Flowering plants rely on seeds for vegetative reproduction to ensure the continuation of generations. However, other plant species don’t produce flowers or any seeds. As a result, many seedless plants with primitive origins require highly specialized reproductive techniques to boost their numbers.
Many seedless plants reproduce sexually, while others reproduce asexually, and others mix both methods. In the basic form, the plants rely on spores, rhizomes, and plantlets for natural propagation without humans helping.
There is much more to know about their life cycle and sexual organs when looking at ferns, fungi, and nonflowering plants. In our guide, you can learn more about the types of seedless plants and where seedless plants grow from.
By the end, you’ll see how does the reproduction of seedless plants differ from that of seed plants. (Learn How Long Is Grass Seed Good For)
How Do Seedless Plants Reproduce For Kids?
Scientists believe that plants such as ferns, mosses, horsetails, and liverworts initially originated on Earth 400 million years ago.
Even though the plants have stems, roots, and leaves like other plants, they do not produce flowers since they are seedless plants.
These seedless plants have specialized tissues for conducting water and nutrients due to the lack of a system for storing and delivering water.
Reproduction of seedless plants
Now the question is, how do the seedless plants reproduce? The seedless plants reproduce via seed-like objects, known as spores, or they produce through asexual reproduction, unlike seed plants.
What exactly are spores?
Spores are usually single-celled or unicellular entities with only one set of chromosomes. Once the conditions are favorable, they divide their cells and grow into full-fledged plants.
Spores are produced in large quantities in a seedless plant and are carried by the wind to new regions where they can thrive because of their small size and light weight.
In seedless plants, what is asexual reproduction?
Asexual reproduction is possible in some seedless plants. When a piece of the plant falls and grows into a new plant on its own, this is how it reproduces.
What are vascular and non-vascular plants?
Plants with a series of tubes that can convey water are known as vascular plants. Plants that produce seeds are all vascular, whereas seedless plants can be either vascular or non-vascular.
Ferns and horsetails are examples of seedless vascular plants. Such plants’ roots, stems, and leaves are all in good shape.
Mosses, liverworts, and hornworts are examples of non-vascular plants. Because these plants lack well-differentiated roots, shoots, stems, and a water transport system, they can only flourish in damp environments. (Read Dill Seed Vs Dill Weed)
Types of Seedless Vascular Plants
Ferns are one of the most popular plants, and you’ve probably seen them in hotels and airports. Ferns produces spores on their leaf undersides, shown by tiny dark dots.
Having a vascular system makes horsetails and ferns near relatives of seed plants. Unfortunately, most of these plants are extinct, so it is one plant you’ll most likely not see.
Non-Vascular Seedless Plants Examples
Moss is little, spongy plants that grow barely a few inches high. They grow in bunches and produce a ground carpet. Mosses use rhizoids to attach to rocks and soil.
One of the earliest known plants to have colonize earth, worts are considered the simplest of all plants.
They are small, flat, and arranged like leaves on the ground. They have rhizoids instead of roots to absorb moisture.
They, like mosses, spend wet regions, and some species thrive entirely in water.
Facts On Moss
- In a hostile environment, where soil remains frozen, mosses store food and shelter for many species of small insects and food to reindeer.
- Mosses absorb pollutants from the air.
- Dried peat moss is a renewable resource.
- Coal is primarily made of seedless vascular plants.
How Do We Grow Seedless Plants?
Pteridophyta plants are seedless, and they do not produce seeds like Spermatophyta plants. However, Pteridophyta and Spermatophyta share the same life cycle pattern.
Plants in both divisions have generations that alternate where the main plant body shows sporophytic generation and the gametophytic generation is reduced.
The sporophyte meispores reproduce asexually. Therefore, the gametophytic generation is haploid once the meispores germinate.
They reproduce sexually using gametes. First, the zygote develops into an embryo, then a zygote sporophyte.
The female gametophyte is reduced and kept in the megasporangium (ovule), therefore keeping the plant embryo generated during sexual reproduction inside the ovul. As a result, the ovule matures to seed to produce gametophytes tracheophyte.
Heterspory is the most critical evolutionary phase before seed production.
Homosporous seedless plants (ferns) or some pteridophytes, including Sealginella, are heterosporous. These plants did not yield seeds but showed signs of seed development.
The vascular plants, or tracheophytes, make up most terrestrial plants and are the most visible and dominating. These organs contain vascular tissue that transports water and other substances all around the plant. (Read Cover Grass Seed With Straw Guide)
The term “seedless vascular plants” refers to plants with a vascular system but do not bear fruit.
When seeds are absent, haploid, unicellular spores are used to propagate seedless vascular plants, such as horsetails and ferns.
With fertilization, seedless vascular plants still require water, as the sperm must swim on a layer of moisture to reach the egg.
