How Does a Plant Reproduce If it Does Not Have Seeds?
Concentrating on seed production requires a lot of energy from the plant itself — this process does not work for all plants and may actually negatively impact their numbers in some regions. As a solution, plants look to alternative reproduction, such as asexual means, including forming rapidly spreading growths or prolific spores across leaf undersides.
Rhizomes are underground stems that grow laterally from an originating plant, such as an iris. As the stem grows outward within the soil, it produces a new, above-ground shoot for foliage and photosynthesis processes. As the plant gains more energy from the sun and surrounding soil, the rhizome stems continue to spread to quickly populate an area. However, rhizomes cannot grow vigorously in compacted soil coupled with poor fertility. If you maintain your garden’s soil as a friable and nutrient-rich environment, the rhizomes retain their strength and vigor. Much like rhizomes, tubers form underground growths and eventual stems for reproductive success. Potatoes, being one of the most commonly known tubers, use the energy reserves in their bodies to cultivate new growths when planted in soil. Bulbs and corms store most of their energy in their bodies, rather than relying solely on the surrounding environment. When planted underground, they sprout and blossom depending on their stored nutrient reserves and available water.
Although seed dispersal produces more genetic diversity for a particular plant species, forming cloned runners above ground allows the plant to avoid energy depletion from seed production while gaining more nutrients from the surrounding soil. For example, runners develop from a strawberry plant’s crown. As the runner branches laterally, it slowly descends to the soil. As a result, it grows a new root and foliage system, referred to as a daughter plant. Retaining the same genetic information as the mother plant, these clones continue to multiply if conditions are optimal, such as access to ample sunlight and moisture. You can even remove the daughter plants from the mother plant to propagate your garden further in another location. In contrast, stolons grow much like runners, but have leaves for photosynthesis — they can produce their own energy reserves, unlike runners that cannot exist without attachment to the mother plant.
Some plants, such as cacti, grow new plants from cuttings. For example, fleshy leaves that break or fall off of a mother plant slowly root themselves in the soil. If conditions are optimal, this cutting eventually grows into a new plant. Cuttings help specific plants proliferate in unusual ways where seed production is not possible.
Plants that do not produce flowers, such as ferns, typically use spores as their main reproductive strategy. Spore-producing plants are often found in shady locations where seed production cannot occur since sunlight is scarce. Because spores appear on the plant leaves’ undersides, they must be lightweight so that the plant can produce as many as possible. As the leaves move in the breeze, spores detach and float away to another location. Unlike a seed, the spore must find nourishment from a host in the new location before it can grow into a new plant.
- University of Illinois Extension: Nonflowering Plants
- Biology-resources.com: Plants: Introduction to Vegetative Reproduction
- Southwest Educational Development Laboratory: Plants and Seeds
Writing professionally since 2010, Amy Rodriguez cultivates successful cacti, succulents, bulbs, carnivorous plants and orchids at home. With an electronics degree and more than 10 years of experience, she applies her love of gadgets to the gardening world as she continues her education through college classes and gardening activities.
How Does a Plant Reproduce If it Does Not Have Seeds?. Concentrating on seed production requires a lot of energy from the plant itself — this process does not work for all plants and may actually negatively impact their numbers in some regions. As a solution, plants look to alternative reproduction, such as asexual …
DK Science: Seed Plants
Most plants grow from seeds. These seed plants fall into two groups, angiosperms and gymnosperms. Angiosperms are the flowering plants. Their seeds develop inside a female reproductive part of the flower, called the ovary, which usually ripens into a protective FRUIT. Gymnosperms (conifers, Ginkgo, and cycads) do not have flowers or ovaries. Their seeds mature inside cones. Seeds may be carried away from the parent plant by wind, water, or animals.
Dandelion seeds have feathery parachutes to help them fly far from their parent plant. A dandelion flower is actually made up of many small flowers, called florets. Each develops a single fruit. The fruits form inside the closed-up seed head, after the yellow petals have withered away. When the weather is dry, the seed head opens, revealing a ball of parachutes. The slightest breeze lifts the parachutes into the air.
INSIDE A SEED
A seed is the first stage in the life cycle of a plant. Protected inside the tough seed coat, or testa, is the baby plant, called an embryo. Food, which fuels germination and growth, is either packed around the embryo or stored in special seed leaves, called cotyledons.
SPREADING WITHOUT SEEDS
Seeds are not the only means of reproduction. Some plants create offshoots of themselves – in the form of bulbs, tubers, corms, or rhizomes – that can grow into new plants. This type of reproduction is called vegetative reproduction. As only one parent plant is needed, the offspring is a clone of its parent.
A bulb is an underground bud with swollen leaf bases. Its food store allows flowers and leaves to grow quickly. New bulbs develop around the old one.
A tuber is a swollen stem or root with buds on its surface. When conditions are right, the tuber’s food store allows the buds to grow.
A corm is a swollen underground stem that provides energy for a growing bud. After the food in the old corm is used up, a new corm forms above it.
A rhizome is a horizontal stem that grows underground or on the surface. It divides and produces new buds and shoots along its branches.
GERMINATION OF A RUNNER BEAN
Most seeds require damp, warm conditions in order to sprout. During germination, the seed absorbs water and the embryo starts to use its food store. A young root, or radicle, begins to grow downward. Then a young shoot, or plumule, grows upward. This develops into the stem and produces leaves. The first leaves, called seed leaves or cotyledons, fuel the early growth until the plant’s true leaves appear.
A flower’s ovary usually develops into a fruit to protect the seeds and help disperse them. A fruit may be succulent (fleshy) or dry. Fruit is often tasty and colourful to attract fruit-eating animals. Its seeds can pass through an animal unharmed, falling to the ground in droppings. Seeds may also be dispersed on animals’ coats, by the wind, or by the fruit bursting open.
The seeds of dry fruits are dispersed in various ways. Peapods are dry fruits that split and shoot out their seeds by force. The hogweed fruit forms a papery wing around the seed, helping it to float on the breeze. The strawberry is a false fruit, but it is covered by tiny dry fruits, each with a seed.
Fleshy, brightly coloured, and often scented, succulent fruits are designed to attract the animals that eat and disperse them. Fleshy fruits such as apricots and cherries have a woody stone or pip that protects the seed. Called drupes, these fruits form from a single ovary. Many drupes, formed from many ovaries, may cluster to form a compound fruit, such as a raspberry.
Most plants grow from seeds. These seed plants fall into two groups, angiosperms and gymnosperms. Angiosperms are the flowering plants. Their seeds de