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

How the nurse reviews the labels of the medications, A post-operative clien...

A post-operative client has an order for Demerol 35 mg and Phenergan 12.5 mg. The nurse reviews the labels of the medications. Injectable Demerol (meperidine hydrochloride) is prep

How sugar is used in icings, How sugar is used in Icings? Sugars provid...

How sugar is used in Icings? Sugars provide sweetness, flavor, bulk and structure to icings and frostings. In addition to sweetness and flavor, icings also function as a barrie

Show endocrine glands involved in the menstrual cycle, Q. What are the endo...

Q. What are the endocrine glands involved in the menstrual cycle? What are the hormones in action? The endocrine glands that secrete hormones involved in the menstrual cycle ar

Explain trifluridine, Explain Trifluridine  (Viroptic)  Trifluridine is...

Explain Trifluridine  (Viroptic)  Trifluridine is a nucleoside analog active against herpes viruses, including acyclovir-resistant strains. Marketed in an ophthalmic preparatio

Explain working of dietitians and nutritionists, Dietitians and nutritionis...

Dietitians and nutritionists Dietitians and nutritionists, who are associated with hospitals and clinics generally have regular work hours. At times, they may be required to wo

What is centrioles in cell structure, What is Centrioles in cell structure?...

What is Centrioles in cell structure? Most cells of higher organisms contain pairs of cylindrical bodies called centrioles, which help to organize microtubules in cell division

Daily torpor, Normal 0 false false false EN-IN X-NONE...

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

Algae, classificationof algae

classificationof algae

Synergistic and sequential effects of hormones, Synergistic and Sequential ...

Synergistic and Sequential Effects of Hormones In vitro studies on callus and suspension cultures have brought out two interesting findings. The nature and direction of differ

Zoonotic diseases-yellow fever, Yellow fever Yellow fever also known a...

Yellow fever Yellow fever also known as Black Vomit and American plaque is a viral disease primarily of monkeys and transmitted to man by female Aedes mosquitoes. It is caused

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