ANALISIS KERAGAMAN MUTAN CABAI MERAH KERITING (Capsicum annuum L.) GALUR INDRAPURA TAHAN SALINITAS

Abstract

Cekaman salinitas merupakan salah satu kendala utama dalam budidaya cabai merah keriting di lahan marginal karena dapat menurunkan pertumbuhan dan produktivitas tanaman. Penelitian ini bertujuan menganalisis keragaman morfologi dan genetik mutan cabai merah keriting galur Indrapura hasil induksi mutasi sinar gamma dosis LD25 pada kondisi salinitas 5.000 ppm NaCl, serta menyeleksi genotipe terbaik menggunakan Multi-Variate Selection Index (MVSI). Sebanyak 600 benih mutan disemai dengan daya berkecambah sebesar 68,5%, kemudian dipilih 16 genotipe terbaik berdasarkan keragaan morfologi untuk dianalisis lebih lanjut. Karakter morfologi diamati menggunakan 36 karakter kualitatif dan 11 karakter kuantitatif. Analisis genetik dilakukan menggunakan enam primer start codon targeted (SCoT), sedangkan seleksi genotipe dilakukan menggunakan MVSI. Hasil penelitian menunjukkan enam karakter kualitatif bersifat polimorfik, sedangkan karakter jumlah buah memiliki koefisien keragaman tertinggi sebesar 52,31%. Analisis SCoT menghasilkan 58 pita DNA dengan 57 pita polimorfik (98,28%) dan mengelompokkan genotipe ke dalam tiga klaster utama. Analisis MVSI menunjukkan Genotipe 9 memiliki nilai indeks tertinggi (0,71), diikuti Genotipe 1 dan Genotipe 11 (0,60). Ketiga genotipe tersebut berpotensi dikembangkan sebagai galur harapan cabai merah keriting toleran salinitas dan berdaya hasil tinggi.

Salinity stress is one of the major constraints in curly red chili cultivation on marginal lands because it can reduce plant growth and productivity. This study aimed to analyze the morphological and genetic diversity of curly red chili mutants of the Indrapura line induced by gamma irradiation at the LD25 dose under salinity conditions of 5,000 ppm NaCl, and to select the best genotypes using the Multi-Variate Selection Index (MVSI). A total of 600 mutant seeds were sown, with a germination rate of 68,5%, after which 16 best genotypes were selected based on morphological performance for further analysis. Morphological traits were evaluated using 36 qualitative and 11 quantitative traits. Genetic analysis was conducted using six Start Codon Targeted (SCoT) primers, while genotype selection was performed using MVSI. The results showed that six qualitative traits were polymorphic, while the number of fruits had the highest coefficient of variation (52,31%). SCoT analysis produced 58 DNA bands, of which 57 were polymorphic (98,28%), and grouped the genotypes into three main clusters. MVSI analysis showed that Genotype 9 had the highest index value (0,71), followed by Genotypes 1 and 11 (0,60). These three genotypes have potential for further development as promising curly red chili lines with salinity tolerance and high yield potential.