How to choose the right predecessor in the field, or What is the difference between intensive and extensive corn hybrids?
The choice of a corn hybrid for growing in monoculture or with other predecessors is a topical issue. The best predecessors for corn are cereals and legumes. The worst are sunflower and corn.
It is also necessary to select hybrids for drought resistance and the ability to “respond” to sufficient mineral nutrition. Only after answering these questions can we decide whether we need extensive or intensive hybrids. What is the difference between them?
Yurii Nahornyi, agronomist at the Ukrainian Scientific Institute of Breeding (VNIS):
“Extensive hybrids are less demanding on growing conditions. They tolerate short-term drought better, show better results with minimal nutrition. Intensive hybrids are potentially more productive, but require more care, more moisture, and a better agricultural background. Only under such conditions can we realize their potential.”
Most often, producers from those regions where there are no problems with moisture supply rely on intensive hybrids. According to Yuriy Nagorny, the intensive hybrids in VNIS's portfolio include Paradis, Tor, Gran 6, Amarok 290 and Tesla.
Among them, Amarok 290 (FAO 320) is drought tolerant and adaptable to growing in different soil and climatic conditions, but it shows its full potential with good moisture availability. Last year, it was harvested with a yield of 5-6 t/ha in Kirovohrad region and 15 t/ha in Kyiv region. This hybrid is ideal for both grain and silage use.
But Gran 6 (FAO 300) is stable under different growing conditions and has an extremely fast moisture release. In Mykolaiv region, it showed a yield of 6.5 t/ha, and in Kyiv region - 14.8 t/ha.
Yurii Nahornyi, agronomist at the Ukrainian Scientific Institute of Breeding (VNIS):
“Another of our hybrids, Tesla, can be sown all over Ukraine. It is a cool, plastic hybrid that farmers are very fond of. Although it has FAO 350, it releases moisture very well. In Kirovograd region, it was harvested with a yield of 8.5 t/ha, and in Kyiv region - 15.2 t/ha with a moisture content of 18%. It can be used for grain, silage and biogas production.”
Extensive hybrids are more commonly used by farmers in the South because they are more drought-resistant and yield less than intensive hybrids, but stable. In the VNIS portfolio, these include Gran 310, VN 63, Manticore, and VN6763.
Moisture release and drought tolerance of corn hybrids - why should we pay attention to it?
When describing corn hybrids in their catalogs, seed companies often indicate the level of moisture release. Why? Because this indicator is the ability of the hybrid to release moisture during the ripening period. Of course, it is better to choose a hybrid that would ripen naturally a few days before the cold snap and harvest. Then the company would harvest less moist grain and not spend money on drying.
Yurii Nahornyi, agronomist at the Ukrainian Scientific Institute of Breeding (VNIS):
“VN 63 (FAO 280) releases moisture phenomenally due to the thin cob rod. I'm not even afraid to say that there are very few hybrids with such a powerful moisture release on the Ukrainian market today.”
He also adds that in recent years, moisture has been the main limiting factor in growing corn. That's why he recommends choosing hybrids that will produce stable yields even with insufficient moisture. The Tesla hybrid is characterized by high drought tolerance, as well as hybrids VN 6763, VN 63 and Manticore.
And another property that you should pay attention to when looking through the catalog of seed producers is resistance to lodging. Although modern hybrids show good stability and stem quality, no one has canceled weather surprises. And the harvesting of lodging-resistant hybrids can be extended in time, for example, if the weather does not allow you to enter the field on time.
What about disease-resistant corn hybrids?
The main diseases of corn are blister smut, Fusarium root rot, and Fusarium head blight, says the VNIS agronomist.
Yuriy Nahornyi, agronomist at the Ukrainian Scientific Institute of Breeding (VNIS):
“Blister smut is an insidious disease. The main method of combating it will be the selection of a hybrid resistant to this disease. If there are no weather disasters, for example, hail, it will not appear. Fusarium root rot can be controlled by using seed treatment agents and choosing a resistant hybrid.”
I do No-till, and my neighbor does Strip-till. What hybrids do you recommend?
You need to choose hybrids that have a strong root system. According to Yurii Nagornyi, all VNIS hybrids are suitable for strip-till cultivation. But the hybrids VN 63, Gran 6, VN 6367 and Tesla have proven themselves well in zero tillage technology.
What mistakes do farmers make most often when choosing corn hybrids?
First, they choose the wrong maturity group, as we mentioned at the beginning of this article. Secondly, farmers often think that if they choose intensive hybrids, they will get sky-high yields. But it doesn't work that way. Because they took an intensive hybrid, were not able to give it everything it needed - mineral nutrition, moisture - and it “sank” in yield.
The third, fairly common mistake is sowing hybrids with the same FAO in the same farm.
