Cleistogamy

Cleistogamy is a phenomenon in which plants pollinate themselves. The term cleistogamy refers to a marriage that is not open to the public. Cleistogamy-showing flowers are known as cleistogamous flowers. Peas, peanuts, and pansy are all members of the grass family. Viola, on the other hand, demonstrates both cleistogamy and chasmogamy.

Cleistogamy

Cleistogamy is a sort of automatic self-pollination in which certain plants reproduce by means of non-opening, self-pollinating flowers. This habit is most common in the grass family, and is most well known in peanuts, peas, and pansies. The cleistogamous plant genus Viola, on the other hand, is the largest.

Chasmogamy, or “open marriage,” is the more prevalent reverse of cleistogamy, or “closed marriage.” Cleistogamous flowers are produced by almost all plants that also produce chasmogamous flowers.  The fundamental advantage of cleistogamy over chasmogamy is that it requires fewer plant resources to produce seeds because it does not require the usage of pollen the production of petals, nectar, or vast amounts of pollenCleistogamy is highly beneficial for seed production in unfavorable situations due to its efficiency. After being badly injured by grazing, Impatiens capensis has been reported to produce only cleistogamous blooms and to establish populations on adverse sites with only cleistogamous flowers. Cleistogamy has the obvious disadvantage of causing self-fertilization, which may prevent the development of genetically superior plants.

Researchers are seeking to use cleistogamy to limit gene flow in genetically modified (GM) rapeseed in order to reduce mixing of GM and non-GM crops. However, preliminary findings from Co-Extra, a current EU research project, reveal that while cleistogamy reduces gene flow, it is not yet a consistently dependable technique for biocontainment; due to the cleistogamous trait’s instability, certain blooms may open and distribute genetically modified pollen.

The pollination of cleistogamous flowers is referred to as cleistogamy. Cleistogamous blooms do not open at all, indicating autogamy or self-fertilisation. Pollination is not dependent on pollinating agents.

Self-pollination is a kind of self-pollination in which pollination takes place within the same flower. Cleistogamous flowers are autogamous alone. Autogamy necessitates the presence of certain characteristics:

• Pollen release and stigma receptivity are synchronised
• The stigma and the anthers are in close proximity
• In flowers with exposed male and female reproductive organs, complete autogamy is impossible

Because pollination is not dependent on any external agent, cleistogamous blooms provide a guaranteed seed set. Peas, peanuts, and other plants that demonstrate cleistogamy are examples. Commelina, Viola, Oxalis, and other plants produce both chasmogamous and cleistogamous flowers.

The terms cleistogamy and chasmogamy refer to “closed marriage” and “open marriage,” respectively. Chasmogamous flowers open and display their reproductive parts to facilitate cross-pollination, but cleistogamous flowers do not.

Chasmogamous flowers are those that have their anthers and stigma visible. Pollinators such as wind, bees, insects, and other insects cross-pollinate most chasmogamous blooms. Both autogamy and allogamy can be seen in chasmogamous flowers. Cross-pollination is important in chasmogamous flowers because it increases genetic variation.

Features of Cleistogamous Flowers

• The flowers have finished blooming
• The petals aren’t particularly showy
• The flower’s reproductive organs are still contained

Advantages of Cleistogamy

There are certain drawbacks to self-fertilisation as well. It lowers genetic diversity and causes sadness due to inbreeding.

Cleistogamous flowers are produced by the majority of plants that also produce chasmogamous flowers. Both self-fertilisation and cross-fertilization are possible since both types of blooms are present. It reduces reliance on pollinators and environmental factors, resulting in increased reproductive success and genetic diversity.

• They don’t have to expend any energy or resources in order to produce magnificent flowers
• They do not rely on pollinators to pollinate them
• In difficult and unfavourable settings, they can develop seeds

Pollination is divided into two types: self-pollination and cross-pollination. Self-pollination happens within the same flower (autogamy) or between two blossoms of the same plant (geitonogamy). Cross-pollination, on the other hand, happens between blossoms on two separate plants. Plants that cross-pollinate require the assistance of a third party.

Male and female reproductive organs can be found in some flowers. Because the flowers close themselves in such a way that pollen grains are transmitted from the anther to the stigma of the same flower, cleistogamy is a state in which only self-pollination occurs. The viola is an example of a cleistogamous flower. One of the advantages of cleistogamy is that pollen grains are not transported by pollinators.

However, because these flowers self-pollinate over time, their offspring have limited genetic variety. Self-pollination also raises the chances of inheriting the parent plant’s faulty DNA. In mangroves, vivipary is a kind of seed germination. Because the environmental conditions are not ideal, the seed germinates inside the fruit while it is still attached to the parent plant.

Aside from the above-mentioned benefit, cleistogamy provides a few more perks. Cleistogamous flowers don’t have to waste resources to attract pollinators, and they don’t need to create smell or nectar to do so. In addition, they produce less pollen grains. Chasmogamous flowers are the polar opposite of these blooms. These flowers’ reproductive organs are not covered or enclosed, and pollinators are required to pollinate them.

Disadvantage of Cleistogamy

• Cleistogamy’s main clear disadvantage is that it cannot produce genetically varied seeds due to self-pollination

Significance of Cleistogamous

• Cleistogamous flowers are those that do not open at all
• The anthers and stigma are close together in such blooms
• When anthers dehisce in contact with the stigma, pollination takes place
•  Even in the absence of pollinators, cleistogamous blooms achieved a reliable seed set

Conclusion

Cleistogamy refers to the creation of closed flowers (CL), and autogamy results in the production of seeds. Flowers that open, on the other hand, are known as chasmogamous flowers (CH), and they have a variety of breeding methods depending on the taxon. Lord (1981) categorised cleistogamous species into four categories in a review of the subject. (1) Cuscuta obtusiflora (Rodriguez-Pontes, 2009), Griffith Ella hookeriana (Khosla et al., 2001), Hydrobryopsis sessilis (Sehgal et al., 2009), Macroptilium fraternum (Hoc et al., 2003), and Podostemum ceratophyllum (Hoc et al., 2003) are examples of prean (Philbrick, 1984). Pre Anthesis cleistogamy was seen in Icelandic populations of Campanula uniflora, but not in Greenlandic populations (Aegisdottir and Thorhallsdottir, 2006).