The study only considered a specific region (Horqin Sandy Land) and crop (oat)

The gap

Evidence profile

Sourced from the future-work section and limitations section and stated research gap and inline gaps and recommendations of the source papers, classified as general, spanning 5 journals.

Supporting evidence — 6 representative gaps

• Effects of Combined Peat Powder and Fermented Manure on Oat Yield, Soil Enzyme Activities and Microbial Community Composition in Horqin Sandy Land (2026) · Biology · doi

  Investigating the long-term effects of organic fertilizer application on soil fertility and crop productivity, - Examining the impact of different organic fertilizer ratios and application rates on various crops, - Studying the potential of other organic materials as fertilizers in sandy land

  generalfuture-work section
  Keywords: investigating long-term effects organic fertilizer application soil fertility
• Effects of Combined Peat Powder and Fermented Manure on Oat Yield, Soil Enzyme Activities and Microbial Community Composition in Horqin Sandy Land (2026) · Biology · doi

  The study only considered a specific region (Horqin Sandy Land) and crop (oat), - The experiment was conducted in a field setting with a limited number of replicates (4), - The study did not investigate the long-term effects of organic fertilizer application

  generallimitations section
  Keywords: study only considered specific region horqin sandy land
• Growth Responses and Production of Tomatoto Manure and Liquid Organic Fertilizer (2026) · Jurnal Hortikultura Indonesia · doi

  There is a need to study the effect of manure and liquid organic fertilizer on tomato plant growth and production. The study aims to fill this gap by determining the effect of applying various manures and the intensity of watering of banana hump liquid organic fertilizer.

  generalstated research gapevidence 5/5
  Keywords: there need study effect manure liquid organic fertilizer
• Effects of Mycorrhiza and Animal Manure Applications on Fruit Yield and Quality in Greenhouse Cucumber Cultivation (2026) · Artvin Çoruh Üniversitesi Orman Fakültesi Dergisi · doi

  There is a need for alternative fertilization management programs to provide plants with sufficient amounts of nutrients. The excessive use of chemical fertilizers in agricultural production has led to a decrease in yield and quality of agricultural products.

  generalstated research gapevidence 5/5
  Keywords: there need alternative fertilization management programs provide plants
• Comparative effects of homemade and commercial organic fertilizers on yield and fruit quality of cherry tomato (Solanum lycopersicum var. cerasiforme) in Northern Vietnam (2026) · Frontiers in Horticulture · doi

  4 Limitations of this study and future research directions This study was conducted at a single site during one growing season, which may limit the generalizability of the findings under different environmental conditions. The nutrient composition and release dynamics of the home- made organic fertilizer were not fully characterized, which may affect reproducibility due to variability in raw materials and composting processes, as widely reported in composting studies FIGURE 4 Representative images of cherry tomato fruits under different fertilizer treatments at harvest.

  generalinline gapsevidence 5/5
  Keywords: different fertilizer composting limitations future directions conducted single site growing season limit generalizability ndings environmental
• Effectiveness of a Natural Fertilizer from Organic Household Waste (Banana Peel, Orange Peel, Eggshell, and Onion Peel) versus Chemical Fertilizer on The Growth of Chili (Capsicum Annuum L.): A Comparative Analysis (2026) · International Journal of Smart Agriculture · doi

  Future studies should extend the duration of the experiment to evaluate the long-term effects of the organic fertilizer on plant yield and fruit production. Researchers are also encouraged to test additional fertilizer concentrations to determine the most effective application rate. Clear guidelines for comparison treatments should be provided to improve reproducibility. Home gardeners and farmers may use the 10 mL organic fertilizer formulation as a practical and affordable alternative to chemical fertilizers. The ingredients can also be manually crushed when blending equipment is unavailable. REFERENCES Bhargaw, A., Dasgupta, R., V. P. D., Hadimani, A., Shetty, M. G., & Ghosh, S. K. (2024). PRANAM-Ca: An eggshell derived calcium fertilizer and its impact on blossom end rot in tomato cultivation. Journal of Experimental Agriculture International, 46(2), 78–85. https://doi.org/10.9734/jeai/2024/v46i22310 Chandini, Kumar, R., Kumar, R., & Prakash, O. (2019, February). The impact of chemical fertilizers on our ecosystem. ResearchGate. https:// environment and www.researchgate.net/publication/331132826_ The_Impact_of_Chemical_Fertilizers_on_our_ Environment_and_Ecosystem Faisal, A. F., & Mustafa, Y. F. (2025). Chili pepper: A delve into its nutritional values and roles in food-based therapy. Food Chemistry Advances. https://doi.org/10.1016/j. focha.2025.100928 Fernando, J. R., Tenizo, A. J., & Villa, R. (2023). The effect of organic hydroponic solution from banana (Musa acuminata) peel, orange (Citrus sinensis) peel, and eggshell on the growth of pepper plants. Unpublished senior high school research paper; Exequiel R. Lina High School, Poblacion Norte, Licab, Nueva Ecija. Itamah, E., Bello, T. K., & Waziri, S. M. (2025). Production and characterization of liquid bio-fertiliser from orange peels, banana peels, and eggshell. Discover Agriculture, 3(1). https://doi.org/10.1007/s44279- 025-00342-0 Khaitov, B., Yun, H. J., Lee, Y., Ruziev, F., Le, T. H., Umurzokov, M., Bo Bo, A., Cho, K. M., & Park, K. W. (2019). Impact of organic manure on growth, nutrient content and yield of chilli pepper under 5 9 https://journals.e-palli.com/home/index.php/ijsa Page Int. J. Smart Agric. 4(1) 91-96, 2026various temperature environments. International Journal of Environmental Research and Public Health, 16(17), 3031. https://doi.org/10.3390/ijerph1617303 Khandale, S. P., Tapadiya, G. G., Rajput, S. P., et al. (2022). An effect of onion peel water on various plant disease and plant growth. International Journal of Scientific Development and Research (IJSDR), 7(1), 333–335. https://www.ijsdr.org/papers/IJSDR2201052.pdf Miller, E. (2024, May 3). Fish amino acid - Food for the garden. https://www.fishfulfuture.com/ Fishful Future. seafood-recipes/faa Nabayi, A

  generalrecommendationsevidence 5/5
  Keywords: https organic fertilizer impact plant chemical fertilizers eggshell journal international pepper food peel growth ijsdr

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