Investigation on reproductive characteristics of Polygonatum cyrtonema / 中国中药杂志

The study is aimed to investigate the reproductive biology characteristics of Polygonatum cyrtonema, especially including phenology, flower bud differentiation, flowering timing, floral traits, pollen vigor and stigma receptivity. The results showed that P. cyrtonema forms inflorescence before the leaves spread. In the wild, P. cyrtonema is mainly pollinated by insects such as bumblebees, with a seed setting rate of 65.12%. The seed setting rate of indoor single plant isolation or self-pollination enclosed by parchment paper bag is 0, indicating that it is self-incompatible. In Lin'an city, seedlings begin to emerge from mid-March to early April(the temperature is higher than 7.5 ℃), buds begin to emerge from the end of March to mid-April, and then undergo the full bloom stage from mid-to-late April, and the final flowering stage from the end of April to mid-May. The whole flowering period lasts 36 to 45 days. There are obvious differences in the phenology of different provenances. The flowers come into bloom from the base to the top along the aboveground main axis, which usually contain 4-22 inflorescences with(2-) 4-10(-21) flowers per inflorescence. The flowering pe-riod for a single plant is 26-38 days. The single flower lasts about 20-25 days from budding to opening and withers 2 days after pollination, and then the ovary will gradually expand. If unpollinated, it will continue to bloom for 3-5 days and then wither. Flower development period is significantly related to pollen vigor and stigma remittance. The pollen viability is the highest when the flower is fully opened with anthers gathering on the stigma, and the receptivity is the strongest when the stigma protrudes out of the perianth and secretes mucus. The fruits and seeds ripen in October, and proper shading can ensure the smooth development and maturity of the seeds. This study provides a basis for the hybrid breeding and seed production of P. cyrtonema.

SEX EXPRESSION, BREEDING SYSTEM AND POLLINATORS OF Piper caldense (PIPERACEAE) IN THE BRAZILIAN ATLANTIC FOREST / Expresión sexual, sistema reproductivo y polinizadores de Piper caldense (Piperaceae) en un bosque Atlántico

ABSTRACT Neotropical Piper species have bisexual flowers. Such reproductive trait is considered basal in this pantropical genus. However, neotropical species having unisexual (staminate) flowers along with bisexual ones have also been reported. Dichogamy is common in the genus, associated with either self-compatibility or -incompatibility, as well as with entomophily. We analyzed a natural population of Piper caldense in a Atlantic Forest area (Viçosa municipality, Minas Gerais state, southeastern Brazil). Preliminary observations indicated that the species produces two flower types. We analyzed flower sex in spikes of 50 plants. We obtained additional information through morphological and anatomical studies and scanning electron microscopy analyses. The longevity and exposure dynamics of stigmatic papillae and the pollen release sequence of all four stamens were investigated to verify the degree of dichogamy. Pollination tests were performed, pollinators were identified and their visitation frequency was recorded. Piper caldense has both bisexual and staminate flowers, each flower type being located on separate spikes. These spikes occurred on the same plant, thus indicating andromonoecy; furthermore, plants having only spikes with staminate flowers were also observed. This gender had not yet been reported to the genus. Gradual and sequential exposure of stigmatic papillae associated with asynchronous pollen release (one stamen a day) resulted in incomplete protogyny. Hand pollination tests showed that the species is self-incompatible. Social bees, mainly Apis mellifera and Melipona spp., were the major pollinator group. Our study reinforces the need to associate morphological analysis with floral biology and indicates future changes in studies addressing reproductive traits associated with the phylogeny of the Piper genus.

