“云新高原”核桃果实生长发育规律研究

Growth Rules of Walnut Cultivar 'Yunxin Gaoyuan'

以"云新高原"核桃为试验材料,定期观测果实生长纵径、横径、侧径的生长量,采用logistic模型,二次多项式,三次多项式分别对核桃果实三径进行了曲线拟合。结果表明,"云新高原"核桃果实三径累积生长量随生长时间的动态变化呈慢—快—慢的"S"型曲线,累积生长量始终保持纵径>横径>侧径的生长特点;3种模型拟合果实三径的生长过程,用三次多项式对"云新高原"的纵径拟合的精度效果优于Logistic模型和二次多项式,而果实的横径和侧径则用Logistic模型拟合优于二次多项式和三次多项式。结合果实三径相对生长速率与生长变化曲线可将核桃生长过程分为生长初期,快速生长期,稳定生长期,为不同阶段核桃采用不同的栽培管理措施提供了参考依据。

A walnut cultivar‘Yunxin Gaoyuan＇ was used as material to study its growth rules. The growth parameters of the walnut fruit were measured regularly, such as the increment of longitudinal diameter, transverse diameter and side diameter. The growth dynamic measurements were fitted by Logistic model, quadratic polynomial and cubic polynomial. The dynamic variations of the accumulative growth of three di- ameters showed ＂S＂ pattern as slow-fast-slow,and the cumulative increment was in the order of longitudi- nal diameter〉 transverse diameter〉side diameter. The fruit longitudinal diameter cloud be described bet- ter by cubic polynomial than by Logistic Model and quadratic polynomial, and the fruit transverse diameter and side diameter cloud be described better by Logistic Model than by quadratic polynomial and cubic poly- nomial. Considering both the changes of relative growth rates and the curves of three diameter of walnut fruit, the growth process of walnut could be divided into three periods： initial-growth period, fast-growth period,and stable-growth period,which provided a reference for determining the different periods of walnut cultivation and management measures.