蝴蝶花花器结构和开花授粉生物学特性

Flower Structure and Biological Characteristics of Flowering and Pollination in Iris japonica Thunb.

通过田间观察,运用杂交指数、花粉及柱头活力、花粉/胚珠比、坐果率等指标,对蝴蝶花（Iris japonica Thunb.）人工种群的花部特征、开花动态及授粉特性等进行研究。在人工栽培条件下,蝴蝶花2-4月份开花,群体花期62d,单株花期9～28d,单花花期36～48h。雄蕊短于花柱,花药与柱头相差0.32cm,在花朵开放的整个过程中雌、雄蕊的相对位置始终不变。杂交指数OCI=4,P/O值为275.68,结合坐果率结果,判断其繁育系统属于异交,部分自交亲和,需要传粉者。特殊的花部结构可能是蝴蝶花结实率较低的原因。

A field investigation was conducted on the floral syndrome and pollination characteristics of Iris japonica Thunb. in artificial populations by continuous observation, out-crossing index, pollen-ovule ratio and fruit-set rat. The main results are as follows： Under artificial culture conditions, the population come into bloom from Febrary to April and the flowering span among populations is 62 days. The flowering span for a plant is 9 -28 days. The life span of one single flower was approximately 36 -48 hours. The stamen was close to the lateral side of the petaloid style and 0. 32 cm shorter than the style, and the relative position between the stamen and style was always unchanged in the whole tlowering process. The out-crossing index was 4, P/O was about 275.68, combined with the result of the bagging and artificial pollination experiment, the breeding system of those species was given priority to out-crossing, part self-compatibility, insects pollinatordependent. The special floral structure may be the reasons that those species have a low setting percentage.