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

Agarose gel electrophoresis, Agarose gel electrophoresis  is the method to ...

Agarose gel electrophoresis  is the method to analyze the size of the DNA (or RNA) fragments. In the presence of an electric field, bigger fragments of DNA move through a gel slowe

What are the physiological systems, What are the physiological systems know...

What are the physiological systems known as integrative systems? Why is this designation justified? The integrative systems are the nervous system and the endocrine system. The

What are the major gas exchange organs of the plants, What are the major ga...

What are the major gas exchange organs of the plants? How is the procedure accomplished? In covering of the leaves and of the primary structure of the stem gas exchange is made

Define hexose monophosphate pathway, Define hexose monophosphate pathway ...

Define hexose monophosphate pathway The hexose monophosphate pathway (HMP also called the pentose phosphate pathway, or phoshogluconate pathway) consists of Mo irreversible o

Excretion, State the excretory organelles of various organisms

State the excretory organelles of various organisms

Why is ph regulation important for living beings, Why is pH regulation impo...

Why is pH regulation important for living beings? How do mineral salts participate in this regulation? The potential of hydrogen (pH) is a measure of the amount of hydrogen ion

Water absorption, Water Absorption Water status of a plant is determin...

Water Absorption Water status of a plant is determined by two major factors: i) water absorption and ii) water loss. We deal with water absorption in this section and water lo

Define the prevention of iron deficiency anaemia, Define the Prevention of ...

Define the Prevention of iron deficiency anaemia? As in the case of vitamin A deficiency, correction and prevention of dietary inadequacy of iron are important sustainable meth

How is the structure of a mitochondrion well adapted, How is the structure ...

How is the structure of a mitochondrion well adapted for the activities it carries out? The mitochondrial membranes segregate the enzymes and reactants of the Krebs cycle, faci

Explain rodent control and pests, Q. Explain Rodent Control and pests? ...

Q. Explain Rodent Control and pests? In any food establishment, varieties of insects, pests and rodents pose a big threat to the maintenance of hygienic surroundings. They

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