BOTA2000 Study Guide - Final Guide: Apomixis, Chaff, Fabaceae
Document Summary
Outline the distribution, major taxa and adaptive traits of any family of flowering plants. 8700 species in 650 genera cosmopolitan (desert, tropics, poles) grasslands periodic droughts, frequent fires, under certain grazing, soil conditions. 24 % of earth"s vegetation dominated by grasses. 70 % of world"s far(cid:373)la(cid:374)d pla(cid:374)ted i(cid:374) crop grasses. 50 % of humanities calories from grasses. Cultivation for 10 000 years global production sugar (1), wheat (2), rice (3), maize (4), barley & sorghum in top 12 grasses used for livestock fodder, erosion control, turf production, alcohol production, paper, pulp, construction. Leaves, alternate, 2 ranked, sheaths open, tightly encircling stem, small ligule at base of blade, margins overlapping. Flowers small, bisexual or unisexual, wind-pollinated, much reduced, each supported by two bracts (lemma & palea), arranged in spikelets, each with two basal bracts (glumes), arranged in spikes or panicles. Grass spikelet protects flowers but permits pollination. Spikelets have many adaptations for fruit dispersal.
