Yara Crop Nutrition
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Agronomic Principles
Crop Characteristics
Potatoes produce a fibrous root system. These roots are at best no more than 24in long. Thus potatoes are shallow rooted compared to cereals for example, which can root to at least 47in depth. As a result, potatoes are often unable to exploit nutrients and soil moisture at depth within a soil profile.
While root growth occurs when soil temperatures are between 50 to 95˚F (10 to 35˚C), best, most active root development is at soil temperatures of between 59 and 68˚F (15 and 20˚C).
Leaf (haulm) growth occurs at temperatures of between 44.6 to 86˚F (7 to 30˚C) , but optimal growth is at around 68 to 77˚F (20 to 25˚C). Optimum temperatures for stolon growth are similar.
effects of soil temperature on root development
The potato tuber is an enlarged portion of the stolon. The initiation of this tuber is triggered by short day lengths (photoperiods), and involves growth hormones. The colder the soil temperature, the more rapid the initiation of tubers and the greater the number of tubers formed. The optimum soil temperature for tuber initiation is 59 to 68˚F (15 to 20˚C).
Under these conditions, the potato plant will have short stolons and shoots. Longer day lengths delay tuber initiation and favor the growth of the stolon and shoot. High temperatures also reduce tuber formation. Late varieties seem to be more sensitive to long day lengths or high temperature conditions.
Low nitrogen and high sucrose levels in the plant favor the formation of more tubers.
Once formed, tubers grow rapidly, reaching a maximum rate of up to 1,249 lb/ac/day in temperate climates. See figure below:
potato tuber growth rate, germany
Physiological Aging
By planting sprouted seed, crop growth can be advanced. The magnitude of this response and its effect on increasing crop yield is related to the physiological age of the seed at planting.
Answer:
It reflects the common ancestry of humans with hairy vertebrates.
Explanation:
Evolution is the change in the species with the passage of time. Some species might get extinct and some species might develop the advance character during the evolutionary process.
The evolutionary history of the organisms can be classified on the basis of the paleontological or molecular evidence. The two groups of the organisms can share a common ancestor if they have some similar features with each other. In the given question, it can be concluded that hairy vertebrates and human might have the common ancestor.
Thus, the correct answer is option (a).
A means of water erosion would not be C. natural water springs. Erosion occurs when water or wind removes rock, dissolved material, and soil from one location to another. All the other options describe water moving from one location to another, which accurately describes what erosion does.
Organelles float around in the cytoplasm.
