Question

To study of difrrent types of seed germination?

Answer 1

Answer:

Type # 1. Hypogeal Germination:

In this kind of germination, the cotyledons do not come out of the soil surface. In such seeds the epicotyl (i.e., part of embryonic axis between plumule and cotyledons) elongates pushing the plumule out of the soil. All monocotyledons show hypogeal germination (Fig. 4.3, 4.4, 4.5). Among dicotyledons, gram, pea (Fig. 4.2), groundnut are some common examples of hypogeal germination.

(i) Germination of Pea Seed:

The seed imbibes water and swells. The radicle comes out and first penetrates the soil and forms root system by giving out secondary branches. It is the epicotyls which grows first. It arches out and carries the plumule above ground. The plumule soon forms the aerial shoot. The cotyledons remain under the soil throughout

(ii) Germination of Maize Grain:

The grain imbibes water from moist soil. The coleorhiza pierces the base of caryopsis (fruit) and appears as a shining knob. After sometimes, the coleorhiza gets ruptured due to growth of radicle. After sometime coleoptile comes out.