| To explore the chestnut sugar components in the critical period,In this study,Yanshan chestnut ’Dabanhong’,’Yanbao’,’Yanlong’,“Funing12”,“Funing8”and“Qinglongjuli”were used as research materials to analyze the variation characteristics and correlation of sugar components,content and related nutritional indexes during the critical period of soluble sugar conversion.The purpose of this study is to provide reference for the evaluation of chestnut resources and sugar quality control of chestnut resources.After a comprehensive analysis,the following conclusions are drawn:1.With the increase of maturity,the chestnut buds of the six Yanshan chestnuts gradually changed from emerald green to yellowish green,the volume gradually increased,the spines increased,the yellow deepened,and the chestnut bud cracked.Chestnut nuts gradually change from milky white to turquoise,then to brown when mature,the skin becomes hard,the nuts continue to increase.Chestnut gradually changed from milky white to yellow white,size becomes bigger and chestnut becomes yellow.In the storage stage,the opening of the chestnut bud gradually expands,and the yellow gradually deepens.With the extension of the storage period,the chestnut bud becomes lighter due to the water loss,and its volume becomes smaller.In the later period of storage,the nut brown became significantly lighter and smaller.In the early stage of chestnut storage,there was no obvious change,but in the later stage,the volume became smaller and the weight became lighter.2.A total of 24 sugar components were detected in the mature fruits of the six Yanshan chestnut varieties(lines),among which the main sugar components accounted for 98%-99% of the detected sugar.The main sugar components were Sucrose,Glucose,D-fructose,Maltose,Inositol,Raffinose and D-galactose.In different varieties(lines),the structure of sugar components is basically the same,but there are some differences in the proportion.Among them,sucrose content is the highest,with a distribution range of 64.71-91.11%,with an average proportion of82.17%,followed by maltose content distribution range of 3.36%-17.49%,with an average proportion of 8.60%,and monosaccharides composed of inositol and glucose,with a sugar content of 1.97%-4.14%.The contents of D-galactose,D-fructose and Raffinose were relatively low,with an average proportion of 0.52%,0.42% and0.77%.3.Measurement of fruit sugar components at 75,85,95 and 105DAF(days after flowering),and 10,20,30 and 40LTS:From 75 DAFto 95DAF,the sucrose content in chestnut fruit showed a decreasing trend,and the fruit content began to rise after reaching the lowest point in ten days before ripening.As the highest amount of sugar in the chestnut fruit,the Sucrose content increased significantly through storage.The content of Raffinose,Inositol,Glucose and D-fructose in fruit all decreased significantly 75DAF-85 DAF.It was basically determined that this stage was the critical period for the consumption of these four sugar components.After that,except for raffinose and D-fructose,the content of the other two sugar components remained at a low level.Raffinose increased significantly in 95DAF-10 LTS and 30LTS-40 LTS,and these two stages were judged to be the critical period for Raffinose accumulation.While D-fructose increased slightly by 10LTS-30 LTS.Through storage,both Raffinose and D-fructose content increased in chestnut.Maltose and D-galactose content accumulated significantly one month before fruit ripening,and were rapidly decreased and maintained at low levels after entering the storage stage.The biochemical sweetness is completely consistent with the change law of sucrose content,which fully reflects the important role of Sucrose.Among the other five varieties(lines),D-fructose and Glucose were all positively correlated with water content.Similarly,the soluble sugars also showed a significant positive correlation with sucrose.In ‘Yanlong’‘Yanbao’and“Funing8”,Inositol,D-fructose,Glucose and protein content showed a significant positive correlation.4.With the principal component analysis,the quality of six chestnut varieties(lines)was found that the evaluation results of nutritional index and sugar component were not completely consistent.Among them,the nuts of‘Yanbao’and‘Yanlong’had better nut quality when they were ripe,and ranked among the top ten in the two evaluation methods.The sugar quality of the six chestnut varieties(lines)was optimal when the fruit was just ripe.However,different chestnut varieties(lines)have the same time to achieve the best nutritional quality.In conclusion,the main sugar components in the mature chestnut fruit were sucrose,glucose,D-fructose,maltose,inositol,raffinose,and D-galactose.In different varieties(lines),the structure of sugar components is basically the same,but there are some differences in the proportion.Among them,sucrose had the highest content,followed by maltose,and monosaccharides composed of inositol and glucose,including D-galactose,D-fructose and raffinose.In the developing period,the sucrose content of chestnut fruit showed a decreasing trend,and began to rise after reaching the lowest point before ten days of maturity.In the storage period,the sucrose content increased significantly.The content of raffinose,inositol,glucose and D-fructose decreased significantly 75DAF-85 DAF,except for the content of raffinose and D-fructose.raffinose showed a significant increase in 95DAF-10 DAFand 30LTS-40 LTS,while D-fructose increased slightly by 10LTS-30 LTS.Raffinose and D-fructose contents increased in chestnut after storage.Maltose and D-galactose content accumulated significantly one month before fruit ripening,and were rapidly decreased and maintained at low levels in the storage stage.Different chestnut varieties(lines)were evaluated according to the nutritional indexes and sugar components,and the results were not completely consistent.Among them,the nuts of‘Yanbao’and ‘Yanlong’ were of good quality when they first matured,and ranked among the top ten in the two evaluation methods.The sugar quality of the six chestnut varieties(lines)was optimal when the fruit was just ripe.From the physiological level analysis of the Chinese chestnut varieties(lines)fruit in sugar component transformation period change rule,compare different varieties(lines)sugar component difference,help to understand its genetic stability and breeding potential,to explore,utilization,innovative germplasm resources and realize artificial regulation of fruit sugar content has important guiding significance. |
PDF Full Text Request