Published: April 21, 2008 12:07 pm            

Nitrogen ‘fuel’ for plant growth

Technology driver behind better crop yields

It’s all technology when it comes to agriculture these days, according to Jeff Bedwell, extension educator for agriculture with the OSU Extension Center.

“We work with agriculture producers.” Bedwell said. “A lot of what we do is demonstration. We work with producers one on one or in groups and put out what we call demonstration plots so they can see how technology that has been evolved through research might fit in their situation.”

Bedwell and fellow OSU Extension Center agronomy specialist Roger Gribble work to help farmers and utilize technology to help them produce a better crop. Some of this involves more than just agronomy technology. Agronomists have begun to implement elements of modern science.

Some of the work they do helps determine what crops farmers can plant in their geographic locations.

“Things that are developed in one area of the state may not necessary be as good a job in another area of the state,” Bedwell said. “We put that practice to use, and a producer’s management practice or his environment can allow that to sort of play out, so he can see whether or not something is going to work.”

A lot of what they do deals with nitrogen and fertilization. Enrich strips are something of a new technology used in determining how much nitrogen producers should use.

“Nitrogen is like a fuel tank for a plant,” Bedwell said. “If the tank is empty, the plants are not going to do much.”

Bedwell said some years these plants will produce more than the producer anticipates, and some years the plants are not going to have the environmental conditions, such as moisture and temperature, to produce as much as anticipated. The enrich strip provides an amount of nitrogen available that is non-limiting to plants, regardless of the conditions.

“We read the NDVI, which would be the infrared value associated to the amount of green material in the producer practice versus what the Enrich strip says,” Bedwell said. “We compare the NDVI numbers of the Enrich strip to the producer practice to see if that producer needs to add more nitrogen.”

Bedwell said this makes producers more efficient using nitrogen. It gives them an idea of what the crop potential is.

Producers can also benefit economically with this practice. If the environment is not conducive a particular season for extra plant growth, producers can choose not to buy as much nitrogen, which will save them money in the long run.

Before this new technology came along, soil samples were used to determine the fertility availability.

“We would use strictly yield goals and estimate the amount of nutrients that the next crop would need, and we would apply those nutrients accordingly,” Bedwell said. “The only problem with that is the environmental conditions don’t always match up to the fertility we would apply. So, we would basically put some nitrogen out there that we wouldn’t necessarily need.”

Bedwell said there were also years where they did not meet the nitrogen needs because they had better environmental conditions. On the other hand, there were some years producers used all the nitrogen supplied and still needed more.

“This gives us an idea to better match the year to the nitrogen need,” he said.

Gribble said Oklahoma is fairly unique because the state has research studies that are almost 40 years old. He said this has brought producers from all around the country.

“We use radioactive isotopes on nitrogen molecules, so we can track exactly where they are,” he said. “We know exactly where that specific radioactive isotope ends up in the plant.”

Gribble said they were only capturing about 33 percent of the radioactive activity used with the old system. The new system has improved the percentage to about 66 percent of the fertilizer put out there.

“We have it out there in a situation where we can and can’t use it,” he said. “We’re not going to put any more out there than what the environment is dictating to. We would put it out there if the environment is good for plant growth and development.”

The technological use of biological “Glance ’n Go Sampling” has also helped producers in determining whether or not greenbugs in wheat need to be treated. “Glance ’n Go Sampling” is a method of counting the presence of greenbugs on wheat tillers as well as the number of greenbugs mummies, which results from the presence of the parasite wasps. Entomologists have helped producers determine economic thresholds to decide when to treat and when to see whether natural enemies of the greenbug will suppress the increase in population and bring them back to a level wheat can tolerate.

In terms of ethanol production, the extension center has worked with producers through technology to determine whether canola can be grown in certain areas for ethanol production. The program is still somewhat in its infancy, though.

“Canola is a very specialized crop with regards to how you plant it, how you manage it with diseases and insects and, most importantly, how you harvest it,” Bedwell said. “We probably aren’t that good at it yet.”

The North Central Research Station in Breckinridge has the Oklahoma Mesonet System that helps farmers and producers determine the best crops for their locations. The system is used for data collection to provide information on soil and air temperature, moisture accumulation, top soil and sub-soil levels.

“There are one to three stations in every county across the state of Oklahoma,” Bedwell said. “That gives us a good idea of what our last freeze date is, what our first freeze date is, what our soil temperatures are for planting our summer crops like corn and grain sorghum, because those are temperature sensitive crops when you plant them.”

Bedwell said it also gives farmers a good idea of what moisture accumulations are, now that water is getting to be a buzz word topic. He said this lets agriculture experts know the level of human consumption and crop use and what is needed to be utilized for both and each.

Things like radioactive isotopes and molecular biology have come to the agriculture industry through the advancement of modern medical science. Bedwell and Gribble believe scientific technology will only further improve upon what farmers and producers should and should not do or can and can’t produce.

“What is old technology for the medical field is new technology for other industries,” Gribble said.