为提高河西绿洲灌区甜叶菊产量和品质，提升该区甜叶菊市场竞争力。以谱星6号为试验材料，比较了不同施钾水平(K2O 0、60、90、120、150 kg/hm2)对甜叶菊糖苷跃变期生理指标以及产量品质的影响。结果表明，不同施钾处理下，甜叶菊整个糖苷跃变期叶片各生理指标含量达到峰值的时间有所不同，叶片SOD活力、含钾量均在现蕾前5 d达到最高，可溶性蛋白、SPAD值、含氮磷量、总苷含量以及叶片干物质量在现蕾初期达到最高，POD活力、可溶性糖含量在现蕾后5 d达到最高，以上各指标均以施用K2O 120 kg/hm2处理表现最佳。其中总苷含量最高，达128.4 g/kg，较不施钾肥增加14.19%；产量也最高，达7 007.64 kg/hm2，较不施钾肥增加57.24%；净收益达5.26万元/hm2，比不施钾多3.40万元/hm2。通过甜叶菊叶片理化指标与产量品质的相关性分析，以上各生理指标与产量品质均呈现显著或者极显著的正相关关系。在当地甜叶菊生产中施用K2O 120 kg/hm2，且在现蕾初期采摘叶片可获得较好收益。

In order to increase the yield and quality of Stevia rebaudiana in Hexi Oasis Irrigation Area and to improve the market competitiveness of Stevia rebaudiana in the region, Puxing 6 was used as the test material and the effects of different levels of potassium fertilizer (K2O at 0, 60, 90, 120, 150 kg/ha, respectively) on the physiological indexes, yield and quality of stevioside during the transition period were compared. The results showed that under different potassium fertilization treatments, the timings when the content of each physiological index in the leaves of Stevia rebaudiana reached the peak value during the whole glycoside climacteric stage were different. The SOD activity and potassium content of the leaves peaked 5 days before budding, and the soluble protein content, SPAD value, contents of nitrogen and phosphorus, total glycosides content and dry matter content of leaves peaked at the initial stage of budding, and POD activity and soluble sugar content peaked 5 days after budding. The above indexes all performed the best in the treatment of 120 kg/ha among which the total glycosides content under this treatment yielded the highest number of 128.4 g/kg which was 14.19% higher compared with that of the control, yield under this treatment reached 7 007.64 kg/ha which was 57.24% compared with that of the control, and the net income reached 52 600 RMB/ha which was 34 000 RMB/ha more than that of the control. The correlation analysis of the above physiological indicators showed a significant or extremely significant positive correlation with yield and quality data. To sum up, it is recommended to apply 120 kg/ha of potassium(K2O) in local stevia production, and to harvest leaves at the early stage of budding to obtain better economic benefits.

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甘肃省青年科技基金计划项目(20JR5RA072、 20JR10RA484)；甘肃省知识产权计划-知识产权运用项目(22ZSCQ050)。