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

What is gastrulation, What is gastrulation? How during gastrulation are the...

What is gastrulation? How during gastrulation are the first two germ layers formed? What are these germ layers? Gastrulation is the process by which a portion of the blastula w

Describe the structure of chromatin and chromosomes, Describe how the struc...

Describe how the structure of chromatin and chromosomes facilitates the following functions: a) DNA packaging. b) Regulation of gene expression.  c) Replication at the

How all the exercises are active exercises, How All these exercises are act...

How All these exercises are active exercises All these exercises are active exercises that is active exercises are those type of physical activities carried out by the individ

Signify the glands which are located at upper end of kidney, Part of the en...

Part of the endocrine system in humans, these 2 glands are small bodies located at upper end of every kidney. While these glands perform a range of functions, two of the most signi

Explain the term - diffusion, Explain the term-Diffusion Diffusion occu...

Explain the term-Diffusion Diffusion occurs from the side of greater concentration to the side of lesser concentration. In aqueous humour this occurs from the plasma side in th

Calculate micronutrient and other nutrient requirements, Calculate Micronut...

Calculate Micronutrient and other specific nutrient requirements? The recommended average daily per capita intake of various specific nutrients for typical population requiring

Congenital aortic stenosis-types of aortic stenosis, Congenital Aortic Sten...

Congenital Aortic Stenosis :  The valve may be unicuspid, bicuspid or tricuspid. Rarely it is a dome shaped diaphragm. Uni commissural aortic stenosis produces significant sy

Ion channel-linked receptors, Ion channel-linked receptors will transmitter...

Ion channel-linked receptors will transmitter-gated ion channels or ionotrophic receptors that   are included in the rapid synaptic signaling among electrically excitable cells. No

Cleavage - development biology, Cleavage - Development Biology Cleavag...

Cleavage - Development Biology Cleavage or segmentation is a series of cell divisions of the fertilized .egg through which it is converted into a multicellular structure, call

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