Read The Signs Of Nutrient Deficiency

Phosphorus Deficiency in Corn

Throughout the growing season, crops may exhibit unusual coloring, stunted growth and leaf damage or defoliation. Often these visual symptoms are due to nutrient deficiencies, which reduce yields, crop quality and ultimately producer profitability. By recognizing visual symptoms during the growing season and pinpointing production issues before harvest, growers can make plans for post-harvest steps that will help prevent similar issues with subsequent crops.

“Nutrient deficiency symptoms can be anything from leaf yellowing and leaf loss to twisted ears with irregular kernel rows and imperfectly developed ear tips. Even stalk lodging can be a symptom of nutrient deficiency,” explains Matias Ruffo with The Mosaic Co.

In previous years such as 2010 and 2011, yellow or purple corn in the spring was often blamed on cool, wet soils. Generally, growers could wait for warmer temperatures for the crop to recover.

“2012 has given most of the Corn Belt an unusually warm and dry spring,” says Ruffo. “That may mean less discolored corn, and may also present a better opportunity to visually scout for areas of nutrient deficiency. If corn is discolored this year, chances are it’s something other than the weather.”

Ruffo says the flipside of the benefits of a warm spring can be overconfidence. It would be tempting to look at green, apparently healthy, corn this year and automatically assume no nutrient deficiencies exist. But that assumption could prove costly in lost yield this season and in the future. Once a deficiency symptom appears, some yield, and perhaps quality, may have already been lost.

Comprehensive Balance

Nutrient deficiencies are widespread and scattered across the Corn Belt. In 2011, soil testing results from A&L Great Lakes Laboratories showed the most common secondary and micronutrient deficiencies were sulfur (S) and zinc (Zn), with most Midwestern states showing a high percentage of low soil test ratings for both nutrients. (Results may be viewed here under customer tools, soil test summaries.)

According to Ruffo, getting a balance of all the nutrients, not just the amount of nitrogen (N), phosphorus (P) and potassium (K) in the soil impacts corn’s ability to utilize soil fertility.  

“Your soil test may indicate adequate N, P and K, but a deficiency of S or Zn can reduce corn’s ability to take up and utilize those nutrients,” says Ruffo. “Leaf tissue testing might even show high concentrations of P, but inadequate S or Zn could be inhibiting the corn plant’s ability to use P to produce yield potential.”

Nutrients all impact one another in the plant, which is why balanced fertility of all nutrients is so important. And why Mosaic has developed fertilizer products such as MicroEssentials SZ, in which S and Zn are added in partial layers around phosphorus-based fertilizer particles. The result is uniform, nutritionally balanced fertilizer granules, each with essential nutrients combined in precisely the correct ratio for plant health.

Trust The Test

Don’t try to outsmart the soil test. Gyles Randall, professor of soil science at the University of Minnesota, has noted that low soil test P can be particularly costly to yield when growers try to mine the soil for short-term input cost savings. Nevertheless, some growers will try to save input costs.

“There have been efforts to use leaf tissue analysis to determine a corn crop’s nutrient needs,” says Randall, “but tissue testing is a complicated method with shortcomings, so should not be used as a sole indicator of determining the amount of soil nutrients necessary compared to soil testing.”

The nutrient content of a corn leaf is highly dependent on when the leaf sample was taken — the smaller the plant, the higher the concentration. Additionally, plant growth phase and timing of fertilizer application will affect the leaf tissue results.

Randall says plants initially may not show obvious symptoms of deficiency other than slower growth. But even a mild deficiency or fertility imbalance can disrupt essential plant metabolic processes. Since deficiencies rarely occur uniformly across an entire field, crops may mature unevenly, leading to less yield, harvesting difficulties and lower quality of the harvested product.

Randall’s research has shown significant yield benefits from adding more P (25 to 50 pounds per acre) to the soil when soil tests show a low P level of seven parts per million (ppm). Very high soil P-test soils (25 ppm) showed no yield benefit (or loss) from adding additional P.

What Tissue Testing Teaches

While tissue testing is no guarantee of adequate soil fertility, it can be a good way to red-flag fields, or areas of fields, for potential nutrient deficiency problems.

Bob Deutsch with AgVise Labs notes that plant tissue tests across North Dakota, South Dakota and Minnesota showed an average of more than 25% of all corn tissue samples below the critical level for N, P, K, S and Zn. Much of that could be due to soil variability across individual fields, or to the fact that in some cases, growers requested tissue tests of plants already showing visual deficiency symptoms.

“The corn data indicates we had a significant number of fields testing low in N, P, K, S and Zn,” says Deutsch. “The large number of corn fields testing low in N may be partly due to the loss of N during above-normal precipitation events, causing leaching and denitrification.”

Wheat data indicates many of the same trends as corn. The high number of wheat fields testing below the critical level in Zn was somewhat surprising. This low number may be due to the fact that we are receiving large volumes of plant tissues from areas where Zn has never been applied.

“We need to be aware we have nutrient issues on corn and wheat in our area with the three major nutrients of N, P and K,” Deutsch continues. “We also have issues with secondary nutrients of sulfur and chloride and the micronutrients zinc and copper.” Deutsch indicates these micronutrient issues could be addressed with products like MicroEssentials.

