The Mid-Term Report Card: What does Corn Ear-Leaf Nutrient Analysis Tell Us?

Transcription

1 The Mid-Term Report Card: What does Corn Ear-Leaf Nutrient Analysis Tell Us? Tony J. Vyn 1, I. Ciampitti 2, P. Kovacs 3, K. Chen 1, S.M. Mueller 1, and T. D. West 1 1 Purdue University, 2 Kansas State University 3 South Dakota State University December 13, 2017 Indiana CCA Conference, Indianapolis, IN

2 Modern Hybrids, Stress Tolerance and Nutrient + H 2 O Management?

3 Potential Corn Leaf Nutrient Deficiencies - IN Ear Leaf R1, 3670 samples, six years Nutrient Deficiency threshold 1 Percent of samples deficient 2 < Less Than N (%) < Six year Average 25.5 % P (%) < K (%) < % S (%) < Zn (ppm) < Data: Ceres Solutions, Lafayette, IN, corn ear leaf R1-R2 1 Critical Nutrient level based on: Extension Bulletin E-2567 (New), July 1995 Data source: Betsy Bower, Ceres Solutions Miller, 2017

4 Corn Ear Leaf K Concentration Frequency Plot Observations three years, GS R1-R2 Western Indiana: 1883 samples Deficient 1.90 % K in in in Shifts in ear leaf K distributions with variations in May-June 1 precipitation Data source: Betsy Bower, Ceres Solutions Miller, 2017

5 Whole-plant, grain, cob and stover nutrient (macro- and micro-) determination at maturity

6 Whole-Plant Corn Analysis at the R1 Stage Sampling from field; 2. Weighting fresh weight; 3. Select five sub-sample and separate sub-samples into leaf, stem (with husk), ear-shoot (R1); 4. Chopping; 5. Bagging; 6. Weighting all fresh weights 4 5

7 Timing and Source of N Uptake by Plants and Grain N N N Ciampitti et al., 2013 Agronomy Journal

8 Post-flowering uptake of N,P, K, S in response to plant density and N rates Source: Ciampitti et al., Agron. J.

9 Published online September 7, 2017 soil FertIlIty & crop NutrItIoN Relationships between Ear-Leaf Nutrient Concentrations at Silking and Corn Biomass and Grain Yields at Maturity Péter Kovács* and Tony J. Vyn* In-season assessments of nutrient sufficiency for corn plants following the depletion of seed nutrient reserves has typically involved either whole-plant sampling at early vegetative stages (e.g., V6; Abendroth et al., 2011) or sampling of ear leave at flowering (R1). Early vegetative stage sampling generally permits

10 Critical Ear-leaf Nitrogen Concentrations (R1 stage) for High Yield Corn ( ) Kovacs and Vyn, Agronomy J., 2017

11 Nitrogen Concentrations in Ear-leaves versus all Leaves during Critical Period in Corn (Wanatah, 2015) Ear Leaf N Concentrations around R1 Minus 14 days R1 plus 4 R1 plus 14 days Nitrogen Rate (pounds/acre) applied at V4 Ear-leaf N % is sampling time sensitive around R1, and is higher than all leaves All Leaf N Concentration Change over Time Minus 14 days R1 plus 4 R1 plus 14 days Nitrogen Rate (pounds/acre) applied at V4

12 Corn Leaf N Concentration is not the Same as Ear-leaf N Concentration During the Critical Period ( ) Source: Sarah Mueller and T.J. Vyn, unpublished

13 Plant Density Impacts on Leaf Nutrient Concentrations at R1 (Average of 8 hybrids and 2 locations in ) Plant Density N P K Mg % 22,000 pls/ac ,000 pls/ac ,000 pls/ac Higher densities make it more difficult to attain target concentrations. Plant Density Fe Mn Cu Zn ppm 22,000 pls/ac ,000 pls/ac ,000 pls/ac

