Electronic Theses and Dissertation

Penyakit blas yang disebabkan cendawan Pyricularia oryzae Cav. atau Pyricularia
grisea [sinonim Magnaporthe oryzae (Hebert) Barr] merupakan penyakit penting yang
menginfeksi tanaman padi. Kehilangan hasil produksi padi di Indonesia mencapai 50-
100%. P. oryzae dapat menyerang tanaman padi pada fase vegetatif dan generatif. Pada
fase vegetatif gejala penyakit blas dijumpai pada daun padi (leaf blast), sedangkan pada
fase generatif dijumpai pada bagian leher malai (neck blast), buku tanaman (node blast),
dan bulir padi. Salah satu metode pengendalian penyakit blas yang efektif adalah dengan
varietas tahan. Upaya untuk mendapatkan varietas tahan dapat dilakukan dengan cara
persilangan antar dua varietas yang berbeda. Persilangan mampu menghasilkan genotip
yang lebih baik dari tetuanya terutama dalam ketahanan terhadap penyakit tanaman.
Genotip padi turunan BC4F3 merupakan hasil persilangan padi lokal Aceh (Tinggong) dan
varietas introduksi (IRBB27). Genotip BC4F3 memiliki umur lebih pendek, jumlah anakan
lebih banyak, terdapat gen sd-1 (gen pemendekan batang), hasil produksi lebih tinggi serta
ketahanan terhadap patogen Xanthomonas oryzae pv. oryzae strain IV dan VIII.
Penelitian ini dilaksanakan di Laboratorium Ilmu Penyakit Tumbuhan dan Rumah
Kasa Fakultas Pertanian Universitas Syiah Kuala sejak bulan September 2023 sampai
Januari 2024. Penelitian ini menggunakan Rancangan Acak Lengkap (RAL) non Faktorial
dengan 7 perlakuan (T35.7.5.13.3, T35.7.5.23.11, T35.12.8.2.1, T36.10.3.10.6,
T36.10.3.19.1, T37.3.2.1.5 dan T38.1.4.4.11) setiap perlakuan diulang sebanyak 3 kali, dan
setiap perlakuan terdiri dari 4 unit sehingga terdapat 84 unit perlakuan. Peubah yang di
amati meliputi masa inkubasi penyakit (hari), insidensi penyakit (%), keparahan penyakit
(%), jumlah bercak bersporulasi dan tidak bersporulasi, tinggi tanaman maksimun (cm)
dan jumlah anakan maksimum (batang).
Hasil penelitian menunjukkan bahwa, perlakuan genotip turunan BC4F3 berpengaruh
sangat nyata terhadap masa inkubasi penyakit (hari), insidensi penyakit (%), keparahan
penyakit (%), bercak bersporulasi dan tidak bersporulasi dan tinggi tanaman serta tidak
berpengaruh terhadap jumlah anakan. Masa inkubasi tercepat terjadi pada genotip
T37.3.2.1.5 (1,58 HSI) sedangkan terlama terjadi pada genotip T35.10.3.19.1 (4,63 HSI).
Insidensi penyakit terendah terjadi pada genotip T35.10.3.19.1 sebesar 36,67% serta
tertinggi pada genotip T37.3.2.1.5 sebesar 78,33%. Keparahan penyakit blas terendah pada
genotip T35.10.3.19.1 sebesar 4,63% sedangkan tertinggi pada genotip T37.3.2.1.5 sebesar
41,30%. Jumlah bercak bersporulasi dan tidak bersporulasi terendah terjadi pada genotip
T35.10.3.19.1 sebesar 0,67 dan 4,33 sedangkan yang tertinggi pada genotip T37.3.2.1.5
sebesar 9,00 dan 33,67. Tinggi tanaman terendah pada genotip T37.3.2.1.5 dan tertinggi
pada genotip T35.10.3.19.1. Jumlah anakan terendah pada genotip T35.10.3.19.1 dan
tertinggi pada genotip T35.7.5.13.3. Dapat disimpulkan genotip padi turunan BC4F3
memiliki tingkat ketahanan yang berbeda terhadap serangan Pyricularia oryzae. Genotip
T36.10.3.19.1 tergolong tahan, genotip T36.10.3.10.6 tergolong agak tahan, genotip
T35.7.5.13.3, T35.7.5.23.11 dan T35.12.8.2.1 tergolong sedang, sedangkan genotip
T37.3.2.1.5 dan T38.1.4.4.11 tergolong agak rentan.

