(MENTIK WANGI-MUTATED BADH2 GENE TRANSFER INTO NON-FRAGRANT RICE C.V. CIHERANG)

Djarot Sasongko Hami Seno1,*), Bambang Padmadi1), Dewi Praptiwi1), Sugihartati1), Taufiq1), Muhammad Taufan Fatahajudin1), Helmy Ramadhan Al Anshary1), Tri Joko Santoso2), Zainal Alim Mas’ud3)

ABSTRACT

Replacement of non-fragrant-native badh2 gene with mutated badh2 of fragrant rice is an alternative to engineer new fragrant rice varieties with good agronomic traits as those of non-fragrant. Fragrant gene (mutated badh2) of Mentik wangi donor was introgressed into non-fragrant Ciherang host through site-directed crossing. Mentik Wangi was crossed with Ciherang, and the progeny was further backcross until BC3F1. Bradbury marka-assisted PCR was used to select progeny in every cross and backcross generation. Ciherang, Mentik Wangi, and their cross/backcross showed different PCR profiles. The statues of badh2 gene (native/mutated), as well as alleles (homozygote/heterozygote) between samples were identified.  Mutated badh2-introgression was also observed within the selected heterozygote cross or backcross progenies (F1, BC1, BC2, and BC3), indicated successful transfer of mutated badh2 gene from donor to host.

Keywords: Backcross, Bradbury, fragrant, Mentik Wangi, badh2, site-directed crossing.

ABSTRAK

Penggantian badh2 utuh (native) padi nonaromatik dengan gen serupa yang termutasi dari varietas aromatik merupakan alternatif dalam pengembangan varietas aromatik baru nontransgenik dengan karakter agronomi sebaik padi nonaromatik. Pada penelitian ini dilakukan introgresi gen aroma (badh2 termutasi) dari Mentik Wangi (donor) ke varietas nonaromatik Ciherang (host) secara persilangan terarah (site-directed crossing). Mentik Wangi disilangkan dengan Ciherang, selanjutnya dibackross dengan Ciherang sampai BC3F1. Pada setiap generasi persilangan/backross dilakukan seleksi PCR berbantuan marka gen badh2. Hasil yang diperoleh menunjukkan perbedaan amplikon sampel Ciherang, Mentik Wangi dan persilangan/backross kedua varietas. Selain dapat dibedakan status gen (utuh/termutasi) dan alel (homozygot/heterozygot) badh2, juga teramati introgresi gen badh2 termutasi pada progeni hasil persilangan/backross (F1, BC1, BC2, dan BC3) yang terseleksi, menunjukkan keberhasilan transfer gen badh2 termutasi dari varietas donor ke host.

Kata kunci: Backcross, Bradbury, Mentik Wangi, Ciherang, badh2, site-directed crossing.