2025/09/01 by Carol C. Baskin, Jerry M. Baskin · 1 voice · 1 citation
Agricultural and Biological Sciences · #Botanical Research and Applications #Plant Diversity and Evolution #Seed Germination and Physiology
paper · pdf · doi:10.1017/s0960258525100068
openalex publication_date 2025/09/01 · openalex created_date 2025/10/21 · openalex updated_date 2026/07/29
Abstract The Malvaceae is the 12 th largest angiosperm family with ten subfamilies, 243 genera and c. 4000 species of trees, shrubs, herbs and a few climbers. Subfamilies originated in the Upper Cretaceous-Palaeocene, and their divergence times range from 71.6 to 33.0 Ma. Seeds have a folded, investing or spatulate embryo, and they may be nondormant (ND) or have physical (PY) and/or physiological (PD) dormancy. Of the 365 species for which dormancy/germination data were found, 34.0% had ND seeds and 46.6% PY; 1.6%, PD&ND; 13.1%, PY&ND; and 4.7% PY+PD. Seeds with PY have a palisade layer of Malpighian cells (with a light line) in the outer epidermis of the inner integument, and a chalazal plug is the water gap. Seeds of 168 species of wet tropical trees, in all ten subfamilies, were ND (57.2%) or had PY (19.7%), but seed collections of many species were a mixture of ND & PY (20.2%); 2.9% had PD&ND. We found 13 tree species in wet tropics with recalcitrant seeds and 57 species in 28 genera in seven subfamilies in various habitats with persistent soil seed banks. Malvoideae is the most species rich and widely distributed subfamily and is found in tropical and temperate regions but rarely in subalpine/boreal or Arctic/alpine tundra vegetation. Few if any Malvaceae, in particular Malvoideae, grow as herbaceous perennials in tundra vegetation; possible reasons for this are considered.