Effects Of CaCl₂ And Heat Shock On The Fruit Of Hybrid Citrus Cultivar-Shiranui Tangor In The Low Temperature Stress

'Cultivar-Shiranui Tangor' had good quality,but it was vulnerable of the frost on the December to February because it maturity in the winter of the cold season on the February to March and the fruit had to on the trees in Winter.In this study,used the materials in the adult citrus orchards of the Heshan Town Pujiang Sichuan.Discussion the variety of the enzyme alive and HSP as well as the effect and mechanism of the resist freeze after deal with the different concentrations of CaCl₂ and different times of the 38℃heat treatment on the fruit in low-temperature -5℃.In low-temperature -5℃under Stress,the experimental results showed that:(1) 10mmol·L^-1 CaCl₂ deal with the membrane permeability of peel and the MDA for the lowest;After 9h of 38℃hot air heat-shock treatment,the membrane permeability of skin and the MDA were reduced of best treatment;used of the CaCl₂ and heat shock at the same time,the effect was better than treatment alone,with 10 mmol·L^-1 CaCl₂ and heat shock 9h,reduce the membrane permeability and the MDA of the best.(2) Different concentrations CaCl₂ of the soluble protein content had increased effect.The soluble protein content higher than the handling of without CaCl₂.In 38℃heat shock treatment,the protein content was also marked higher than those without heat shock of the treatment;10 mmol·L^-1CaCl₂ and heat shock 9h at the same time increase the soluble protein content of the effect of marked higher than that of other treatment.(3) Under the treatment of the 100 mmol·L^-1CaCl₂,soluble sugar content and SOD activity were marked higher than other treatment;Heat shock after 9h soluble sugar content and SOD activity were the largest;100 mmol·L^-1 CaCl₂ and 9 h heat shock at the same time deal with the peel and pulp soluble sugar content and SOD activity higher than that of other treatment.(4) POD activity take on at first increased to reduce and then tended to increase along with increase of the concentration of CaCl₂.POD activity than other treatment under the 100 mmol·L^-1CaCl;At the same time use,100 mmol·L^-1CaCl₂ and 9h heat shock of the POD vitality enhance of the best results.(5) CAT activity taked on increased to reduce along with increase of the concentration of CaCl₂;9h heat shock after the CAT activity showed maximum; 10mmol·L^-1 CaCl₂ and 9h heat shock at the same time deal with the CAT vitality of the highest.(6) With different concentrations of CaCl₂ spraying fruit processing induced by HSP for the increase was not very obvious changes,failed to induce the new formation of HSP,also failed to induce HSP increase in the original; 9h of heat shock,although not can induce a new HSP,but effective with the induction of the effect of the increase in protein and was all the time induced by HSP increase the most,the deepest color bands;100mmol·L^-1CaCl₂ and heat stimulated 9h at the same time,increase the original amount of HSP was the largest.