Blast disease caused by the fungus Pyricularia oryzae Cav. or Pyricularia grisea [synonym Magnaporthe oryzae (Hebert) Barr] is an important disease that infecting rice plants. Yield loss of rice production in Indonesia reaches 50-100%. P. oryzae can attack rice plants in the vegetative and generative phases. At vegetative phase, symptoms of blast disease are found on rice leaves (leaf blast), while in the generative phase it is found on the neck of the panicle (neck blast). generative phase is found on the neck of the panicle (neck blast), plant book (node blast),and rice grains. One of the effective methods of controlling blast disease is with resistant varieties. resistant varieties. Efforts to obtain resistant varieties can be done by crossing between two different varieties. Crosses are able to produce genotypes genotypes that are better than their parents, especially in resistance to plant diseases. The rice genotype BC4F3 is the result of crossing local Acehnese rice (Tinggong) and an introduced variety (IRBB27). introduced variety (IRBB27). The BC4F3 genotype has a shorter lifespan, a higher number of tillers, the presence of the sd-1 gene (IRBB27). number of tillers, sd-1 gene (stem shortening gene), higher yield and resistance to Xanthomonas pathogen. resistance to pathogen Xanthomonas oryzae pv. oryzae strains IV and VIII. This research was conducted in Plant Disease Laboratory and Gauze House, Faculty of Agriculture, Syiah Kuala University from September 2023 until September 2023. Gauze House, Faculty of Agriculture, Syiah Kuala University, from September 2023 to January 2024. January 2024. This research used a non-factorial Completely Randomized Design (CRD) with 7 treatments (T35.7.5.13.3, T35.7.5.23.11, T35.12.8.2.1, T36.10.3.10.6, T36.10.3.19.1, T37.3.2.1.5 and T38.1.4.4.11) each treatment was repeated 3 times, and each treatment consisted of 4 units so there were 84 treatment units. The variables observed observed included disease incubation period (days), disease incidence (%), disease severity (%), number of blotches (%), and number of blotches (%). (%), the number of sporulated and non-sporulated spots, maximum plant height (cm), and maximum number of tillers (stems) and maximum number of tillers (stems). The results showed that the treatment of BC4F3 genotypes had a very significant effect on the incubation period (days), disease incidence (%), and disease severity (%). very significant effect on disease incubation period (days), disease incidence (%), disease severity (%), speciated and non-speciated spots and plant height and did not affect plant height. disease severity (%), sporulated and non-sporulated spots and plant height and had no effect on the number of tillers. effect on the number of tillers. The fastest incubation period occurred in genotypesT37.3.2.1.5 (1.58 HSI) while the longest occurred in genotype T35.10.3.19.1 (4.63 HSI). The lowest disease incidence occurred in genotype T35.10.3.19.1 at 36.67% and the highest in genotype T37.3.2.1.5 at 78.33%. Blast disease severity was lowest in genotype T35.10.3.19.1 at 4.63% while the highest was in genotype T37.3.2.1.5 at 41.30%. 41,30%. The lowest number of sporulated and non-sporulated spots occurred in genotypesT35.10.3.19.1 at 0.67 and 4.33 while the highest was in genotype T37.3.2.1.5 by 9.00 and 33.67. The lowest plant height was in genotype T37.3.2.1.5 and the highest was in genotype T35.10.3.19.1. in genotype T35.10.3.19.1. Number of tillers was lowest in genotype T35.10.3.19.1 and the highest in genotype T35.7.5.13.3. It can be concluded that rice genotypes derived from BC4F3have different levels of resistance to Pyricularia oryzae attack. Genotype T36.10.3.19.1 was classified as resistant, genotype T36.10.3.10.6 was classified as moderately resistant, genotype T35.7.5.13.3, T35.7.5.23.11 and T35.12.8.2.1 were classified as medium, while genotypes T37.3.2.1.5 and T38.1.4.4.11 were classified as moderately susceptible