|Wood, Delilah - De|
Submitted to: United States-Japan Cooperative Program in Natural Resources
Publication Type: Proceedings
Publication Acceptance Date: 11/1/2003
Publication Date: 11/9/2003
Citation: Wood, D.F., Champagne, E.T., Juliano, B.O., Bechtel, D.B., Ogawa, Y., Inglesby, M.K., Gray, G.M. 2003. Anatomy and histochemistry of the rice grain. United States Japan Natural Resources, Cooperative Program in Natural Resources Food and Agriculture Panel. Interpretive Summary: This paper presents basic anatomy and histochemical data on rice grain including the hull and how the structures interrelate. The work compares some of the common features as well as some of the differences between various rice cultivar types. The information should be useful to rice plant breeders.
Technical Abstract: Rice (Oryza sativa L.) is harvested as paddy rice, or spikelets. Each spikelet consists of a caryopsis, the brown rice grain, and the surrounding hull. The hull consists of a palea and lemma which are subtended by two the upper and lower glumes and the supporting rachilla. The lemma and palea consist of silica-containing outer epidermis, highly lignified sclerenchyma, spongy parenchyma and an inner epidermis. The caryopsis consists of a seed and a tightly adherent pericarp. The pericarp is comprised of a thin cuticle covering the epidermis; several layers of partly crushed, "spongy" parenchyma; cross and tube cells. The seed includes the testa, nucellus. embryo and endosperm. The testa and nucellus consist of a siingle crushed layer of cells, the testa and nucellar cuticles and the remains of the nucellar cells. The embryo consists of the scutellum embryonic axis and various sheathing structures containing storage proteins, lipids and meristematic tissues. The aleurone layer is tightly bound to the starchy endosperm and contains storage proteins with globoid inclusions. The starchy endosperm contains parenchyma cells filled with compoundd starch granules and protein bodies.