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Matias R, Oliveira ASD, Furtado MT, Sá T, Rodrigues EB, Oliveira PED, Consolaro H. Sistema reprodutivo atípico de duas espécies de Rubiaceae: distilia com autoincompatibilidade parcial no morfo brevistilo? RODRIGUÉSIA 2016. [DOI: 10.1590/2175-7860201667207] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Resumo Espécies distílicas possuem populações com dois morfos florais. O morfo longistilo possui flores com pistilos longos e estames curtos e o morfo brevistilo, pistilos curtos e estames longos. Normalmente, os morfos apresentam um sistema heteromórfico de incompatibilidade e os morfos estão em uma razão de 1:1 (isopletia) nas populações. Diferentes variações podem ser encontradas em espécies distílicas, como a presença de autocompatibilidade, anisopletia e variações no nível de reciprocidade entre anteras e estigmas dos dois morfos. O objetivo desse trabalho foi investigar a ocorrência das características distílicas em duas espécies de Rubiaceae. Para isso, a razão dos morfos, a hercogamia recíproca, o sistema de incompatibilidade e os visitantes florais de Psychotria deflexa e Declieuxia fruticosa foram estudados. Ambas as espécies apresentaram os dois morfos em proporção semelhante, altos valores de reciprocidade entre a altura dos verticilos sexuais dos morfos florais e apenas insetos como visitantes florais. O morfo brevistilo das duas espécies apresentou autoincompatibilidade parcial. Dentro de Rubiaceae, mesmo em grupos filogenéticos distintos, o relaxamento ou quebra da distilia parece ocorrer em padrões similares e comumente tal variação é mais comum no morfo longistilo. Para as espécies estudadas, mesmo com a pseudocompatibilidade do morfo brevistilo, as populações apresentaram proporção igual dos morfos, indicando que fatores como a alta hercogamia recíproca e, possivelmente, o serviço de polinização podem promover a manutenção da isopletia característica da distilia.
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Affiliation(s)
| | | | | | - Túlio Sá
- Universidade Federal Rural de Pernambuco, Brazil
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Watanabe K, Yang TYA, Nishihara C, Huang TL, Nakamura K, Peng CI, Sugawara T. Distyly and floral morphology of Psychotria cephalophora (Rubiaceae) on the oceanic Lanyu (Orchid) Island, Taiwan. BOTANICAL STUDIES 2015; 56:10. [PMID: 28510819 PMCID: PMC5432894 DOI: 10.1186/s40529-015-0091-9] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/15/2014] [Accepted: 04/28/2015] [Indexed: 05/28/2023]
Abstract
BACKGROUND Psychotria cephalophora Merr. (Rubiaceae), a shrub in oceanic islands of Taiwan and the Philippines, appears to be distylous, but distyly is usually rare on oceanic islands. To elucidate the functional breeding system of P. cephalophora can improve our understanding of plant reproductive ecology on oceanic islands. RESULTS Field investigations on Lanyu (Orchid Island) off the coast of southeastern Taiwan revealed the flowers to be distylous with short (S)- and long (L)-styled morphs, with only one morph per individual. Laboratory observations revealed that both morphs had stainable pollen grains and indicated dimorphism in stigmatic papillae and pollen size. In hand pollination experiments, the pollen tubes reached the base of the style in intermorph crossing, whereas they rarely penetrated stylar tissue in intramorph crossing and selfing. Open pollinated S- and L-styled flowers produced fruit. CONCLUSIONS The results indicate that the breeding system of P. cephalophora is morphologically and functionally distylous.
