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

Culture negative endocarditis, In patients who have not received prior anti...

In patients who have not received prior antibiotics and who will ultimately have blood culture positive endocarditis, it is likely that 95 - 100 per cent of all cultures obtained w

Explain the main steps in the mongoose bioassay, Question : Explain the...

Question : Explain the main steps in the mongoose bioassay and the mouse bioassay as conducted for testing ciguatera in Mauritius? (i) Provide a brief description on the beh

Explain the numerical taxonomy, Explain the Numerical Taxonomy? Numeric...

Explain the Numerical Taxonomy? Numerical methods in taxonomy are not new. Simple statistical methods like standard deviations, t-tests and chi-squared have been used for sever

Genetically modified foods-golden rice, Normal 0 false false ...

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

Explain the secretary phase - menstrual cycle, Explain the Secretary Phase ...

Explain the Secretary Phase - Menstrual Cycle After ovulation, the lining of ovarian follicle is stimulated by LH to develop corpus luteum which produces progesterone. The endo

Explain denaturation and coagulation, Explain Denaturation and coagulation ...

Explain Denaturation and coagulation Denaturation and coagulation of the proteins are considered to be the chemical changes, since they involve the unfolding of proteins, whic

Protein necessity, Proteins necessity They are called as body builde...

Proteins necessity They are called as body builders. The proteins are used in various metabolic pathways and body building. They help in repairing the tissues of the b

Write in 5-6 lines about food pyramid, Write in 5-6 lines about food pyrami...

Write in 5-6 lines about food pyramid. The diabetes food pyramid divides food into six groups. These groups vary with each other on the basis of si-e occupied in the pyramid.

Define cerebral hemisphere tissue, Q. Define cerebral hemisphere tissue? ...

Q. Define cerebral hemisphere tissue? CEREBRAL WHITE MATTER - The remaining cerebral hemisphere tissue is the deeper cerebral white matter (60% of cerebral volume) which includ

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