The inner wall of the pollen grain is called the intine. Most, if not all, of the components of the exine derive from the sporophytic part of the anther (i.e., from the tapetum, a cell layer lining the anther) and are deposited on the pollen surface, while most components of the ...
Pollen analysis is the principal method used for providing quantitative estimates of the former occurrence of tree species (Seppä, 2007). It has the distinct advantage in that the data source (i.e. pollen) is spread in enormous quantitates into the air, and is deposited in various sedimenta...
Vareschiâs suggestions as to the modes of origin of a certain type of ogive banding and of parallel banding (Pflugfurcheneis) are dealt with in the light of his findings. It is pointed out that what appears to be a valuable new approach to the solution of glacier flow problems...
Plant-animal interactions may be affected by factors beyond the scale of the restoration. For example, surrounding landscape context may influence pollinator abundance and consequently the amount of pollen deposited. Decreased pollen receipt might then limit seed set. We hypothesized that in restorations...
Once it's deposited at its destination, grains of pollen settle on a flower's stigma -- the entrance to the ovary. Like with the gymnosperms, germination and pollen-tube formation follow fertilization, but this time both sperm are used. While one fertilizes the egg cell, the other is ...
Thus it is far-fetched to conclude that what is recorded in a single study conducted in a single stand is the gene flow rate characteristic of a species. The number of publications comparing gene flow patterns between different conditions is increasing. However, to date the comparison of ...
Obviously, the fewer allergenic trees in an individual's immediate vicinity, the less the chance of exposure. Good news is that the great majority of wind-borne pollen grains of all species are deposited quite close to their source. The closer to the tree the pollen stays, the less potential...
There are some indications that what is termed passive gathering can be augmented by electrostatic attraction between pollen grains and animals' bodies. Plants are inherently slightly negatively charged in warm. still air, the magnitude of the charge field depending on the plant's composition and arc...
This protandrous system of flower development is likely to favour cross- fertilisation in this species. Multiple inflorescences sometimes occur on the same individual, providing a potential mechanism for self- fertilisation, however, in these cases inflorescences have been asyn- chronous such that ...
Expressed on a field-area basis, IE includes all of the pollen grains released by tassels, including those that are not deposited on silks; thus, IE is a very small number on the order of 0.0004 (i.e., approximately 1 in 2500, cf. Section 2.1). View article Mangrove Ecology – Applic...