Yuriy Nagorny, agronomist at the Ukrainian Scientific Institute of Breeding(VNIS):
“When people ask me how to choose a hybrid, I always recommend sowing hybrids with different FAOs in the same farm. One season, some work, the next season, others “shoot”. It all depends on precipitation at a critical time for corn. And so in the fall, the farmer will get an average positive result for himself. Therefore, a hybrid with one FAO is like a lottery.”
Yuriy Nahornyi recommends allocating 25% of the area for hybrids with an early maturity group, 50% for hybrids that best suit the conditions in the region, and the remaining 25% of the fields to crops with higher FAO and later maturity.
The agronomist also points out that corn is a thermophilic and moisture-loving crop, and to get good seedlings, the soil temperature at the depth of the seeds should be +10°C, at least +8°C (but the trend should be towards higher temperatures). Many people neglect this rule and then get weak or no seedlings at all.
What are the criteria for choosing sunflower hybrids?
Maturity group. This is an indicator by which a farm can choose a hybrid, depending on the presence of a certain number of active temperature sums in the region. In simple words, whether the hybrid will have time to dry out in the farm's conditions or not. And whether the farmer will have time to harvest the sunflower before sowing the next crop. For example, if corn or another spring crop is to be sown after sunflower, then hybrids with a longer growing season can be used. If winter crops are to be planted, they should have a shorter one so that the farmer can harvest the sunflower in time to prepare the field for sowing.
In Ukraine, there are five groups of sunflower maturity:
- early ripe - with a growing season of 70-105 days;
- medium early - 105-110 days;
- medium-ripening - 110-115;
- medium-late - 116-120;
- late-ripening - more than 121 days.
Yurii Nahornyi, agronomist at the Ukrainian Scientific Institute of Breeding (VNIS):
“I repeat once again: a farmer should always calculate his strength and technical capabilities, as well as take into account climatic features. If, for example, it is the North and West of Ukraine, where the sum of active temperatures is lower, then late-ripening sunflower will not be suitable for this region. It will snow, and the sunflower will remain green in the field. It is better to use hybrids with a short growing season in these regions.”
It should also be borne in mind that there are intensive sunflower hybrids that require a good agricultural background and sufficient moisture, and extensive sunflower hybrids that are drought-resistant and produce a good harvest even under unfavorable conditions.
What about sunflower diseases?
In recent years, the area under sunflower has increased in our country. Accordingly, the number of diseases in this crop has increased.
For example, 10 years ago, fungicides were just being talked about and in most cases, few people applied them, and if they did, it was only once. At the moment, the situation has changed dramatically - with the increase in sowing areas, the number of diseases on the crop has increased (as mentioned above). And sometimes it is impossible to get good yields without applying a good fungicide. At the moment, sunflower requires at least two fungicide treatments.
We should also not forget about the resistance of hybrids to various pathogens. After all, there are diseases such as downy mildew and various forms of sclerotinia, which are difficult to control with fungicides. VNIS breeders are working to develop sunflower hybrids that have genetic resistance to various diseases. We already have such hybrids in our portfolio. These are Mastak, Magnum, Karlos 105, Folk, Vegas, Almera and others.
Do I want to grow high oleic sunflower? How to choose a hybrid?
The principle of selection is the same as for classic sunflower: maturity group, herbicide technology, resistance to broomrape, hybrid intensity. But preference should be given to certified producers and look at the oleic acid content - this figure should be above 82%. And remember that growing high-oleic sunflower requires spatial isolation - at least 300 meters from the field with conventional sunflower to avoid cross-pollination.
What are the most common mistakes farmers make when choosing sunflower hybrids?
Improper selection of a hybrid for their soil and climate zone. Yurii Nahornyi advises to consult with seed producers who will help you choose the right hybrid. After all, intensive hybrids “burn” in the South, and late-ripening ones do not have time to dry in the West.
Resistance to broomrape. Farmers believe that if there hasn't been sunflower on their fields for 10 years, they don't have broomrape. In fact, there may be no sunflower on the field, but the broomrape has been there for a long time. After all, it is able to parasitize on weeds, be carried by wind and machinery.
Incorrectly selected cultivation technology. If the field is infested with perennial weeds, the classical technology will not help. There are very few insurance and selective herbicides for classic hybrids. Therefore, it is necessary to select the sunflower technology depending on the soil and climatic characteristics of the farm, as well as on the type of weeds on the field.
Yurii Nagorny, agronomist at the Ukrainian Scientific Institute of Breeding (VNIS):
“Another common mistake is sowing too early. For some reason, farmers think that if sunflower is a more cold-resistant crop than corn, then it should be sown as soon as the snow melts. This can be afforded by farmers in Odesa region, those engaged in agricultural production in Izmail and Bilhorod-Dnistrovskyi districts, where the temperature is already +10-15°C in March. However, I recommend that farmers in the North and West wait for the warmth.”
So, choosing the right hybrid for your farm is not an easy task and you need to approach it with a clear head. As you can see, you need to take into account not only the genetic potential of the hybrid, but also your soil and climatic conditions, the agro background of the field and technical capabilities.