Mottle disease, caused by viral infection is one of the main disease in black pepper plants. Piper yellow mottle virus (PYMoV) and Cucumber mosaic virus (CMV) are recorded as the causal agent of mottle disease in several countries. Research was conducted at the Sukamulya Research Station, Sukabumi Regency, West Java, to observe disease incidence and identify the associated virus. Field observation and sampling was carried out on 50 black pepper plants, aged around 3-4 years. Virus detection was performed by PCR and reverse transcription (RT)-PCR using a primer pair that amplified the ORF III of PYMoV (AIB 104/AIB 105), and CMV coat protein (AIB 1/AIB 2), followed by sequencing and analysis of nucleotide sequences. Incidence and severity of mottle disease in Sukamulya reached 100% and 32.50%, respectively. Specific DNA target were successfully amplified, i.e. 400 bp and 650 bp for PYMoV and CMV, respectively. Phylogenetic analyses revealed that PYMoV isolate from Sukamulya is closely related with PYMoV isolates from India (DQ83623); while CMV isolate from Sukamulya is closely related with CMV isolates from Indonesian bananas (AB069971), and it is belonged to subgroup 1B, as did CMV from black pepper in India (AY545924).

Ganoderma philippii causes root-rot disease in a wide range of commercial perennial woody crops such as rubber and tropical acacias. In terms of productivity loss, the disease is considered as the most economically damaging disease of Acacia mangium. Many strategies to manage root rot have been developed and applied, including application of biological control which has focused on species and strains of the ascomycete genus Trichoderma. This research aimed to test the potential of a wood-rotting basidiomycete as a biocontrol agent for root rot caused by Ganoderma philippii. This basidiomycete was isolated from a Eucalyptus pellita stump in a coppicing trial in Riau province, central Sumatra. DNA sequence analysis indicated that this isolate is most likely a Phlebiopsis sp. In vitro tests and microscopic morphological description of mycelial interactions between the Phlebiopsis and G. philippii isolates showed a mycoparasitic reaction. This result offered an alternative potential fungal isolate for root-rot management in Indonesia as Phlebiopsis gigantea is already successfully used as a biocontrol agent for managing root rot caused by Heterobasidion annosum throughout pine forests in Europe and North America.

Ornamental roses worldwide harbor 10 Phragmidium species. Among these, P. americanum, P. fusiforrne, P. montivagum, P. mucronaturn, P. rosae-pimpinellifoliae, P. rosae-rugosae and P. tuberculatum are frequently reported; however, these species are morphologically similar and difficult to distinguish. For better circumscription and correct identification of the species, this study examined morphological features in urediniospores and teliospores of the seven Phragmidium species collected on ornamental rose cultivars and wild species. The results indicated that some host-specific groups could be well circumscribed by the morphological properties of urediniospores and teliospores. However, without the precise identification of hosts, these morphological properties were not effective key characters for the identification of the species.

Ginger is an economically important commodity of Indonesia. A diamond shape leaf spot disease has been reported in ginger cultivation areas. The aim of this study was to determine the causal agent of the disease. Two isolates were obtained by a single conidia isolation method on Pyricularia typical conidia, followed by propagation on a PDA medium. The conidial suspensions were sprayed onto leaf of white and red ginger types for pathogenicity test. The inoculated plants were placed at room temperature with 80%-90% air humidity for 48 hr, then put back in the green house. The fungal identity was determined based on its morphological characteristic and confirmed by molecular characterization through DNA extraction and amplification using ITS5 and ITS4 primers. The optimal growth temperature of the fungus was assayed by planting each isolate onto PDA medium, then incubated at 4 level temperatures. The same temperature levels was also tested on conidial germination, on WA medium. The artificial inoculation showed both isolates infected all types of ginger, but red ginger showed lower in disease severity. Morphologically, both isolates are corresponding to Pyricularia zingiberi. The fungus grows optimally between 25 °C and 31 °C. PCR analysis supported the morphological observation results.

ABSTRAKPenyakit kerdil yang disebabkan oleh Piper yellow mottle virus (PYMoV) dan Cucumber mosaic virus (CMV) merupakan salah satu penyakit penting pada tanaman lada di Indonesia. Keberadaan PYMoV tidak mudah dikenal karena di lapang infeksi kedua virus dapat terjadi pada satu tanaman. Deteksi PYMoV pada sampel tanaman lebih akurat perlu dicari dan teknik molekuler dianggap paling sesuai untuk saat ini. Tujuan penelitian ini adalah mendeteksi PYMoV pada tanaman lada secara polymerase chain reaction (PCR) menggunakan pasangan primer spesifik PYMoV-F dan PYMoV-R. Isolasi total DNA tanaman lada dilakukan menggunakan ATP genomic DNA mini kit. Deteksi PYMoV secara molekuler dilakukan dengan teknik PCR menggunakan pasangan primer spesifik PYMo-F dan PYMoV-R. Untuk mengecek spesifitas primer yang digunakan, dilakukan perunutan nukleotida pada produk PCR yang dihasilkan. Runutan nukleotida yang diperoleh selanjutnya dianalisis dengan program BioEdit Sequence Alignment Editor, Complementor, Translate dan BLAST. DNA total hasil isolasi memiliki kualitas yang baik terlihat dari terbentuknya pita DNA yang utuh pada gel elektroforesis. Teknik PCR yang dilakukan berhasil mendapatkan pita DNA berukuran sekitar 450 pb (pasang basa) sesuai dengan prediksi dari desain primer. DNA yang didapatkan memiliki runutan nukleotida sebanyak 450 nukleotida yang ditranslasikan menjadi 148 asam amino. Hasil analisis BLAST runutan nukleotida menunjukkan bahwa isolat yang terdeteksi merupakan PYMoV yang memiliki kemiripan runutan nukleotida sebesar 92% dengan PYMoV asal Vietnam. Primer PYMoV-F dan PYMoV-R dapat digunakan untuk mendeteksi PYMoV pada tanaman lada. Kata kunci: Deteksi virus, lada, PCR, PYMoV ABSTRACT Dwarf disease caused by Piper yellow mottle virus (PYMoV) and Cucumber mosaic virus (CMV) is one of the important diseases of black pepper in Indonesia. The PYMoV presence in the natural condition is difficult to be detected through conventional method since both the viruses often infect on a single plant. A more appropriate method to detect the PYMoV existence should be developed, and the recent progress of molecular techniques is a promising tools for detecting the presence of PYMoV in a black pepper accurately. The purpose of this study was to detect PYMoV on blackpepper by PCR using specific primer pairs PYMoV-F and PYMoV-R. Isolation of total DNA from black pepper leaf was performed using genomic DNA mini kit ATP. PYMoV molecular detection was performed by PCR using specific primer pairs of PYMoV-F and PYMoV-R