Tillering usually starts when plant has leaves. After the wheat plant finishes forming tillers, it begins elogation of its internodes or the stem extension stage of growth. Most short season wheat will typically produce leaves on the main stem before stem elongation occurs.
The boot stage begins when the head begins to form inside the flag leaf. Next is heading where the head will fully emerge from the stem. After this take places, the plant starts reproductive growth or flowering. Pollination is normally very quick, lasting only about three to five days. Wheat is self-pollinated and it is during this time that kernels per head are determined by the number of flowers that are pollinated. There are some seed treatments available that will protect the early growth of the wheat plant against certain fungal diseases as well as against insect predation.
Once the yield potential is established we need to protect the crop to ensure that we reach our maximum possible yield. The optimum timing for foliar application of fungicides in cereals is from the start of stem elongation to ear emergence. This period coincides with the emergence of the four most important leaves in the crop and the ear. The leaves are the factories that convert sunlight and CO2 into yield, so any disease that reduces either the number of leaves or reduces the area available for photosynthesis will reduce the potential yield.
It is also important to remember that leaves that have not emerged at the time of the application will not be properly protected and it might be necessary to do a second application. Our aim should be to keep the plant as healthy as possible to ensure that we maximise our potential yield as well as maintaining that potential yield.
Be sure to walk through your crops as often as possible so that you can be pro-active and not reactive in managing your wheat crop. For more information, send an email to johannst elsenburg. Search Keywords: Article Theme: All Before answering the million-dollar question, we want to give you a more in-depth definition of a few essential terms.
Vernalization is the process where winter wheat develops the capacity to become a reproductive plant triggered by moisture and a period of cold temperatures. The hardening off period begins in the fall once temperatures at the crown growing point, generally placed about inches below the ground surface level drop below 48 degrees Fahrenheit and continues as the temperature decreases.
This process reduces moisture content in the crown's cells, which slows growth processes and the accumulation of soluble carbohydrates, all of which help the plant resist frost damage.
This will also trigger physiological processes in the plant that allow it to enter reproductive stages produce seed. Without the cold period, winter wheat will remain in the vegetative growth stages and never produce seed.
This can occur weeks after emergence, but in Michigan it often happens before emergence as soon as the seed imbibes water and is exposed to cold temperatures. Emergence is not the same as germination. Wheat germination happens below the ground surface level and starts when the seed absorbs water and ends with the radicle's appearance.
On the other hand, the emergence of wheat is when the seedling breaks through the soil surface, and it is affected by air, soil temperature and seeding depth. For seed planted 0. By Feekes 6. Sufonyl-urea herbicides are safe at this growth stage, but for practical reasons, weed control should have been completed by now. Small grains can still show good response to N topdressing at this time.
This stage is characterized by the rapid expansion of the head and a second detectable node. Look for the presence of two nodes—one should be between 1. These nodes are usually seen as clearly swollen areas of a distinctly different darker shade of green than the rest of the stem.
Note: the upper node may be hidden by the leaf sheath; you may have to run your fingers up the stem to feel for it. If only one node is present, then your wheat is still at Feekes Growth Stage 6. Wheat will still respond to N applied at Feekes 7. This growth stage begins when the last leaf flag leaf begins to emerge from the whorl Figure 4. This stage is particularly significant because the flag leaf makes up approximately 75 percent of the effective leaf area that contributes to grain fill.
It is therefore important to protect and maintain this leaf heathy free of disease and insect damage before and during grain development. When the flag leaf emerges, three nodes are visible above the soil surface. To confirm that the leaf emerging is the flag leaf, split the leaf sheath above the highest node.
If the head and no additional leaves are found inside, Stage 8. This decision should be based upon the following considerations:. If a positive answer applies to the first three questions, and a negative response to the last, plans should be made to protect the crop from further damage.
Check product labels and apply as soon as possible. In most situations, the greatest return to applied foliar fungicides comes from application at Feekes Stages 8 through Nitrogen applications at or after Feekes 8. Moreover, additional N may increase the severity of some foliar diseases, particularly the rusts.
Stage 9. From this point on, leaves are referred to in relation to the flag leaf i. After the flag leaf emergences, army worms can seriously damage yield potential. At the boot stage, the head is fully developed and can be easily seen in the swollen section of the leaf sheath below the flag leaf Figure 6.
This is another important growth stage for making fungicide applications for foliar disease management, particularly late-season diseases such as Stagonospora leaf and glume blotch and rusts. Heading marks the emergence of the wheat head from the leaf sheath of the flag leaf, and is subdivided into stages based on how much of the head has emerged. Stage Wheat is self-pollinating. Most florets are pollinated before anthers are extruded.
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