[Crop Note] current corn stage, physiological maturity (20 Sep 2023) at Champaign in IL, USA
© 2022 – 2023 https://agronomy4future.com
[Crop Note] current corn stage, R6 (12 Sep 2023) at Champaign in IL, USA
Now, corn is progressing toward maturity, currently at the R6 stage, known as Physiological Maturity. This marks the final stage of kernel development, and the corn growth stages are indicated as follows: [Note 1] Corn growth stageR1 – Silking Stage:This stage marks the beginning of reproductive growth. The tassel at the top of the corn plant releases pollen and silks emerge from the ear shoot and catch the pollen to facilitate fertilization. Silks turn brown and dry as fertilization occurs.R2…
A Stroll Through Champaign’s Vibrant Autumn Cornfield
[Crop Note] current corn stage (09 Aug 2023) at Champaign in IL, USA
Around 24 to 26 days after silking, the milky inner fluid (the starchy liquid) within kernels attains a dough-like consistency. At this stage, kernels contain approximately 70% moisture and achieve about 30 to 50% of their mature dry weight. Four embryonic leaves also form during this phase. Once the kernels reach the dough stage, the likelihood of kernel abortion decreases significantly. This suggests that the critical period for determining the number of kernels becomes less relevant after the R3 or…
Investigating Patterns of Nitrous Oxide Emissions in Corn Agriculture
Nitrous oxide (N2O) emissions in agriculture primarily come from the microbial processes of nitrification and denitrification in the soil, and they’re strongly influenced by nitrogen management practices, particularly the use of nitrogen fertilizers. □ Why Crops Cannot Directly Utilize Atmospheric Nitrogen (feat. Nitrogen Cycling in Soil)? ■ Nitrification: The microbial process in which ammonium (NH4+), a form of nitrogen that’s often applied as fertilizer, is converted into nitrate (NO3-). This process can result in the production of nitrous oxide as…
[Crop Note] current corn stage (19 July 2023) at Champaign in IL, USA
Today I visited another corn field in Champaign, Illinois to collect gas samples. The corn growing stage is mostly in R1 stage, but I saw some corns reached to R2 stage. After R1 (silking) stage, the period to determine kernel number has gone, and new period is here. It’s kernel weight. Approximately 12 days after silking, silks become dark, and will dry out rapidly over time. In this stage, the developing kernels are white “blisters” (resemble a blister) on the…
[Crop Note] current corn stage (17 July 2023) at Champaign in IL, USA
Now, the current growing stage is R1, and most of the fertilization is finished. Silks change color and become brown. Silks begin to elongate around the V12 stage. It starts from the ovules near the base of the corn cob and then develops sequentially from the base to the top. Silking of the tip ovules is the last to develop, indicating that the silks from the base of the cob would emerge first from the husk leaves. In other words,…
[Crop Note] current corn stage (03 July 2023) at Champaign in IL, USA
On this very hot day, I took part in sampling greenhouse gas (GHG) emissions in a corn field. The corn plants are currently in a growth stage between V11 and V12. Today marks 68 days since the planting date. Typically, after 6 weeks from emergence, corn is known to be in the V12 stage. However, variations can occur due to weather conditions, varieties, and other environmental factors. In this case, since the estimated emergence is expected within a maximum of…
[Crop Note] current corn stage (27 June 2023) at Champaign in IL, USA
Today, I visited another cornfield near Champaign, IL. The current growing stage is between V10-V11. Every time I go to a cornfield, it’s my interest to identify the V5 leaf. found one corn plant near V8 and dissected it to see nodule formation. This is an interesting activity. We conducted gas sampling. This gadget can measure the emissions of carbon dioxide, nitrous oxide, ammonia, and methane.
Corn growing stage: V6 – V8
The growing point and the tassel go above the soil surface around the V6 stage. The number of kernel rows is being determined from V7 to V8. The stalk begins to elongate. Also, you can see the corn tassel.
[Crop Note] current corn stage (26 June 2023) at Champaign in IL, USA
The current growing stage in Champaign, IL is between V9 and V10. Today is a cloudy day, and it rained for a very short time. Tasseling is currently occurring, and it’s near the 11th node. Today, we collected gas samples. This machine can measure emissions for carbon dioxide (CO2), nitrous oxide (N2O), ammonia (NH3), and other gases at once. It took 4 minutes per spot. © 2022 – 2023 https://agronomy4future.com
Method for Calculating Corn Yield (Mg/ha) from Experimental Field Data at Plot Level
There is a corn experimental field as shown below. While regular corn farmers typically sow the entire field at once without dividing it into plots, researchers divide the field into plots and differentiate treatments to derive experimental results. The yield data obtained from field experiments should be in the common unit used by farmers, which is Mg/ha or bu/acre. However, our experimental field is not as large as a hectare (ha). Even if a certain experimental field is as large…
Corn Development Stages- R4 (Dough)
Around 24 to 26 days after silking, milky inner fluid (the starchy liquid) in kernels becomes a dough-like consistency. Kernels contain around 70% moisture and reaches around 30 – 50% of mature dry weight. In this stage, four embryonic leaves have formed. When kernels have reached dough stage, kernel abortion is much less likely to occur, indicating the critical period to determine kernel number is less relevant after R3 or R4 stage. On the other hand, the critical period to…
How much nitrogen is lost when applying in season?