RESUMEN Las especies neotropicales de Piper presentan flores bisexuales, condición considerada basal al interior de este género pantropical. Sin embargo, fueron observadas especies neotropicales con flores unisexuales (estaminadas), además de las bisexuales. La dicogamia es común en el género y se encuentra asociada a la autocompatibilidad o incompatibilidad, al igual que la entomofilia. Fue analizada una población natural de Piper caldense en un área de bosque Atlántico (municipio de Viçosa, Minas Gerais, sureste de Brasil). Las observaciones preliminares indicaron que esta especie produce dos tipos florales, para lo cual fue analizada la sexualidad de las flores en 50 espigas a través de estudios morfológicos, anatómicos y análisis con microscopia electrónica de barrido. La longevidad y dinámica de exposición de las papilas estigmáticas y la secuencia de liberación de los granos de polen en los cuatro estambres fueron observados para verificar el grado de dicogamia. El sistema reproductivo se evaluó mediante el test de autopolinización espontánea y polinización abierta. Los visitantes florales fueron identificados y se registró su frecuencia de visita. Piper caldense presenta flores bisexuales y estaminadas, cada tipo floral se encuentra en espigas separadas. Estas espigas se encuentran en la misma planta, lo que indica que es andromonoica; adicionalmente, fueron observadas plantas que solo presentaban espigas con flores estaminadas, lo que se constituye en una combinación sexual inédita para el género. La exposición gradual y secuencial de las papilas estigmáticas asociada con la liberación asincrónica de los granos de polen (un estambre por día) indica una protoginia incompleta. Los test de polinización mostraron que la especie es autoincompatible. Las abejas sociales, principalmente Apis mellifera y Melipona spp., fueron los polinizadores principales. Este estudio refuerza la necesidad de asociar los analisis morfológicos con la funcionalidad de las estructuras florales, además indica los cambios futuros en estudios que abordan características reproductivas asociadas a la filogenia de las especies de Piper.

Reproductive biology of endemic Solanum melissarum Bohs (Solanaceae) and updating of its current geographic distribution as the basis for its conservation in the Brazilian Cerrado / Biologia reprodutiva da endêmica Solanum melissarum Bohs (Solanaceae) e atualização da distribuição geográfica atual, como base para a sua conservação no Cerrado Brasileiro

Abstract The genus Solanum (family Solanaceae) includes more than 1400 species and has buzz-pollinated flowers with poricidal anthers. The present study aimed to describe the distribution, breeding system and pollination mechanism of Solanum melissarum, a species endemic to Brazil. The study of breeding system was conducted in an urban forest fragment in Jataí, GO. Distribution data were gathered from floristic surveys and digital plant databases. The floral morphology and the pollination mechanism were studied on through field observations and preserved flowers. The breeding system was determined through hand pollination treatments. The species has a distribution only in the Brazilian Atlantic forest coastal, and this study provides the first records of S. melissarum for the state of Goiás. The pendulous flowers have poricidal anthers close to the stigma, with membranous thecae joined by a connective bearing osmophores that attract males of Euglossa cordata bees. As they collect fragrances, the bees press the thecae and pollen is released through a bellows mechanism. Based on the hand-pollination treatments, this species is self-incompatible. Isolated forest fragments may not include enough pollinators to ensure the pollination of plants with specialized systems. However, they are essential for the conservation of species with interesting phytogeographic patterns, such as the vicariance observed in S. melissarum, and for the conservation of regional diversity.

Resumo O gênero Solanum (família Solanaceae) inclui mais de 1400 espécies e apresenta polinização vibrátil e flores com anteras poricidas. O estudo tem o objetivo de descrever a distribuição, sistema reprodutivo e o mecanismo de polinização de Solanum melissarum, uma espécie endêmica do Brasil. O estudo da biologia reprodutiva foi conduzido em um fragmento florestal urbano em Jataí, GO. As informações de distribuição foram obtidas através de trabalhos florísticos e de banco de dados digitais de plantas. A morfologia floral e o mecanismo de polinização foram estudados através de observações diretas em campo e em flores preservadas. O sistema reprodutivo foi determinado a partir de tratamentos de polinização manual. A espécie apresentava distribuição somente na Mata Atlântica litorânea brasileira, e este estudo demonstrou o primeiro registro de S. melissarum para o estado de Goiás. As flores são pendentes e com anteras poricidas próximas ao estigma, com tecas membranosas envoltas por um conectivo giboso com osmóforos que atraem machos da abelha Euglossa cordata. Na coleta de fragrâncias, as abelhas pressionam as tecas e o polén é liberado por um mecanismo de fole. Baseado nos tratamentos de polinização manual, a espécie é autoincompatível. Fragmentos florestais isolados podem não incluir polinizadores suficientes para garantir a polinização das plantas com sistemas especializados, no entanto, eles são essenciais para a conservação de espécies com padrões fitogeográficos interessantes, como o vicariância observada em S. melissarum, e também para a conservação da diversidade regional.

