Electronic Theses and Dissertation

Kedelai (Glycine max (L.) Merrill) merupakan salah satu sumber protein nabati masyarakat Indonesia yang produksinya masih rendah karena berkurangnya lahan yang subur akibat dari penggunaan pupuk anorganik secara terus menerus. Sifat fisika dan kimia pada tanah Entisol kurang baik untuk pertumbuhan tanaman dikarenakan unsur hara yang sedikit sehingga tidak optimalnya pertumbuhan tanaman. Sehingga perlu dilakukan perbaikan sifat fisik dan kimia Entisol dengan memberikan amelioran. Tujuan dari penelitian ini untuk mengetahui perubahan sifat fisika dan kimia tanah Entisol akibat pemberian amelioran terhadap pertumbuhan dan hasil tanaman kedelai (Glycine max (L.) Merrill).
Penelitian ini berlangsung dari Juni 2024 sampai dengan November 2024. Penelitian ini menggunakan rancangan acak kelompok (RAK) non faktorial dengan tujuh perlakuan dan tiga kali ulangan sehingga diperoleh 21 unit percobaan. Jenis perlakuan yaitu A0 = tanpa perlakuan, A1 = kompos jerami padi 10 ton ha-1, A2 = kompos jerami padi 20 ton ha-1, A3 = biochar sekam padi 4 ton ha-1, A4 = biochar sekam padi 8 ton ha-1, A5 = kompos jerami padi 10 ton ha-1 + biochar sekam padi 4 ton ha-1, A6 = kompos jerami padi 20 ton ha-1 + biochar sekam padi 8 ton ha-1.
Pemberian amelioran terhadap tinggi tanaman 2 MST perlakuan A3, A4 dan A6 berbeda nyata terhadap A1, dan tidak berbeda nyata dengan A2 dan A5. Tinggi tanaman 4 MST perlakuan A5 berbeda nyata dengan A0 juga A6, dan tidak berbeda nyata dengan A1, A2, A3, dan A4. Tinggi tanaman 6 MST menunjukkan hasil yang tidak berbeda nyata pada semua perlakuan. Jumlah cabang 2 MST perlakuan A5 berbeda nyata dengan A0, A1, dan A6, namun tidak berbeda nyata dengan A2, A3, dan A4. Jumlah cabang 4 dan 6 MST perlakuan A2, A3, A4, dan A5 berbeda nyata dengan A0 dan tidak berbeda nyata dengan A1, dan A6. Umur keluarnya bunga menunjukkan hasil yang tidak berbeda nyata pada setiap perlakuan. Hasil tanaman yaitu jumlah polong, perlakuan A2 dan A3 berbeda nyata dengan A0, dan tidak berbeda nyata dengan A1, A4, A5, dan A6. Bobot 100 biji perlakuan A3 dan A4 berbeda nyata dengan A0 dan A6. Berat berangkasan basah perlakuan A1, A2, A3, A4, dan A5 berbeda nyata dengan A0, namun tidak berbeda nyata dengan A6. Berat berangkasan kering perlakuan A3 berbeda nyata dengan A0 dan A1, namun tidak berbeda nyata dengan A4 dan A5, perlakuan A1 tidak berbeda nyata dengan A2, A4, dan A6. Pada sifat fisika tanah yaitu water holding capacity, kadar air pF 2,5 dan 4,2 juga pori air tersedia, juga terhadap sifat kimia tanah yaitu pH, C-organik, N-total, dan K,dd menunjukkan hasil yang tidak berbeda nyata pada semua perlakuan, namun pada P-tersedia perlakuan A6 berbeda nyata dengan A4, dan tidak berbeda nyata dengan A2, perlakuan A4 tidak berbeda nyata dengan A0.
Berdasarkan penelitian ini dapat disimpulkan bahwa pemberian amelioran mampu memberikan pengaruh terhadap pertumbuhan dan hasil tanaman kedelai (Glycine max (L.) Merrill), namun tidak memberikan pengaruh terhadap umur keluarnya bunga. Selain itu, pemberian amelioran tidak memberikan pengaruh terhadap sifat fisika dan kimia tanah Entisol, namun dapat meningkatkan nilai pH, P-tersedia, dan kapasitas menahan air (water holding capacity). Perlakuan terbaik terhadap perubahan sifat fisika dan kimia tanah Entisol serta pada pertumbuhan dan hasil tanaman kedelai (Glycine max (L.) Merrill) yaitu perlakuan A3 (biochar sekam padi 4 ton ha-1).

Soybean (Glycine max (L.) Merrill) is one of the sources of plant-based protein for the Indonesian community, but its production is still low due to the reduction of fertile land caused by the continuous use of inorganic fertilizers. The physical and chemical properties of Entisol soil are not favorable for plant growth because of the limited nutrients, resulting in suboptimal plant development. Therefore, it is necessary to improve the physical and chemical properties of Entisol soil by applying ameliorants. The purpose of this study was to determine the changes in the physical and chemical properties of Entisol soil due to the application of ameliorants on the growth and yield of soybean plants (Glycine max (L.) Merrill). This research was conducted from June 2024 to November 2024. The study used a non-factorial randomized block design (RBD) with seven treatments and three replications, resulting in 21 experimental units. The types of treatments were: A0 = no treatment, A1 = rice straw compost 10 tons ha-1, A2 = rice straw compost 20 tons ha-1, A3 = rice husk biochar 4 tons ha-1, A4 = rice husk biochar 8 tons ha-1, A5 = rice straw compost 10 tons ha-1 + rice husk biochar 4 tons ha-1, A6 = rice straw compost 20 tons ha-1 + rice husk biochar 8 tons ha-1. The application of ameliorants on plant height at 2 weeks after planting (WAP) showed that treatments A3, A4, and A6 were significantly different from A1, but not significantly different from A2 and A5. At 4 WAP, plant height in treatment A5 was significantly different from A0 and A6, but not significantly different from A1, A2, A3, and A4. At 6 WAP, plant height showed no significant differences among all treatments. The number of branches at 2 WAP in treatment A5 was significantly different from A0, A1, and A6, but not significantly different from A2, A3, and A4. The number of branches at 4 and 6 WAP in treatments A2, A3, A4, and A5 were significantly different from A0 and not significantly different from A1 and A6. The flowering age showed no significant differences among treatments. Regarding yield, the number of pods in treatments A2 and A3 was significantly different from A0, but not significantly different from A1, A4, A5, and A6. The weight of 100 seeds in treatments A3 and A4 was significantly different from A0 and A6. The fresh biomass weight in treatments A1, A2, A3, A4, and A5 was significantly different from A0, but not significantly different from A6. The dry biomass weight in treatment A3 was significantly different from A0 and A1, but not significantly different from A4 and A5; treatment A1 was not significantly different from A2, A4, and A6. For soil physical properties such as water holding capacity, water content at pF 2.5 and 4.2, and available water pores, as well as soil chemical properties including pH, organic carbon, total nitrogen, and exchangeable potassium (K), there were no significant differences among all treatments. However, for available phosphorus (P), treatment A6 was significantly different from A4 but not significantly different from A2; treatment A4 was not significantly different from A0. Based on this study, it can be concluded that the application of ameliorants can influence the growth and yield of soybean plants (Glycine max (L.) Merrill), but does not affect the flowering age. Furthermore, the application of ameliorants does not significantly affect the physical and chemical properties of Entisol soil, but can increase pH, available phosphorus, and water holding capacity. The best treatment for improving the physical and chemical properties of Entisol soil as well as the growth and yield of soybean plants was treatment A3 (rice husk biochar at 4 tons ha-1)