四季蜜龙眼果实生长发育动态及其数学模型研究

Fruit growth and development of Sijimi longan and its mathematical model

【目的】研究反季节四季蜜龙眼果实生长发育动态,为制定高产、优质四季蜜龙眼栽培管理措施提供参考依据。【方法】跟踪测定反季节四季蜜龙眼发育期果实的纵径、大横径、小横径、单果重、果皮重、果肉重、种子重及可溶性固形物含量等指标,分别采用多项回归和求导方法建立四季蜜龙眼果实的生长发育数学模型和物质累积速度模型。【结果】反季节四季蜜龙眼果实生长发育需108 d,成熟阶段历时21 d。果径生长曲线前期上升较慢,中期上升较快;果肉重、果皮重、种子重和单果重在花后52 d开始快速增加;可溶性固形物含量在花后66～94 d快速增长,最高峰达25.1%。根据果实各指标数据建立的四季蜜龙眼果实生长发育数学模型,拟合出多项回归方程式,其中纵径、大横径、小横径、单果重及果肉重的拟合方程为二次方程,果皮重、种子重及可溶性固形物含量的拟合方程为三次方程,动态模型回归方程经F检验均达显著差异水平（P〈0.05）,决定系数R2均大于0.9800,达极显著差异水平（P〈0.01）;物质累积速度模型显示,果实纵径、大横径和小横径及单果重和果肉重5个指标的累积速度模型为一次直线方程,果皮重、种子重和可溶性固形物含量的累积速度模型为二次方程。【结论】四季蜜龙眼的生长发育动态及其数学模型可作为制定四季蜜龙眼高产、优质栽培管理措施的参考依据。

[Objective ]The present experiment was conducted to investigate fruit growth and development of off-season Sijimi longan, in order to provide a theoretical basis for taking appropriate measures to improve yield and quality of Sijimi longan fruits. [Method]Taking Sijimi longan as materials, the fruit growth and development indexes including longitudinal diameter, large transverse diameter, small transverse diameter, single fruit fresh weight, periearp weight, pulp weight, seed weight, soluble solids content were determined. The mathematical models of fruit growth and accumulative rate were established by polynomial regression and derivation calculus methods. [Result]The fruit growth of off-season Sijimi longan took 108 d, fruit mature stage lasted 21 d. The fruit diameter increased slowly at early stage, and rose fast to the peak at middle stage, then increase gently. The pulp weight, pericarp weight, seed weight and single fruit weight began to in- crease rapidly on 52 d after flowering, the soluble solids content began to increase rapidly in 66-94 d after flowering, then reached to the peak（25.1% ）. Based on to data about fruit indexes of Sijimi longan, the mathematical model of fruit growth was established, the multiple regression equations were obtained by fitting curve, including quadratic equations for longitudinal diameter, transverse diameter, fruit weight and pulp weight, cubic equations for pericarp weight, seed weight and soluble solids content. The results of F-test showed that, significant differences were found in regression equations of dynamic model（P〈0.05）, and the determination coefficients （R2） were above 0.9800, indicating that there existed ex- tremely significant difference （P〈0.01）. Furthermore, the models for accumulative rates of longitudinal diameter, trans- verse diameter, single fruit weight and pulp weight of Sijimi longan fruit were linear equations, the models for accumula- tive rates of pericarp weight, seed weight and soluble solids content were quadratic equations. [Conclusion]The dynamic and mathematical models for growth and development of Sijimi longan fruit can provide reference for formulating high-yield and high-quality cultivation and management measures.