« Previous Abstract"[Involvement of monoamine oxidases in formation of 4-hydroxyphenylethanol, major component of tribulin A]"    Next AbstractEvidence of floral rewards in Brasiliorchis supports the convergent evolution of food-hairs in Maxillariinae »

Plant Biol (Stuttg)

Title:		At daybreak--reproductive biology and isolating mechanisms of Cirrhaea dependens (Orchidaceae)
Author(s):		Pansarin ER; Bittrich V; Amaral MC;
Address:		"Departamento de Botanica, Instituto de Biologia, Universidade Estadual de Campinas, Caixa Postal 6109, Campinas, Sao Paulo 13083-970, Brazil. epansarin@uol.com.br"
Journal Title:		Plant Biol (Stuttg)
Year:		2006
Volume:		8
Issue:		4
Page Number:		494 - 502
DOI:		10.1055/s-2006-923800
ISSN/ISBN:		1435-8603 (Print) 1435-8603 (Linking)
Abstract:		"Floral biology, reproduction, pollinator specificity, and fruit set of Cirrhaea dependens were recorded in forest areas of Southeastern Brazil. Cirrhaea dependens is a lithophytic or epiphytic herb occurring very sparsely below dense canopies. Nearly all the flowers of a single plant open simultaneously before dawn. They are short-lasting and offer floral fragrances as rewards, which are collected by male euglossine bees. Observations carried out in mesophytic forests at Serra do Japi revealed that Euglossa VIRIDIS is their principal pollinator, with Eufriesea violacea a sporadic co-pollinator. Visitation started soon after flower opening, and attractiveness remained high for about 2 h, decreasing abruptly at sunrise. Flower anthesis with subsequent fragrance release seems to be correlated with bee attraction. Observations using chemical baits were carried out at Serra do Japi, and in the Atlantic Rain Forest of Picinguaba. Three euglossine species were captured with pollinaria of C. dependens in Picinguaba, whereas only E. violacea was attracted in Serra do Japi. In Picinguaba, C. dependens occurs sympatrically with C. saccata and C. loddigesii. Each species attracted different pollinators. The specificity and resulting reproductive isolation are due to the production of different odours by each orchid species. Cirrhaea dependens is self-compatible but pollinator-dependent. The reproductive success was low and appears to result from a combination of factors discussed here, such as the production of short-lived flowers, presence of floral mechanisms avoiding self-pollination, non-synchronization of flower phases among plants, and populations with few and sparsely distributed individuals"
Keywords:		Animals Bees/physiology Flowers/anatomy & histology/*physiology Fruit/physiology Male Odorants Orchidaceae/anatomy & histology/*physiology Pollen/physiology Reproduction/physiology Time Factors;
Notes:		"MedlinePansarin, E R Bittrich, V Amaral, M C E eng Research Support, Non-U.S. Gov't England 2006/08/15 Plant Biol (Stuttg). 2006 Jul; 8(4):494-502. doi: 10.1055/s-2006-923800"