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Affiliation(s)
- Kenta Watanabe
- Okinawa National College of Technology, 905 Henoko, Nago 905-2192 Okinawa, Japan
| | - T Y Aleck Yang
- Department of Botany, National Museum of Natural Science, Kuan Chien Rd, Taichung, 404 Taiwan
- Department of Life Science, National Chung Hsin University, Taichung, 402 Taiwan
| | | | - Tai-Liang Huang
- Department of Botany, National Museum of Natural Science, Kuan Chien Rd, Taichung, 404 Taiwan
| | - Koh Nakamura
- Botanic Garden, Field Science Center for Northern Biosphere, Hokkaido University, North 3, West 8, Chuo-ku, Sapporo, 060-0003 Japan
| | - Ching-I Peng
- Biodiversity Research Center, Academia Sinica, Taipei 115, Nangang, Taiwan
| | - Takashi Sugawara
- Makino Herbarium, Graduate School of Science, Tokyo Metropolitan University, 1-1 Minami-Ohsawa, Hachioji, Tokyo, 192-0397 Japan
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Watanabe K, Sugawara T. Is heterostyly rare on oceanic islands? AOB PLANTS 2015; 7:plv087. [PMID: 26199401 PMCID: PMC4570599 DOI: 10.1093/aobpla/plv087] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/26/2015] [Accepted: 07/03/2015] [Indexed: 05/28/2023]
Abstract
Heterostyly has been considered rare or absent on oceanic islands. However, there has been no comprehensive review on this issue. Is heterostyly truly rare on oceanic islands? What makes heterostyly rare on such islands? To answer these questions, we review the reproductive studies on heterostyly on oceanic islands, with special emphasis on the heterostylous genus Psychotria in the Pacific Ocean as a model system. Overall, not many reproductive studies have been performed on heterostylous species on oceanic islands. In Hawaiian Psychotria, all 11 species are thought to have evolved dioecy from distyly. In the West Pacific, three species on the oceanic Bonin and Lanyu Islands are distylous (Psychotria homalosperma, P. boninensis and P. cephalophora), whereas three species on the continental Ryukyu Islands show various breeding systems, such as distyly (P. serpens), dioecy (P. rubra) and monoecy (P. manillensis). On some other Pacific oceanic islands, possibilities of monomorphy have been reported. For many Psychotria species, breeding systems are unknown, although recent studies indicate that heterostylous species may occur on some oceanic islands. A shift from heterostyly to other sexual systems may occur on some oceanic islands. This tendency may also contribute to the rarity of heterostyly, in addition to the difficulty in colonization/autochthonous evolution of heterostylous species on oceanic islands. Further investigation of reproductive systems of Psychotria on oceanic islands using robust phylogenetic frameworks would provide new insights into plant reproduction on oceanic islands.
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Affiliation(s)
- Kenta Watanabe
- Okinawa College, National Institute of Technology, 905 Henoko, Nago, Okinawa 905-2192, Japan
| | - Takashi Sugawara
- Makino Herbarium, Graduate School of Science, Tokyo Metropolitan University, 1-1 Minami-Ohsawa, Hachioji, Tokyo 192-0397, Japan
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Bramow C, Hartvig I, Larsen SB, Philipp M. How a heterostylous plant species responds to life on remote islands: a comparative study of the morphology and reproductive biology of Waltheria ovata on the coasts of Ecuador and the Galápagos Islands. Evol Ecol 2012. [DOI: 10.1007/s10682-012-9588-9] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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Machado IC, Lopes AV, Sazima M. Contrasting bee pollination in two co-occurring distylic species of Cordia (Cordiaceae, Boraginales) in the Brazilian semi-arid Caatinga: generalist in C. globosa vs. specialist in C. leucocephala. AN ACAD BRAS CIENC 2010; 82:881-91. [DOI: 10.1590/s0001-37652010000400010] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2009] [Accepted: 03/31/2010] [Indexed: 11/22/2022] Open
Abstract
In this study we compare the reproductive biology of Cordia globosa and C. leucocephala (Cordiaceae, Boraginales; formerly referred to Boraginaceae) to understand the functioning of the floral morphs and the relations with their effective pollinators. The species are synchronopatric, distylic, and self-incompatible. Though they share melittophilous traits, the main visitor and pollinator of C. globosa was the generalist and exotic bee Apis mellifera, while the only one of C. leucocephala was the oligoletic bee Ceblurgus longipalpis. These two latter species are restricted to the Caatinga of NE Brazil, contrasting with the wide distribution of Cordia globosa. While the fruit-set for C. globosa was high, independently if the pollen donor/stigma receptor was a pin (long-styled) or thrum (short-styled) individual, in C. leucocephala the fruit-set was low and occurred only when a thrum individual was the pollen donor. This raises the possibility of this species moving towards dioecy. The high natural fruit-set of C. globosa confirms the generalist bee as its effective pollinator. The low fruit-set after manual crosses in C. leucocephala may be due to low pollen viability. Additionally, the low natural fruit-set (two times lower than after crosses) may be related with the foraging behavior of the specialist pollinator.
