Asexual reproduction means reproducing or creating offspring without the interaction of male and female plants. Only one "parent" organism is required to create offspring during asexual reproduction. Because only one parent plant is required, only one strand of genetic material is used to produce the offspring. This means that even though there are several different methods of asexual reproduction in plants, the offspring produced via each method are essentially clones of the parent plant.
Potato plants are a prime example of reproduction via tubers. Tuberous plants produce long branches which descend into the soil. Tubers form on the ends of these branches. Each tuber contains stored nutrients and water as well as genetic information. Tubers have buds present on the surface which grow upward to produce new plants identical to the parent.
Plants such as grasses, thistles and mare's tail use rhizomes to reproduce. Rhizomes tunnel beneath the surface of the soil, periodically producing new shoots. As each new offspring develops, it quickly produces its own rhizomes. If the original rhizome dies off or is severed, each offspring is able to sustain itself, with no detrimental effects from losing the original rhizome.
Some plants reproduce via a system of above-ground runners. One of the most obvious examples of this method is strawberry plants. The parent plant produces long runners from its base called stolons. These stolons grow and spread rapidly. The stolons produce numerous tiny root and shoot systems along their length. The immature roots begin to develop on contact with the earth and anchor themselves in as the shoots begin to grow into replicas of the parent plant.
Because asexual reproduction does not rely on male fertilization, the chances of reproducing increase. During periods of stress, such as drought or nutrient deficiency, plants which rely on sexual reproduction reproduce very little, if at all, whereas plants with asexual capabilities have a greater chance of reproducing even when conditions are poor, as only one parent is required. Asexual reproduction also allows a grower to select and retain the best varieties to suit her requirements. This is due to the fact that offspring of asexually reproducing plants are essentially duplicates of the parent, meaning that the desirable attributes of the original plants will remain present to the same degree in the offspring, with no chance of cross-breeding.
In the same way that desirable qualities will be present in offspring, undesirable characteristics will also be present, with no way of effectively removing them. If a genetic mutation occurs either in the parent plant or during reproduction, the mutation will be present in every new generation of offspring, which may result in little or no crop yield or increased susceptibility to disease. Offspring often develop very close to parent plants and to each other, resulting in increased competition for light, water and nutrients. This can lead to reduced yield or generally poor health and performance.