‘哈斯’油梨花芽分化和开花过程观察

Observation on Flower Bud Differentiation and Flowering Process of ’Hass’ Avocado(Persea americana)

以‘哈斯’油梨(Persea americana Mill.‘Hass’)为材料,利用石蜡切片技术和直接观察法研究其花芽分化和开花过程。结果表明:在广州市地区,‘哈斯’油梨末级梢顶芽的花芽分化始于12月下旬,主要划分为花序分化、花被分化、雄蕊分化和雌蕊分化4个阶段;单个花序分化自上而下进行,顶端花最先完成分化。每朵花36 h内开闭两次,存在雌雄蕊同花异熟现象,第1次开花时间为当日6:30—10:30,闭合为10:30—12:30,此阶段雌蕊成熟,具有受精能力;第2次开花时间为次日9:30—14:30,闭合为14:30—16:40,此阶段花丝伸长,雄蕊成熟,向外散粉;两次开花时间有部分重合。生产上可根据此特性来配置授粉树品种。

The flower bud differentiation and the flowering process of‘Hass’avocado were studied by means of the paraffin section technique and the direct observation method.The results showed that,in Guangzhou,the flower bud differentiation of the terminal shoot of‘Hass’avocado began in mid-late December,which was divided into four stages:inflorescence differentiation,perianth differentiation,stamen differentiation and pistil differentiation.Individual inflorescences differentiated from top to bottom,and apical flowers were the first to complete differentiation.The single flower of‘Haas’avocado has the characteristic of twice flowering,which opens and closes twice within 36 hours,and there is the isomorphism of pistil and stamen.The first flowering time was 6:30–10:30 and 10:30–12:30 was closed.The pistil matured at this stage and had the ability of pollination.The second flowering time was 9:30–14:30 at the next day,14:30–16:40 was closed.At this stage,the filaments elongated,stamens matured and pollinated outward.There is a partial overlap between the two flowering times,and pollination tree varieties can be configured on the basis of the two times of flowering.