Field Day

The Rice Research Station is the place to be June 28 for the annual Field Day.

In the above picture, LSU AgCenter county agents and Rice Research Station scientists ride by the blog field during preparations for the Field Day.

The day starts at 7:30 a.m. with field tours continuing until 9:30 a.m.

A poster session highlighting research and agricultural products will be held from 7:30 a.m. until 10:30 a.m. Dr. Johnny Saichuk, LSU AgCenter rice specialist, will be available to provide answers to questions about their crop. Farmers who have questions related to diseases, insects or weeds should bring samples.
The program starts at 10:45 a.m. with a review of Louisiana Rice Research Board activities by LRRB vice chairman Jackie Loewer. He will be followed by Johnny Broussard, USA Rice Federation legislative affairs director, who will give an update on the latest developments in congress related to the farm bill and how it could affect rice farmers.
Dr. Mike Salassi, LSU AgCenter economist, will discuss rice economics, and the program will end with remarks from Dr. Bill Richardson, LSU AgCenter chancellor.

Panicles are emerging

As you can see from the above photo, the blog field shows a wide variety of maturity. Some plants are fully headed, while the panicles on other plants are just starting to emerge from the boot, the sheath of the flag leaf, the tallest and last leaf to form on a plant. Still others are in the boot split phase, which means the panicle’s growth has caused the boot to split apart, and a few plants are starting to pollinate. It appears the field is reaching 50 percent heading which is a good time to decide about a fungicide application for sheath blight and rotten neck blast.
Four stages of maturity area shown, with boot splitting on the left and a fully headed plant at far right.

Dr. Richard Dunand, LSU AgCenter plant physiologist at the Rice Research Station, estimates the field is 5 weeks from harvest.

Dunand said the rice plants that experience less fertilizer enters the heading stage earlier. That often happens on the edges of a field, which happened at the blog field, where pilots have to negotiate around power lines or where the field elevation is higher, causing a shallower flood that makes for less efficient nitrogen availability. The edges of drill-seeded fields are sometime ‘dressed up’ with an extra drill pass or two around the perimeter of the field. When this occurs as it has in the blog field, stand (plant population) is high. The stand may have a higher plant population on the edges of a field, and with a dense plant population, competition between plants can lead to slightly earlier maturity. Dunand said he suspects each of the situations above contributed to why the borders of this field are showing earlier maturity.

Below is a photo of plants taken from the field that shows the varying growth stages. The plant on the left has the panicle splitting the boot, while the plant second from the left shows the panicle emerging from the boot. Far right is a fully headed panicle with florets starting to appear on the top of the plant for pollination.

Panicles continue growth

The rice crop in the blog field is growing well, and it is approaching the stage that signals the window for spraying a preventive application of fungicide to protect the field against cercospora.
Last year, the fungal disease wreaked havoc on rice across Southwest Louisiana in the weeks just before harvest, so farmers are on guard against it this year.
Dr. Richard Dunand, LSU AgCenter plant physiologist at the Rice Research Station, dissected several plants in the field Wednesday and found the developing panicles ranging from 2 to 4 inches. Dunand said the consensus is that fungicides intended to fight cercospora should be applied when the average panicle reaches 4 inches. He said that means several plants should be examined to get a good overall survey of a field because plants mature at a different rate, perhaps by as much as a week to 10 days depending on the field.
Larry White, manager of the seed program at the LSU AgCenter Rice Research Station, said Dr. Don Groth, LSU AgCenter plant pathologist at the Rice Research Station, will make a recommendation on what day to apply a fungicide and which chemical to use. But the application by airplane could occur within the week.
Below is a panicle that has grown to 2.5 inches long (almost 6.5 centimeters). The individual florets are developing which will become the reproductive parts of the plant, with each floret, after pollination, becoming a grain of rice.

Meanwhile, Larry is pumping water on the rice field, since it hasn’t rained at the station since Saturday night’s 1-inch downpour.

Panicle differentiation

Rice plants in the blog field have started to reach panicle differentiation, according to Dr. Richard Dunand, LSU AgCenter plant physiologist.

This morning, Dr. Dunand dissected a plant and found that the panicle is just beginning to be visible at about an 1/8 of an inch, as shown in the picture below. The panicle is the small brushy structure on the end of the dissected stem.

It is from the panicle that small flowers, called florets, will develop and eventually become grains of rice as the reproductive phase of growth progresses.

More rain appears possible today. The last moisture recorded at the Rice Research Station was on Tuesday, with 1.07 inches.

Conditions ripe for disease

The wet, humid weather of the past few days in Southwest Louisiana have enhanced conditions for disease on rice. (The rain gauge Friday morning showed .08 inches of rain in the past 24 hours, and rain is possible today. The previous day’s total was 1.9 inches.)
“This is going to bring it on,” said Dr. Don Groth, LSU AgCenter pathologist at the Rice Research Station. “This is perfect weather for disease.”
He said the blog field showed some potential signs of narrow brown spot caused by the cercospera disease. Up to five fields in the area are showing signs of Cercospora, but lab tests are needed to confirm its presence, he said.
The photo at right shows the narrow lesions that Groth, pictured above, suspects are caused by Cercospora.
This isn’t the only disease to worry about, however.
“Everything that keeps that canopy wet is perfect for sheath blight,” Groth said.
The window for spraying fungicides is quickly approaching. He recommends waiting until rice is between the mid-boot stage to 50-75 percent heading before making an application. Even though some signs of disease are showing up, he said, it’s best to wait for that time frame to get optimum effectiveness. For the blog field, Groth estimates the best time to spray will be in late June.
The blog field’s low seeding rate (42 pounds per acre) means the canopy isn’t thick yet, so that will slow down disease development, Groth said. But it will be treated with fungicides anyway because the field is being grown for seed rice.
He said Quadris is usually in the fungicide regimen, but this year Quilt or Stratego will be used because both chemicals contain propiconazole which is effective on Cercospora.
“The fungicides are already ordered and the plane will be here at the appropriate time,” he said.