绦柳雌株花芽分化

Floral Bud Differentiation in Female Salix matsudana f. pendula

绦柳是我国北方地区重要的园林绿化树种,但果实飞絮污染严重危害市民健康及公共安全。为了确定绦柳雌株花芽分化过程,推动飞絮控制技术的发展,采用石蜡切片法观察注射及未注射"抑花一号"的绦柳雌株花芽。结果表明,临沂地区绦柳雌花芽分化自5月21日开始,观察期间经历了花序原基分化期、小花原基分化期、雌蕊分化期3个时期;6月5日至7月10日进入成花决定,此时花芽呈绿色,长宽比无固定比例,剥开芽鳞后大量绒毛包被着花序,内部花序轴两侧苞片及小花原基突起基本全部形成,但尚未分化出雌蕊原基;结合物候期观测数据,初步明确在果实脱落期后的52 d左右进入成花决定,为抑制花芽分化、控制绦柳飞絮提供了科学依据。

Salix matsudana f. pendula is an important landscaping tree species in northern China,but the flying willow fuzz with severe pollution caused by female flower do harm to the health of citizen and public security. In order to find the mechanism of female flower bud differentiation of S. matsudana and promote the technologies of the flying willow fuzz control,paraffin section and No.1 of blossom restrainer（ BBR Ⅰ） injection were used to study the female flower bud differentiation process and characteristics. The female flower bud differentiation in Linyi started on May 21 and went through three phases in the observation which was inflorescence primordium differentiation,floret primordium differentiation and pistil differentiation.The floral determination started from June 5 to July 10 when the appearance was green and satiation with no fixed proportion length-width ratio while the inflorescence without bud scales was covered with pubescence and the bracts on both sides of internal inflorescence axis and the floret primordium formed basically,but the pistil primordium has not been differentiated yet. Combining phenological observation data,the floral determination started 52 d after the beginning of fruit abscission stage. The results would provide scientific basis for controlling the flying willow fuzz by inhabiting floral bud differentiation.