Fusarium oxysporum is the causal agent of damping-off disease. The fungus attacks seedlings of many plant species, including Acacia mangium. In order to effectively control the disease, detailed information on how the fungus infects seedlings of A. mangium and how the plant responds to the fungal infection is essentially needed. The objectives of this research were to investigate: (1) the infection process of F. oxysporumon seedlings of A. mangium, (2) the defence response of A. mangium seedling to infection by F. oxysporum. The fungal pathogen was identified, followed by performance of pathogenicity test. The infection process was followed by macroscopic observation as well as microscopic observation. The result indicated that fungal spore germination was observed at two-day post inoculation in planta. At four-daypost inoculation, hyphae of F. oxysporum had penetrated the collar root of A. mangium seedling via stomata aperture. In addition, fungal hyphae had grown intercellulary in to the vascular tissue. Correspondingly, hypersensitive response was also detected at the stomata aperture. However, this defence mechanism is not effective in stopping the fungus since F. oxysporum is a necrotropic pathogen. Moreover, accumulation of lignin, but not callose, was observed.
Sengon is a fast growing species that is cultivated widely in Indonesia. Lately, sengon is severely attacked by fungus Uromycladium tepperianum that causing gall rust disease. It is also known to attack various types of acacia. This study aims to determine the fungal infection process U. tepperianum on sengon leaves and the possibility of infection on Acacia mangium in the laboratory trial. Leave samples and fungal pathogen teliospores obtained from Cangkringan, Sleman, Yogyakarta. Several approach procedures conducted to achieve these objectives were: (1) identification of diseased trees, (2) collecting samples of diseased leaves, branches, twigs, and stems, and (3) artificial inoculation and investigating the infection process of U. tepperianum teliospores in the laboratory. The results showed that the process of infection in sengon started by teliospores germination and germ tube formation. Successive germ tube forming penetration pegs. In the plant tissue, the penetration peg formed hypha and further developed into intracellular and intercellular hyphae. The artificial inoculation on A. mangium leaf surface showed few spores can germinate. However, none of them managed to penetrate. AbstrakSengon merupakan tanaman cepat tumbuh yang dibudidayakan di Indonesia. Namun, akhir-akhir ini banyak sengon yang menderita penyakit karat tumor sangat parah. Penyakit ini disebabkan oleh jamur Uromycladium tepperianum, juga diketahui menyerang berbagai jenis tanaman akasia. Penelitian ini bertujuan mengetahui proses infeksi jamur U. tepperianum pada daun sengon dan kemungkinan infeksinya pada Acacia mangium di laboratorium. Sampel dan teliospora jamur patogen didapatkan dari Cangkringan, Sleman, Yogyakarta. Beberapa pendekatan yang digunakan untuk mencapai tujuan tersebut adalah: (1) identifikasi pohon yang sakit, (2) pengumpulan contoh berupa daun, cabang, ranting, dan batang yang sakit, serta (3) inokulasi buatan dan proses infeksi U. tepperianum di laboratorium menggunakan teliospora U. tepperianum. Hasil penelitian menunjukkan bahwa proses infeksi pada tanaman sengon diawali dengan perkecambahan teliospora dan pembentukan buluh kecambah. Buluh kecambah selanjutnya membentuk pasak penetrasi. Di dalam jaringan tanaman, pasak penetrasi membentuk hifa dan berkembang menjadi hifa intraseluler dan interseluler. Hasil uji inokulasi buatan pada permukaan daun A. mangium menunjukkan sebagian kecil spora dapat berkecambah. Namun, tidak ada yang berhasil melakukan penetrasi.
Pinus merkusii or tusam is an original Indonesian plant and it is naturally distributed in Aceh and North Sumatra. Damping-off disease is the main problem in its nurseries. Fusarium subglutinans is one of the leading causes of damping-off disease. The knowledge of fungal infections process of tusam seedlings is essential to control dampingoff disease effectively.The aim of this research is to understand (1) infection process of F. subglutinans in tusam seedlings and the defence response of seedlings against the infection of F. subglutinans. The methods used in this research were (1) identification of fungal pathogens that causing the disease, (2) pathogenicity test of F. subglutinans, (3) detection the accumulation of lignin, accumulation of callose and hypersensitive reactions by staining of seedling tissue using phloroglucinol, aniline blue and lactophenol trypan blue.The results of this study revealed that spores germination occurred in two days after inoculation. Direct penetration through cell wall and stomata was observed on the third day after inoculation. There was hypersensitive reaction in stomata. Accumulation of callose and lignin appeared on the third day after inoculation. However, defence response of seedlings was not effective, as F. subglutinans is a necrotroph fungus.
The diesel engine lifespan increasing in marine operation will decrease their perfomance. Some problems will occur, there are hard starting, bad exhaust gas colour and bad power output, suddenly engine stop and hard to start back. There fore any diesel engine training is needed to guard engine perfome. The KKM (Ketua Kamar Mesin= engine room head) training for maintaining their ability to serve diesel engine properly is necesary. Their ability have came from their friend or autodidact. The 25 fishingman ships were burning at Blora quay last several mounths prove of the lack of their ability. Thre are some rutine maintenances sould be done; every 8 hours Radiator water, diesel fuel and lubricantion oil are controlled, every week (150 hours) air screen cleaning, every two weeks (250 hours) oil lubricant replacement. Every month (500 hours) readjust fuel valve, every 1000 hours oil lubricant replacement and garvernor funtion checking, every 1500 hours inlet manifold cleaning and exhaust sistem, every 3000 fuel tank cleaning and to overhaul also replacement worn out spare parts, every 6000 hours cylinder head take apart and carbonation, and every 12000 hours general over haul and replacement worn out spare part.
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