Leave a Reply

Fertilizer Stories

FertilizerFall Fertility 2014: Forecasting Fertilizer Use
September 7, 2014
Great crops this year have tapped the soil, and fall work is definitely called for, but how challenging will that get? Read More
Aerial view of the West Fertilizer explosion site
FertilizerFertilizer Companies Blame City For West, TX, Explosion
August 6, 2014
El Dorado Chemical Co. and CF Industries contend the city failed to properly train the first responders and had insufficient protocols in place to battle the April 17, 2013, blaze at West Fertilizer Co. that triggered the explosion. Read More
FertilizerThe Fertilizer Institute: New President, Renewed Energy
February 3, 2014
Chris Jahn relishes the opportunity to lead the organization through the challenging times ahead. Read More
FertilizerA New Cycle For Fertilizer Demand
January 2, 2014
Changes in the corn market could have a major impact on the crop nutrients sector in 2014, say experts. Read More

Trending Articles

Matt Hopkins15 Best New Agriculture Apps Worth Downloading In 2014
December 16, 2013
These latest agriculture apps are sure to help ag professionals do their jobs more efficiently in 2014 and beyond. Read More
Seed/BiotechMonsanto Offers New Support For Ferguson, Area Communities
October 8, 2014
Monsanto Co. has committed $1 million in new support for several collaborative efforts in Ferguson, MO, and surrounding communities in North St. Louis County. Read More
Seed/BiotechUnapproved Genetically Modified Wheat Found In Montana
October 3, 2014
USDA reports that one year after discovery of Monsanto's unapproved wheat in a single Oregon field disrupted U.S. wheat export sales, the GMO wheat has again been found in Montana. Read More
Equipment2014 Product Of The Year Voting
September 19, 2014
The deadline to vote for the 2014 CropLife IRON Product of the Year is October 31. Please cast your vote today to help us determine the winner. Read More
FertilizerFall Fertility 2014: Forecasting Fertilizer Use
September 7, 2014
Great crops this year have tapped the soil, and fall work is definitely called for, but how challenging will that get? Read More
CropLife 100CHS To Build $3 Billion Fertilizer Plant In North Dakota
September 5, 2014
The fertilizer plant in Spiritwood will be the single largest investment in CHS history, as well as the single largest private investment project ever undertaken in North Dakota. Read More

Latest News

ManagementGreenfield Scholars Program Aims To Sustain Agronomy Wo…
October 21, 2014
The program encourages talented students to study agronomy, crop and soil sciences while cultivating networks to develop the necessary workforce to sustain the profession. Read More
Paul SchrimpfPrecision Ag: Taking It To The Hill
October 21, 2014
A new coalition took the good news message of precision agriculture to Washington, DC, last month. Read More
ManagementUSDA Awards $18 Million In Small Business Research Gran…
October 21, 2014
The grants will provide high quality, advanced research and development that will lead to technological innovations and solutions for American agriculture. Read More
FertilizerCF Industries Terminates Merger Discussions With Yara I…
October 21, 2014
CF Industries Holdings and Yara International have terminated their discussions regarding a potential merger of equals transaction. Read More
Seed/BiotechSyngenta Ranked A Top 10 Biotech Employer For Third tim…
October 20, 2014
Syngenta ranked in the top 10 among the world’s top biotech employers, according to an annual survey conducted by Science magazine. Read More
CropLife 100Wheat Growers Break Ground For New Facility At Kennebec
October 20, 2014
Wheat Growers has broke ground for a state-of-the-art shuttle loader grain handling, fertilizer and agronomy facility in Kennebec, SD. Read More
FertilizerVerdesian Life Sciences Signs Agreement With Los Alamos…
October 20, 2014
Verdesian Life Sciences has signed a licensing agreement with Los Alamos National Laboratory to develop and market LANL’s latest nitrogen enhancement technology for plants. Read More
MicronutrientsStoller Group Announces Groundbreaking At New Office Bu…
October 20, 2014
Jerry Stoller, founder and president of Stoller Group, announced the groundbreaking at the site of the company’s future headquarters in Read More
Crop InputsBioSafe Systems Opens New Production Facility In Nevada
October 20, 2014
BioSafe Systems has completed construction of a state-of-art production facility in Sparks, NV, for its line of activated peroxygen products. Read More
Crop InputsPlatform Specialty Products To Acquire Arysta LifeScien…
October 20, 2014
Once the acquisition is complete, Platform Specialty Products will combine Arysta LifeScience with previously acquired companies Agriphar and Chemtura Crop Solutions. Read More
Seed/BiotechEPA Approves Dow’s Enlist Duo Herbicide
October 15, 2014
The Enlist Weed Control System, breakthrough technology to fight resistant and tough weeds, has received the long-awaited green light from federal regulatory authorities. Read More
MicronutrientsGypsum On Farms Could Help Keep Water Clean, Not Green
October 14, 2014
Gypsum, which has roots in the past as a farm soil treatment, also may have a bright future, and not just as a booster of crops but also as a protector of water. Read More
Photo credit: The United Soybean Board/The Soybean Checkoff.
Crop InputsVerdesian Grows Sales Staff
October 14, 2014
The new account managers will drive sales growth and support relationships with key customers in the plant nutrition and seed treatment and inoculants product categories. Read More
WebinarsUpcoming Webinars
October 14, 2014
Register for one of our upcoming Webinars or access our archive of past Webinars to view recordings of presentations that may be of interest to you. Read More
CropLife 100The Andersons Purchases Six Grain Elevators, Four Agron…
October 14, 2014
The Andersons has acquired Auburn Bean and Grain of Auburn, MI, which will increase the storage capacity of its Grain Group by about 13%. Read More
StewardshipThree Ohio Ag Retailers Honored With 4R Certification
October 13, 2014
The 4R Nutrient Stewardship Certification Program has announced its first three agriculture nutrient service providers to achieve certified status. Read More
Eric SfiligojEntering Agriculture’s New Phase
October 13, 2014
The market’s giddy ride the past few years might be coming to an end in 2015, warns one industry insider. Read More
Eric SfiligojWar And Green Peace
October 11, 2014
A one-time member of Green Peace recently explained why he left the organization after 15 years. Read More