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

............., notochotr is absent in the group ...........

notochotr is absent in the group ...........

Define the elements that affects the fitness, Define the elements that affe...

Define the elements that affects the Fitness? Fitness varies from a person to person. It is influenced by age, sex, heredity, personal habits, exercise and eating practices. Th

Pedigree charts, How do I complete a pedigree chart for genetics?

How do I complete a pedigree chart for genetics?

Severity of heat treatment for pasteurization depends on, Define on which s...

Define on which severity of heat treatment for pasteurization depends? The severity of heat treatment for pasteurization depends on: 1.  Heat resistance of target microorgan

Find aquaporin channels in the membranes, The secretary coil fills the lume...

The secretary coil fills the lumen with a NaCl solution that is isotonic with the blood plasma. As this solution moves upward through the reabsorptive duct, NaCl is reabsorbed into

Explain magnitude and direction of the electrostatic force, Three charges a...

Three charges are arranged as shown in the figure below. Find the magnitude and direction of the electrostatic force on the charge q = 4.78 nC at the origin. (Let r12 = 0.260 m.)

Which part of the teeth is it important to remove plaque, From which part o...

From which part of the teeth is it particularly important to remove plaque. It is most significant to remove plaque from among the teeth and from the region where the gum cover

Role of enzymes in metabolism, ROLE OF ENZYMES IN METABOLISM Enzymes re...

ROLE OF ENZYMES IN METABOLISM Enzymes require a non-protein  part  for  their optimal activity, which may be  a coenzyme or a metal ion. This has also been  stated earlier that

How are metarterioles different from arterioles, How are metarterioles diff...

How are metarterioles different from arterioles? Explain how fenestrated capillaries are different than continuous capillaries in terms of their structure and function.

Ciliary and flagellar movements, Normal 0 false false false...

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

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