Question

to study different types of seed germination
pls help on my project....​

Answer 1

Explanation:

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 . Among dicotyledons, gram, pea groundnut are some common examples of hypogeal germination.

Distinction between epigeal and hypogeal type of germination

In monocotyledons (e.g., wheat, maize, rice, coconut) radicle and plumule come out by piercing the coleorrhiza and coleoptile respectively. The plumule grows upward and the first leaf comes out of the coleoptile. The radicle forms the primary root which is soon replaced by many fibrous roots.

(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

Successive stages of hypogeal germination of dicotyledonous exalbuminous seed of pea

(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 outThree seminal roots develop from above the radicle (but variation in number). The radicle and seminal roots with two branches persist throughout the life of the plant. Adventitious roots are formed from the lowermost nodes above the mesocotyl

Successive stages of hypogeal germination of monocotyledonous seed

(iii) Germination of Wheat Grain:

Details of wheat grain germination are similar to those of maize grain germination. Wheat grain shows hypogeal germination.