Presentation on theme: "Rosaceae Ann Bond March 15, 2001. Rosaceae Taxonomy Class Magnoliopsida Subclass Rosidae Order Rosales Family Rosaceae –4 Subfamilies : Spiraeoideae Maloideae."— Presentation transcript:
Maloideae Important genera: Pyrus (pear), Malus (apple), Sorbus (Mt. Ash) Small, branching, deciduous shrubs and trees Leaves: simple or pinnately compound, toothed, with stipules
Maloideae Infloresences: cyme or corymb Gynoecium: inferior ovary, syncarpous (fused) of 2-5 carpels, ovary adnate to hypanthium Hypanthium-floral tube formed from the receptacle Androecium: many Fruits: Accessory: pome Spur shoots- a short branch bearing fruit buds
Prunoideae Important genera: Prunus (almond, cherry, nectarine, peach, apricot, and plum) Trees and shrubs (generally small); showy white or pink flowers Leaves: simple with stipules
Prunoideae Infloresences: corymb, umbel, raceme Gynoecium: superior ovary, 1 pistil, hypanthium not adnate to ovary Androecium: many Fruits: drupes Stipules- paired appendages sometimes located at the base of leaf petiole.
Rosoideae Important genera: Rubus (raspberry), Rosa (rose), Potentilla (cinquefoil), Fragaria (strawberry) Upright or climbing shrubs, often with thorny stems; stolons or runners in Fragaria Leaves: compound(pinnate, palmate, or alternate) with stipules
Rosoideae Infloresences: solitary, corymb, raceme Gynoecium: superior ovary, 10 or more pistils (each pistil becomes a simple fruit) Androecium: many Fruits: aggregate accessory: achene, drupe, hip Stolons-modified, elongated, horizontal stems that creep along the ground. They root at the nodes or tip to give rise to new plants.
Fruits of the Rosaceae: General Pericarp: the wall of the ovary in fleshy fruits The thickness of the pericarp increases just prior to pollination and fertilization The pericarp consists of 3 layers: –Exocarp: outer layer of the pericarp –Mesocarp: middle layer; often fleshy –Endocarp: inner layer of pericarp
Fruits: Spiraeoideae Usually a follicle (sometimes called a capsule) Follicle-simple, dry fruit developed from a single pistil that dehisces along one margin Importance-the plants of this subfamily are used as ornamentals
Fruits: Maloideae Pome is predominant fruit in this subfamily Pome-simple accessory fruit with more than one carpel –There are several seeds –Accessory fruits are derived from non-ovarian tissue –Apples, pears, and chokeberries hang from their pediuncle Importance- fruits are used for fresh eating, processing, and plants are used as ornamentals
Fruits: Prunoideae Drupes are the predominant fruit Drupe- a stone-fruit having a hard inner pit that contains one seed and a fleshy outer layer Importance: the edible fruits of this subfamily are used for fresh eating and processing
Fruits: Rosoideae Achene, hip, and druplets Achene-dry one seeded fruit with a firm close fitting wall –Pericarp is free from the seed –Strawberry is considered a aggregate fruit of achenes. –Each pistil becomes a fruit and the receptacle swells and surrounds the fruit
Hip- an aggregation of achenes surrounded by the receptacle plus hypanthium; considered an accessory fruit Druplets-a cluster of fruits clearly traceable to separate pistils of the same flower and inserted on a common receptacle –The receptacle swells and surrounds the fruits Importance- fruits are eaten fresh and used for pies
References Brickell, Christopher and Zuk, Judith. The American Horticultural Society, A-Z Encyclopedia of Garden Plants. DK Publishing: New York, New York. 1997. Harris, James G. and Harris, Melinda Woolf. Plant Identification Terminology. Spring Lake Publishing: Spring Lake, Utah. 1997. Jones, Samuel and Luchsinger, Arlene. Plant Systematics. McGraw-Hill, Inc: New York, New York. 1985. Wood, Marcia. “Strawberry Growers Test Methyl Bromide Alternatives” ARS. Vol 49, No 1, January, 2001.