Table of Contents
Definition:
Pollen involves the transfer of pollen grains from the anther to the skin or pistil of a plant. The pistil has four parts: the stigma, which is part of the ovary that contains the ovule, and the style, which is part of the stigma. Its main function is pollen transport, followed by fertilization.
A pollen tube is formed when the right pollen grains fall over the stalk and germinate, resulting in pollen grains becoming pollen. Both cross-pollination and self-pollination are possible. Self-pollination is recommended that most plants are bisexual or hermaphrodites.
Description of Pollen-Pistil interaction
Pollen-pistil interactions are defined as the sequence of events from the time the pollen is deposited to the filling until the pollen tube enters the egg. The first stage or first step in pollen-pistil contact is pollen transfer, which involves the transfer of pollen grains from one tree to the actions of the same flower or from flowering to another.
Pollen-pistil interaction occurs through the following steps:
- The first occurrence of pollen-pistil contact involves the crossing of real pollen into the right place.
- Pollen germination involves the formation of pollen tubes, which allow pollen grains to extract their contents.
- The pollen tube grows into an ovary in the style of a pistil.
- Male gametes enter the ovule and follow the synergid.
Pistil Structure
The pistil, placed in the center of the flower, is the female reproductive part of the flower. The main components are the basis of inflammation, the ovary (with sperm or ovules expected), the ovary stem or style, the pollen acceptance tip, and the color, which is shaped differently and adheres more frequently. The number of flower pistils varies depending on the type of flower. Each pistil is made up of one to many leaf-like structures, and its main role is to protect the ovules.
Pistil functions
The main purpose of the pistil is to form an egg. The following are some of the various pistil roles:
- In flowers, the pistil acts as the female reproductive organ of a flower.
- It helps to pollinate and fertilize.
- The pistil is also involved in the process of pollination.
- It is also useful for transporting pollen grains during pollination.
- Stigma, which has a sticky subject and plays an important role in the germination of pollen grains, is made of pistil.
Various Properties of Pollen
Self-pollination is common and very common in hermaphrodite flowers, but self-pollination sequences have a negative effect and lead to inbreeding stress. This leads to homozygous genes. As a result, plants have sprouted to promote pollen diversity. Outbreeding is the name of this.
Cross-pollination is encouraged by the following:
- Unisexual flower: Cross-pollination is the only option if the flower is not sexual, which means it is monogamous, either female or male.
- Non-Synchronization: The effectiveness of pollen depends on the time. Pollen release and acceptance of discrimination must take place simultaneously. Pollen grows and emerges before the stigma opens up, leading to loss of pollen or vice versa. Even though flowering is hermaphrodite, this prevents pollen.
- Self-stability and structural barriers are examples of inconsistencies within a flower (or plant). Sterilization indicates that even with pollen present, fertilization is not possible due to the failure of pollen growth. Structural barriers difference in height between gynoecium and androecium and other factors that prevent discrimination in pollination. These are genetic processes in a sense.
Pollen-pistil interaction separation
The pollen-pistil interaction involves various steps ranging from the time of pollen depositing on the flower cover to the time of the entry of the pollen tube into the ovule. Therefore, the related divisions surround the interaction phase.
With this process, it is easy with a pistil to find the right pollen suitable for one type or variety. The pistil determines whether pollen is compact or not. Subsequently, pollens receive levels of certain chemicals, such as sucrose, inositol, and boron, for use in contact.
In the case of inconsistencies during pollen-pistil interactions, these stages are common.
- Interspecific Inconsistency – Here, the pollen of one species could not germinate in another species after settling on pollination. For example, in the special pollen extraction of Brassica rapa stigmas containing the seeds of Brassica oleracea pollen, pollen tubes cannot penetrate into the mucous membranes.
- Intraspecific incompatibility – This type of incompatibility refers to the inability of pollen to germinate after falling on the skin of another plant of the same species. Example Solanum aethiopicum shows intraspecific incompatibility
- Incompatibility of self – Another type of intolerance occurs when single plant pollen does not respond to its discrimination and is unable to germinate. Example Potatoes show incompatibility due to another deficiency and pollen production.
Pollen can penetrate and drain water (absorb water based on the container) and monitor the pollen tube. The tube follows the carpal structure and grows toward the micropyle. The male gamete can travel to the egg cell.
Here, another distinction to note is, in relation to the pollen-pistil reaction, the passage of pollen into the embryo sac.
- Porogamy – Pollen tube travels through the micropyle of the plant. Another example is the lily.
- Monogamy – Here, the pollen tube pierces the plant tissue. Take the Cucurbita plant.
- Chalazagamy – Pollen tube reaches the fetal sac through chalaza. The Casuarina plant is an example.
Pollen-Pistil Interaction Steps
Pollen does not always include fertilizer. The pistil must produce pollen of the same type for pollen to occur. Finding pollen and pistils to share is not an easy task. For this, you need to know how pollen and pistil interactions occur to ensure effective fertilization. Listed below are the sections where pollen and pistils meet;
- Pollen grains are extracted from the male plant.
- The pistil of the female plant receives pollen grains.
- Pollen is acceptable when it is in contact with the pistil, but the ovary rejects the incompatible pollen.
- When a female plant receives pollen, it produces pollen tubes and releases its contents and chemicals.
- The style directs the pollen tubes towards the uterus.
- At this point, the male gamete meets the female gamete in the ovary.
- This is the whole process of pollen-pistil separation that is necessary for fertilization to take place successfully.
Also read: Important Topic Of Biology: Fertilization
FAQs
What is the pollen-pistil interaction? How is it mediated?
Pollen pistil interaction is an effective process that begins with pollen identification and ends with pollen stimulation or inhibition. The chemical components produced by pollen and pistil facilitate this interaction.
What is the breeding equipment?
Plant breeding equipment is a feature of plants or methods that prevent pollination itself and promote pollen diversity.
Name the breeding utensils used by plants to prevent pollination.
Plants use dicliny, dichogamy, pollen prepotency, incompatibility, herkogamy, and heterostyly to prevent pollen.
