Effects of humic substance combination with nitrogen fertilizer on yield of water spinach and nitrogen activation coefficient in soil
Article Sidebar
Main Article Content
Abstract
This study aimed to investigate the effects of humic acid application in combination with nitrogen fertilizers on the growth and yield of water spinach, as well as to evaluate its influence on changes in the nitrogen activation coefficient. The experiment was conducted using a completely randomized design (CRD) with three replications and five treatments: (1) control without humic acid and nitrogen fertilizer application, (2) humic acid at 0.5 g combined with urea at 0.4 g/tray (HA0.50+Urea0.40), (3) humic acid at 1.0 g combined with urea at 0.4 g/tray (HA1.00+Urea0.40), (4) humic acid at 0.5 g combined with ammonium sulfate (AS) at 0.84 g/tray (HA0.50+AS0.84), and (5) humic acid at 1.0 g combined with AS at 0.84 g/tray (HA1.00+AS0.84). The results demonstrated that HA0.50+Urea0.40 produced the highest fresh yield of water spinach (245 g/tray). Meanwhile, humic acid applied at 1.0 g/tray resulted in the highest plant nitrogen concentration, with comparable values observed under HA1.00+Urea0.40 and HA1.00+AS0.84 treatments (28.8 and 28.6 g/kg, respectively). Post-harvest soil analysis revealed that HA0.50+Urea0.40 significantly enhanced soil available nitrogen, reaching 61.8 mg/kg, with ammonium-N and nitrate-N concentrations of 50.2 and 11.67 mg/kg, respectively. Furthermore, the highest nitrogen activation coefficient (NAC) was observed under HA0.50+Urea0.40 (3.47%). Overall, the application of humic acid at 0.5 g combined with urea at 0.4 g/tray was identified as an effective strategy for improving water spinach productivity and enhancing nitrogen availability in soil. This combination also promoted greater nitrogen activation coefficient.
Article Details
This work is licensed under a Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License.
Articles in this journal are copyrighted by the x may be read and used for academic purposes, such as teaching, research, or citation, with proper credit given to the author and the journal.use or modification of the articles is prohibited without permission.
statements expressed in the articles are solely the opinions of the authors.
authors are fully responsible for the content and accuracy of their articles.
other reuse or republication requires permission from the journal."
References
คณาจารย์ภาควิชาปฐพีวิทยา. (2548). ปฐพีวิทยาเบื้องต้น. กรุงเทพ ฯ: สำนักพิมพ์มหาวิทยาลัยเกษตรศาสตร์.
ธรรมธวัช แสงงาม, ธงชัย มาลา, ศุภชัย อําคา และกนกกร สินมา. (2558). ผลของสารฮิวมิก และแคลเซียมซิลิเกตที่มีต่อการเจริญเติบโตของแตงเทศพันธุ์แอคชัน 434 และสมบัติบางประการของดินชุดดินกําแพงแสน. วารสารวิทยาศาสตร์และเทคโนโลยี มหาวิทยาลัยเกษตรศาสตร์, 4(1), 12-22.
ยงยุทธ โอสถสภา, อรรถศิษฐ์ วงศ์มณีโรจน์ และ ชวลิต ฮงประยูร. (2556). ปุ๋ยเพื่อการเกษตรยั่งยืน. กรุงเทพ ฯ: สำนักพิมพ์มหาวิทยาลัยเกษตรศาสตร์.
สถาบันวิจัยพืชสวน. (2568). การปลูกผักบุ้งจีน. เข้าถึงได้จาก: https://www.doa.go.th/hort/wp-content/uploads/2021/10/การปลูกผักบุ้งจีน.pdf (สืบค้นเมื่อ: 12 มีนาคม 2568).
Amin, M.E.M.H. (2011). Effect of different nitrogen sources on growth, yield and quality of fodder maize (Zea mays L.). Journal of the Saudi Society of Agricultural Sciences, 10, 17–23.
da Silva Rangel, G., de Souza Pastor, T., Ferreira, V.R., de Oliveira Costa, T., Carvalho, R.C.B., de Oliveira Souza, M., Berilli, A.P.C.G. & da Silva Berilli, S. (2026). Influence of nitrogen sources on physiological processes and morphological development of yellow passion fruit seedlings. Nitrogen, 7, Article 8.
FAO Project Staff and Land Classification Division. (1973). Soil Interpretation Handbook for Thailand. Land Classification Division, Department of Land Development, Bangkok.
Jackson, M. L. (1965). Soil chemical analysis. Prentice Hall, Inc.
