” (0.25-0.5 inch) or pivot irrigation is recommended to incorporate applied N that will minimize volatilization loss. Further, use N-stabilizers (urease inhibitor) to reduce volatilization loss. Experiments conducted at LSU AgCenter showed that when urea was surface applied at late growth stages, use of N-stabilizer decreased ammonia volatilization losses by 74% and increased corn grain yield by 12 to 25% compared to uncoated urea. Overall, a producer should consider rainfall amount following sidedress N application, field conditions, crop growth, yield potential, and tissue-testing to evaluate N losses and pre-tassel N application.

Corn plants in a field.

Figure 1. Corn leaf collar. Photos were taken from (A: sites.udel.edu/agronomy; B: webapp.agron.ksu.edu and C: edis.ifas.ufl.edu

A graph showing various amounts of leaf nitrogen concentration and relative grain yield.

Figure 2. Critical leaf nitrogen concentration from V10 to R1 stages of corn. (Source: Dr. Trent Roberts, University of Arkansas)

Irrigation Scheduling Tool Delayed Through Memorial Day Weekend

Stacia L. Davis Conger, Ph.D., State Irrigation Specialist, LSU AgCenter

The previously advertised Drought Irrigation Response Tool (DIRT) is still in development by LSU AgCenter IT currently. Progress was going well as we approached the planned release date at the end of March, but a systemwide compromise was detected within our IT’s infrastructure that diverted all our development resources. Our team was reprioritized toward securing the current network, increasing security features to prevent future compromises, and repairing the many existing webtools featured on the AgCenter’s website. The month of April was filled with uncertainty, but the development team is back in place and moving forward with an expected release by the end of May. In the end, I hope the tool’s usefulness during drought will be worth the wait.

If you would like to be notified when the tool becomes available, please sign up here: https://forms.office.com/r/A4KL9Xapf9Those that signed up previously and preferred email communication but was not able to enter an email address should sign up again. We appreciate your continued support as we work to bring scientifically-backed resources to scheduling furrow irrigation.

Strategies for Managing Thrips in Louisiana Cotton

James Villegas, LSU AgCenter Entomologist

Thrips management is a crucial aspect of successful cotton production and requires proactive measures from the outset. Thrips possess a unique biology that makes precise timing of insecticide applications difficult without seed treatments. Their eggs are typically deposited in the cotyledons, and as the first true leaf emerges, immature thrips hatch and prefer to feed within the furl stage. Unfortunately, they are well-protected within the furl, making it extremely challenging to reach them with insecticides. Consequently, the first true leaf often sustains damage before it fully expands. Effective thrips management requires realistic expectations for sprays and consideration of the thrips' life cycle.

  • Insecticide Seed Treatments (ISTs): ISTs are the primary strategy for controlling thrips. Their effectiveness varies based on the prevailing weather conditions and the level of thrips infestations. In low to moderate-pressure situations, ISTs can effectively control thrips. However, under high pressure or unfavorable growing conditions, supplementary foliar treatments may be necessary.
  • In-Furrow (IF) Applications: In-furrow treatments provide another effective method for thrips management. Several options include acephate (note that pockets of acephate-resistant thrips have been detected in portions of the state), imidacloprid, and aldicarb (AgLogic). Additional foliar applications for thrips control are typically unnecessary when cotton is treated with aldicarb.
  • ThryvOn: ThryvOn, a new Bt trait, offers an exciting at-plant option for thrips management. ThryvOn demonstrates high efficacy against thrips and may eliminate the need for supplementary foliar treatments. Furthermore, ThryvOn exhibits efficacy against tarnished plant bugs, albeit to a lesser extent than thrips.

Supplemental foliar insecticides for thrips management - if additional foliar insecticides are required to manage thrips, several options can be considered:

Foliar Insecticide/Active Ingredient)

Rate (fl oz/acre

Comments

Orthene (acephate)

3.0

-effective and cost-efficient choice, but it may result in secondary pest outbreaks like spider mites and aphids

Bidrin (dicrotophos)

3.2

- effective alternative and less likely to flare spider mites and aphids

Dimethoate (dimethoate)

6.4

-cost-effective, good efficacy at high rates, minimizes the risk of spider mite issues compared to acephate

Radiant (spinetoram)

1.5 – 3.0

-effective, requires adjuvant, least likely to flare spider mites or aphids

Intrepid Edge (spinetoram + methoxyfenozide)

3.0

effective, similar activity to Radiant, an adjuvant may be necessary to enhance the efficacy

To ensure a fast and vigorous start for cotton, effective thrips management is crucial. The recommended approach involves utilizing suitable at-plant insecticides, such as ISTs or in-furrow treatments, or considering the adoption of ThryvOn cotton. It is important to note that foliar insecticides should be used as supplementary measures to at-plant treatments, rather than replace them. For more information on thrips management, please check out the LSU AgCenter Insect Pest Management Guide (https://www.lsuagcenter.com/portals/communications/publications/management_guides/insect_guide).

LSU AgCenter Specialists

Specialty Crop Responsibilities Name Phone
Corn, cotton, grain sorghum Agronomic Matt Foster 601-334-0354
Soybeans Agronomic David Moseley 318-473-6520
Wheat Agronomic Boyd Padgett 318-614-4354
Pathology Cotton, grain sorghum, soybeans Boyd Padgett 318-614-4354
Pathology Corn, cotton, grain sorghum, soybeans, wheat Trey Price 318-235-9805
Entomology Corn, cotton, grain sorghum, soybeans, wheat James Villegas
225-266-3805
Weed science Corn, cotton, grain sorghum, soybeans Daniel Stephenson 318-308-7225
Nematodes Agronomic Tristan Watson 225-578-1464
Irrigation Corn, cotton, grain sorghum, soybeans Stacia Davis Conger 904-891-1103
Ag economics Cotton, feed grains, soybeans Kurt Guidry 225-578-3282
Precision ag Agronomic Luciano Shiratsuchi 225-578-2110
Soil fertility
Corn, cotton, grain sorghum, soybeans Rasel Parvej

5/23/2023 2:46:02 AM
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