Autogamy

In this post, we will study about the phenomenon known as autogamy in plants.

Autogamy, also known as self-fertilisation, is the fusion of two gametes that are derived from the same individual. Autogamy is most commonly observed in the form of self-pollination, which is a reproductive strategy used by a large number of flowering plant species. There have been reports of protist species adopting autogamy as a mode of reproduction, though this has not been confirmed. Flowering plants engage in autogamy on a regular basis, whereas protists that engage in autogamy only do so when they are exposed to stressful conditions.

Paramecium aurelia is the protozoan that has been examined the most for its ability to reproduce. Similar to other unicellular organisms, Paramecium aurelia reproduces asexually through binary fission or sexually through cross-fertilization, depending on the species. When exposed to nutritional stress, Paramecium aurelia will go through meiosis, which will result in the fusing of gametic-like nuclei. This has been demonstrated in laboratory trials. There are several stages to this process, which is referred to as “hemixis,” which is a chromosomal rearrangement process. For starters, the two micronucleus of Paramecium aurelia grow in size and divide twice, resulting in the formation of eight nuclei. The daughter nuclei of some of these daughter nuclei will continue to divide, resulting in the formation of potential future gametic nuclei. Two further divisions will take place in one of these possible gametic nuclei. In this step, two of the four daughter nuclei that are formed become anlagen, or cells that will become part of the new organism. The other two remain as daughter nuclei. The other two daughter nuclei develop into gametic micronuclei, which are capable of self-fertilisation by autogamous self-fertilisation. It is only when the Paramecium aurelia is subjected to dietary stress that these nuclear divisions may be recognised in the organism. According to the findings of the research, Paramecium aurelia undergo autogamy at the same time as other individuals of the same species.

Autogamy 

Autogamy is a type of “self-marriage” or “self-union” in which the gametes of a female gamete and a male gamete pollen grain are combined and fused to form a zygote that is produced by the same flower.

Autogamy is defined as follows: When Pollen Grain is moved from the anther to the stigma within the same flower, this is known as autogamy, which is a sort of self-pollination. It is possible for flowers to be encircled with petals or to be open; an encircled or closed flower is known as Cleistogamous, while an open flower is known as chasmogamous; the form of pollination is known as Cleistogamy or chasmogamy, respectively. Autogamous flower refers to a flower that has gone through the process of autogamy pollination.

When it comes to plants, the evolutionary transition from outcrossing to self-fertilisation is one of the most common transitions that they go through. Self-fertilising flowering plants account for around 10-15 percent of the total number of flowering plants. 

Autogamy is the most closely related type of inbreeding. Homozygosity is the result of autogamy. They develop homozygous balance and do not show substantial inbreeding depression, which is characteristic of such animals. 

Mechanism that stimulates self-pollination

  1. Being bisexual. Bisexuality is defined as the presence of both male and female reproductive organs in the same flower. The existence of bisexual flowers is a requirement for self-pollination to occur successfully. Hermaphrodite blooms can be found on all of the self-pollinated plants.
  2. Homogamy is a type of polygamy. Homogamy is the term used to describe the maturation of anthers and stigma of a flower at the same time. In most cases, homogamy is required for self-pollination to occur.
  3. Cleistogamy is a type of marriage in which both partners are married at the same time. Cleistogamy is the term used to describe the process by which pollination and fertilisation take place in an unopened flower bud. It ensures self-pollination and avoids cross-pollination in the flowering plant. Cleistogamy has been observed in some wheat, barley, oat, and other grass species, as well as in several other plant species.
  4. Chasmogamy is a type of polygamy. Chasmogamy is the term used to describe the opening of flowers only after pollination has been completed. This is also found in crops such as wheat, barley, rice, and oats, and it helps to encourage self-pollination.
  5. the position of the Anthers. For example, in some species, stigmas are encircled by anthers in such a way that self-pollination is virtually guaranteed. 

Examples of Autogamy

Tomatoes and brinjal are examples of vegetables in this condition. Self-pollination is ensured in some legumes because the stamens and stigma are encased by the petals in a manner that prevents pollination by other insects. Green gram, black gram, soybean, chickpea, and pea are just a few examples.

Autogamy occurs in blooming plants in the form of self-pollination, which is an example of autogamy. Self-pollination occurs when the sperm contained in the pollen from the stamen of a plant travels to the carpels of the same plant and fertilises the egg cell that is already present there. Self-pollination can be done totally autogamously or geitonogamously, depending on the species. It was the same flower that provided the egg and sperm cells that resulted in a successful union in the first case. Alternatively, the sperm and egg cells can come from distinct flowers on the same plant when using the latter method. While the latter method blurs the distinction between autogamous self-fertilization and regular sexual reproduction, it is nonetheless classified as autogamous self-fertilization under the laws of Canada.

Because of the expression of harmful recessive mutations, self-pollination can result in inbreeding depression in plants. Due to the lack of genetic variation produced by meiosis followed by self-pollination, it is unclear how meiosis in self-pollinating plants has been adaptively maintained over an extended period of time in preference to a more complicated and less costly asexual ameiotic process for producing progeny. The plant Arabidopsis thaliana, for example, is a largely self-pollinating species with an estimated outcrossing rate in the wild of less than 0.3 percent. Self-pollination appears to have evolved perhaps a million years ago or more. An adaptive feature of meiosis that may explain its long-term maintenance in self-pollinating plants is the ability to repair DNA damage with high efficiency through recombination.

Conclusion

Self-indulgence, sensuality, and voluptuousness are all used as synonyms. abstinence from food, a. self-sacrificing, altruistic, austere, abstinence from alcohol self-evident, a. axiomatic, unquestionably plain Introspection, often known as self-examination, is a type of introspection. clearly defined, a. self-explanatory autophobia, n. self-distrust, and n. self-fear 

As described by the International Union of Botanical Sciences, autogamy refers to a sort of self-pollination that is mostly found in flowering plants and in which the pollen grains of an anther of a flower are deposited on the stigma of a different plant. Within the same flower, autogamy might take place. Another way of putting it is that it is a self-fertilization process that is made possible by the fusion of two gametes that are both generated from the same flower.

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What exactly is autogamy?

Ans : Autogamy (also known as self-pollination): It is a type of pollination in which pollen from t...Read full

What is the opposite of autogamy?

Ans : Autogamy, often known as self-pollination, is the polar opposite of allogamy.