14 Plant Densities can Impact Leaf Nutrient Concentrations at R1 Stage West Lafayette, IN Wanatah, IN

15 Critical Ear-leaf P, K and S Concentrations (R1 stage) for High Yield Corn ( ) Kovacs and Vyn, Agronomy J., 2017

16 Individual Macro-nutrients are Frequently Related with Each Other

17 Indiana Corn Yield Responses to K 2 O Placement and Timing Tillage System K 2 O timing Aspire K product rate (lb/acre) 2016 yield (bu/acre) 2017 yield (bu/acre) 2-year Mean (bu/acre) No-till NA de 239 cd 232 ef No-till Spring de 252 abc 238 bcde Fall Strip-till NA bcd 242 bcd 235 de Fall Strip-till Fall ab 254 ab 244 abc Fall Strip-till Fall ab 258 a 246 a Spring Strip-till NA e 236 d 227 f Spring Strip-till Spring bcd 257 a 242 abcd Spring Strip-till Spring abc 260 a 245 ab Fall Chisel NA cd 246 abcd 236 cde Fall Chisel Fall a 254 abc 245 ab Soil-Test K mean: 214 ppm. 110 ppm.

18 Ear-leaf K Concentration Relation to Final Yield in Indiana Experiments ( ) Grain Yield (bushels/acre) Earleaf K 2016, Aspire Study, ACRE y = x R² = Earleaf K % Grain Yield (bushels/acre) Earleaf K 2017, Aspire Study, ACRE y = x R² = Earleaf K %

19 Post-silk uptake of Ca, Mg, Fe, Zn, Mn and Cu in response to plant density and N rates Source: Ciampitti et al., 2013, Agronomy Journal

20 Leaf Micronutrient Concentration (Zn and Mn) Relationships at R1 to Final Grain Yield

21 Leaf Micronutrient Concentration (Cu and Fe) Relationships at R1 to Final Grain Yield

22 Later-stage Foliar Application of Macro-Nutrients and Micro-Nutrients? Photo Sources: 360 Yield Center

23 Corn biomass and nutrient accumulation at three N rates for a population of 32,000 plants/acre Source: Ciampitti et al., Agronomy Journal 2013.

24 Certain Negative Nutrient Concentration Relationships Between Nutrients Are Expected

25 Merits and Challenges of Corn Ear-leaf Sampling at R1 1. Ear-leaf sampling provides a more accurate assessment of inseason plant nutrient availability than soil samples. 2. Ear-leaf concentrations are an important benchmark of plant response to nutrient management at a critical stage. 3. Higher concentration minimums may be needed for modern hybrids for nutrients like K, S, Cu and Fe. 4. Higher plant densities make these higher leaf nutrient concentrations more difficult to achieve. 5. It is important to recognize the dependent relationship between individual nutrients (e.g. certain secondary cations). 6. One difficult challenge to achieve is to get the sampling done as close as possible to the actual silking date. 7. This mid-term report card is too late for corrective action in certain nutrients (like K), but is always helpful for longer-term nutrient management.

26 Acknowledgments Funding: Indiana Corn Marketing Council Dupont-Pioneer Dow AgroSciences (2009- ) 4R Nutrient Stewardship The Mosaic Company Monsanto Company Equipment: John Deere Cropping Systems Unit Seed: Pioneer Hi-Bred, Int l. Monsanto Dow AgroSciences

27 Questions?

28 What About Late-Season N? Photo by Mike Shuter, 2014

29 Surface application of UAN at 45 kg ha -1 rate

30 Conclusions There has already been considerable gains in NUE over time in maize production systems. Those gains have come about because of the combination of genetic, fertilizer practice, and crop management improvements over time. There are significant challenges ahead in achieving continued NUE improvements but those are best addressed in more coordinated (multi-lateral) and systems-level research. Research partnerships with other scientific disciplines and with fertilizer industry and grower plus non-profit organizations need to be expanded.