The Changes Of Aromatic Synthesis Of ’Aiganshui’ Pear During Fruit Development And The Effect Of Ethylene On The Aromatic Synthesis

The contents of aroma ethylene production and the activities of aroma-metabolizing were measured during the fruit development of’Aiganshui’pear. And the characteristics aroma, changes of aroma components and the activities of aroma-metabolizing key enzymes of aroma were studied.And explore how ethylene production effects ’Aiganshui’ characteristic aroma and the activities of aroma-metabolizing key enzymes after’Aiganshui’trees were sprayed at different concentrations of ethephon.The results showed that:(1) Hexanal,2-Hexenal,Ethyl hexanoate, ethyl benzoate, ethyl butyrate, ethyl butyrate, ethyl valerate,ethyl caprylate, Butyric acid-2-ethyl propyl ester, nonadecane were the characteristic aroma components of’Aiganshui’pear.(2) the main aroma components were esters, aldehydes and alcohols.Among of them,the change regularity of percentage content of esters was increased during fruit development, they were increased from 0.41% to 57.05%; aldehydes were increased-decreased during fruit development and the maximum was 31.86%;but the change regularity of percentage content of alcohols appeared like ’M’ during fruit development,the maximum was 18.28%.(3) Correlation analysis showed that a positive correlation was observed between the content of esters and aldehydes and the activity of LOX、HPL、ADH、AAT, while there was a negative correlation between the content of alcohols and the activity of LOX、ADH、AAT,the content of alcohols was positively relevant with HPL.It suggested that LOX, HPL, ADH, AAT are the key enzymes of the accumulations of esters and aldehydes,but LOX, ADH, AAT don’t benefit for the accumulation of alcohols. It Showed that,LOX,HPL,ADH,AAT promotes the synthesis of esters, aldehydes, LOX, HPL, AAT inhibited the synthesis of alcohols.(4) Eeffet of ethephon on the ’Aiganshui’ fruit characteristic aroma and the activities of aroma-metabolizing key enzymes were tested. Application of ethephon was sprayed at the ripen fruit and concentrations were 0、100mg·L-1、150mg·L-1、200mg·L-11、 250 mg·L-1、300 mg·L-1. The result of total evaluation of fruit flavor showed that 200 mg·L-1 treated was the best,because the ’Aiganshui’ pear fruit not only kept aldehydes producting,but also accelerated esters.