Effects of organic liquid fertilizers on biological activities and fruit productivity in open-field cherry tomato

ABSTRACT This study evaluated the effects of liquid fertilizers (LF) with farm-derived renewable resources on biological activities and chemical attributes of the soil and fruit in an open-field tomato (Lycopersicon esculentum var. cerasiforme) experiment conducted in South Korea in the 2019 growing season. The LF treatments included bone+fish meal (BF), fish+phosphoric acid (FP), sesame oil (SO), starfish (SF), nontreatment (NT) as control, and oil cake (OC) as an organic fertilizer, fertigating two times per week during the growing season. The pH in LF ranged between 7.4 and 8.3, and electrical conductivity in the LF was the highest on SF (0.69 dS·m-1), SO (0.64 dS·m-1), and BF (0.45 dS·m-1). Total amount of total-N supplied was the highest for SF (679 mg·plant-1), SO (654 mg), and BF (333 mg). The number of some invertebrates was increased by the BF and SF treatments. Earthworm biomass was significantly increased by the SF treatment. The NT and OC treatments reduced operational taxonomic units and the richness estimator of Chao1 and ACE. Seasonal SPAD and PS II values in the leaves were reduced on the FP-plants on 45 and 60 days after fertigation. The SF treatment increased fruit fresh weight and fruit yield to 4.2 kg per plant, with similar results observed for BF-treated plants. Fruit yield efficiency was improved by the BF treatment, followed by SO and SF among all the treatment. Starfish would be the promising LF for use as a supplemental nutrient amendment to increase agroecosystem health, nutrient availability, and fruit productivity.

摘要 本研究针对2019年生长季于韩国开展的大田樱桃番茄（*Lycopersicon esculentum* var. *cerasiforme*）种植试验，评估了以农场可再生资源为原料制备的液体肥料（liquid fertilizers, LF）对土壤与果实的生物活性及化学特性的影响。试验设置的液体肥料处理包括：骨粉+鱼粉（bone+fish meal, BF）、鱼粉+磷酸（fish+phosphoric acid, FP）、芝麻油肥（sesame oil, SO）、海星源肥（starfish, SF）、不施肥对照（nontreatment, NT），以及油饼有机肥（oil cake, OC），生长季内每周随水追肥2次。供试液体肥料的pH值介于7.4~8.3之间；其电导率（electrical conductivity, EC）以SF组最高（0.69 dS·m⁻¹），其次为SO组（0.64 dS·m⁻¹）与BF组（0.45 dS·m⁻¹）。单株总氮（total-N）供给总量以SF组最高（679 mg·株⁻¹），其次为SO组（654 mg）与BF组（333 mg）。BF与SF处理可提升部分无脊椎动物的种群数量，SF处理可显著提升土壤蚯蚓生物量。NT与OC处理则降低了土壤微生物的操作分类单元（operational taxonomic units, OTU）数量以及Chao1、ACE丰富度估计值。追肥后45天与60天，FP处理组番茄叶片的SPAD值与光系统Ⅱ（Photosystem Ⅱ）活性均出现下降。SF处理使单株果实鲜重与产量提升至4.2 kg，BF处理组表现与之相近。BF处理可提升果实产量效率，其余表现优异的处理依次为SO与SF。综上，海星源液体肥料可作为优质养分补充改良剂，能够提升农田生态系统健康水平、养分有效性与果实生产力，具备良好的应用前景。