‘金冠’苹果及优系(SGP-1)果实糖积累与其代谢相关酶活性研究

Study on Sugar Accumulation and Metabolism Related Enzyme Activities in Fruit of‘Golden Delicious’Apple and Its Excellent Variation(SGP-1)

以‘金冠’苹果及其优系(SGP-1)为试材,测定果实发育期间可溶性糖及组分含量和代谢相关酶活性,分析它们的变化规律及相关关系,明确糖分积累的关键时期和关键酶,探讨两材料果实生长发育期间糖代谢的生理差异。结果表明:(1)两材料果实中可溶性糖呈上升趋势,在果实发育前期,‘SGP-1’可溶性糖的含量显著高于‘金冠’,到后期则显著低于‘金冠’。(2)两材料果糖、蔗糖、葡萄糖和山梨醇含量变化趋势一致,除山梨醇外,总体呈上升趋势。前期‘SGP-1’山梨醇含量显著高于‘金冠’;后期果糖和葡萄糖含量显著高于‘金冠’,蔗糖和山梨醇则显著低于‘金冠’,且两材料成熟果实均以果糖占比最高。(3)‘金冠’与‘SGP-1’果实的糖代谢酶活性在前期变化趋势不同,后期基本一致;‘SGP-1’总体表现为前期显著高于‘金冠’,后期除SOX高于‘金冠’,其余酶活性持平或显著低于‘金冠’。(4)相关性分析表明,果实发育前期‘SGP-1’果实各糖组分含量主要受SDH、SS-S调控,而‘金冠’则主要受SDH、NI调控;后期‘SGP-1’果实各糖组分含量主要受SPS、NI调控,而‘金冠’则主要受SPS、SS-C和AI调控。研究发现,‘SGP-1’果实糖积累的关键期为发育前期,而‘金冠’则在发育后期快速积累,且对两材料糖积累起主要调控作用的酶活性和种类存在差异。

Taking ‘Golden Delicious’ apple and its excellent variation(SGP-1) as test materials, the soluble sugar components, content and metabolism related enzyme activities during fruit development were measured, their change rules and correlation were analyzed, and the main period and main enzymes of sugar accumulation were determined, so as to explore the physiological differences of sugar metabolism in the whole fruit development period of the two materials.The results showed that:(1) the soluble sugar in the fruit of ‘Golden Delicious’ apple and ‘SGP-1’ showed an upward trend.at the early and middle stages of fruit development, the accumulation of soluble sugar in the fruit of ‘SGP-1’ was significantly higher than that of ‘Golden Delicious’ apple, and was significantly lower than that of ‘Golden Delicious’ apple at the later stage.(2) During the fruit development period, except for sorbitol, the change trends of fructose, sucrose, glucose and sorbitol of the two materials were consistent, which showed an overall upward trend.The sorbitol content of ‘SGP-1’ was significantly higher than that of ‘Golden Delicious’ apple at the early stage;the content of fructose and glucose at the later stage was significantly higher than that of ‘Golden Delicious’ apple and the sucrose and sorbitol were significantly lower than those of ‘Golden Delicious’ apple.The proportion of fructose in the soluble sugar of the two materials was the highest.(3) The sugar metabolizing enzyme activities of ‘Golden Delicious’ apple and ‘SGP-1’ were different at the early stage, but it was basically same at the later stage.At the early stage, the overall performance of ‘SGP-1’ was significantly higher than that of ‘Golden Delicious’ apple.At the later stage, except that SOX was higher than that of ‘Golden Delicious’ apple, the rest of the enzyme activities were flat or significantly lower than ‘Golden Delicious’ apple.(4) Correlation analysis showed that the content of sugar components in fruit of ‘SGP-1’ was mainly regulated by SDH and SS-S at the early stage, while ‘Golden Delicious’ apple was mainly regulated by SDH and NI.It was mainly regulated by SPS and NI at the later stage, while ‘Golden Delicious’ apple was mainly regulated by SPS, SS-C, and AI.This study found that the key period of sugar accumulation in ‘SGP-1’ fruit was at the early developmental stage, while the soluble sugars in ‘Golden Delicious’ apple rapidly accumulated at the later stage of development, and there were differences in the activities and types of enzymes that played a major role in regulating sugar accumulation between the two materials.