FAMILY POACEAE GRASS FAMILY Cereals and Grasses 25

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FAMILY POACEAE (GRASS FAMILY) • • • Cereals and Grasses (25% of vegetation) 600

FAMILY POACEAE (GRASS FAMILY) • • • Cereals and Grasses (25% of vegetation) 600 genera and 8, 500 species Wheat (Triticum vulgare) Rice (Oryza sativa) Barley (Hordeum vulgare) Oat (Avena sativa) Millet (Pennisetum americanum) Summer grass (Cynadon dactylon) Winter grass (Poa annua)

Ornithopoda Varigata Chasmanthium latifolium ORNAMENTAL GRASSES

Ornithopoda Varigata Chasmanthium latifolium ORNAMENTAL GRASSES

Meadow Grass Sisyrinchium mucronatum

Meadow Grass Sisyrinchium mucronatum

 • • Monocots No Secondary Growth Herbaceous plants Parallel Venation Base of each

• • Monocots No Secondary Growth Herbaceous plants Parallel Venation Base of each leaf forms a sheath Stems (culms) hollow, unbranched Both annual and perennial species occur

 • Source of Gluten (gliadin and glutelin) • Endosperm of grasses • Elasticity

• Source of Gluten (gliadin and glutelin) • Endosperm of grasses • Elasticity of dough • Due to fermentation by yeast, CO 2 trapped • Leavened Bread • High gluten in wheat and rye responsible for Leavened bread

FLOWER • Small, inconspicuous and incomplete • Sepals and petals replaced with lodicules •

FLOWER • Small, inconspicuous and incomplete • Sepals and petals replaced with lodicules • Three stamens and one carpel • Ovary single but two styles and stigmas • Stigma enlarged and feathery • Stamen pendant • Wind-pollination

GRASS FLOWER

GRASS FLOWER

WHEAT • Widely cultivated cereal • Wheat-producing countries Ukraine, U. S, Canada, China, India,

WHEAT • Widely cultivated cereal • Wheat-producing countries Ukraine, U. S, Canada, China, India, Argentina, France, South Africa • Modern Cultivars durum, bread wheat • Durum wheat (Triticum durum) grown in Northern United States, Canada, Europe

Durum wheat

Durum wheat

 • T. durum high gluten content and yields semolina flour (used as spaghetti,

• T. durum high gluten content and yields semolina flour (used as spaghetti, macaroni, and noodles) • Triticum aestivum (Bread wheat) makes 90% of world production • Used in breakfast, bread, pastries • New cultivars constantly being developed

 • • Vitamin A, B 12, C iodine missing • Refined wheat flour

• • Vitamin A, B 12, C iodine missing • Refined wheat flour mixed with wheat • Riboflavin • Niacin • Thiamin

CORN • • Zea mays (maize) summer annual crop Corn in U. S In

CORN • • Zea mays (maize) summer annual crop Corn in U. S In England Corn refers to wheat In Scotland corn refers to oat Amylose and Amylopectin Large chromosome (Barbara Mc. Clintok) Popcorn, Flint, Flour, Dent, Sweet, Waxy and Pod

 • Sweet corn contains high concentration of sugar instead of starch • Waxy

• Sweet corn contains high concentration of sugar instead of starch • Waxy corn relatively new, appeared in China • introduced into U. S (glossy, wax-like appearance) • Source of carbohydrate, fats and proteins • Corn starch, corn oil, corn syrup all processed from corn • Used as biofuel • Color depends upon pigmentation of endosperm, aleurone layer and pericarp)

Waxy Corn (Amylopectin in Endosperm) Pop Corn (Hard kernels with hard starch (more amylose)

Waxy Corn (Amylopectin in Endosperm) Pop Corn (Hard kernels with hard starch (more amylose) surrounding a core of soft starch and endosperms with water

Dent Corn (Successful with hard and soft starch, hard starch along sides and soft

Dent Corn (Successful with hard and soft starch, hard starch along sides and soft to top and centre

Flint Corn (Hard starch in outer part of kernel)

Flint Corn (Hard starch in outer part of kernel)

Sweet Corn (High concentration of sugar instead of starch in cells of endosperm)

Sweet Corn (High concentration of sugar instead of starch in cells of endosperm)

Flour Corn

Flour Corn

Cross section Maize stem

Cross section Maize stem

RICE • Only crop grown extensively for human • More than 2 billion people

RICE • Only crop grown extensively for human • More than 2 billion people in Asia rely on rice as dietary staple • Oryza sativa main cultivated rice • 20 species in this genus known • Cultivated in flooded fields, and paddies • Azolla weed useful for rice (symbiosis)