Taxonomy : Embryology in Plant Classification | Role of Embryology

Embryology in Plant Classification: 

Embryology is the study of micro and mega sporogenesis, gametophyte development, fertilization development of endosperm, embryo and seed coats. embryological evidence has been used in solving the taxonomical problems at almost all levels. These evidences have resolved the doubtful systematic positions of several taxa. However, the role of embryology in solving taxonomical problems was first brought by a German embryologist, Schnarf in 1931.

          According to Maheswari, Bhojwani and Bhatnagar and Radford some basic embryological characters which have proved to be of special basic embryological characters which have proved to be of special importance in taxonomic considerations include -

1. Presence and type of another tapetum.

2. Development of structure, position, and orientation of ovule.

3. Megasporogenesis and development of embryosac.

4. Form of embryosac.

5. Type of embryosac.

6. Type of embryogeny.

7. Fertilization.

8. Seed coat.

                  

                                  
Role of Embryology :

(1) Dicots and Monocots: Angiosperms are universally divided into dicotyledons and Monocotyledons. The primary classification of angiosperm is based on one major embryological character I.e; the number of cotyledons.

(2) Helobiae:  This monocotyledonous order, treated as a subclass in some recent system of classification, is characterized by the presence of a helobial type of endosperm.

(3) Orchidales:  The distinguishing embryological character of the members of this order is the presence of undifferentiated embryo and very little or no endosperm.

(4) Podostemaceae:  Members of this family are recognized because of the formation of pseudo embryosac, which is formed by nucellar cells.

(5) Lemnaceae:  Phylogenetic studies indicate that Lemnaceae have been derived either from the Helobiales or from the Araceae. But on the basis of the embryological studies, Maheswari suggested that Lamnaceae have been evolved from Araceae, not from Helobiales.

(6) Crassulaceae:  Embryological studies of Crassulaceae suggest that it should be placed in the order Rosales.

      All the above-mentioned examples confirm that embryology plays a definite and significant role in solving taxonomic problems.

               

• Tweet
• Share
• Share
• Share

Related Post