How much fertilizer do farmers lose when they apply nitrogen in season? Is volatilization a significant problem? Could 4R nutrient management and urease inhibitors help? To answer those questions, our research team had an interview with RealAgriculture in Canada. ArticleCorn School: How much nitrogen is lost when applying in season?
Corn Development Stages- R3 (Milk)
After 18 – 20 days from R1 stage, the kernels become mostly yellow and contain “milky” white fluid (i.e. starch accumulates). However, moisture content of kernel at R3 is around 80%. Starch accumulation continuously occurs in the endosperm, and cell division of endosperm is almost complete, indicating that growth of kernels since R3 would be mostly due to cell expansion and starch accumulation rather than cell division of endosperm. It also means that potential kernel size would be finally determined…
Corn field by drone
This is our corn field for split N experiment in University of Guelph. Video recording by drone @ Guelph, Ontario in Canada.
Corn Development Stages- R2 (Blister)
I harvested some corn plants at R1 stage 12 days ago. Around R1 stage, final kernel number would be determined. In corn, kernel row number (girth) and number per row (length) in an ear are main yield components. Girth determination of the uppermost ear (the ear harvested) begins shortly after the ear shoot is initiated (V5 to V6) and is thought to be complete by growth stage V12, while the potential number of kernels per row (length) is finally determined…
Corn Development Stages- R1 (Silking)
In corn, R1 stage (silking) is one of the most critical period to determine yield potential. The emergence of silk is regarded as the initiation of reproductive period. Each ovule (potential kernel) on the ear develops its own silk (as the stigma of the female flower). Silks initiate to elongate around the V12. It stars from the ovules near the base of the corn cob, and then sequentially developed from base to up. Silking of the tip ovules are lastly…
Current corn stage (28 July 2022) at Guelph in Ontario, Canada
Sowing date: 12/05/2022 Today: 28/07/2022 (78 days from sowing) Current stage: R1 Site: Ontario, Canada Finally corn reached to R1. Now we can see corn silk will appear. Also, we regard corn developmental stage as R1 (silking) when tassels appears. It’s very important silking and tasseling are synchronized timely for successful pollination and fertilization (It would determine final yield). Environmental stresses (i.e. drought or heat, etc) would cause unsynchronization between silking and tasseling. When one appears first and another one…
Different developmental stage of corn ear
This post is the summary of the article, ‘Ear Initiation & Size Determination in Corn’ by prof. Bob Nielsen in Purdue University, and therefore all storytelling in this post is based on the article. In a corn plant, kernel number of per ear (KN) is an important contributor to the grain yield potential. Therefore, developmental stage of corn ear is the critical period to determine KN. Environmental stress during ear development may limit the potential ear size, and therefore final…
Current corn stage (19 July 2022) at Guelph in Ontario, Canada
Sowing date: 12/05/2022 Today: 19/07/2022 (69 days from sowing) Current stage: V13-V14 Site: Guelph, Ontario, Canada Now corn is reaching to VT. Sooner or later, tassels will come out and also corn silk will appear. Now it’s so drought. When corn goes through drought stress, they roll up leaves to protect water loss. So, when you stand in corn field, you can see upper leaves look like sharp. Lower leaves start to be senescent.
Current corn stage (19 July 2022) at Guelph in Ontario, Canada
Sowing date: 30/04/2022 Today: 19/07/2022 (81 days from sowing) Current stage: R1 Site: Guelph, Ontario, Canada Corn variety which was planted at the end of April reached R1 stage.
Current corn stage at Guelph in Ontario, Canada
Sowing date: 12/05/2022 Today: 28/06/2022 (61 days from sowing) Current stage: V7-V8 Site: Guelph, Ontario, Canada Today is 61 days from sowing corn in Guelph. The current stage of corn is between V7 and V8. From now on, the demand of nitrogen in corn will be increased. Therefore, it would be important to track down the current stage of corn continuously. Agronomy study is always fascinated!!