保水剂施用方式对土壤酶活性及马铃薯产量的影响

Effects of application method of super absorbent polymers on soil enzyme activities and potato yield

【目的】研究不同保水剂施用方式对内蒙古西部半干旱偏旱地区土壤酶活性及马铃薯产量的影响,以筛选出合适的保水剂及施用方式。【方法】以聚丙烯酰胺(PAM)和聚丙烯酸钾(PAA-K)为材料,设不施保水剂(CK)、穴施PAM、沟施PAM、穴施PAA-K、沟施PAA-K 5个处理,分析不同保水剂及其施用方式下马铃薯不同生育时期、不同土层土壤过氧化氢酶、脲酶、蔗糖酶活性和产量的变化。【结果】土壤过氧化氢酶、脲酶、蔗糖酶活性随马铃薯生育时期的推进呈现"单峰"曲线变化,均于马铃薯块茎膨大期达峰值。与CK相比,施用保水剂处理均能提高土壤过氧化氢酶、脲酶、蔗糖酶活性,且对于同一种保水剂,穴施处理提高幅度大于沟施处理。在马铃薯块茎膨大期,穴施PAM、穴施PAA-K、沟施PAM、沟施PAA-K处理0~10cm土层的土壤过氧化氢酶活性较对照分别提高了12.92%,11.97%,9.06%和6.02%,土壤脲酶活性较对照分别提高了12.38%,2.33%,0.86%和0.31%,土壤蔗糖酶活性较对照分别提高了22.99%,17.03%,20.50%和18.34%,土壤过氧化氢酶、脲酶、蔗糖酶活性随土层的增加逐渐降低。与CK相比,施用保水剂显著提高了马铃薯产量和商品薯率,降低了小薯率。穴施PAM、穴施PAA-K、沟施PAM、沟施PAA-K分别较对照增产12.08%,10.45%,7.37%和5.22%。【结论】施用保水剂PAM、PAA-K均提高了土壤过氧化氢酶、脲酶、蔗糖酶活性及马铃薯产量和商品薯率,降低了小薯率,其中穴施PAM效果最好。

[Objective] The effect of different super absorbent polymers application methods on soil en- zyme activities and potato yield in semi-arid partial drought region of western Inner Mongolia was re- searched to select best application method. [Method] Polyacrylamide （PAM） and polyacrylic acid potassi- um （PAA-K） super absorbent polymers were used and five treatments including hole and furrow applying PAM and PAA-K and control （CK） were conducted to analyze the changes in catalase,urease and invertase activities at different soil layers during different potato stages and potato yield. [Result] Catalase, urease and invertase activities presented an unimodal curve with growth of potato,and reached the peaks at potatotuber expansion stage. All super absorbent polymers treatments improved soil catalase, urease and invertase activities compared with control group,and hole application increased more than furrow application. At tu- ber expansion period, compared with control group, hole applied PAM, hole applied PAA-K, furrow applied PAM and furrow applied PAA-K increased catalase activity by 12.92% ,11.97% ,9.06% ,and 6.02% ,increased urease activity by 12. 38%, 2. 33%, 0. 86%, and 0. 31%, and increased invertase activity by 22.99% ,17.03% ,20.50% ,and 18.34% in 0 to 10 cm soil layer. The activities decreased with increase of soil depth. Application of super absorbent polymers improved potato yield and potato commodity rate sig- nificantly, and reduced small potato rate. Hole applied PAM, hole applied PAA-K, furrow applied PAM, and furrow applied PAA-K increased yield by 12.08%, 10.45 %, 7.37 % and 5.22 %, respectively. [Conclusion] Application of super absorbent polymers PAM and PAA-K improved the catalase,urease and invertase ac- tivities as well as potato yield and commodity potato rate, and decreased small potato rate. Hole applied PAM treatment presented the best effect.