Gametophytic incompatibility, Biology

Assignment Help:

Gametophytic Incompatibility

In GSI systems callose deposition is not evident on the stigma but is very conspicuous in the pollen tube. Sometimes the callose deposition occurs even in the germpore, inhibiting pollen germination. In the Poaceae, the rejection reaction is completed within a few minutes after pollination and subsequent rejection or acceptance takes 10 minutes with the exception of Poaceae and Oenothera, the recognition/rejection reaction in GSI system occurs after the pollen tube has grown about two third the length of the style.

Genetically the recognition factor on the male side has been attributed to the male gametophyte; the proteins incorporated during pollen wall development in the intine are involved. Since in GSI systems the rejection reaction is comparatively delayed, is also possible that the synthesis or activation, and release of the recognition substances are also delayed and they occur in the pollen tube. In some species the tubes show reduced level of carbohydrates and starch.


Related Discussions:- Gametophytic incompatibility

Remove the crown for reuse-endodontics principles, Remove the crown for reu...

Remove the crown for reuse - If the decision is made to remove the crown for reuse - The visibility is increased - Allowing for much easier removal of canal obstructions -

Erysipelas, E r y s i p e l a s A sudden onset of infection wi...

E r y s i p e l a s A sudden onset of infection with the bacterium E rysipelothrix insidiosa ( E . rhusiopathiae ) is seen in turkeys and increasingly in free-rang

Glycolysis, Glycolysis Oxidation of glucose is called as glycolysis.Glu...

Glycolysis Oxidation of glucose is called as glycolysis.Glucose is oxidized to either lactate or pyruvate. Under aerobic conditions and the dominant product within most tissues

State the types of brain trauma, State the types of brain trauma? There...

State the types of brain trauma? There are two main types of brain trauma a) open head injury and b) closed head injury

What do you mean by transition period, Q. What do you mean by Transition Pe...

Q. What do you mean by Transition Period? The transition period from the Renaissance to the Modern period produced many notable workers and much literature. Botanists gradually

Explain techniques for broken instrument removal, Explain Techniques for Br...

Explain Techniques for Broken Instrument Removal Described by Gary Carr Staging platform (cutting in flat surface) a) Create straight line access to separated file using mod

Transcription in eukaryotes, The Eukaryotic transcription is more difficult...

The Eukaryotic transcription is more difficult than prokaryotic transcription. For example, in eukaryotes the genetic material DNA and therefore transcription is basically localize

Silver point and silver point removal-endodontics principles, Silver point:...

Silver point: -    Uses of silver point: ease of handing and placement, ductility, radiopacity,and have  some antibacterial activity. -    Lack of acceptable 3D seal of the ca

What is the use of vitamin a dry powder, Vitamin A dry powder Vitamin A...

Vitamin A dry powder Vitamin A dry powder is used in the (manufacture of dry mixtures) for which the oily ester concentrates are unsuitable or undesirable. Mainly, they are inc

Post-operative nursing care of cleft palate, Post-operative Nursing Care of...

Post-operative Nursing Care of Cleft Palate  Objective of Care  Provide adequate nutrition  Maintain oral hygiene  Apply restraints  Promote speech  Give

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