东方百合‘索邦’鳞茎源--库转化过程中碳水化合物代谢及相关酶活性变化

Carbohydrate metabolism and activity variation of related enzymes during the exchanging role of bulb source and sink of oriental hybrid lily‘Sorbonne’

利用紫外分光光度计法对东方百合‘索邦’鳞茎源--库转换过程中碳水化合物含量及其蔗糖和淀粉合成相关的主要酶活性进行了测定,并分析了它们之间的相关性。结果表明:自栽种期至花蕾发育中期(花蕾长度达到3cm),外层、中层鳞片中淀粉含量均呈现下降趋势,鳞茎此时作为源提供营养物质;此后至盛花期,外层鳞片中淀粉含量呈现下降趋势而中层鳞片中呈现上升趋势,说明鳞茎在此时表现为源--库复合体时期;之后鳞茎作为库积累营养物质。此外,外层鳞片和中层鳞片内蔗糖与蔗糖合酶(SS)、蔗糖磷酸合酶(SPS)之间表现为正相关,而SS和SPS与淀粉含量均表现为负相关,但均不显著。除中层鳞片内可溶性淀粉合酶(SSS)与淀粉含量表现为相关系数很低的负相关外,外层和中层鳞片中与淀粉合成相关的腺苷二磷酸葡萄糖焦磷酸化酶(AGPase)、淀粉合酶(SSS和颗粒结合型淀粉合酶GBSS)都与淀粉积累表现为正相关,尤其是外层鳞片中SSS和GBSS均与淀粉含量表现为极显著的正相关,且这3种酶均与蔗糖含量表现为负相关。说明百合鳞茎中淀粉合成相关的酶可以作为百合鳞茎源或库功能的重要参考指标,鳞茎的库强与SSS和GBSS活性关系最密切,可以作为影响鳞茎库强的主要因子。

UV spectrophotometer methods were used to assay the carbohydrate contents and activities of related enzymes of oriental hybrid lily ＇ Sorbonne＇ , and their correlations were analyzed using SPASS. The results showed that： the content of starch in outer and middle scales showed a downward trend from planting to flower bud developing to 3 cm in length, which indicated that the bulb served as source during this process; thereafter to anthesis, the metabolism of starch in the outer and middle scales showed the opposite directions, indicating that the bulbs served as the source-sink complex; from then on, the bulbs became sink to accumulate nutrients. Besides, sucrose and sucrose synthesis enzymes （SS） and sucrose phosphate synthase （SPS） in outer and middle scales showed positive correlations respectively, while starch content and SS and SPS showed negative correlations, all of which were not statistically significant. Furthermore, except that the soluble starch synthase （SSS） and starch content in middle scales showed alow negative correlation, the starch content and the adenosine diphosphate glucose pyrophosphorylase （AGPase） , and starch synthase （SSS and granule-bound starch synthase GBSS） in outer and middle scales showed positive correlation, especially the correlation between starch content and SSS and GBSS in the outer scales, which were high positive and significant. Three enzymes relating to starch synthesis showed negative correlation with sucrose content. The activities of enzymes relating to starch synthesis can serve as important references for the source or sink function of lily bulbs. The activities of SSS and GBSS played more significant roles in deciding the sink strength of lily bulbs, which can be used as indicators for the sink strength of lily bulbs.