ANALISIS KETERPAUTAN GEN KETAHANAN TERHADAP POWDERY MILDEW PADA TANAMAN MELON (Cucumis melo L.) HASIL TEST CROSS DENGAN PENANDA SEQUENCE CHARACTERIZED AMPLIFIED REGION

MUHAMMAD TAUFIQ QURROHMAN, Dr. Budi Setiadi Daryono, M.Agr.Sc.

2012 | Tesis | S2 Biologi

Buah melon (Cucumis melo L.) merupakan salah satu jenis buah yang dikonsumsi masyarakat Indonesia dan memiliki nilai ekonomis tinggi sehingga banyak dibudidayakan. Salah satu kendala dalam budidaya tanaman melon adalah infeksi powdery mildew. Strategi pengendalian powdery mildew yang aman adalah dengan membudidayakan tanaman yang memiliki gen ketahanan terhadap powdery mildew. Gen tersebut dapat dideteksi dengan memanfaatan penanda molekular seperti Sequence Characterized Amplified Region (SCAR). Pada penelitian sebelumnya telah dihasilkan tanaman test cross PI 371795 yang tahan terhadap powdery mildew dan lebih unggul dibanding melon komersial. Akan tetapi, sifat ketahanan terhadap powdery mildew pada tanaman melon test cross PI 371795 ini masih mengalami segregasi. Penelitian ini bertujuan untuk mempelajari pola pewarisan gen ketahanan terhadap powdery mildew pada tanaman melon test cross PI 371795 dengan penanda Sequence Characterized Amplified Region (SCAR) dan mempelajari keterpautan penanda molekular SCAR dengan gen penyandi ketahanan tanaman melon test cross PI 371795 terhadap powdery mildew. Tanaman melon test cross PI 371795 ditanam di dalam greenhouse sebanyak 100 tanaman. Kemudian diambil sampel daunnya untuk ekstraksi dan amplifikasi DNA dengan penanda Sequence Characterized Amplified Region (SCAR). Hasil amplifikasi DNA dianalisis menggunakan tes Chi-square. Hasil tes Chi-square digunakan untuk melakukan analisis linkage map. Hasil penelitian menunjukkan bahwa pola pewarisan gen ketahanan tanaman melon test cross PI 371795 terhadap powdery mildew mengikuti pola pewarisan Mendel dengan rasio 1:1. Posisi penanda molekular SCAR yang terpaut dengan gen (Pm-I) penyandi ketahanan tanaman melon test cross PI 371795 terhadap powdery mildew (Pm-I) adalah 8,1 cM.

Melon (Cucumis melo L.) is one type of fruit that consumed by Indonesian and has high economic value so it is widely cultivated. One of the problems in melon cultivation is infection of powdery mildew. The safe strategy to control powdery mildew is by cultivating plants that have resistance gene against powdery mildew. This gene can be detected by using molecular marker such as Sequence Characterized Amplified Region (SCAR). In previous research, it was found that a test cross PI 371795 is resistant against powdery mildew and more superior than commercial melon. However, the powdery mildew resistance on melon test cross PI 371795 was still segregated. The objectives of this research were to study the inheritance pattern of resistance gene against powdery mildew on melon test cross PI 371795 with SCAR marker and to study the linkage of SCAR marker with gene that encode resistance against powdery mildew on test cross PI 371795. Test cross PI 371795 was planted in a greenhouse as much as 100 plants. Then the samples of the leaves were taken from each plants for DNA extraction and amplification with SCAR marker. Then the result of DNA amplification was analyzed by Chi-square test. The result of Chi-square test was used to do linkage map analysis. The result showed that the inheritance pattern of resistance gene against powdery mildew on melon test cross PI 371795 followed Mendelian pattern with 1:1 ratio. The position of SCAR marker linked to gene (Pm-I) that encode resistance against powdery mildew on test cross PI 371795 was 8,1 cM.

Kata Kunci : Cucumis melo L., powdery mildew, test cross, SCAR, linkage map