Jin, Y., Yuan, Y., Liu, Z., Gai, S., Cheng, K. & Yang, F. (2024). Effect of humic substances on nitrogen cycling in soil-plant ecosystems: Advances, issues, and future perspectives. Journal of Environmental Management, 351, Article 119738.
Khaled, H. & Fawy, H.A. (2011). Effect of different levels of humic acids on the nutrient content, plant growth, and soil properties under conditions of salinity. Soil and Water Research, 6(1), 21–29.
Ma, Y., Cheng, X. & Zhang, Y. (2024). The impact of humic acid fertilizers on crop yield and nitrogen use efficiency: A meta-analysis. Agronomy, 14, Article 2763.
Mulvaney, R.L. (1996). Nitrogen-inorganic forms. In D.L. Sparks, A.L. Page, P.A. Helmke, R.H. Loeppert, P.N. Soltanpour, M.A. Tabatabai, C.T. Johnston & M.E. Sumner (Eds). Methods of soil analysis part 3: Chemical methods (pp. 1123-1184). Soil Science Society of America, Inc.
Nelson, D. W., & Sommers, L. E. (1996). Total carbon, organic carbon, and organic matter. In D. L. Sparks, A. L. Page, P. A. Helmke, R. H. Loeppert, P. N. Soltanpour, M. A. Tabatabai, C. T. Johnston & M. E. Sumner (Eds.). Methods of soil analysis part 3: Chemical methods (pp. 961-1010). Soil Science Society of America, Inc.
Rhoades, J.D. (1996). Salinity: electrical conductivity and total dissolved solids. In D.L. Sparks, A.L. Page, P.A. Helmke, R.H. Loeppert, P.N. Soltanpour, M.A. Tabatabai, C.T. Johnston & M.E. Sumner (Eds). Methods of Soil Analysis Part 3: Chemical Methods (pp. 417-435). Soil Science Society of America, Inc.
Sukyankij, S., Sukyankij, S., & Panich-pat, T. (2023). Effect of co-fertilizer application and dolomite amendments on yield and grain quality of rice grown on post-active acid sulfate soil. AGRIVITA Journal of Agricultural Science, 45(2), 311-321.
Sukyankij, S., Khougsud, C., Phun-Iam, M., & Panich-Pat, T. (2025). Influence of silicon application on phosphorus uptake in rice and phosphorus availability in acid and neutral soils, Central Thailand. International Journal of Agriculture and Biology, 33, 330415.
Thomas, G.W. (1996): Soil pH and soil acidity. In D.L. Sparks, A.L. Page, P.A. Helmke, R.H. Loeppert, P.N. Soltanpour, M.A. Tabatabai, C.T. Johnston & M.E. Sumner (Eds). Methods of Soil Analysis Part 3: Chemical Methods (pp. 475-490). Soil Science Society of America, Inc.
Wang, Q., Li, S., Li, J. & Huang, D. (2024). The utilization and roles of nitrogen in plants. Forests, 15, Article 1191.
Wu, Q., Zhang, S., Zhu, P., Huang, S., Wang, B., Zhao, L., & Xu, M. (2017). Characterizing differences in the phosphorus activation coefficient of three typical cropland soils and the influencing factors under long-term fertilization. PLoS One, 12, Article e0176437.
Xu, Y., Li, M., Ding, H., Ma, Y., Yang, Y. & Feng, L. (2025). Comparative effects of humic acid biostimulation on soil properties, growth, and fragrance of Rosa rugosa. Industrial Crops and Products, 225, 120444.
Yang, F., Tang, C. & Antonietti, M., (2021). Natural and artificial humic substances to manage minerals, ions, water, and soil microorganisms. Chemical Society Reviews, 50, 6221-6239.
Yang, X., Chen, X., & Yang, X. (2019). Effect of organic matter on phosphorus adsorption and desorption in a black soil from Northeast China. Soil and Tillage Research, 187, 85-91.
Zhang, S., Yuan, L., Li, W., Lin, Z., Li, Y., Hu, S. & Zhao, B. (2019). Effects of urea enhanced with different weathered coal-derived humic acid components on maize yield and fate of fertilizer nitrogen. Journal of Integrative Agriculture, 18(3), 656–666.
Zhong, N., Cai, Q. & Huang, J. (2025). Synergistic regulation mechanism of nitrogen and potassium coupling on sugarcane yield and soil quality in karst areas. Frontiers in Plant Science, 16, Article 1614682.
