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.

Study on Crossing Ability of Annual Chrysanthemum Genotypes.

The experiment comprised of six genotypes viz., NAC-01-10, NAC-02-10, NAC-03-10, NAC-04-10, NAC-05-10, NAC-06-10 selected for petal colour and number of layers of petals to estimate pollen viability, in-vitro pollen germination, stigma receptivity and crossed seed set percentage to find out the crossing ability of genotypes. The present experiment was laid out at the experimental field of Horticulture Section, College of Agriculture, Nagpur, during 2010-11. Pollen viability of six genotypes of annual chrysanthemum showed a range of 69.69% to 86.66% viability, Percentage of germination on the day of anthesis ranged from 22.72% (NAC-06-10) to 66.66% (NAC-01-10). First day pollen pollinated on first day stigma showed 100% stigma receptivity in all six genotypes and the crossed seed set ranged from 61.60% (NAC-04-10 × NAC-05-10) to 92.00% (NAC-01-10 × NAC-04-10) among direct crosses whereas, the percentage ranged from 42.00% (NAC-04-10 × NAC-02-10) to 90.00% (NAC-05-10 × NAC-01-10) among the reciprocal crosses. All the six genotypes are highly suitable for their use as parents in crossing program.

Propriedades do pólen e do estigma de Ocimum basilicum L. (cultivar Maria Bonita) para aumentar a eficiência de cruzamentos em programas de melhoramento / Ocimum basilicum L. (cultivar Maria Bonita) pollen and stigma properties to improve the efficiency of crossings in plant breeding programs

Ocimum basilicum, cv. Maria Bonita (Lamiaceae), conhecido como manjericão, é espécie que apresenta propriedades aromáticas, condimentares e medicinais, por ser rico emóleos essenciais. É muito usado nas indústrias farmacêuticas e de alimentos em geral. O objetivo deste trabalho foi estudar as propriedades do pólen e estigma do manjericão (cultivar Maria Bonita) identificando procedimentos simples que possam contribuir para programas de melhoramento. Para análise da disponibilidade, viabilidade do pólen e receptividade de estigma, botões florais foram coletados de hora em hora ao longo do dia, e lâminas eram montadas e coradas, para observação em microscópio óptico. Foi verificado que o manjericão apresenta antese diurna, assincrônica e com a maioria das flores se abrindo entre 10:00 e 11:00 horas. Quanto ao estudo do pólen foi verificado que a viabilidade manteve-se elevada ao longo do dia e a conservação por até 90 dias demonstrou bons níveis de viabilidade. O estigma apresentou receptividade desde a pré-antese até a pós-antese. Estas informações são relevantes para os melhoristas que desejam fazer seleção de genótipos ou hibridações em programas de melhoramento, contribuindo para aumentar o potencial da espécie que já se destaca como produtora de óleos essenciais.

Known as basil, Ocimum basilicum cv. Maria Bonita (Lamiaceae) is a species that presents aromatic, condimental and medicinal properties, since it is rich in essential oils. This species is largely used in pharmaceutical and food industries. The aim of this work was to study basil (cultivar Maria Bonita) pollen and stigma properties, identifying simple procedures that can contribute to plant breeding programs. To analyze pollen availability and viability, besides stigma receptivity, flower buds were collected at every hour throughout the day, and slides were mounted, stained and observed under an optical microscope. Basil presented diurnal asynchronous anthesis and most flowers opened between 10:00 and 11:00 a.m. As regards pollen analysis, viability was high throughout the day and its conservation until 90 days was good. Stigma presented receptivity from pre- to post-anthesis. These data are relevant to breeders who wish to select genotypes or hybridizations in plant breeding programs, contributing to improve the potential of this species, which already represents a producer of essential oils.