化肥和生物有机肥配施对鲜食型甘薯块根产量、品质及土壤肥力的影响

  【目的】  研究生物有机肥和化肥对鲜食型甘薯干物质积累、产量品质及土壤肥力的影响，为鲜食型甘薯的优质高效生产提供技术支撑。  【方法】  2018和2019年，以鲜食型主栽品种‘济薯26’为供试品种，在山东济南丘陵区进行了两年定位田间试验。设置不施肥(对照)、单施化肥、单施生物有机肥、化肥生物有机肥配施处理。在移栽后50、100和150天，取样分析植株干物质积累和分配。于成熟期，调查分析块根产量及品质，以及0—20 cm土层土壤肥力指标。  【结果】  与单施化肥相比，单施生物有机肥和化肥生物有机肥配合处理均显著提高了两年度移栽后150天甘薯植株干重和块根干重，块根产量以化肥配合生物有机肥处理最高，单施生物有机肥次之，均显著高于单施化肥。与单施化肥相比，单施生物有机肥可显著提高两个年度土壤脱氢酶和蔗糖酶活性，显著提高第二年度土壤脲酶和碱性磷酸酶活性及土壤速效磷、速效钾和有机质含量，促进干物质向块根分配，显著提高了第二年度块根还原糖、可溶性糖和维生素C含量。与施用生物有机肥相比，化肥生物有机肥配施显著提高了两个年度移栽后100天和150天植株干重和块根干重，显著提高第二年度土壤碱性磷酸酶和脱氢酶活性，提高土壤碱解氮和速效磷含量，还原糖和可溶性糖含量无显著变化，但显著增加类胡萝卜素和维生素C含量。相关分析表明，块根品质指标与土壤有机质、速效磷和速效钾含量显著正相关，与土壤酶活性亦有显著正相关关系。  【结论】  连续进行化肥与生物有机肥配施，可显著提高土壤碱性磷酸酶和脱氢酶活性，增加土壤碱解氮和速效磷含量，促进甘薯植株和块根干物质的持续积累，获得高产，同时保持较高的块根糖含量和维生素C含量，是提高鲜食型甘薯产量和品质的有效措施。

Effects of chemical and bio-organic fertilizers on tuber yield,quality, and soil fertility of edible sweetpotato

  【Objectives】  We compared the effects of chemical and bio-organic fertilizers on sweetpotato’s yield and quality to provide fertilization support for its efficient and high-quality production.  【Methods】  Field experiments were conducted in the hilly area of Jinan, Shandong Province, in 2018 and 2019 using sweetpotato cultivar ‘Jishu 26’ as the test material. The four treatments included no fertilization (i.e., control), single chemical fertilizer (T1), bio-organic fertilizer (T2), and combined chemical and bio-organic fertilizer application (T3). The plant samples were collected at 50, 100, and 150 days after planting (DAP) to measure dry matter accumulation (DMA) and root yield. Tuber quality and soil fertility in 0–20 cm soil depth were analyzed at the harvest stage.   【Results】  Compared with T1, T2 and T3 increased DMA in plants and roots at 150 DAP in both years (P < 0.05) . The highest and lowest root yield was recorded in T3 and T1, respectively. Compared with T1, T2 increased soil dehydrogenase and sucrase activities in both years and increased soil urease and alkaline phosphatase activities in 2019 (P < 0.05) . Similarly, soil available P, K, organic matter, reducing sugar content, soluble sugar, and vitamin C increased in the tubers in T2, promoting dry matter translocation to the tubers. Compared with T2, T3 (P < 0.05) increased DMA in plants and tubers at 100 and 150 DAP in both years and increased soil alkaline phosphatase and dehydrogenase activities in 2019. Soil alkaline phosphatase and dehydrogenase were beneficial to increasing soil alkali-hydrolyzable N and available P. For the root quality, T3 increased the contents of carotenoids and vitamin C in the tubers and showed no significant effect on reducing sugar and soluble sugar contents. The tuber quality indexes were (P < 0.05) positively correlated with soil organic matter, available P, readily available K, and soil enzyme activities.   【Conclusions】  Continuous chemical and bio-organic fertilizers application increased soil alkaline phosphatase and dehydrogenase activities, benefiting high soil alkali-hydrolyzable N and available P contents. The mixed fertilizer application promoted higher dry matter accumulation, root yield, sugar and vitamin C contents in the tubers. Our results demonstrate that mixed fertilizer application is suitable for efficient and high-quality production of edible sweetpotato.