Abstract Detail

Reproductive Processes

CARVALHO-LEITE , LUDIMILA JULIELE  [1], DÁLIA-MAIA , ARTUR CAMPOS  [2], Paulino-Neto , Hipólito Ferreira [1].

Chemical ecology and reproductive biology of Annona cornifolia (Annonaceae) in a Brazilian Savanna.

Annona cornifolia flowers have typical characteristics of cantharophily pollination, such as, floral chamber, nutritive petals and thermogenesis. The aim of this study was to understand the main aspects of the floral and reproductive biology of A. cornifolia, as well as to collect and characterize the chemical composition of floral scents. The study was conducted in two consecutive flowering comprehended from January to February 2018 and December 2018 to February 2019, in Brazilian Savanna area, in Bocaiuva, Northern Minas Gerais State, Brazil. The floral events rhythm was determined monitoring 31 flowersfrom the buds until senescent phase of flowers. Floral buds in pre-anthesis phase were bagged to prevent the pollinator’s visit and they were submitted to the following treatments: cross-pollination (n = 32); spontaneous self-pollination (n = 31); geitonogamy (n = 14); hand self-pollination (n = 4) and control (n = 30). In the population, few flowers showed overlapping of the female and male phases, justifying the low sample size for treatment of manual self-pollination. The Index of Self-Incompatibility (ISI) was calculated and the Reproductive Efficiency (RE). To record the thermogenesis, a digital thermometer was used. Floral scents were collected and analyzed by gas chromatography. A. cornifolia is a hermaphrodite species with protogynous dichogamy. Annona cornifolia did not produce fruits by hand self-pollination or spontaneous self-pollination treatments.  However, 50% of the flowers produced fruits whit geitonogamy and 31,25% with cross-pollination. In this study, surprisingly, no floral visitors were observed in any flower of the control treatment. The ISI was 1.6, indicating that this is a self-compatible species and RE was zero (0), suggesting that there is pollen limitation in this population. Floral rhythm presented two thermogenesis peaks, one in the female and another in the male phase. The higher difference of temperature between flowers and environment was at 5 o'clock in the morning, already ending of male phase (4,74°C). The chemical analysis of floral scents compounds showed the presence of pent-3-yl acetate, a chemical compound previously never reported as floral scent in Annonaceae species. The present study demonstrates that there is a very close relationship between flowers and pollinating beetles, arising from evolutionary processes that shaped this so very specific pollination syndrome. Future researches will be necessary to answer important questions that emerged from this our study about the absence of effective pollinator in the studied population and, especially, on the chemical ecology of the floral volatiles of A. cornifolia.

1 - Universidade do Estado de Minas Gerais, Unidade Passos/ Curso de Ciências Biológicas, Av. Juca Stockler, 1130, Belo Horizonte , Passos, Minas Gerais, 37900-106, Brazil
2 - Universidade Federal de Pernambuco, Programa de Pós‑graduação em Biologia Animal, Av Jornalista Anibal Fernandes, Cidade Universitaria, Recife, Pernambuco, 50740-560, Brazil

beetle pollination
floral volatiles
scent chemistry
Gas chromatography-mass spectrometry (GC-MS)
Pollen limitation
reproductive success
Breeding System
Annona cornifolia.

Presentation Type: Poster
Session: P, Reproductive Processes Posters
Location: Virtual/Virtual
Date: Thursday, July 30th, 2020
Time: 5:00 PM Time and date to be determined
Number: PRP008
Abstract ID:879
Candidate for Awards:None

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