Plant Hormone in hindi |Class 11\NEET\AIIMS | Ncert theory |Complete Gibberlins Hormone|

Plant Hormone in hindi |  Class 11\NEET\AIIMS |          Complete Gibberlins Hormone| With Handwritten notes

Gibeerlins are important group of growth promoting hormones they stimulate growth largely in the shoot system of the plants and have little or no effect on Root where as auxin concentration have it's effect on both shoot and root. 

Discovery of gibberlins-

Japanese rice Farmers observe some abnormally tall and thin seedlings in their rice fields which never bored seeds, this disease was called foolish seedling disease. 

A scientist called Kurosawa found that the causative agent of the disease was gibberella fujikura of class Ascomycetes ,this fungus isolated the substance responsible for rapid growth from the extract of the fungus and it was named as gibberlic acid or GA3 .There are more than a hundred type of gibberellins reported from widely different organism GA1, GA2 and so on GA 3 was one of the first gibberlin to be discovered and remain the most intensively studied and common form of it.

STRUCTURE OF GIBBERLINS---

gibberellins are derived from for isoprenoid units forming a system of four rings classified into 19 carbon and 20 carbon gibberlins based on the presence of either 19 or 20 carbons there are other variations in the basic structure is especially the oxidation state of carbon 20 and the number and position of hydroxyl group in a molecule.

Synthesis and distribution of gibberellin--

Acetyl coenzyme a is the precursor of gibberellin. They are most abundant in young expanding organs being synthesized particularly in young apical leaves possibly In chloroplast Buds, seeds and root tips.

They migrate after synthesis in the nonpolar Manner that is up or down the plant from the leaves they move through phloem and xylem to fulfill the plant need they are transported through the vascular system.

ROLE OF GIBBERLINS-

• gibberlins stimulate stem growth in a dwarf and rosette plants beside a general increase in stem length gibberlins. besides General increase in the stem length of a plant GAs induced internodal growth in some genetically dwarf plants.

• In Rosette forming Florence plants example cabbage, radish internode growth is poor but large leaves appear to appear to arise in tufts, the internodes suddenly elongates and becomes normal before flowering.

• gibberellins can effectively break the dormancy off potato tubers and seeds of many trees ,gibberellins does acts antagonistically to abscisic acid ,it helps in promoting germination of seeds this by breaking the dormancy.

• gibberlins have been found to be effective in inducing parthenocarpy in tomato, Apple pear extra.

• biennial plants flower only when they receive room temperature during winter season if they do not receive suitable low temperature they can be made to flower with the help of gibberlins treatment in this way gibberlins can substitute vernalization demands.

• GA7 delay senescence so that fruit can be left on the tree for longer period, ripening of citrus fruits can be prevented with the help of gibberlins thus it is useful in storing the fruits.

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COMPLETE AUXIN HORMONE    (EASY EXPLAINED)

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Plant Hormone in hindi |Class 11\NEET\AIIMS | Ncert theory |Complete Auxin Hormone|

(EASY EXPLAINED.....SCORE FULL MARKS)

In this video I tried to complete the topic auxin of plant hormone in detail and tried to explain each and every concept regarding the phytohormone auxin. Just not included the contribution of scientist as it was not important but, i will soon upload a video exclusively for the contribution of scientist. Video of remaining hormones nd all PYQ (previous year question) will be uploaded soon... guys yrr like,share,subscribe krnaa ......motivation milta h suggestions are most invited ....new videos coming soon