RESISTENSI Podosphaera xanthii PENYEBAB POWDERY MILDEW PADA TANAMAN MELON (Cucumis melo L.) TERHADAP FUNGISIDA AZOXYSTROBIN DAN PYRACLOSTROBIN

MUHAMMAD EVY PRASTIYANTO, Rina Sri Kasiamdari, S.Si., Ph.D.; Prof. Drs. Langkah Sembiring, M.Sc., Ph.D.

2014 | Tesis | S2 Biologi

Tujuan penelitian ini adalah mengetahui resistensi P. xanthii terhadap kelompok fungisida QoI (azoxystrobin dan pyraclostrobin) di Indonesia. Dua belas strain P. xanthii didapat dari melon yang terserang powdery mildew di daerah-daerah yang menjadi pusat budidaya melon di Jawa pada bulan Mei sampai Oktober 2011. Dua belas strain ini diuji resistensinya terhadap fungisida azoxystrobin dan pyraclostrobin dengan metode leaf disc. Dari kedua belas strain uji, tiga strain (strain Jamusan, Kulonprogo, dan Bimomartani) menunjukkan resistensi fenotipik terhadap azoxystrobin dan pyraclostrobin dengan kemampuan tumbuh pada konsentrasi ≥10ppm dan MIC ≥25ppm. Tiga strain mampu tumbuh pada fungisida azoxystrobin dengan konsentrasi 10 ppm dan MIC 25 ppm dengan EC50 dan RF sebesar: 8,2 ppm dan 10,7 untuk strain Jamusan; 10,7 ppm dan 14,0 strain Kulonprogo; 4,7 ppm dan 6,1 strain Bimomartani. Strain Jamusan dan Kulonprogo mampu tumbuh pada fungisida pyraclostrobin dengan konsentrasi masing-masing yaitu 25 ppm, sedangkan strain Bimomartani pada konsentrasi 100 ppm. Nilai MIC 50 ppm pada strain Jamusan dan Kulonprogo, pada strain Bimomartani MIC sebesar 250 ppm, EC50 dan RF sebesar; strain Jamusan 10,8 ppm dan 5,4; strain Kulonprogo 11,7 ppm dan 5,8; strain Bimomartani 84,5 ppm dan 42,0. Dapat disimpulkan bahwa terdapat variasi antar strain anggota spesies P. xanthii terhadap azoxystrobin dan pyraclostrobin..

The aim of this research was to determine the resistance of P. xanthii against group QoI fungicides (azoxystrobin and pyraclostrobin) in Indonesia. Twelve strains of P. xanthii obtained from infected melon powdery mildew in the area which became the center of melon cultivation in Java on May to October 2011. Twelve of these strains were tested resistance to the fungicide azoxystrobin and pyraclostrobin by leaf disc method. Based on the twelve strains tested, three strains (strains Jamusan, Kulonprogo, and Bimomartani) showed phenotypic resistance to azoxystrobin and pyraclostrobin with the ability to grow at concentrations ≥10 ppm and MIC ≥25 ppm. The three strains were able to grow on fungicide azoxystrobin with a concentrations of 10 ppm and 25 ppm with EC50 and RF for: strain Jamusan 8.2 ppm and 10.7; strains Kulonprogro 10.7 ppm and 14.0; strains Bimomartani 4.7 ppm and 6,1. Strains Jamusan and Kulonprogo were able to grow at a concentration of 25 ppm in the fungicide pyraclostrobin while Bimomartani strains was 100 ppm. MIC value of 50 ppm in Jamusan and Kulonprogro strain, the strain Bimomartani MIC of 250 ppm, and the EC50 for RF; strains Jamusan 10.8 ppm and 5.4; strains Kulonprogro 11.7 ppm and 5.8; strains Bimomartani 84.5 ppm and 42.0. It can be concluded that there is variation among strains of the member species P. xanthii against azoxystrobin and pyraclostrobin

Kata Kunci : Podosphaera xanthii, resistensi fungisida, azoxystrobin, pyraclostrobin