Biologia reprodutiva e ausência de frutificação de Aloe saponaria (Aiton) Haw. (Xanthorrhoeaceae) fora do local de origem / Reproductive biology and absence of fruiting of Aloe saponaria (Aiton) Haw. (Xanthorrhoeaceae) outside its place of origin

RESUMO O gênero Aloe, originário principalmente da África, tem atualmente uma ampla distribuição no mundo. No entanto, são poucas as regiões que têm realizado estudos quanto ao sistema reprodutivo. O objetivo do presente trabalho foi analisar as características e o comportamento reprodutivo de Aloe saponaria em Florianópolis, Santa Catarina. Foram conduzidos estudos sobre sua morfologia e biologia floral, visitantes florais e sistema reprodutivo. Esta espécie apresentou uma inflorescência por planta, com um comprimento de 105 ± 0,1 cm e 267 ± 92,7 flores. A razão pólen/óvulo sugere que a espécie é xenogâmica. O volume e concentração de sólidos solúveis totais do néctar potencial foi 16,6 ± 6,3 μL e 22 ± 2,4 °Brix respectivamente. O néctar instantâneo não apresentou diferenças significativas nos períodos avaliados (9:00h e 15:00h) e o estigma permaneceu receptivo até o segundo dia após a antese. Foram coletados 110 insetos visitantes florais, dos quais 61,8% foram indivíduos de Trigona spinipes. Entretanto, nos testes de polinização não foi observada frutificação efetiva, indicando que a propagação vegetativa é o principal tipo de reprodução usado nessa população. Isto pode estar relacionado a um mecanismo de autoincompatibilidade esporofítica, a anormalidades cromossômicas durante a formação do pólen, as condições climáticas, e a escassa variabilidade genética no local de estudo.

ABSTRACT The Aloe genus, originating mainly from Africa, currently has a wide distribution in the world. However, in few regions studies about the reproductive system have been carried on. The aim e of this study was to analyze the characteristics and reproductive performance of the Aloesaponaria in Florianópolis, Santa Catarina. The morphology, floral biology, flower visitors and the reproductive system were determined. The plants presented an inflorescence per plant, with 105 ± 0,1 cm in length and 267 ± 92.7 flowers. The pollen/ovule ratio suggested that the species is xenogamic. The volume and concentration of total soluble solids in the potential nectar were 16.6 ± 6.3 μL and 22 ± 2.4°Brix, respectively. The instant nectar showed no significant differences between the evaluated periods (9:00h and 15:00h) and the stigma remained receptive until the second day the after anthesis. 110 insects were collected, from which 61.8% were from theTrigona spinipesspecies. However, in the pollination tests the fruit set was not observation, indicating that vegetative propagation is the main type of reproduction used by this population. This may be related to a mechanism of sporophytic self-incompatibility, to chromosomal abnormalities during the formation of pollen, to weather conditions, and to the low genetic variability at the study site.

Floral biology of cacauhy (Theobroma speciosum - Malvaceae)

In the present work, cacauhy's (Theobroma speciosum) floral biology was studied. Flower buds split their sepals at 14h reaching its maximum at 22h, but all flowers were fully opened at 6:00 h of the following morning. Stigmatic branches showed exudates, reaching maximum between 6:00 h and 10:00 h at the same day. Ligules and petal hoods were the floral parts with highest intensity of odour. Flowers were receptive along all the morning and noon of the anthesis day. Approximately 65 percent of the flowers were naturally pollinated, but only 0.85 percent of them set a fruit. Abscission occurred on its higher frequency at 6:00 h of the second day after anthesis. Controlled pollinations showed that cacauhy was self-incompatible species.

