黑膜覆盖对旱地马铃薯块茎淀粉积累和关键酶活性的影响

为探明宁南半干旱雨养农业区马铃薯块茎中淀粉和关键酶活性对黑色地覆盖膜的响应机理,在2016年和2017年以宁南山区马铃薯主栽品种青薯9号为材料,通过两年大田试验,研究了黑膜覆盖(BF)、白膜覆盖(WF)和不覆膜(NF)对马铃薯块茎中淀粉及其组分积累、淀粉合成关键酶活性的影响。结果表明,与WF和NF相比,BF的直链淀粉、支链淀粉、总淀粉含量分别增加11.37%~35.68%、8.56%~27.05%、8.33%~27.60%,淀粉积累速率提高13.80%~37.90%;BF、WF、NF条件下块茎ADPG焦磷酸化酶(AGPase)、UDPG焦磷酸化酶(UGPase)、淀粉分支酶(SBE)、可溶性淀粉合酶(SSS)、束缚态淀粉合酶(GBSS)活性均呈单峰曲线变化,BF的淀粉合成关键酶活性明显高于WF和NF。与WF和NF相比,BF的AGPase活性分别增加12.81%和40.24%;UGPase活性分别增加15.34%和36.52%、SBE活性分别增加16.64%和44.17%、SSS活性分别增加13.69%和34.76%、GBSS活性分别增加15.75%和45.44%。BF产量较WF和NF分别提高14.54%和57.23%。相关分析表明,马铃薯块茎中直链淀粉、支链淀粉和总淀粉含量与AGPase、UGPase、SBE、SSS、GBSS活性在多数测定时期呈正相关(P<0.01)。因此,在干旱半干旱地区采用黑色地膜覆盖栽培能够通过影响淀粉合成关键酶,进而提高马铃薯块茎中的淀粉及其组分含量,最终影响马铃薯的产量。

Effects of Black Plastic Film Mulching on Starch Accumulation and Key Enzyme Activities of Potato Tubers in Dryland

In order to find out the response mechanism of starch accumulation and key enzyme activities to black plastic film mulching in potato tubers in semi-arid rain-red agriculture area of southern Ningxia. In 2016 and 2017, the main plant variety Qingshu No.9 in the mountainous area of Ningnan was used as experimental material. Two-year field experiment was conducted to study effects of black film(BF),white film(WF) and no-film on the accumulation of starch and its components and the activity of key enzymes of starch synthesis in potato tuber. Results showed that compared with WF and NF, BF treated amylose, amylopectin and total starch content increased by 11.37-35.68%, 8.56-27.05%, 8.33-27.60%, respectively, and starch accumulation rate increased by 13.80-37.90%. Under the condition of BF, WF and NF, the activity of tuber ADPG pyrophos phorylase(AGPase), UDPG pyrophos phorylase(UGPase), starch branching enzyme(SBE), soluble starch synthase(SSS), and granule-bound starch synthetase(GBSS), showed a single peak curve. The key enzyme activity of starch synthesis in BF was significantly higher than that in WF and NF. Compared with WF and NF, under BF treatment, AGPase activity was increased by 12.81% and 40.24% with UGPase activity increased by 15.34% and 36.52%, SBE activity increased by 16.64% and 44.17%, SSS activity increased by 13.69% and 34.76%, and GBSS activity increased by 15.75% and 45.44%, respectively. The yield of BF increased by 14.54% and 57.23% compared with WF and NF. Correlation analysis showed that amylose, amylopectin and total starch content in potato tubers were positively correlated with AGPase, UGPase, SBE, SSS and GBSS activities in most of the periods (P<0.01). Therefore, the use of black plastic film mulching cultivation in arid and semi-arid areas affects the starch and its components in potato tubers by affecting starch-related enzymes, which ultimately affects potato yield.