树形对适收期黄花梨糖度VIS/NIR光谱检测的影响研究

Effect of Tree Shapes on Prediction of Sugar Content of Huanghua Pear in Harvest Time Using Visible/Near Infrared Spectroscopy

针对树体的光通透性影响果实糖分的积累,不同树形的果实品质存在差异的问题,研究了树形对适收期黄花梨糖度可见/近红外光谱检测模型的影响。采集了适收期前后6个批次、不同树形(开心形和棚架形)的黄花梨果实480个进行实验,两类树形果实糖度差异显著(p<0.05),采用同一树形黄花梨建立的模型预测均方根误差(RMSEP)分别为0.69°Brix、0.64°Brix,相对分析误差RPD分别为2.08、1.97;单一树形全部样品建立的模型对不同树形样品的RMSEP分别为1.31°Brix、1.07°Brix,RPD分别为1.14、1.36;2类树形联合模型RMSEP为0.59°Brix,RPD为2.38。结果表明,树形对适收期黄花梨糖度预测模型的精度和稳健性均有较大影响,对进一步研究近红外光谱技术在田间水果采收期品质及最佳采收期检测的应用有一定的参考价值。

Light permeability of tree affects the accumulation of sugar in fruits,and there is a difference in quality of fruit between different types of trees. The effect of tree shapes on prediction of sugar content of Huanghua pears in harvest time by visible / near infrared spectroscopy（ VIS / NIR） was evaluated.A total of 480 pears were picked from opening canopy trees and trellis-trained trees in six batches,there was significant difference in fruit sugar content between two types of fruit trees（ p〈 0. 05）. The root mean square error of prediction（ RMSEP） and residual prediction deviation（ the ratio of standard deviation to RMSEP,RPD） of models of single tree shape fruits for predicting similar fruits ranged from0. 69°Brix to 0. 64°Brix,and from 2. 08 to 1. 97,while for all fruits of different tree shapes,they ranged from 1. 31°Brix to 1. 07°Brix,and from 1. 14 to 1. 36,respectively. The RMSEP of the combined model was 0. 59°Brix,and RPD was 2. 38. The results showed that the model established by single tree shape fruits had poor performance,while a model established by using combined shapes fruits would obtain ideal robustness and good accuracy. The results would help to further utilize VIS / NIR to test quality of fruits in harvest time and predict the optimal harvest time.