NDSU Soybean Iron Chlorosis Scores Available

Aug 25, 2021

North Dakota State University conducts research annually on soybean varieties for their tolerance to iron deficiency chlorosis (IDC).

“This information can help producers select soybean varieties for 2022 that are more tolerant to IDC, when needed,” says Hans Kandel, NDSU Extension agronomist.

During the summer of 2021, NDSU’s soybean breeding program tested 205 Enlist, GT27, Roundup Ready and Xtend soybean varieties, as well as 41 conventional and Liberty Link varieties, for IDC tolerance.

The test results are based on replicated trials conducted at a location with a history of IDC. Visual ratings were made on a 1 to 5 scale, with 1 indicating no chlorosis and 5 being the most severe chlorosis. Ratings were taken at three different soybean growth stages.

This summer’s tests showed significant differences among soybean varieties. For example, the average scores for the genetically modified organism (GMO) group tested ranged from 1.1 (most tolerant) to 4 (the least tolerant variety).

The test results are available at https://www.ag.ndsu.edu/varietytrials/soybean.

“Soybean varieties have genetic differences in how tolerant they are to IDC symptoms,” says Carrie Miranda, NDSU soybean breeder.

“Although we had dry growing conditions. IDC was still observed in many soybean fields in eastern North Dakota and northwestern Minnesota during the 2021 crop season,” Kandel says.

Plant leaves with IDC show symptoms of yellowing with green veins. Yellowing, browning and stunting of the plants during the early plant growth usually results in reduced soybean yields.

“Producers can utilize the NDSU data to select for an appropriate IDC-tolerant soybean variety for a field with known IDC issues for their 2022 season,” Miranda says. “Selecting a soybean variety with tolerance to IDC is an important management decision producers can make to reduce the negative yield effect of chlorosis.”

Although IDC tolerance in soybean varieties is important, producers are encouraged to look at the yield potential of soybean varieties as well as other important traits. Varieties with similar IDC tolerance can vary greatly in their yield potential.

Source : ndsu.edu

Video: Wheat Yields in USA and China Threatened by Heat Waves Breaking Enzymes

A new peer reviewed study looks at the generally unrecognized risk of heat waves surpassing the threshold for enzyme damage in wheat.

Most studies that look at crop failure in the main food growing regions (breadbaskets of the planet) look at temperatures and droughts in the historical records to assess present day risk. Since the climate system has changed, these historical based risk analysis studies underestimate the present-day risks.

What this new research study does is generate an ensemble of plausible scenarios for the present climate in terms of temperatures and precipitation, and looks at how many of these plausible scenarios exceed the enzyme-breaking temperature of 32.8 C for wheat, and exceed the high stress yield reducing temperature of 27.8 C for wheat. Also, the study considers the possibility of a compounded failure with heat waves in both regions simultaneously, this greatly reducing global wheat supply and causing severe shortages.

Results show that the likelihood (risk) of wheat crop failure with a one-in-hundred likelihood in 1981 has in today’s climate become increased by 16x in the USA winter wheat crop (to one-in-six) and by 6x in northeast China (to one-in-sixteen).

The risks determined in this new paper are much greater than that obtained in previous work that determines risk by analyzing historical climate patterns.

Clearly, since the climate system is rapidly changing, we cannot assume stationarity and calculate risk probabilities like we did traditionally before.

We are essentially on a new planet, with a new climate regime, and have to understand that everything is different now.