Ethylene Transferase Activity And Gene Expression Of Aroma And Alcohol 1-MCP-treated Group

Kiwifruit is ethylene sensitive fruit, aroma is an important index of fruit quality, including esters are the most important aroma components of kiwifruit.1-MCP is an inhibitor of ethylene action, is often used as a preservative of kiwifruit, although the kiwifruit has obvious preservation effect.1-MCP has a significant effect on the preservation of kiwifruit, but inhibited the formation of volatile substances in fruit, especially the formation of esters, affected the eating quality. Alcohol acyltransferase (AAT) is the esters synthesized at the end of the key enzyme, at present, about the effect of ethylene on AAT has not been reported. In order to improve the eating quality of kiwi fruit, this paper attempts to solve the negative effects of1-MCP in kiwifruit storage. The fundamental purpose is to prolong the storage period of kiwifruit fruit at the same time, also can keep the fruit best flavor quality, achieve the purpose satisfy both sides, which can provide the theoretical basis for the practical production and sales guidance. This paper attempts to study the0,0.25,0.5μL·L-11-MCP treatments of’Hayward’kiwifruit in cold (0±0.5℃) on the expression of AAT activity and AAT gene change, fruit aroma substances during the storage. The results were as follows:1. The different harvest time kiwifruit ATT enzyme activity change was researched. As the nature of the fruit mature, ATT enzyme activity increased. The first four periods in kiwifruit, AAT enzyme activity showed an increasing trend in the shelf-life period, the activity of AAT fifth and sixth time of the kiwifruit in the first increase in shelf period and then decreased, reached a maximum value at6d and3d respectively,36.8mU/mg and38.9mU/mg. In the shelf period, along with the fruit ripening, AAT enzyme activity gradually increased then decreased. The sooner fruits were harvested, the later AAT enzyme activity peak appeared.2. The activity of AAT enzyme in fruit treated with1-MCP decreased significantly, AT1, AT2, AT17gene expression decreased obviously. Reprocessing of1-MCP treated fruit with exogenous ethylene, the results showed that the fruit ester aroma type and quantity were increased to some extent, enhanced the activity of AAT, promote AT1, AT2, AT17gene expression, that these three genes were related with kiwifruit volatile ester synthesis. And AT15, AT18gene showed the opposite effect, they might be related to the growth of ester synthesis genes. According to the changes of the expression of AAT enzyme activity and gene that ethylene treatment does have a certain role in the recovery.3. Relative transcription of AAT gene was also affected by harvest time, change trend more obvious is the ATI, AT2, AT17three gene, the first four periods increased during shelf period, fifth times and sixth times after harvest decreases in shelf period, which can be known more, harvest period first, the relative transcription of AAT gene in the peak of the late, the harvest more late peak earlier. Analysis of transcription of these three genes may be regulated by endogenous ethylene production during fruit ripening, further speculated that produced it may participate in the aroma of fruit during ripening. The relative transcription of AT15and AT18trend is not obvious. Visible in fruit mature period, AT1, AT2, AT17played a key role, is related to fruit ripening genes.4.1-MCP treatment had a certain influence the composition and quantity of aroma components of kiwifruit, which were detected in16kinds of ester compounds. different storage period of ester composition and content are different. With0.5μL·L-11-MCP treatment had the most obvious effect, in30d and75d, treatment group than in the control group were reduced by41.7%and45.4%, the lowest in75d. The results show that the endogenous ethylene effect is the same with the prior experimental results, proving once again that these3genes in ester synthesis process plays a leading role in the. That ethylene can restore kiwi in a certain extent, aroma, solid theoretical basis for application of production in the future.