The Effect Of Bagging On The Fruit Quality And Expression Of Myb Transcription Factor Genes In Malus Pumila Mill

The experiment was carried on in red Fuji apple,which 3 kinds of fruit bags was used in Xuzhou Jiangsu fruit areas from 2007 to 2008. Meanwhile,the changes of chlorophyll, sugar and acid content were measured after bagging; chlorophyll, sugar and PAL activity were measured after debagging; a gene MYB10d was cloned,and it was analyzed by Real Time Quantitative PCR. The aim was to select better fruit bag for Xuzhou fruit area and research the inherent physiology and physics mechanism that fruit coloration after debagging,which hoped perfecting the bagging technology and guiding the apple production.The results indicated as follows:1 The double paper bag clearly improved the fruit outside quality,enhanced the content of anthocyanin,decreased the content of chlorophyll,accelerated fruit coloring;it also decreased the fruit rust index,increased the clearness index;2 The chlorophyll content in bagging apple fruit skin was lower than control.Among them,Chl.a. was lowered most and it was parallel with total chlorophyll content.The capacity of carrotenoid was lowered little,which is more advantageous to the fruit coloring.The content of anthocyanin was notably lower than control during the purity.After bags removed,it was rapidly increased and surpassed the control after 6 days of bags removed.When harvesting,the anthocyanin content of bagging fruits surpassed control more than one times.3 The fruit bagging influenced the content of the carbohydrate.The experiment indicated that the titratable acid is notably lowered in red Fuji apple after bagging.It was lowered in the content of various soluble sugar and reducing sugar to some extent,there is the same change trend between bagging and control.4 Chlorophyll and carotenoid were inereased after bags removed,but were lower than that of control. Debagging increased PAL activity first,then decreased it. PAL activity was higher than that of control after 4 days of bags removed,and it reached highest after 6 days of bags removed.But after 8 days of bags removed, PAL activity was higher than that when bags removed;5 Debagging increased content of total soluble sugar, fructose and glucose.Sucrose content increased immediately after 4 days of bags removed,then it decreased.But after 8 days of bags removed, sucrose content was higher than that when bags removed;6 A gene MYB10d in'red Fuji'apple (Malus pumila Mill.) was cloned by rapid amplification of cDNA ends (RACE). By bio-informatics analysis,MYB10d gene was classified into MYB transcription factor class. The results of Real Time Quantitative PCR analysis of apples under debagging demonstrated that MYB10d gene expressed strongly after 2 days of. bags removed,then it decreased.MYB10d gene faintly expressed after 6 days of bags removed.7 The comprehensive results indicated that HengXin in ShanDong was the best in the three double paper bags,TianZhengin XuZhou was the worst.