A key reason for the abundance of ferns and their cousins in moist areas is because of this step in reproduction.
During the seedless vascular plant’s life cycle, there occurs an alternation of plant evolution in which the diploid sporophyte alternates.
For a plant’s life cycle, the diploid sporophyte is the most prominent, while the gametophyte is a less noticeable but autonomous organism.
For most of the plant’s history, the dominating period of its life cycle has seen an apparent reversal of roles.
How Do Seed Plants Differ From Seedless Plants?
The distinction between seed plants and seedless plants is that seed plants produce seeds for multiplication, whereas seedless plants do not.
There are four major divisions of plants: Thallophyta, Bryophyta, Pteridophyta, and Spermatophyta.
Plants dividing Seed plants (Spermatophyta) have seeds, whereas seedless plants (all three divisions) do not.
Thallophytes are the most essential plants other than spermatophytes (seed-bearing plants).
Plants reproduce largely by seed. Seedless plants reproduce asexually through spores unlike many seeds on other plants giving life.
- A diploid sporophyte and a haploid gametophyte phase occur in seedless vascular plants.
- A diploid sporophyte and a haploid gametophyte phase alternates in seedless vascular plants.
- Seedless vascular plants reproduce using unicellular haploid spores, which are easily dispersed by wind.
- Seedless vascular plants need water for sperm motility; hence they thrive in damp settings.
- A gametophyte is an organism (or the haploid phase of its life cycle) that produces gametes during mitosis in order to produce a zygote.
- Sporophyte: (or the diploid phase of its life cycle) that generates lightweight spores during meiosis in order to create gametophytes is known as a mature sporophyte.
- Tracheophyte: Ferns, conifers, and flowering plants are examples of a plant possessing vascular tissue.
The most common land plant category is the tracheophytes (vascular plants). They carry tissue by containing water and other substances.
With over 260,000 species, tracheophytes make up over 90% of the earth’s vegetation. By the late Devonian, plants had evolved vascular tissue, leaves, and root systems.
Seedless vascular plants are those that have vascular tissue but no blooms or seeds.
Rather than seeds, seedless vascular plants like ferns and horsetails reproduce by haploid unicellular spores.
The sperm must swim on a layer of moisture to reach the egg, so seedless vascular plants are water dependent.
This reproductive process explains why ferns and their relatives flourish in wet environments like marshes and rainforests.
The diploid sporophyte phase alternates with the haploid gametophyte phase in seedless vascular plants.
The diploid sporophyte is the primary phase of the life cycle, while the gametophyte is a small yet independent organism.
Roles are obviously reversed in the dominant phase of the plant’s life cycle.
The life cycle of a fern shows alternation through a succession of generations with a dominant sporophyte stage. The sporophyte stage is dominant.
The plant’s vascular system, which transports water and other substances throughout the plant, comprises xylem and phloem.
Silica accumulates in epidermal cells, and cell division in ferns and horsetail plants contributes to the stiffness of their thick walls.
Rhizomes, or underground stems, anchor plants to the ground. Horsetails today are homosporous, producing bisexual gametophytes.
The Importance of Seedless Vascular Plants
Ferns help the environment by increasing rock weathering, accelerating topsoil development, and reducing erosion by spreading rhizomes into the soil.
The nitrogen-fixing cyanobacteria found in Azolla water ferns help to restore this crucial nutrient to aquatic ecosystems.
Seedless plants have historically aided human life by serving as tools, fuel, and medicine.
Sphagnum, or dried peat moss, is a renewable resource frequently utilized as a fuel in several parts of Europe. In addition, cranberry and blueberry bushes are planted in sphagnum bogs.
Sphagnum moss is a prominent soil conditioner due to its capacity to hold moisture. Florists use sphagnum blocks to keep floral arrangements moist.
Learning objectives evaluate how seedless vascular plants have evolved. The dominant and most conspicuous group of land plants is the vascular plants or tracheophytes.
They comprise tissue that will transport water and other substances across the plant.
Plants developed vascular tissue, well-defined leaves, and well-defined root systems by the late Devonian period. Plants increased in height and size as a result of these benefits, and they could spread to all ecosystems.
Plants with vascular tissue but no flowers or seeds are referred to as seedless vascular plants. In seedless vascular plants like ferns and horsetails, haploid, unicellular spores replace seeds in reproduction.
This step in the reproduction explains why ferns and their cousins thrive in moist environments like marshes and rainforests. Seedless vascular plants have a generational cycle in which the diploid sporophyte phase alternates with the haploid gametophyte phase.
The dominant phase of the life cycle is the diploid sporophyte, while the gametophyte is a small but self-sufficient creature. There has been a definite role reversal in the dominant stage of the life cycle throughout plant history.