INTRODUCTION

POACEAE (Gramineae) – Grass Family

Grasses are the most versatile plant life-forms on the earth belong to class Monocotyledons. They occupy large tracts of land and are evenly distributed in all parts of the world.  They belong to Family Poaceae .This family ranks at fifth place, the first four places being occupied respectively by Compositae, Leguminosae, Orchidaceae and Rubiaceae. They germinate in every type of soil and under all climatic conditions. In certain places grasses form a leading feature of the flora. Grasses do not like shade; they are not usually abundant within the forests either as regards the number of individuals, or of species. But in open places they do very well and sometimes whole tracts become grass-lands.
CLASSIFICATION
Class- Monocotyledons

·         Embryo with single cotyledon.

·         Venation parallel.

·         Flower trimerous.

Series- Glumaceae

·         Flower solitary, sessile in the axil of bract and enclosed in glumes.

·         Perianth of the scale or none.

·         Ovary superior, unilocular with one ovule. 

Family- Divided into two Families
1. Cyperaceae

·         Perinnial herbs with 3-angled stem.

·         Flowers in spikelet’s, naked and Hermaphrodite or unisexual.

·         Leaves with sheathing base without lemma and palea.

·         Perianth absent and stigma linear.

·         Gynoecium 2-3 carpellary, syncarpous, superior and unilocular with one ovule.

·         Nut trigonous.

2. Poaceae

·         Herbs or shrubs with hollow internodes and jointed stem

·         Leaves distichous with distinct sheath enclosing the stem and linear blade with often a ligule at their junction.

·         Flowers in spikelet with two glumes, reduced and enclosed in lemma and palea.

·         Perianth represented by lodicules, ovary superior and stigmas feathery

·         Fruit caryopsis