Comparative Studies On Flowering Biology Of 5 Agapanthus Species

Agapanthus belongs to monocotydoneae, Asparagales, Its original species occurs in South Africa. It is a kind of herbaceous flower with watching ,officinal and other functions. We discuss the flowering biology character through the research of five species of Agapanthus (A. praecox ssp. orientalis 'Mt Thomas',A. praecox ssp. orientalis 'Weaver',A. praecox ssp. orientalis 'Big Blue',A. nutans,A. hybrid). All the experiments included in this thesis had been done under greenhouse conditions of Northeast Forestry University and the main conclusions are:1. Agapanthus blossoms two times a year under greenhouse conditions and the flowering span was March to July and September to December. Each species of Agapanthus had its own flower longevity. Except for 424/82, the curve of flowering process showed two major peaks. The values of relative flowering intensity mainly distributed between 60%～80%. The time of florescence overlay was short which elongate the whole flowering span of the species.2. The individual flower longevity was 3 to 5 days and the average was 4 days. Stigma surpassed the anthers after blossoming for two or three days and could accept the pollen when transparent droplets formed on the surface. During the flowering process of a single plant, there was no obvious flowering peak. The percentage of open flowers per day were between 10～20% after blossoming for ten to twenty-four days.3. Fertilization on flowers had significant influence on blossoming. The relative parameters were enhanced to some extent after fertilization. So we can conclude that fertilization enlarged and concentrated the number of opening plant.4. The best way to test the pollen vigor is vitro germination, Through the test we can get the optimum germination medium, in which the concentration of the sugar, B⁺ and Ca²⁺ are 5g/L, 0.05g/L and 0.1 g/L respectively.5. The pollen vigor of a single flower did not change essentially in the first four days. But the vigor gradually declined with time passed after the petal fell. All through this period, the stigma could be granted. The variability of pollen vigor represented a same trend basically.6. Four degree was the suitable temperature to store the pollen, and fifty percent of the pollen could maintain its vigor under this condition for one month in three species..7. Outcrossing index were 4～5. pollen-ovule ratio were 21314～28118. together with the seed setting ratio showed that the breeding system can be determined as outcrossing with partly self-compatible and needed pollinators during the pollination. 8. Anther wall of Agapanthus developed as monocotyledon type, glandular tapetum. Cytokinesis in the microsporocyte meiosis was of the continuous type. Microspore tetradswere symmetrical structure .Mature pollen grains were 2-celled.