Agronomy4future

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…

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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,…

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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.

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…

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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…

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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…

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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…

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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…

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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…

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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.