Dormant vegetative structures, Biology

Assignment Help:

Dormant Vegetative Structures

You have learnt that light a period of chilling or application of gibberellin often breaks seed dormancy and stimulates seed germination. Vegetative organs such as tubers, corms, bulb and winter buds can also enter a period of dormancy. What kind of stimulus is required for these dormant structures to resume growth? It is observed that light can stimulate bud break in certain trees and a period of chilling is necessary for triggering the development of dormant buds, and other organs in plants of temperate region. The period of chilling required for the bud break is usually a week or more.

Similarly, lengthening of days is necessary for breaking dormancy of winter buds exposed to light. Dormant buds can also be stimulated by the application of gibberellins. As you know gibberellins promote growth and Abscisic acid inhibits the growth. Accordingly, on breaking of bud dormancy increase in the level of GA and fall in the level of Abscisic acid has been noted. It needs to emphasised here that though all the buds of a plant receive the same dormancy breaking stimulus, however, it is only the apical bud that grows and the growth of other buds is inhibited by it because of apical dominance. Plants reproduce vegetatively through rhizomes, runners or stolons. Tuber formation in potatoes can be induced by exposing leaves to day length less than the critical value. Artificial application of hormones show that in tuber formation gibberellic acid decreases while Abscisic acid increases. The results show that the level of a particular hormone can increase growth in some organ and decrease in other.


Related Discussions:- Dormant vegetative structures

Define japanese criteria for functional foods, Define Japanese criteria for...

Define Japanese criteria for functional foods? The Japanese criteria for functional foods include: They are food (not capsules, pills/powder) on the basis of naturally o

Explain skeletal muscle, Explain Skeletal muscle Skeletal muscle has...

Explain Skeletal muscle Skeletal muscle has low activity of glucose-6-phosphate dehydogenase. Yet, like most other  tissues  it can synthesize ribose-5-phosphate.  This  is.

What factors lead to spoilage of fish flesh, What factors lead to spoilage ...

What factors lead to spoilage of fish flesh? A difference in the composition of tissues among different species, climate, procurement and holding practices are amongst few of

Definition of breach of contract, Question 1: Mention the types of IRBs...

Question 1: Mention the types of IRBs. If the IRB disapproves clinical study, can the sponsor approach another IRB? Justify your answer. Mention different types of IRBs

Explain the process of absorption of fats, Explain the process of Absorptio...

Explain the process of Absorption of Fats? After digestion, only 25% of triglycerides are broken completely to glycerol and fatty acids. Major digestion product is 2-monoacylgl

What are the vascular bundles, What are the vascular bundles? How does conf...

What are the vascular bundles? How does configuration of the vascular bundles within the stem differentiate monocots from dicots? The Vascular bundles are segments of xylem and

Explain about human digestive system, Which organs of the body are part of ...

Which organs of the body are part of the human digestive system? The digestive system, also called as "systema digestorium", or gastrointestinal system, is composed of the dige

Explain adverse effects of tenofovir disoproxil fumarate, Adverse effects o...

Adverse effects of Tenofovir disoproxil fumarate  The most common adverse effects have been nausea, vomiting and diarrhea. Renal failure, including a Fanconi-like syndrome, has

Factors influencing uptake from lumen to intestinal cells, Define Factors ...

Define Factors influencing  uptake from lumen to intestinal cells? inhibition by intrinsic matrix, inhibition by dietary fiber sources, differential crowding by

Polyphyletic theory, Please I need short notes on polyphylrtic theory

Please I need short notes on polyphylrtic theory

Write Your Message!

Captcha
Free Assignment Quote

Assured A++ Grade

Get guaranteed satisfaction & time on delivery in every assignment order you paid with us! We ensure premium quality solution document along with free turntin report!

All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd