| The technology of bagging originated in Japan.It is mainly applied in apples to improve the color quality of fruit.Meanwhile,bagging can improve surface smooth finish of fruit and reduce disease.As a newly developed yellow-green variety of late ripening,‘Ruixue’has great differences in its cultivation measures from many red varieties.In the production,it was found that the bagging time and the selection of fruit bags were not suitable,which was easy to cause the peel browning.In order to explore the suitable bagging time and the color of fruit bag for‘Ruixue’apple,a total of 7 bagging times were set from 50to 115 days after full bloom（DAFB）to compare the external quality indexes such as peel browning,smoothness,coloring,fruit spot and chlorophyll content,and internal quality indexes including fruit soluble solid,firmness,total phenols,flavonoids and volatile aroma substances.The best bagging time of‘Ruixue’was evaluated by the method of membership function.At 70 DAFB,the fruits were bagged with different colors such as red,orange,yellow,green,blue,indigo,purple and white and the spectrograph was used to measure the transmitted light spectrum,and correlation analysis was used to investigate the relationship between light quality and fruit quality in the fruit bags.In this study,we have provided theoretical basis and technical support for the production of high quality‘Ruixue’apple in order to select the best bagging time and the best fruit bag color,the main research results are as follows:1.Effects of different bagging time on fruit quality of‘Ruixue’appleThe browning index and rate of 7 bagging time treatments in 2021 were shown that the bagging time affects fruit external quality,delaying the bagging time could reduce the occurrence of peel browning of‘Ruixue’.Compared with the ordinary double-layer tricolor bag,the browning index of Ruixue of special bag was reduced by 22.95%,but the delay of the bagging time would increase the fruit spot index and reduce the smoothness.The chlorophyll content of Ruixue of special bags generally increased first and then decreased,and the chlorophyll content of Ruixue of special bags at 90 DAFB was the highest,which was 26.02 mg·kg-1.The bagging time affected the internal quality of fruits,and delayed the bagging time could increase the contents of soluble solids,total phenols and flavonoids of fruits.And bagging with ordinary double-layer tricolor bag and Ruixue of special bag reached the highest at 115 DAFB.The results showed that the fruit quality of Ruixue of special bags at 90 DAFB was the best in two years by using the method of membership function.2.Effects of different color of fruit bag on fruit quality of‘Ruixue’appleThe difference in the color of the fruit bags changed the composition of the light quality and had a positive correlation between the light quality and fruit bags.Compared with white bag control,the transmittance of purple in purple bag were the highest,which were 1.15times than that in white bag;meanwhile,the transmittance of red in red bag were the highest（1.13 times）.Compared with other color fruit bags,some indicators of purple fruit bags were significantly improved,such as chlorophyll(54.82 mg·kg-1),total phenolic(1.325 mg·g-1),and total flavonoid content of fruits(1.361 mg·g-1).Under different light quality environments,there were significant differences in fruit firmness,and the fruit firmness with the red fruit bag was significantly lower,which was 16.1%lower than white bag control.In addition,other internal quality showed that the indigo fruit bags significantly improved the flavor of the fruits,which mainly improved soluble solids,sugar components and sweetness value.The detection of aroma compounds showed that the blue fruit bag significantly increased the total amount of fruit aroma compounds,which was significantly increased by2.89 times Based on the above indicators,a correlation analysis between light quality and various quality indicators was conducted,and found that there was a close correlation between fruit external quality and light quality.The correlation coefficients between the purple/indigo,orange,and purple/blue values and the L*,a*,and b*values of the peel were0.901,0.810,and 0.854,respectively.The internal quality of fruit,such as chlorophyll,total flavonoid,total phenolic and total aroma compounds,were most closely related to blue light,and the correlation coefficients of them with blue light were 0.947,0.822,0.851 and 0.757,respectively.During the production process,at about 90 DAFB,the use of special bags with higher violet and blue light transmittance can significantly improve fruit quality. |
PDF Full Text Request