Salvinia

[Salvinia - Overview](#Salvinia - Overview)

[Reproduction and Growth](#Reproduction and Growth)

[Frequently Asked Questions](#Frequently Asked Questions)

Salvinia - Overview

The genus Salvinia belongs to the family Salviniaceae, and is commonly referred to as watermoss. It is related to other water ferns such as the mosquito fern, Azolla. Furthermore, Salvinia is heterosporous, meaning it synthesizes spores of varying sizes.

The stems of Salvinia are dichotomously branched rhizomes expanding horizontally. They are aerenchymatous in nature and protostelic. The leaves are dimorphic and simple, also aerenchymatous. At maturity, the leaves appear in whorls of three, with blades that are round to oblong. The eggbeater shaped hair departs into four branches uniting at the tips.

Abode of Salvinia spp.

Nutrient-rich Water Entities

The slow and steady movement of water bodies such as reservoirs, ponds, rice fields, and ponds

Resists mild temperatures and salinity

Salvinia is a genus of aquatic ferns in the family Salviniaceae. It is native to tropical and subtropical regions of the world, with most species occurring in Central and South America. The plants are free-floating, with leaves that are round to oval in shape and have a hairy surface. Salvinia can form dense mats on the surface of lakes and ponds, blocking sunlight and reducing oxygen levels, making it a serious pest in some areas.

The aquatic fern family Salviniaceae is placed in the order Hydripteridales, consisting of Salvinia, the single genus. Ten species of Salvinia are known to exist all around the world.

#The horizontal rhizome just under the surface of water gives rise to these free-floating ferns, with each plant being a ramet’s colony. The ramet is made up of a node, internode, floating leaves, associated buds, and submerged roots.

The leaf is an altered form of the root, posing the functions of a leaf. Therefore, there are no true leaves. These structures are divided into various filaments, with hair-like projections along the length. These projections are essential for absorbing water and providing nourishment to the plant.

Morphologically, Salvinia is variable, largely in response to the amount of crowding and availability of nutrients. These two factors are interdependent.

Explore Further: What are Vascular Plants?

Reproduction and Growth

Since Salvinia has 45 chromosomes, it is pentaploid and incapable of carrying out sexual reproduction. Each node supports an order of at least 3 axillary buds which grow successfully under favourable conditions and at least 6 responding to damage. Availability of nutrients is the deciding factor for the growth rate, number of axillary buds, and size of the plant. The growth is apically dominant and advances by the expansion of the axillary and apical buds, with the former producing branches. Formation of new plants occurs when older ones decay and break due to damage or senescence.

Growth Affecting Factors

Salvinia has a perennial plant life which is not affected by seasonal changes, even though variations in growth may occur due to seasonal alterations, such as temperature. It has adapted well to waters with a high nutritive value, and can absorb nutrients quickly when they are available. The development of axillary buds is associated with the nitrogen content of the plant, and the nitrogen content increases after the removal of buds by insects or other agents.

The availability of nitrogen affects the root and leaf size in Salvinia; when nitrogen is low, roots are longer and leaves are larger. Additionally, rhizome branching is decreased and sporocarps occur more frequently. The content of nitrogen in Salvinia is typically between 0.6-4% dry weight.

The favourable temperature for plant growth is close to 30 °C. Research has shown that no growth occurs above 40 °C and below 10 °C. Temperature does not affect the parts of the axillary buds which expand and give rise to new branches. Plants may be destroyed by frosts, but the unfrozen buds and protected parts may survive. Water bodies are typically chiller than the air in summers and warmer in winter due to thermal inertia, which helps protect Salvinia from extreme temperatures.

Initiation of growth of dormant buds allows Salvinia to compensate for the damage to buds. However, complete compensation only takes place with the availability of higher levels of nitrogen. Compensatory growth is not induced by the destruction of rhizomes and leaves.

Frequently Asked Questions

What are the Uses of Salvinia?

Most of them are invasive ornamental plants. These water weeds can form dense mats on water bodies. For example, Giant Salvinia is a typical water weed. Moreover, the hydrophobic trichomes of Salvinia (S.molesta) do not repel oil, making them excellent models for clearing oil spills.

What is Azolla?

Azolla is a genus of seven species of aquatic ferns in the family Salviniaceae. They are extremely small, floating plants that thrive in warm climates and are often used as a biofertilizer in rice paddies.

Azolla is a genus of water fern belonging to the family Salviniaceae. It is an invasive plant that can significantly alter the aquatic ecosystem, and is closely related to Salvinia.

Yes, Salvinia is a pteridophyte.

Yes, Salvinia is a pteridophyte that has vascular tissues. They belong to a clade called Tracheophytes or vascular plants. The vascular plants include ferns, gymnosperms, clubmosses, horsetails and angiosperms.

Back To Study Material

NEET NCERT Solutions (Biology)

Reach to us