| Selenium is an essential trace element in the human body.It has a broad development prospect by applying selenium to plants,increasing the selenium content of plants,and improving the selenium deficiency status of human bodies.‘Red General’apple is a strong red-type bud change of early-maturing Fuji.It is an excellent early-maturing variety that is currently popularized.At present,reports on the effects of selenium on the quality and storage characteristics of‘Red General’apple have not been reported.In order to study the effects of different selenium application methods and concentrations on the quality and storage characteristics of‘Red General’apple,this experiment used‘Red General’apple as experimental material,using leaf spray selenium and soil selenium to set 25 mg/L,50 mg/L,100mg/L,150 mg/L four different concentrations of sodium selenite solution were applied once,twice,three times in different growth periods,and the selenium was used to control photosynthesis of‘Red General’apple leaves.The effects of fruit quality and fruit storage characteristics provide a theoretical basis for the production and storage of selenium-rich‘Red General’apples.This experiment draws the following conclusions:1.Foliar application and soil selenium application were all treated with 150mg/L three selenium treatments to significantly increase the chlorophyll content of‘Red General’apple leaves,which were 86.43%and 37.96%higher than the control respectively.2.Both selenium application methods can increase the photosynthesis rate,stomatal conductance and transpiration rate of the leaves.Foliar application and soil selenium treatment were the most significant effects of selenium treatment at 150mg/L three times and 100 mg/L three times.However,selenium application reduced the intercellular CO2 concentration of the leaves,and the effect of inhibiting the intercellular CO2 concentration at 150 mg/L was the most obvious.3.Selenium application can increase the single fruit weight and horizontal and vertical diameter of the‘Red General’apple.When the leaf surface is sprayed with150 mg/L twice,the single fruit has the largest mass of 349.23 g,and the maximum vertical and vertical diameter is 150 mg/L,increased by 7.05%and 17.52%respectively compared with the control.The application of different concentrations of sodium selenite in the soil had no significant effect on the appearance quality of the‘Red General’apple.4.Foliar application of sodium selenite at a suitable concentration can effectively improve the intrinsic quality of‘Red General’apples,increase the selenium content,soluble solids content,soluble sugar content and sugar-to-acid ratio of the fruit,and the intrinsic quality of the fruit at 150 mg/L.Preferably,the amount of selenium in the fruit is 3.51 mg/kg,the content of soluble solid is 13.73%,the ratio of sugar to acid is up to 78.68%,and the content of titratable acid is the lowest,which has no significant effect on Vc content.Selenium application in soil had no significant effect on the soluble solids and titratable acid of‘Red General’apple.The soluble sugar content was the highest at 150 mg/L for three times,which was 10.48%.The Vc content increased significantly compared with the control,and the highest content was 50mg/L three times,which was increased by 666%compared with the control.5.The changes of selenium and selenium concentrations in different ways on storage hardness and related enzymes were determined.The results showed that the fruit hardness of different treatments decreased with the increase of storage time.Compared with the control,the increase of exogenous selenium can significantly reduce the hardness of‘Red General’apple during storage,and the higher the concentration,the more significant the effect on hardness.The hardness of the soil is the lowest when the concentration of selenium is 100 mg/L,which is 6.13 kg/cm2 was10.93%lower than the control.The content of pectin in the fruit of‘Red General’apple was decreasing continuously during storage.The trend of change was similar to that of fruit hardness.The pectin content after selenium treatment was significantly lower than that of the control.With the prolongation of storage time,the activity of PE,PG and CX related to fruit hardness related to different selenium treatments showed an upward trend.The activity of these three enzymes was the highest at 150mg/L.6.Different selenium treatments increased the activity of SOD,POD and CAT during fruit storage.At the 35th day of storage,SOD and POD activities were highest when foliar application of 150 mg/L sodium selenite solution was performed,which increased by 28.4%and 70.13%respectively compared with the control.The CAT activity was highest when the 150 mg/L sodium selenite solution was sprayed twice on the 28th day of storage,which was 94.06%higher than the control.Selenium application in soil was consistent with foliar spray selenium.SOD and POD activities were also highest when 150 mg/L sodium selenite solution was applied for 35 days,which was higher than that of control 31.2%and 52.46%,respectively.The CAT activity was highest when applied twice with 100 mg/L sodium selenite solution on the 28th day of storage,which was 109.88%higher than the control. |
