追肥减施下加气对番茄生长及土壤酶活性的影响

[目的] 为探究化肥减施条件下加气对作物生长特性和根层土壤特征的影响。[方法] 通过开展连续2年野外田间试验,以宁夏银北灌区大田栽培番茄为研究对象,设置4组微纳米加气比例(0,5%,10%,15%)和3个追肥(尿素—重过磷酸钙—硫酸钾)水平(180—400—480,135—300—360,90—200—240 kg/hm²)。[结果] 在相同追肥水平下,植株的干物质和营养元素(氮、磷、钾)积累量随加气比例增加而增加,提高加气比例有利于番茄开花坐果期根系磷素积累和果实膨大期钾素积累;在相同追肥水平下提高加气比例5%~15%对应番茄产量增加14.0%~44.2%;在相同加气比例下相对传统施肥模式适当降低追肥水平(-25%)对应番茄产量增加0.4%~9.1%;提高加气比例和追肥水平有利于在番茄开花坐果期和果实膨大期显著提高土壤相关酶(过氧化氢酶、碱性磷酸酶和脲酶)活性,相同追肥水平下提高加气比例5%~15%对应土壤相关酶活性提高27.5%~122.9%。[结论] 在宁夏银北灌区地埋滴灌条件下,为促进植株生长、稳定番茄产量和提高土壤酶活性,适宜的“尿素—重过磷酸钙—硫酸钾”追施水平为180—400—480 kg/hm²(相对传统追肥定额减施25%),适宜的微纳米加气比例为10%。

Effects of Aeration on Tomato Growth and Soil Enzyme Activity Under the Conditions of Topdressing Fertilizer Reduction

[Objective] The study aimed to explore the effects of aeration on crop growth characteristics and soil environmental characteristics in the root zone under reduced topdressing conditions. [Methods] The present paper took the field cultivated tomato in Yinbei irrigation area of Ningxia as the research object. Four groups of micro-nano gas aeration ratios (0, 5%, 10%, and 15%) and three topdressing fertilizer (urea-triple superphosphate-potassium sulfate) levels (180-400-480 kg/hm², 135-300-360 kg/hm², and 90-200-240 kg/hm²) were set up for the two-year field experiment conducted in 2019 and 2020. [Results] With the same topdressing level, the dry matter and nutritional elements (N, P, and K) accumulation in the plant increased with the increase of aeration ratio, and increasing the aeration ratio was beneficial to the accumulation of phosphorus in roots during flowering-fruit setting period and the potassium accumulation at fruit expansion stage. With the same topdressing level, the tomato yield increased by 14.0%~44.2% as the aeration ratio increased by 5%~15%. With the same aeration ratio, the tomato yield increased by 0.4%~9.1% as the topdressing level was appropriately reduced (-25%) compared with the traditional fertilization. The increase of the aeration ratio and topdressing level was beneficial to increase the soil enzymes (catalase, alkaline phosphatase, and urease) activity significantly during the flowering-fruit setting period and fruit enlargement period of tomato. With the same topdressing level, increasing the aeration ratio by 5%~15% corresponded to an increase in soil enzyme activity by 27.5%~122.9%. [Conclusion] It was suggested that, to promote tomato plant growth, stabilize tomato yield and improve the soil enzymes activity in the Yinbei irrigation district, the suitable topdressing level of "urea-triple superphosphate-potassium" was 135-300-360 kg/hm² (25% lower than the traditional topdressing amount), and the suitable micro-nano aeration ratio was 10%.