Neste trabalho foi estudada a biologia floral do cacaui (Theobroma speciosum). Os botões florais romperam a suas sépalas às 14h com a maior freqüência às 22h, estando completamente abertas às 6 h da manhã seguinte. Os braços estigmáticos apresentaram exsudato, com o nível máximo entre 06 e 10 horas da manhã do mesmo dia. As lígulas mais as cógulas foram as partes florais com odor mais intenso. As flores estavam receptivas durante toda a manhã e à tarde do dia da antese. Aproximadamente 65 por cento das flores foram naturalmente polinizadas, mas somente 0,85 por cento formou fruto. A abscisão ocorreu com maior frequência às 6 h do segundo dia após a antese. Polinizações controladas mostraram que o cacauí é uma espécie auto-incompatível.

Aspectos da biologia reprodutiva de Jatropha curcas L / Reproductive biology aspects of Jatropha curcas L

O conhecimento da estrutura floral e da biologia reprodutiva numa cultura é básico para que o melhorista desenvolva técnicas de castração e polinização adequadas. Objetivando obter dados de biologia reprodutiva de pinhão manso, inflorescências emasculadas, foram observadas sem isolamento (controle positivo) e isoladas com tecido "nylon" tipo voal para posterior realização dos tratamentos de geitonogamia e xenogamia após a antese. Os tratamentos consistiram de controle positivo (flores não isoladas), e a partir das flores isoladas foram obtidos os demais tratamentos: controle negativo (sem polinização); xenogamia (receberam pólen de outra planta); geitonogamia 1 (receberam pólen da mesma inflorescência); geitonogamia 2 (receberam pólen de outra inflorescência da mesma planta). Os resultados indicam que a espécie não apresenta problemas de autoincompatibilidade, sendo os índices de fecundação bastante elevados e indiferentes estatisticamente em todos os tratamentos, com valores acima de 80 por cento, exceto para o controle negativo em que as inflorescências foram isoladas e não polinizadas, resultando em ausência de fecundação e de frutos. Esse último resultado mostra a importância da visitação de insetos para a obtenção de sucesso no processo reprodutivo da espécie. As flores masculinas, doadoras de pólen, abrem no período da manhã, assim como as femininas. Sendo assim, embora haja visitação de insetos durante todo o dia, o processo de polinização ocorre no período matutino, em razão da quase total ausência de pólen no período vespertino.

The knowledge of the floral structure and reproductive biology are basic to a more successful for the development of techniques of castration and pollination in plant species. Aiming to obtain data about reproductive biology of physyc nut, free and enclosed inflorescences were observed without isolation (positive control) and isolation with nylon for posterior treatment of geitonogamy and xenogamy. So, treatments were positive control (free or unbagged inflorescences), and all other treatments obtained from isolated immature inflorescences enclosed within of fine nylon bags: negative control (without pollination), xenogamy (receiving pollen from another plant); geitonogamy 1 (received pollen from the same inflorescence), geitonogamy 2 (received pollen from another inflorescence of the same plant). The results indicate that the species does not present problems of self-incompatibility resulting in high fertilization and statistically indifferent in all treatments, presenting values above 80 percent, except for negative control in which the inflorescences were isolated and not pollinated resulting in lack of fertilization and fruit development. These results show the importance insects for success in the reproductive process of this species. The male flowers, pollen donors, opened in the morning, just like the female ones. Thus, although there is visitation of insects during all the day, the process of pollination occurs in the morning, and almost total absence of pollen was observed after noon.

The Progress on The Ubiquitin 26S Proteasome Pathway in Plants / 中国生物工程杂志

Selective protein degradation by the ubiquitin 26S proteasome pathway has emerged as a key regulatory mechanism in a wide variety of cellular processes.The ubiquitin/26S proteosome pathway mainly consists of ubiquitin activating enzyme(E1),ubiquitin conjugating enzyme(E2),ubiquitin protein ligase(E3),and 26S proteasome.In an ATP-dependent reaction,uibquitin(Ub) is conjugated to E1,the activated Ub is then transferred to an E2.Finally,the Ub-E2 intermediate delivers the Ub to the target protein by E3 recognition.Polyubiquinated proteins are eventually degraded by the 26S proteasome.In plants,regulated protein degradation by /26S proteasome pathway contributes significantly to development by affecting a wide range of progress,including hormone signaling,photomorphogenesis,self-incompatibility and cell cycle.The recent progress towards understanding the role of the Ub/26S proteasome pathway during plant development was reviewed.