Cytokinins - apical dominance, Biology

Assignment Help:

Cytokinins - Apical Dominance

Cytokinins are also involved in the regulation of apical dominance. Wickson and Thimann studied the interaction of cytokinins and auxins in controlling the apical dominance. They isolated and cultured pea the stem sections in nutrient media containing auxins and no auxins. In the absence of auxins growth of lateral buds was not prevented. However, if cytokinins were added along with auxins, the inhibition of lateral buds was released. Wickson and Thimann also demonstrated the effect of cytokinins on entire shoots. When the intact shoot was soaked in a solution of kinetin, growth of lateral buds occurred even in the presence of shoot apical buds.

From this observation it was inferred that apical dominance exhibited by the shoot apex was overcome by the application of cytokinins. The present concept is that apical dominance is controlled by a balance between cytokinin and auxin concentrations. Some investigators suggest the possible inhibitory influence of cytokinins on auxin production. The cytokinin application to the lateral buds may inhibit the synthesis of certain forms of IAA oxidase, normally induced by IAA translocated from the terminal bud. With the repression of IAA oxidase, the spared auxin may stimulate lateral bud growth and shoot development. In addition to the possible inhibition of IAA degradation, cytokinins may initiate a sink effect at the site of lateral buds to attract diversion of nutrients from other regions.


Related Discussions:- Cytokinins - apical dominance

Bacterial diseases-pigs, Pigs This is a sub-acute or chronic infection ...

Pigs This is a sub-acute or chronic infection manifested by abortion, sterility, high piglet mortality and orchitis in pigs. Br. suis causes brucellosis among pigs. It is morph

Do fats with one or more ''kinky'' tail fatty acids, Do fats with one or mo...

Do fats with one or more 'kinky' tail fatty acids tend to be solid or liquid at room temperature? These are found in triglycerides forming what? Solid fats or oils? Is it opposite

Does the entire human genome into nucleosomes, How many of each type of cor...

How many of each type of core histone would it take to wrap the entire human genome into nucleosomes? How has evolution solved the problem of producing such a large number of prote

Define term food colours, Normal 0 false false false EN...

Normal 0 false false false EN-US X-NONE X-NONE MicrosoftInternetExplorer4

Wind energy and its advantages and disadvantages, Wind energy         ...

Wind energy            Wind power is one of most cheapest renewable energy sources today. Wind turbines convert the power of wind into electrical energy. Wind occurs due to t

How do taenias classify according to the division of sexes, How do taenias ...

How do taenias classify according to the division of sexes? Taenias are monoecious (hermaphrodite), the similar individual has female and male reproductive organs and undergoes

Nutrition, difference between holophytic nutrition and holozoic nutrition.

difference between holophytic nutrition and holozoic nutrition.

Determine some food sources for copper, Determine some Food Sources for Cop...

Determine some Food Sources for Copper? Foods containing more than 1 mg copper per 1000 kilocalories are considered high in copper and include green leafy vegetables, nuts, leg

What is the molecular formula of the compound, A solid compound was found t...

A solid compound was found to contain 42.11% C, 51.46%O and 6.43% H by weight. The molecular weight of the compound was 341. What is the molecular formula of the compound?

What is temporal lobe, Mention where the following are located in the human...

Mention where the following are located in the human brain, and give single function of each: a) Temporal lobe b) Cerebellum c) Corpus callosum

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