TY - JOUR AU - Coté, G.G. AU - Gibernau, M. PY - 2012// TI - Distribution of calcium oxalate crystals in floral organs of araceae in relation to pollination strategy T2 - Am. J. Bot. JO - American Journal of Botany SP - 1231 EP - 1242 VL - 99 IS - 7 KW - Araceae KW - Beetles KW - Calcium oxalate KW - Crystal KW - Defense KW - Flowers KW - Herbivory KW - Pollination N2 - Premise of the study: Many flowers are pollinated by potentially hungry insects, yet flowers also contain gametes and embryos which must be protected from predation. Microscopic calcium oxalate crystals in plant tissues have been proposed to protect against herbivory. Aroids, which have an unusual diversity of such crystals, also exhibit diverse pollination strategies. Many species have pollinators that do not feed while visiting the flowers, while other species, especially those pollinated by beetles, offer sterile staminodia as food rewards. We examined flowers of 21 aroid species with various pollination strategies to test the hypothesis that crystals protect vital gametes and embryos while allowing consumption of food bribes.Methods: Aroid inflorescences collected from the field or from greenhouse material were sectioned, cleared, and examined by bright field and polarization microscopy.Key results: All species examined, regardless of pollination strategy, arrayed crystals around unshed pollen and ovules. Less vital tissues, such as odoriferous appendages, had few crystals. Staminodia offered as food to beetle pollinators, however, differed greatly between species in their crystal contents. Some had minimal crystals; some had crystals in patterns suggesting they limit beetle feeding; still others had abundant crystals in no obvious pattern.Conclusions: The results are consistent with crystals protecting against insect predation of gametes and embryos. However, the role of crystals in food-bribe staminodia is unclear. They may limit and direct feeding by beetles in some species, while in others they might have no protective role. © 2012 Botanical Society of America. SN - 00029122 (Issn) UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-84863876007&partnerID=40&md5=89d3f40ecc614a0f7ba436b94805472c N1 - Export Date: 10 August 2012; Source: Scopus; Coden: Ajboa; doi: 10.3732/ajb.1100499; Language of Original Document: English; Correspondence Address: Coté, G. G.; Biology Department, Radford University, Radford, VA 24142-6931, United States; email: gcote@radford.edu ID - Cote+Gibernau2012 ER -