靖西大果山楂果实生长与果熟期果实营养动态分析

Fruit Growth and Dynamic Analysis on Fruit Nutrients at Fruit Ripening Period of Malus doumeri in Jingxi

为掌握靖西大果山楂(Malus doumeri)果实生长发育及其在果熟期的营养动态变化规律,以靖西大果山楂果实为材料,观测和划分生长周期,并对果熟期果实的营养成分(糖、总酚、总黄酮、三萜、氮、磷、钾、钙和镁)含量进行测定和分析。结果表明,靖西大果山楂果实生长可分为迅速生长期(3月中旬—6月中旬)、缓慢生长期(6月中旬—8月中旬)、熟前速长期(8月中旬—9月中旬)和采前缓慢生长期(9月中旬—10月中旬)4个时期。采用Linear、Logarithmic、Quadratic和Logistic模型对果重、纵径、横径和糖度进行拟合;R^(2)最高的方程均为Quadratic方程,决定系数均在0.930以上,拟合程度均较高。在果熟期,果实糖度及总酚和总黄酮含量均随生长时间增加而升高;三萜含量呈先升后降的趋势,在10月15日最高;常量营养元素含量均表现为钾>氮>钙>磷>镁。果实糖度、总酚含量和总黄酮含量间均呈极显著正相关,磷含量与钾含量呈显著负相关。果重和果实营养成分含量均在10月中旬较高,靖西大果山楂果实较佳采收期为10月中旬。

In order to grasp growth and development of Malus doumeri fruits in Jingxi and dynamic changes of fruit nutrients at fruit ripening period,taking M.doumeri fruits in Jingxi as materials,growth period was divided based on observation,and contents of fruit nutrients(sugar,total phenols,total flavonoids,triterpenes,nitrogen,phosphorus,potassium,calcium and magnesium)at fruit ripening period were measured and analyzed.Results showed that growth of M.doumeri fruits in Jingxi could be divided into four periods,including rapid growth period(from mid-March to mid-June),slow growth period(from mid-June to mid-August),rapid growth period before harvest(from mid-August to mid-September)and slow growth period before harvest(from mid-September to mid-October).Four models of Linear,Logarithmic,Quadratic and Logistic were used to fit fruit weight,vertical diameter,transverse diameter and sugar content respectively.All of Quadratic equations had the highest R^(2) with determination coefficients above 0.930,and fitting degrees were high.At fruit ripening period,contents of sugar,total phenols and total flavonoids increased with increase of growth time,and content of triterpenes increased firstly and then decreased with the highest on October 15th.Contents of macro nutrient elements followed order of potassium>nitrogen>calcium>phosphorus>magnesium.There were extremely significantly positive correlations among content of fruit sugar,total phenols and total flavonoids.Phosphorus content had significantly negative correlation with potassium content.Fruit weight and contents of fruit nutrients were higher in mid-October,so better harvest period of M.doumeri fruits in Jingxi was mid-October.