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Koch AK, Silva PCD, Silva CA. Biologia reprodutiva de Psychotria carthagenensis (Rubiaceae), espécie distílica de fragmento florestal de mata ciliar, Centro-Oeste do Brasil. RODRIGUÉSIA 2010. [DOI: 10.1590/2175-7860201061314] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Resumo Este estudo teve por objetivos analisar a fenologia de floração, a biologia e a morfologia floral, o sistema e o sucesso reprodutivo dos morfos florais de Psychotria carthagenensis Jacq. O período de floração se estendeu de maio (estação seca) a janeiro (estação chuvosa). A floração dos morfos florais foi sincronizada e o número médio de inflorescências, de botões em pré-antese e de flores abertas por indivíduos foram semelhantes. A antese das flores de ambos os morfos foi de 12 horas. Houve diferença significativa no comprimento da corola, dos lobos estigmáticos, das anteras e altura do estilete entre os morfos florais. A viabilidade de pólen foi alta entre ambos os morfos. A formação de frutos ocorreu em polinizações intramorfos e intermorfos e não houve diferença significativa na produção de frutos e sementes em tratamentos intermorfos. Os atributos florais analisados sugerem que os dois morfos contribuem similarmente para a manutenção da espécie na área de estudo.
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Wu X, Li A, Zhang D. Cryptic self-incompatibility and distyly in Hedyotis acutangula Champ. (Rubiaceae). PLANT BIOLOGY (STUTTGART, GERMANY) 2010; 12:484-494. [PMID: 20522185 DOI: 10.1111/j.1438-8677.2009.00242.x] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
Distyly, floral polymorphism frequently associated with reciprocal herkogamy, self- and intramorph incompatibility and secondary dimorphism, constitutes an important sexual system in the Rubiaceae. Here we report an unusual kind of distyly associated with self- and/or intramorph compatibility in a perennial herb, Hedyotis acutangula. Floral morphology, ancillary dimorphisms and compatibility of the two morphs were studied. H. acutangula did not exhibit precise reciprocal herkogamy, but this did not affect the equality of floral morphs in the population, as usually found in distylous plants. Both pin and thrum pollen retained relatively high viability for 8 h. The pollen to ovule ratio was 72.5 in pin flowers and 54.4 in thrum flowers. Pistils of pin flowers remained receptive for longer than those of thrum flowers. No apparent difference in the germination rate of pin and thrum pollen grains was observed when cultured in vitro, although growth of thrum pollen tubes was much faster than that of pin pollen tubes. Artificial pollination revealed that pollen tube growth in legitimate intermorph crosses was faster than in either intramorph crosses or self-pollination, suggesting the occurrence of cryptic self-incompatibility in this species. Cryptic self-incompatibility functioned differently in the two morphs, with pollen tube growth rates after legitimate and illegitimate pollination much more highly differentiated in pin flowers than in thrum flowers. No fruit was produced in emasculated netted flowers, suggesting the absence of apomixis. Our results indicate that H. acutangula is distylous, with a cryptic self-incompatibility breeding system.
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Affiliation(s)
- X Wu
- Key Laboratory of Plant Resource Conservation and Sustainable Utilization, South China Botanical Garden, Chinese Academy of Sciences, Guangzhou, China
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