亏缺灌溉对枸杞果实糖积累和蔗糖代谢相关酶活性的影响

Effects of deficit irrigation on accumulation of sugar and activity of sugar metabolism-related enzymes of Lycium barbarum L.

通过控制灌溉量将土壤水分控制在18.20%(T1),19.50%(T2),20.60%(T3),22.40%(T4),23.50%(T5)不同的水平上,研究亏缺灌溉对枸杞果实糖积累和蔗糖代谢相关酶活性的影响。结果表明:随水分胁迫的增强,不同处理枸杞果实百粒重呈下降趋势,严重亏缺灌溉的T5百粒重显著低于其它处理;在枸杞全生育期果实己糖(葡萄糖、果糖)积累量递增,蔗糖积累量逐渐下降。且随亏缺灌溉的加重,红果期各处理果实己糖、蔗糖含量差异显著,其中T1、T2显著高于T5;枸杞果实全生育期转化酶活性保持在较高水平,呈先上升后下降趋势,红果期其活性下降保证了蔗糖的积累;蔗糖合成酶和蔗糖磷酸合成酶活性较低,呈下降趋势。且随水分胁迫的加强,合成酶活性呈上升趋势,这与水分胁迫愈重,愈有利于蔗糖积累相一致。亏缺灌溉提高了果实中己糖积累,改善了果实品质,但严重亏缺会降低果实产量。

A study was conducted on the effects of water deficit on accumulation of sugar and activity of sugar metabolism-related enzymes of Lycium barbarum through controlling irrigation amount to keep the soil water at different levels（T1,18.20%;T2,19.50;T3,20.60%;T4,22.40%;T5,23.50%）.The results showed that the 100-grain weight presented a descending trend with the intension of water stress,and it was significantly lower in T5 than that in other treatments.The hexose content（glucose and fructose） of Lycium barbarum L. presented a trend of escalation through the whole fruit development, and the sucrose accumulation declined gradually. The content of hexose and sucrose in each treatment had significant difference in mature stage, and it was significantly higher in T1 and T2 than in T5. The invertase activity sustained at a high level, and showed a trend of rise first, then fall. The decreased invertase enzyme activity is beneficial to sugar accumulation. The activity of sucrose synthase and sucrose phosphate synthase was low and showed a decreased trend. Synthase activity showed an uptrend along with the intension of water stress, which was consistent with sucrose accumulation trend. Water deficit increased hexose content and improved fruit quality, however, serious water deficit decreased fruit yield.