Transcript Cereal
Cereal Poaceae Cereals • Genetically – originated from Asia, Central and South America and Africa. Good crop: – – – – – – – – – Palatibility Quantity satisfaction Nutritional value Digestibity Toxic property Seasonal availabilty Storage life Preparation requirement presentation Cereals • Named after Ceres, the Roman Goddess of agriculture • Poaceae members • Grain is a fruit – caryopsis • 70% of Earth’s farmland – feeding humans and animals • Three major categories – Major cereal – Minor cereal – Wild cereal • Pseudocereal – non-poaceae members Cereals • 30,000 yrs ago paleolithic people collected seeds. Still followed by aborigines of Australia • Delta of Nile and fertile Cresent – 8000 7000 BC • Wide spread in Mediterranean basin, Western Asia and Western Europe – 4000 yrs Vegetative • Vegetatively, grasses have several features. – The stems are round in cross section, the internodes are hollow, the nodes are solid, – the leaves are flat and 2-ranked, – the bases of the leaves have an open sheath that encircles the stem, and t – here is often a ligule present at the juncture of the sheath and the leaf blade. Inflorescence • The inflorescences of grasses also have distinctive characteristics. – The basic unit of an inflorescence is a spikelet, which contains 1 or more flowers. – At the base of the spikelet are 2 bracts called glumes. – The spikelets can be arranged in panicles, racemes, spikes, or other types. Poaceae • The flowers of Poaceae are small, lack petals, and are pollinated by wind. The 2 sepals are modified into lodicules. There are 3 stamens that hang down and the anthers shed pollen into the wind. The syncarpous gynoecium has 2 carpels, the ovary is superior, the styles are featherlike to catch pollen from the wind, and the ovary is 1-locular with 1 basal ovule. Poaceae (The grass family) • Caryopsis - A one-seeded dry indehiscent fruit (achene) with the thin pericarp adherent to the seed.