134 Ruminations (0) absent, (1) testal, (2) tegminal and/or chalazal
The megaspore tetrads are arranged linearly, and the megaspore at the chalazal
end is functional.
Occurring at the chalazal
end of the ovule there is a cup-shaped region of thick-walled cells (see Figure 4G).
Detail of chalazal
and micropylar region of the ovule in longitudinal section.
Seed length was measured from hilar to chalazal
end; seed width and thicknesses were taken at the mid portion and the widest part, respectively, of the seed.
Se realizo un corte con bisturi en el extremo chalazal
bajo microscopio estereoscopico con aumento de 5X (Severin et al., 2004).
In the chalazal
region occurs hypostase which presents strongly staining and thick-walled cells.
Seeds 4 per fruit, compressed, more or less cuadrangular in outline with a micropilar neck and a chalazal
beak, 9-10 mm long, 5-6 mm wide and 1 mm thick.
0,7 mm wide, flattened, not thickened towards the apex, yellowish; anthers linear, subdorsifixed, slightly sagittate, with a thick green connective and dark brown to blackish thecae, pollen yellow; ovary conical, the lower 1/3 (= nectary tissue) sunk into the receptacle, yellowish, nectary tissue orange, the superior part 7 mm long; ovules white, the flat chalazal
appendage about half as long as the ovule proper; style ca.
Changes in chalazal
cell walls and in the peroxidase enzymes of the crease region during grain development in barley.
We've all heard of physical dormancy, but the discussion in Chapter 3, along with information in a table and a figure, brings all the information together and helps to explain (and us to remember) differences between strophioles or chalazal
Each megaspore initiates a pattern of free nuclear development, but only the gametophyte located in the most chalazal
(basal) position will continue to develop and eventually participate in fertilization [ILLUSTRATION FOR FIGURE 3C OMITTED].