SELEKSI SEGREGAN TRANSGRESIF SORGUM GENERASI F4 BIOGUMA 1 AGRITAN X SAMURAI 2 UNTUK PRODUKSI BIOMASSA DAN NIRA

Abstract

Sorgum manis memiliki potensi besar sebagai sumber biomassa dan bahan baku bioetanol karena mampu menghasilkan biomassa dan kandungan gula yang tinggi. Penelitian ini bertujuan memperoleh informasi mengenai keragaman karakter agronomi, biomassa, kadar gula, dan volume nira serta mengidentifikasi segregan transgresif pada populasi F4 hasil persilangan Bioguma 1 Agritan × Samurai 2. Penelitian dilaksanakan di Kebun Percobaan Leuwikopo, Bogor, menggunakan 270 genotipe F4 dan dua varietas pembanding (Bioguma 1 Agritan dan Samurai 2). Analisis dilakukan terhadap karakter agronomi, biomassa, kadar gula, volume nira, keragaman genetik, heritabilitas, aksi gen, korelasi karakter, dan diferensial seleksi. Hasil penelitian menunjukkan bahwa populasi F4 memiliki keragaman fenotipik dan genetik yang luas dengan nilai heritabilitas tinggi pada sebagian besar karakter. Karakter biomassa dan potensi bioetanol umumnya dikendalikan oleh banyak gen dengan aksi gen aditif dan epistasis. Karakter total bobot segar memiliki heritabilitas tinggi dan korelasi positif sangat kuat dengan karakter biomassa serta potensi bioetanol lainnya sehingga efektif digunakan sebagai karakter seleksi. Seleksi langsung berdasarkan total bobot segar menghasilkan 49 genotipe terpilih yang diduga merupakan segregan transgresif. Genotipe B1S2-188, B1S2-204, B1S2-245, B1S2-185, dan B1S2-212 menunjukkan potensi tinggi untuk pengembangan sorgum biomassa dan bioetanol unggul.

Sweet sorghum has great potential as a biomass source and bioethanol feedstock due to its high biomass and sugar production. This study aimed to obtain information on the variability of agronomic characters, biomass, sugar content, and juice volume, as well as to identify transgressive segregants in the F4 population from the cross between Bioguma 1 Agritan × Samurai 2. The research was conducted at the Leuwikopo Experimental Field, Bogor, using 270 F4 genotypes and two check varieties (Bioguma 1 Agritan and Samurai 2). Analyses were carried out on agronomic traits, biomass, sugar content, juice volume, genetic variability, heritability, gene action, character correlation, and selection differential. The results showed that the F4 population had wide phenotypic and genetic variability with high heritability values for most characters. Biomass and bioethanol related traits were generally controlled by many genes with additive and epistatic gene actions. Total fresh weight exhibited high heritability and a very strong positive correlation with biomass and other bioethanol potential traits, making it an effective selection criterion. Direct selection based on total fresh weight produced 49 selected genotypes suspected as transgressive segregants. Genotypes B1S2-188, B1S2-204, B1S2-245, B1S2-185, and B1S2-212 showed high potential for the development of superior biomass and bioethanol sorghum varieties.