Electronic Theses and Dissertation

Bawang merah (Allium ascalonicum) merupakan salah satu jenis tanaman hortikultura yang tergolong sayuran rempah yang dimanfaatkan sebagai bumbu dapur dan memiliki senyawa-senyawa kimia yang memiliki manfaat bagi kesehatan manusia. Bawang merah termasuk salah satu komoditas pertanian yang memiliki nilai ekonomis yang tinggi serta dibutuhkan setiap harinya oleh masyarakat. Beberapa penyakit yang disebabkan oleh cendawan dan umum dijumpai pada tanaman bawang merah diantaranya bercak ungu (Alternaria porri), moler (Fusarium oxysporum), busuk daun atau antraknosa (Colletotrichum gloeosporioides), mati pucuk (Phytophthora porri), embun bulu (Peronospora destructor), dan busuk umbi (Aspergillus niger). Penelitian ini bertujuan untuk mengidentifikasi peyebab penyakit layu dan karakterisasi gejala penyakit layu pada tanaman bawang merah (Allium ascalonicum) di Desa Dayah Sukon, Kecamatan Peukan Baro, Kabupaten Pidie.
Penelitian ini termasuk jenis kualitatif dengan pendekatan eksploratif. Pengambilan tanaman sampel dilakukan secara purposive random sampling yang dapat mewakili populasi serangan patogen. Sampel tanaman dan tanah diambil adalah tanaman yang menunjukkan gejala penyakit layu yang ditemukan di pertanaman bawang merah dengan pengambilan sampel tanaman secara acak. Dilakukan isolasi cendawan patogen pada sampel tanaman dan tanah, kemudian dilakukan karakterisasi morfologi cendawan patogen. Uji patogenisitas cendawan patogen pada bibit tanaman bawang merah untuk karakterisasi gejala penyakit pada bibit tanaman bawang merah. Parameter pada penelitian ini yaitu karakter makroskopis cendawan patogen, karakter mikroskopis cendawan patogen dan karakter gejala penyakit pada bibit tanaman bawang merah.
Hasil penelitian menunjukkan bahwa tanaman bawang merah yang terserang cendawan patogen menunjukkan gejala berupa tanaman layu dan kerdil, daun meliuk berwarna hijau kekuningan dan mengalami kekeringan yang tampak dari ujung daun. Pada serangan lanjut tanaman menjadi mati dan di bagian pangkal umbi, umbi dan akar membusuk dan terdapat miselia berwarna putih. Hasil karakterisasi dan identifikasi secara morfologi terhadap jenis cendawan yang menginfeksi bawang merah (Allium ascolanicum) di Desa Dayah Sukon, Kecamatan Peukan Baro, Kabupaten Pidie diperoleh tiga genus cendawan yaitu genus Fusarium spp. sebanyak 13 isolat, Aspergillus sp. sebanyak 5 isolat dan Colletotrichum sp. sebanyak 4 isolat. Fusarium spp. merupakan cendawan patogen yang dominan telah berhasil diisolasi sebanyak 13 isolat dengan 3 spesies Fusarium yang berbeda dan penyebab utama layu pada tanaman bawang merah (Allium ascalonicum). Pada uji patogenisitas ketiga cendawan patogen (Fusarium spp., Aspergillus sp., dan Colletotrichum sp.) menunjukkan gejala penyakit yang berbeda-beda dan gejala penyakit yang ditunjukkan pada uji patogenisitas sama dengan gejala penyakit yang ditemukan pada lahan pertanaman bawang merah.

Shallots (Allium ascalonicum) are one type of horticultural plant classified as spice vegetables that are used as kitchen spices and have chemical compounds that have benefits for human health. Shallots are one of the agricultural commodities that have high economic value and are needed every day by the community. Some diseases caused by fungi and commonly found in shallot plants include purple spot (Alternaria porri), moler (Fusarium oxysporum), leaf rot or anthracnose (Colletotrichum gloeosporioides), shoot death (Phytophthora porri), feather dew (Peronospora destructor), and bulb rot (Aspergillus niger). This study aims to identify the causes of wilt disease and characterize the symptoms of wilt disease in shallot plants (Allium ascalonicum) in Dayah Sukon Village, Peukan Baro District, Pidie Regency. This research is a qualitative type with an exploratory approach. Sampling plants is done by purposive random sampling that can represent the population of pathogen attacks. Plant and soil samples were taken from plants that showed symptoms of wilt disease found in shallot plantations with random sampling of plants. Pathogenic fungi isolation was carried out on plant and soil samples, then morphological characterization of pathogenic fungi was carried out. Pathogenicity test of pathogenic fungi on shallot seedlings to characterize disease symptoms in shallot seedlings. The parameters in this study are the macroscopic character of pathogenic fungi, the microscopic character of pathogenic fungi and the character of disease symptoms in shallot plant seedlings. The results showed that shallot plants attacked by pathogenic fungi showed symptoms in the form of wilted and stunted plants, yellowish-green twisted leaves and drought that appeared from the tips of the leaves. In advanced attacks the plants die and at the base of the bulbs, bulbs and roots rot and there are white mycelia. The results of morphological characterization and identification of the types of fungi that infect shallots (Allium ascolanicum) in Dayah Sukon Village, Peukan Baro District, Pidie Regency obtained three genus of fungi namely the genus Fusarium spp. as many as 13 isolates, Aspergillus sp. as many as 5 isolates and Colletotrichum sp. as many as 4 isolates. Fusarium spp. is the dominant pathogenic fungus that has been successfully isolated as many as 13 isolates with 3 different Fusarium species and the main cause of wilt in shallot plants (Allium ascalonicum). In the pathogenicity test, the three pathogenic fungi (Fusarium spp., Aspergillus sp., and Colletotrichum sp.) showed different disease symptoms and the disease symptoms shown in the pathogenicity test were the same as the disease symptoms found in shallot fields.