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

Spring overturn - overturn, Spring overturn - Overturn In spring and e...

Spring overturn - Overturn In spring and early summer season the increased solar radiation melts the ice cover, which, as it attains a temperature of 4° Celsius, becomes dense

Class Pisces, need different types of information about fishes and their pi...

need different types of information about fishes and their pictures

Signs of constrictive pericarditis, Q. Signs of constrictive pericarditis? ...

Q. Signs of constrictive pericarditis? 1) Jugular venous pressure (JVP) is elevated in all patients of CP which reflects the elevated diastolic pressure of the right atrium.

Determine the nutritional and functional role of bromine, Minerals : Bromin...

Minerals : Bromine                 Food Source       Brominated flour  Nutritional Functional role Not known to be essential to humans. Dough improver: KBrO 3 impr

Types of changes encountered during the support phase, What are the types o...

What are the types of changes encountered during the Support phase Adaptation - To accommodate changes to its environment Correction - To uncover defects in the Software

What is the host factors of implants, What is the Host Factors of implants ...

What is the Host Factors of implants These factors are very important and it is essential for the clinician to keep these in mind during the diagnosis and treatment planning st

What is muller manoeuver explain in details, What is Muller Manoeuver expla...

What is Muller Manoeuver explain in details? In this manoeuver, patient forcibly inspires while the nose is held closed and mouth firmly sealed for 10 seconds. It exaggerates t

What is coping, Q. What is Coping? Coping refers to a person's patterns...

Q. What is Coping? Coping refers to a person's patterns of response to stress. Coping is the process of managing circumstances, making effort to solve personal and interpersona

Gametogenesis - human development, Gametogenesis - Human Development G...

Gametogenesis - Human Development Gametogenesis as you are responsive is the process of formation and development of specialized reproductive cells, ova in females and sperms

Differentiate between the five kingdoms of organisms, Question 1: (a) G...

Question 1: (a) Give, in order, the major categories of taxonomic classification. (b) Differentiate between the five kingdoms of organisms. (c) Differentiate between net

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