ABSTRAK
Berton Sianturi. 2015. Distribusi dan Karakterisasi Populasi Sintrong (Crassocephalum crepidioides. Benth) Gulma Resisten Parakuat pada Lahan Tanaman Jagung (Zea mays) di Kabupaten Dairi, dibimbing oleh Edison Purba, dan Lisnawita. Penelitian ini bertujuan untuk menentukan karakteristik, dan distribusi populasi sintrong (C.crepidiodes) yang resisten parakuat pada lahan tanaman jagung di Kabupaten Dairi. Kabupaten Dairi sebagai sumber benih gulma sintrong berada pada ketinggian 400 – 1700 meter di atas permukaan laut. Penapisan populasi sintrong dilakukan di Kecamatan Patumbak Kabupaten Deli Serdang. Penelitian ini dilaksanakan mulai bulan Mei 2013 sampai dengan Pebruari 2014. Percobaan ini dilakukan dalam dua tahap, yaitu tahap pertama penapisan populasi sintrong dengan parakuat pada dosis anjuran 304,5 gr.b.a/ha, dan tahap kedua menguji tingkat resistensi populasi sintrong dari hasil penapisan. Untuk menguji tingkat resistensi dari hasil penapisan, dipilih 3 (tiga) populasi yang memilki persentase hidup paling tinggi dan populasi yang sensitif sebagai kontrol. Percobaan tahap pertama menggunakan Rancangan Acak Kelompok (RAK) dengan tiga ulangan, tahap kedua dengan Rancangan Kelompok Lengkap Teracak (RKLT) dengan tiga ulangan. Penapisan dan uji tingkat resistensi populasi sintrong menggunakan herbisida berbahan aktif diklorida 280g/l setara dengan ion parakuat 203g/l. Perlakuan yang digunakan tahap kedua dengan dosis 0 gr/ha (P0), 76 gr.ba/ha (P1), 152 gr.ba/ha (P2), 304,5gr.ba/ha (P3), 609 gr.ba/ha (P4), 1218 gr.ba/ha (P5), 2436 gr.ba./ha (P6). Alat menyemprot digunakan knapsack sprayer elektrik dengan nozzle T-jet warna kuning dengan lebar semprot 0,5 m. Hasil penapisan dari 30 populasi sintrong, sebanyak 19 populasi (63,3%) termasuk kategori K2 dengan tingkat rata-rata mortalitas 24,82%, sedangkan 11 populasi (36,7%) termasuk kategori K3 dengan tingkat rata-rata mortalitasnya 5,12%. Rata-rata lama penggunaan parakuat oleh petani responden 17,4 tahun, dengan dosis 544,57gr.ba/ha, serta frekuensi 1,5 kali/periode tanam. Populasi sintrong resisten parakuat terdistribusi pada enam kecamatan di Kabupaten Dairi, resistensi terkecil 47,92% (C11) terdapat di Kecamatan Siempat Nempu Hulu, dan tertinggi 100,0% (C29, C30) terdapat di Tanah Pinem. Tingkat resistensi (R/S) populasi sintrong R-C25 dari Kecamatan Tiga Lingga, R-C27, dan R-30 dari Tanah Pinem berturut-turut adalah 12,3, dan 14,86 serta 24,83 kali lipat dibandingkan populasi sensitif. Rata-rata jumlah klorofil daun sintrong populasi sensitif berbeda nyata dengan populasi resisten.
Kata kunci: Crassocephalum crepidioides, Parakuat, Herbisida, Resisten
ABSTRACT
Berton Sianturi. 2015. The Distribution and the Characteristict of Crassocephalum crepidioides Benth Weed Resistan to Paraquat at Corn field (Zea mays) in Dairi District,”supervised by Edison Purba, and Lisnawita. The objective of the research was to determine the characteristics and the distribution of C.crepidioides which is resistant to paraquat in corn fields in Dairi District as the source of C, crepidioides at the altitude of 400 - 1700 meters above sea level. Its population was screened in Patumbak Subdistrict, Deli Serdang District. The research was conducted from May 2013 until February 2014. The experiment was conducted in two stages, in the first stage, its population was screnened with parakuat at the suggested dosage of 304.5 g.ai/ha and in the second stage its resistance level from the screening was tested. Three populations, which had the highest living percentage and the sensitive population as control, were selected to examine their resistance levels. The first experiment used Group Random Design and the second experiment used Complete Group Random Design with three replications respectively. The screening and the testing of the resistance levels of its population used herbicide with active dichloride iof 280g /l which was equivalent with paraquat ion of 203 g/l. Treatment in the second stage used dosage of 0 g.ai/ha (P0), 76 g.ia/ha (P1), 152 g.ai/ha (P2), 304,5g.ai/ha (P3), 609 g.ai/ha (P4), 1218 g.ai/ha (P5), 2436 g.ai. / ha (P6). Knapsack electric sprayer with yellow nozzle T-jet and spraying reach of 0.5 m was used. The results of the screening on 30 C.crepidioides showed that 19 populations (63.3%) were in K2 category at the average mortality level of 24.82% and while the 11 populations (36.7%) were in K3 category at the average mortality level of 5,12%. The average length oftimt in using paraquat by the respondents was 17.4 years, at dosage of 544,57g.ai/ha with the frequency of 1.5 times/planting period. The C. crepidioides resistant to paraquat was distributed in six subdistricts of Dairi District; the lowest resistance 47.92% (C11) was found in Siempat Nempu Hulu Subdistrict and the highest resistance 100.0% (C29, C30) was found Tanah Pinem. The resistance level (R/S) of C.crepidioides R-C25 was from Tiga Lingga Subdistrict, while R-C27, and R-C30 were from Tanah Pinem at 12.3, 14.86 and 24.83 times consecutively, compared with sensitive population. The average number of C.crepidioides chlorophyll leaves in sensitive population was significantly different from those in resistant population.
Keywords: Crassocephalum crepidioides, Paraquat,Herbicide, Resistance
