The Root – The Beginning of the Plant

It is well known that tree roots grow downward, penetrating deep into the soil, exhibiting positive geotropism. However, in the jungles of Venezuela, 12 species
of trees have been discovered whose roots climb up the trunk. The soil in these areas contains so few nutrients that the roots have adapted to absorb calcium,
 magnesium, potassium, and other minerals from the rainwater running down the trunks.

To confirm this hypothesis, researchers artificially increased the mineral content in the rainwater. The upward growth of the roots intensified after this.

Types of Root Systems

The root system of plants can be of two types: taproot and fibrous. Fibrous roots absorb water and mineral salts better than taproots.

The main root is very well developed in gymnosperms and dicotyledonous angiosperms.

Roots Also Breathe

Oxygen plays a significant role in the life of roots. It is necessary for aerobic respiration. However, roots are not always in conditions that provide them with
oxygen. In heavy soils rich in organic matter, the concentration of oxygen sharply decreases, and the content of carbon dioxide increases significantly.
These gas regime conditions are unfavorable for aerobic respiration: anaerobic processes begin, leading to the accumulation of ethyl alcohol, acetaldehyde,
and other substances that are harmful to plant roots. A similar situation is observed when a crust forms on the soil surface.

Marsh plants have intercellular spaces that permeate the entire plant or air tissues through which oxygen from the above-ground parts of the plant reaches
the roots, and carbon dioxide moves in the opposite direction.

It should be noted that in other plants, oxygen also moves from the leaves to the roots. This has been established using radioactive elements. For example,
when the roots of beans, corn, and cotton are placed in conditions of oxygen starvation, the above-ground parts of these plants significantly increase oxygen
 absorption, which then moves to the root system.

On the silted shores of tropical seas, where there is very little oxygen in the soil, mangrove trees grow. Their roots emerge to the soil surface, resembling
stakes driven into the ground – these above-ground parts of the roots are used by the plants for respiration.

Hilling Potatoes

Any loosening of the soil is beneficial for potato roots, as the soil becomes better aerated, and the roots receive more oxygen. Additionally, hilling allows for
more effective weed control and supports the stems in an upright position.

However, hilling potatoes is especially important because:

• When in contact with the soil, the stems can form additional roots, improving the plant's nutrition.

• Potato tubers are modified lateral shoots. Shoots can only form in the leaf axils. After hilling, more leaf axils are found underground, increasing the number
  of potential growth points for lateral underground shoots – tubers.

Potatoes are grown to obtain storage tubers. The Colorado potato beetle eats the leaves and stems of potatoes, reducing the assimilation surface; as a result,
tubers do not form or are very small.

Additional Facts About Roots

1. Roots as Storage Organs: In some plants, roots serve as storage organs for nutrients. For example, in carrots and beets, the root crops accumulate
   a large amount of carbohydrates, which the plant uses during unfavorable conditions.

2. Symbiosis with Fungi: Many plants enter into symbiotic relationships with fungi, forming mycorrhiza. Fungi help plants absorb water and mineral
   substances from the soil, while plants provide fungi with organic substances.

3. Adaptations to Different Conditions: Plant roots can have various adaptations to environmental conditions. For example, in desert plants, roots can
   penetrate to great depths to reach water-bearing layers, while in marsh plants, roots may have air tissues to ensure respiration in high humidity conditions.