Acta Agriculturae Zhejiangensis ›› 2023, Vol. 35 ›› Issue (7): 1571-1581.DOI: 10.3969/j.issn.1004-1524.20221126

• Horticultural Science • Previous Articles     Next Articles

Flower bud formation and physiological biochemistry characteristics of Hongmeiren citrus hybrid in northern Zhejiang, China

WANG Zhihao1(), XI Xinyan1, WANG Li2, YANG Shuna1, GAO Zhiyuan1, YIN Yiming2, ZOU Hui3, JIA Huijuan1,*()   

  1. 1. College of Agriculture and Biotechnology, Zhejiang University, Hangzhou 310058, China
    2. Agricultural Technology Development Center of Huzhou, Huzhou 313000, Zhejiang, China
    3. Nanxun Shuanglin Deyuan Family Farm, Huzhou 313012, Zhejiang, China
  • Received:2022-08-02 Online:2023-07-25 Published:2023-08-17
  • Contact: JIA Huijuan

Abstract:

In order to reveal the flower bud differentiation rules and physiological biochemistry characteristics of different female branches of Hongmeiren citrus hybrid, and provide theoretical basis for the regulation of flowering and cultivation management. 6-year-old Hongmeiren citrus hybrid trees were used as materials. The frozen section technology was used to observe the morphological characteristics. In addition, endogenous hormones [abscisic acid (ABA), trans-zeatin-riboside (ZR), gibberellin (GA) and indole-3-acetic acid (IAA)] were determined by LC-MS and the leaves were dried for total carbon and nitrogen content determination. The morphological differentiation of flower buds was divided into 6 stages, including undifferentiated stage, initial differentiation stage, sepal differentiation stage, petal differentiation stage, stamen differentiation stage and pistil differentiation stage. The general trend was that the flower bud differentiation process of the front end shoots was faster than that of the middle and rear end shoots, and the proportion of flower bud in the pistil differentiation stage was higher. In three shoots, the carbon/nitrogen ratio(C/N), ABA/GA, ZR/GA, IAA/GA of autumn shoot in spring shoot and summer shoot and autumn shoot (SSA-AU) were higher than that of summer shoot in spring shoot and summer shoot and autumn shoot (SSA-SU) and spring shoot in spring shoot and summer shoot and autumn shoot (SSA-SP), while the C/N, ABA/GA, ZR/GA, IAA/GA of summer shoot in spring shoot and summer shoot (SS-SU) were higher than that of spring shoot in spring shoot and summer shoot (SS-SP), and the C/N, ABA/GA, ZR/GA, IAA/GA of autumn shoot in spring shoot and autumn shoot (SA-AU) were higher than that of spring shoot in spring shoot and autumn shoot (SA-SP). Before petal differentiation stage, GA content was high, ABA content, ZR content, ABA/GA and ZR/GA were all at low levels; after entering stamen differentiation stage and pistil differentiation stage, ABA content, ZR content, ABA/GA and ZR/GA all increased rapidly. Flower formation of the front end shoots was better, and the flower formation ability of middle and rear end shoots were weak, which was related to the difference in flower bud differentiation process, nutrient accumulation and endogenous hormone levels, and the hormones played a major regulatory role. The stamen differentiation stage (February 5 to February 20) was the critical period. Therefore, in the process of cultivation and management, special attention should be paid to the rational allocation of different types of female branches, the timing of topping and shoot release in summer and autumn, and trying to use hormones to regulate flower bud differentiation.

Key words: Hongmeiren, female branche, flower bud differentiation, endogenous hormone

CLC Number: