谷氨酸和TDZ对荔枝果皮着色及果实品质的影响

为提前或延迟果实的成熟,改善果实品质,以荔枝(Litchi chinensis Sonn.)早熟品种‘三月红’和‘水东’为试验材料,在盛花后50 d用谷氨酸(Glu)和TDZ(Thidiazuron)进行处理,研究Glu和TDZ对果皮着色和果实品质的影响。结果表明,Glu能促进果皮转红,500~1500 mg L-1范围内随浓度增加果皮红色面积加大,果皮的花青苷含量增加。1500 mg L-1Glu处理的‘三月红’‘、水东’果皮花青苷含量分别达到8.62 U g-1、11.53 U g-1,分别比对照高出1.33、1.25倍。同时,Glu处理能促进‘三月红’总糖的积累,但对两品种果实大小和质量的影响不大。TDZ显著迟滞果实着色,果实转红延后,果皮花青苷含量降低。5.0 mg L-1TDZ处理的‘三月红’‘、水东’果皮花青苷仅为1.23和3.4 U g-1,显著低于对照。TDZ处理两品种果实的可溶性固形物、总糖含量均下降,但果实大小和质量均增加。因此,Glu能促进荔枝果实转色成熟,TDZ则抑制果实转色。

Effects of Glutamic Acid and TDZ (Thidiazuron) on the Fruit Coloration and Quality of Litchi chinensis Sonn.

In order to accelerate or delay fruit ripening and improve fruit quality,two early mature litchi cultivars,Litchi chinensis Sonn.’Sanyuehong’ and ’Shuidong’,were treated with L-glutamic acid(Glu) and Thidiazuron(TDZ) at 50 days after blossom,the coloration and quality of fruits were determined.The results showed that Glu could promote fruits turning red.As the concentration of Glu(500–1500 mg L-1) increased,the red area and anthocyanin content in fruit pericarp increased.Treated with 1500 mg L-1 Glu,the anthocyanin contents in ’Sanyuehong’ and ’Shuidong’ pericarp were 8.62 U g-1 and 11.53 U g-1,respectively,which were 1.33 and 1.25 folds to control.Glu promoted total sugar accumulation in ’Sanyuehong’ fruits,but had little effects on fruit size and weight of two cultivars.Fruit coloration was retarded with TDZ treatment,and anthocyan content was decreased at harvest stage.After treated with 5.0 mg L-1 TDZ,anthocyanin contents in the ’Sanyuehong’ and ’Shuidong’ pericarp were 1.23 and 3.4 U g-1,respectively,which significantly lower than those in control.After treated with TDZ,the total soluble solid and sugar contents in fruits decreased,but the fruit size and weight increased.Therfore,litchi fruits sprayed with L-glutamic acid on the 50th day after blossom could accelerate maturation,but TDZ delayed.