施钾对宁南旱区马铃薯块茎淀粉含量及淀粉合成相关酶活性的影响

Effects of potassium application on starch content and enzyme activities associated with starch synthesis in potato tuber in arid areas of southern Ningxia

【目的】研究施钾水平对宁南旱区马铃薯块茎淀粉含量和淀粉合成关键酶活性的影响。【方法】以青薯9号为试验材料,设置8个钾肥处理(CK为对照不施N、P、K肥,K_(0):0 kg/hm^(2),K_(1):30 kg/hm^(2),K_(2):60 kg/hm^(2),K_(3):90 kg/hm^(2),K_(4):120 kg/hm^(2),K_(5):150 kg/hm^(2),K_(6):180 kg/hm^(2)),在各关键生育时期分别测定马铃薯块茎的总淀粉含量、直链淀粉含量、支链淀粉含量和淀粉合成关键酶活性,探讨不同施钾量对旱作马铃薯淀粉形成的影响。【结果】随着施钾量增加,马铃薯块茎中的总淀粉、直链淀粉与支链淀粉含量均呈现先升后降的单峰曲线变化趋势,并在K3处理下达到最大值。K_(3)施钾水平较CK和K0处理的总淀粉、直链淀粉与支链淀粉含量分别提高了28.6%、41.48%、23.06%和28.0%、31.34%、13.95%。腺苷二磷酸葡萄焦磷酸化酶(ADPG-PPse)、尿苷二磷酸葡萄焦磷酸化酶(UDPG-PPase)、可溶性淀粉合成酶(SSS)、颗粒凝结型淀粉合成酶(GBSS)、淀粉分支酶(SBE)等淀粉合成相关酶活性从大到小的顺序为:K_(3)>K_(4)>K_(5)>K_(6)>K_(2)>K_(1)>K_(0)>CK。【结论】施钾量90 kg/hm^(2)时能够提高马铃薯淀粉合成酶活性,促进块茎淀粉的合成与积累。

【Objective】This study aimed to investigate the impact of potassium application on starch content and the activity of starch synthesis in southern Ningxia.【Method】Qingpotato 9 was used as the test material,and eight potash fertilizer treatments were applied(CK without N,P,K fertilizer;K_(0) at 0 kg/hm^(2);K_(1) at 30 kg/hm^(2);K_(2) at 60 kg/hm^(2);K_(3) at 90 kg/hm^(2);K_(4) at 120 kg/hm^(2);K_(5) at 150 kg/hm^(2);K_(6) at 180 kg/hm^(2)).The total starch content,amylose content,and activities of key starch synthesis enzymes in potato tubers were determined during critical reproductive periods to investigate the effect of different potassium dosages on starch formation in dry potatoes.【Result】The results demonstrated that with increasing potassium appli-cation,the total starch,amylose,and amylopectin initially increased and then decreased,reaching their maxi-mum value under the K3 treatment.Compared to the CK and K0 treatments,the K_(3) treatment showed an in-crease of 28.6%,41.48%,23.06%,31.34%,31.34%,and 13.95%in total starch,amylose,amylopectin,adenylate pyrophosphorylase(ADPG-PPase)activity,uridine diphosphate glucose pyrophosphorylase(UDPG-PPase)activity,and soluble starch synthetase(SSS)activity,respectively.The order of potas-sium application for the key starch synthesis enzymes ADPG-PPase,UDPG-PPase,SSS,and granule-bound starch synthase(GBSS)was as follows:K_(3)>K_(4)>K_(5)>K_(6)>K_(2)>K_(1)>K_(0)>CK.【Conclusion】It can be concluded that a potassium application of 90 kg/hm^(2) improves potato starch.