Which of the growth substance acts as a stimulant during nodule formation in leguminous planta)Ethyleneb)ABAc)IAAd)MorphactinCorrect answer is option 'C'. Can you explain this answer?

Question

Answer

IAA is actually a type of Auxin hormone so it help in nodule formation.

Answer

Indole acetic acid is a phytohormone which plays a vital role in plant growth and development. The root nodules were found to contain more IAA and tryptophan than root; The IAA metabolizing enzymes IAA oxidase, IAA peroxidase  and polyphenol oxidase  were higher in root than nodule Most of the explored legumes are crop plants that are studied in relation to nitrogen fixation by the symbiont in root nodule. Besides nitrogen fixation, the root nodules of legume plants contained appreciable amount of IAA that are involved in genesis and development of nodules Rhizobial nodule bacteria produced IAA, which plays an important role in plant growth and in legume-rhizobia interaction.

Answer

Role of Auxin in Nodule Formation
Nodule formation in leguminous plants is a crucial process for nitrogen fixation, and the growth substance that plays a significant role in this is Indole-3-acetic acid (IAA), commonly known as auxin.
What is Auxin (IAA)?
- Auxin is a plant hormone that regulates various physiological processes, including cell elongation, apical dominance, and root development.
- It is primarily produced in the tips of shoots and roots.
Mechanism in Nodule Formation
- Stimulation of Cell Division: Auxin promotes cell division in the root cortex, which is essential for nodule formation.
- Root Hair Development: It enhances the growth of root hairs, increasing the surface area for Rhizobium bacteria to attach and initiate nodule formation.
- Signaling Pathway: Auxin acts as a signaling molecule, triggering the expression of genes necessary for nodule development.
Interaction with Rhizobium
- When leguminous plants are infected by Rhizobium, auxin levels increase, promoting the formation of nodules.
- The bacteria, in turn, can produce auxin, creating a feedback loop that enhances nodule formation and function.
Conclusion
In summary, auxin (IAA) is the key growth substance that acts as a stimulant during nodule formation in leguminous plants. Its ability to regulate cell division and enhance root hair development is vital for establishing a symbiotic relationship with nitrogen-fixing bacteria. Understanding this process is essential for improving agricultural practices related to legumes and enhancing soil fertility.

Answer

Yes!!!Indole acetic acid...

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