水分胁迫对‘桂味’荔枝果实发育及糖代谢的影响

【目的】为研究水分胁迫对荔枝果实的生长发育、糖代谢及产量的影响,【方法】以15 a生‘桂味’荔枝(Litchichinensis Sonn‘Guiwei’)为试材,设以灌溉和水分胁迫2个不同的土壤水分处理。【结果】结果表明,水分胁迫下荔枝果实的大小、单果质量降低,果实发育受到抑制。水分胁迫的荔枝坐果率显著降低,同时导致最终产量的下降。对水分胁迫条件下糖积累的研究发现,‘桂味’荔枝前期以积累还原糖为主,果实发育后期主要积累蔗糖;胁迫处理的荔枝果实糖含量前期低于灌溉的,后期总糖、蔗糖及还原糖含量都高于灌溉处理的。在荔枝果实发育后期,分解蔗糖的酸性转化酶(AI)、蔗糖合成酶(SS)及合成蔗糖的蔗糖磷酸合成酶(SPS)的活性都为水分胁迫的高于灌溉处理的,这将有助于增加胁迫的果实库强及糖的积累。【结论】因此为使果实正常生长及提高产量和品质,生产上果实发育前中期应保持足量均衡的水分供应,后期不需要过多水分。

Effect of water stress on litchi fruit development and sugar metabolism

【Objective】 The research is to study the growth,sugar metabolism and yield of litchi fruit under water stress.【Method】 The experimental materials,Litchi chinensis Sonn.’Guiwei’,were put under two different soil water conditions: irrigation and water stress.【Result】 The results showed that the size and single fruit weight decreased under water stress and the growth was suppressed,meanwhile both the fruit set and yield significantly decreased under water stress.’Guiwei’ litchi accumulated more sucrose in fruit than reducing sugar at early stage,while more reducing sugar than sucrose in later period.The sugar concentrations were lower under water stress than irrigation at early stage,but increased after 14th June.At the same time,the activity of acid invertase(AI) and sucrose synthase(SS) which were sucrose cleave enzymes,and activity of sucrose phosphate synthase(SPS) were higher under water stress than irrigation treatment,which contributed to the increase of fruit sink strength and sugar accumulation.【Conclusion】The results indicated that adequate water should be supplied at early stage of litchi fruit development and the water supply should be limited in later period in order to get high yield and quality.