Thursday, August 18, 2011

TAP ROOT SYSTEM



A Taproot System derives directly from the first root that emerge from a seed (the radicle or primary root) that enlarges and forms a prominent central root that is called the taproot. The taproot is larger in diameter than the lateral roots. Lateral roots branch off from the taproot, and subsequent lateral roots can branch off other lateral roots. Taproots generally grow more deeply into the soil than do fibrous roots. It often become a modified storage organ for food reserves such as carbohydrate or for reaching water deep in the ground. This article write of one of the plants important components that was TAP ROOT based on few readings and my own knowledge.


A taproot system, generally found in Dicotyledons and conifers. Most trees begin life with a taproot, but after one to a few years change to a wide-spreading fibrous root system with mainly horizontal surface roots and only a few vertical, deep anchoring roots. A typical mature tree 30-50 m tall has a root system that extends horizontally in all directions as far as the tree is tall or more, but well over 95% of the roots are in the top 50 cm depth of soil. A tap root is a specific type of root structure present on some plants, which is typified by being rather large, and going directly down into the ground. The tap root has other roots growing off of it as it descends, acting as a sort of trunk beneath the ground. Plants with a tap root can be contrasted with plants that have a fibrous root system.


There are a number of ways in which a tap root can be beneficial to a plant. One of the most important is that it allows the plant to reach down quite far to find water to sustain itself. In drier climates, or areas where water tends to run deep, this can be incredibly useful. Indeed, many desert plants have incredibly well-developed tap root systems, allowing them to survive in even the most arid of climates. Mesquites, for example, have adapted to survive in the Mojave Desert, and so have come up with many biological tools to help them reach and conserve water, including a tap root that can reach lengths of more than 80 feet (25m). In many plants the tap root may also function as a reservoir for food and water.

The tap root can grow very wide, and remain relatively protected underground, allowing the plant to save up energy for times when it may need it, such as when producing seeds. Many plants that use their tap root as a source of food actually create tap roots that humans find appealing as well, and the so-called root vegetables are generally plants with a tap root system. Carrots, turnips, radishes, parsnips, jicama and burdock are all examples of commonly-eaten plants where the main part of the plant eaten is the tap root itself. Generally these foods are not only quite nourishing, but are also extremely wet, because of the excess water the plant has been storing in them. It’s not difficult to imagine any of the examples above as being essentially water storage units. In fact, some plants, like jicama, seem to be almost like forms of solid water, the water content is so high.


Both a tap root system and a fibrous root system start as the same sort of root, and change a bit into the plant’s development. The first root that a plant sends out is called a radicle. In a tap root system, the radicle continues to push downwards and grow out, while sending out occasional small branches. In some cases these branches will scarcely be visible at all, as anyone who’s seen a carrot or turnip fresh from the ground knows. In a fibrous root system, on the other hand, the radicle will eventually fall away, to be replaced by a web of smaller roots.

Because of the size and depth of tap roots, plants that have them can be particularly difficult to get out of the ground. Transplanting plants with a tap root is notoriously more difficult than plants with a fibrous root system, and in many cases is almost impossible. Fully eliminating plants with a tap root can be difficult as well, because pulling up the entire tap root may not be feasible. This is often seen with dandelions, which have a very long and hardy tap root. People quickly notice that when trying to pull dandelions up to remove them from a garden, they seem to grow back year after year. This is because a part of the tap root has remained in the ground, and a new plant eventually grows from it.
By,
M Anem
Melaka
Malaysia
(18 RAMADAN 2011)

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