Electronic Theses and Dissertation

Pemanfaatan lahan marginal seperti lahan tegalan merupakan salah satu strategi untuk meningkatkan ketersediaan pangan. namun, kondisi suboptimal kekeringan menuntut penggunaan varietas padi yang adaptif. provinsi aceh memiliki plasma nutfah padi lokal yang berpotensi adaptif terhadap kondisi tersebut, salah satunya adalah tinggong. namun, tinggong memiliki kelemahan, seperti umur panen yang relatif panjang dan tinggi tanaman yang berlebihan, sehingga diperlukan perbaikan terhadap karakter tersebut. upaya perbaikan dilakukan melalui persilangan dengan galur irbb27. sejumlah galur hasil persilangan telah menunjukkan umur panen yang lebih cepat dan tanaman yang lebih pendek pada kondisi optimal. namun, evaluasi terhadap galur-galur tersebut di lingkungan suboptimal, khususnya lahan tegalan yang rentan terhadap kekeringan, belum dilakukan. oleh karena itu, penelitian ini bertujuan untuk mengevaluasi pertumbuhan dan produktivitas galur padi hasil persilangan tinggong dengan irbb27 pada generasi bc4f4 dan bc4f5, serta menganalisis hubungan antara karakter pertumbuhan dan potensi hasil. penelitian dilaksanakan di kebun percobaan rumah kasa, universitas syiah kuala, dengan ketinggian 5 mdpl. tahap bc4f4 dilaksanakan pada november 2023 hingga april 2024 menggunakan 7 galur, sedangkan tahap bc₄f₅ pada agustus 2024 hingga februari 2025 menggunakan 5 galur dan varietas pembanding ciherang. rancangan percobaan menggunakan rak non faktorial dengan 3 ulangan dan uji lanjut bnj pada taraf 5%. hasil menunjukkan bahwa galur t35.7.3.1.2 dan t38.1.4.4.11 memiliki pertumbuhan yang konsisten dan unggul di lahan tegalan. pada tahap bc₄f₄, tinggi tanaman berkisar 110,47 – 139,96 cm, jumlah anakan umur 8 mst 8,94 - 10,44, dan umur panen 122 - 127 hss. pada bc₄f₅, tinggi tanaman 101,25 – 119,17 cm, jumlah anakan 8,83 – 12,24, dan umur panen 119,67 - 127 hss. varietas ciherang memiliki tinggi 101,97 cm, jumlah anakan 9,78, dan umur panen 117,33 hss. produktivitas galur pada bc₄f₄ berkisar antara 5,81 – 9,93 ton ha⁻¹, sedangkan pada bc₄f₅ 3,12 – 5,37 ton ha-1. varietas ciherang menghasilkan 3,56 ton ha⁻¹. galur t35.7.5.13.5, t36.10.3.19.1, dan t38.1.4.4.11 menunjukkan produktivitas yang tinggi dan stabil pada kedua tahap. analisis korelasi menunjukkan potensi hasil memiliki hubungan sangat signifikan dengan jumlah anakan umur 8 mst (r = 0,93) dan jumlah malai (r = 0,96), yang menjadi indikator utama dalam seleksi galur unggul di lahan tegalan.

The utilization of marginal land such as dry fields is one strategy to increase food availability. However, suboptimal drought conditions require the use of adaptive rice varieties. The province of Aceh has local rice germplasm that has the potential to adapt to these conditions, one of which is Tinggong. However, Tinggong has weaknesses, such as a relatively long harvest period and excessive plant height, so improvements to these characteristics are needed. Improvement efforts were carried out through crossbreeding with the IRBB27 variety. Several crossbred varieties have shown faster harvest periods and shorter plants under optimal conditions. However, evaluations of these lines in suboptimal environments, particularly drought-prone upland fields, have not been conducted. Therefore, this study aims to evaluate the growth and productivity of rice lines resulting from the crossbreeding of Tinggong with IRBB27 at the BC4F4 and BC4F5 generations, as well as to analyze the relationship between growth characteristics and yield potential. The study was conducted at the Experimental Farm, Syiah Kuala University, at an elevation of 5 m above sea level. The BC4F4 stage was carried out from November 2023 to April 2024 using 7 lines, while the BC₄F₅ stage was conducted from August 2024 to February 2025 using 5 lines and the Ciherang variety as a control. The experimental design used a non-factorial RAK with 3 replications and a BNJ post-hoc test at the 5% level. The results showed that the T35.7.3.1.2 and T38.1.4.4.11 lines exhibited consistent and superior growth in upland fields. At the BC₄F₄ stage, plant height ranged from 110.47 to 139.96 cm, the number of tillers at 8 MST was 8.94 to 10.44, and the harvest age was 122 to 127 HSS. At the BC₄F₅ stage, plant height ranged from 101.25 to 119.17 cm, the number of tillers was 8.83 to 12.24, and the harvest age was 119.67 to 127 HSS. The Ciherang variety has a height of 101.97 cm, a number of tillers of 9.78, and a harvest age of 117.33 HSS. Productivity of the lines in BC₄F₄ ranges from 5.81 to 9.93 tons ha⁻¹, while in BC₄F₅ it ranges from 3.12 to 5.37 tons ha⁻¹. The Ciherang variety produced 3.56 tons ha⁻¹. The T35.7.5.13.5, T36.10.3.19.1, and T38.1.4.4.11 lines showed high and stable productivity in both stages. Correlation analysis showed that yield potential had a highly significant relationship with the number of tillers at 8 MST (r = 0.93) and the number of panicles (r = 0.96), which are the main indicators in the selection of superior lines in upland fields.