MORPHOLOGICAL ASPECTS OF FOUR BUZZ-POLLINATED SPECIES OF THE TRIBE CASSIEAE (CAESALPINIACEAE)
The morphology, phases, rewards, attractants, visitors, pollen and P/O ratio of four buzz-pollinated species of the tribe Cassieae were analysed in order to establish their floral biology and to test the presence of morphological androeciums differentiation. We wanted to know if the morphological differences, when observed, reflected functional differences between the groups of stamens. Results allowed us to establish that both genera share a group of characteristics that place them in the buzz-pollination syndrome. The pollinators are bumblebees able to vibrate the stamens leading to nothotribic or sternotribic deposition of pollen. The morphological androeciums differences are more evident in Senna than in Chamaecrista, as well as the reflected functional differences: the medium stamens play a nutritional role while the longest play a reproductive one. The P/O ratio was extremely high for all the species treated and pollen production was also high. It may be related to the visitor's behaviour and would act as a reproductive strategy to assure an effective pollen deposition.
Laporta, C. and Palacios, R.A. (2001). MORPHOLOGICAL ASPECTS OF FOUR BUZZ-POLLINATED SPECIES OF THE TRIBE CASSIEAE (CAESALPINIACEAE). Acta Hortic. 561, 179-183
buzz-pollination, floral biology, Caesalpiniaceae, Senna, Chamaecrista