Electronic Theses and Dissertation

Produksi padi Indonesia mengalami penurunan, sehingga diperlukan varietas baru yang berdaya hasil tinggi dan tahan cekaman lingkungan. Tinggong memiliki keunggulan seperti ketahanan terhadap kekeringan dan cita rasa nasi yang baik, tetapi memiliki kelemahan yaitu tinggi tanaman yang terlampau tinggi yang dapat menyebabkan mudah rebah, umur yang dalam dan rentan terhadap penyakit. Swarna memiliki sifat genjah, berbatang pendek, dan tahan rendaman. Penelitian ini bertujuan untuk mengetahui performansi agronomi, potensi hasil, keragaman genetik, dan korelasi antar peubah galur padi BC4F2 hasil persilangan antara padi lokal Tinggong dan varietas unggul Swarna. Penelitian ini dilaksanakan di Kebun Percobaan Fakultas Pertanian dan Laboratorium Genetika dan Pemuliaan Tanaman dan Laboratorium Ilmu dan Teknologi Benih. Universitas Syiah Kuala mulai Agustus 2024 hingga Februari 2025. Penelitian ini menggunakan Rancangan Acak Kelompok dengan delapan galur BC4F2 turunan Tinggong/Swarna dan satu tetua pembanding, serta 4 ulangan sehingga diperoleh 36 unit percobaan. Hasil penelitian menunjukkan bahwa galur T41.9.21.9 dan T41.10.1.7 memiliki performansi agronomi yang lebih baik dibanding galur lainnya, seperti tinggi tanaman, jumlah anakan dengan panjang malai yang optimal. Galur T41.8.8.6 juga menunjukkan potensi hasil tertinggi, yaitu mencapai 9,69 ton ha-1. Nilai heritabilitas pada semua sifat yang diamati tergolong tinggi (0,85–1,00), variasi suatu sifat lebih dipengaruhi oleh faktor genetik dibandingkan lingkungan. Galur G2, G3, G5 dan G6 prospektif untuk dikembangkan lebih lanjut sebagai calon varietas unggul. Peneliti menyarankan agar dilakukan penelitian lanjutan yang melibatkan analisis molekuler terhadap gen sd-1 (pendek) dan sub-1 (tahan rendaman) pada galur-galur prospektif tersebut.
Kata kunci: Padi Tinggong, Swarna, galur BC4F2, agronomi, potensi hasil, keragaman genetik.

Rice production in Indonesia has declined, necessitating the development of new varieties with high yield potential and tolerance to environmental stresses. The local rice variety Tinggong possesses advantages such as drought tolerance and good eating quality; however, it has several weaknesses, including excessive plant height that leads to lodging, late maturity, and susceptibility to diseases. On the other hand, the improved variety Swarna is characterized by early maturity, short stature, and submergence tolerance. This research aimed to evaluate the agronomic performance, yield potential, genetic variability, and correlation among traits in BC4F2 rice lines derived from a cross between Tinggong and Swarna. The research was conducted at the Experimental Field of the Faculty of Agriculture, as well as at the Genetics and Plant Breeding Laboratory and the Seed Science and Technology Laboratory, Syiah Kuala University, from August 2024 to February 2025. The experiment used a Randomized Complete Block Design (RCBD) consisting of eight BC4F2 lines derived from Tinggong/Swarna crosses and one parental check, with four replications, resulting in a total of 36 experimental units. The results showed that lines T41.9.21.9 and T41.10.1.7 exhibited superior agronomic performance compared to the other lines, particularly in plant height, number of tillers, and optimal panicle length. Line T41.8.8.6 also demonstrated the highest yield potential, reaching 9.69 tons ha⁻¹. The heritability values for all observed traits were high (0.85–1.00), indicating that genetic factors had a greater influence than environmental factors on trait variation. Lines G2, G3, G5, and G6 were identified as promising candidates for further development as potential superior varieties. The researchers recommend further studies involving molecular analysis of the sd-1 (semi-dwarf) and sub-1 (submergence tolerance) genes in these promising lines. Key words: Tinggong rice, Swarna, BC4F2 line, agronomy, yield potential, genetic diversity.