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

#fbiodiversitytitle.., Alimitation of five kingdom classification sk questi...

Alimitation of five kingdom classification sk question #Minimum 100 words accepted#

Conservation, What term is used to describe the range of organisms in a hab...

What term is used to describe the range of organisms in a habitat

Initiation codon, Initiation Codon is the codon at which the translation o...

Initiation Codon is the codon at which the translation of a polypeptide chain is initiated. This is generally the first AUG triplet in the mRNA molecule from 5' end, where the rib

Biology, While studying evolution, a student comes across a cladogram that ...

While studying evolution, a student comes across a cladogram that includes clades like amphibia, reptilia, aves, and mammalia. What must be the basal clade?

Cockroach heart, How last chamber of heart in cockroach receives blood with...

How last chamber of heart in cockroach receives blood without having ostia?

Basics of echocardiography, Echocardiography is one of the -most frequent...

Echocardiography is one of the -most frequently used imaging modalities for diagnosing cardiovascular diseases. It i's versatile and is applicable in the entire spectrum of

Ionosinin ic pathway , how ionosinic pathway ric acid from ammonia forms ...

how ionosinic pathway ric acid from ammonia forms u

Why is boiling used as a control, Substance A is being investigated to see ...

Substance A is being investigated to see if it is an enzyme. When substance A is mixed with substance B a reaction takes place. A control experiment is conducted using a sample of

Explain thoracic, Thoracic (non-cardiac) Antibiotic prophylaxis is give...

Thoracic (non-cardiac) Antibiotic prophylaxis is given routinely in thoracic surgery, but sup- porting data are sparse. In one study, a single preoperative dose of cefazolin be

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