Xylanase adalah enzim dari kelas hidrolase EC 3. Xylanase juga memiliki banyak manfaat yang dapat diaplikasikan dalam industri , seperti sebagai agen pemutih dalam industri kertas, meningkatkan kandungan nutrisi pakan ternak , dan sebagai agen klarifikasi dalam pembuatan jus dan wine. Sebagian besar Xylanase diketahui optimum pada suhu di bawah 50 o C dan aktif pada pH asam atau netral. Dari Wikipedia bahasa Indonesia, ensiklopedia bebas.
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Plant parasitic nematodes cause great economic losses to agricultural crops worldwide. They along, with their hosts, are not isolated in the ecological system, but are strongly influenced by antagonists, parasites and pathogens.
Though pesticides appear to be the most economical and efficacious means of controlling plant pathogens, toxicological, environmental and sociological concerns have led to drastic reductions in the availability of efficient commercial nematicides.
These restrictions have forced farmers to look for an integral system that makes use of other means of disease control. Species of spiral nematodes, Helicotylenchus and Scutellonema, were among the most abundant plant parasitic nematodes of the mulberry plant. Eco-friendly control of the parasitic nematodes could be achieved by means of endoparasitic fungi like Hirsutella, Meria, Nematophthora and Nematoctonus , trapping fungi like Arthrobotrys and Duddingtonia or parasitic fungi like Paeceilomyces lilacinus.
During the course of this present work, Trichoderma Pers. The present study outlines the comparative efficacy of five Trichoderma species T.
The study also outlines the effect of Trichoderma viride Persoon on Scutellonema spp. Microbiology in Agriculture and Human Health. This imperative approach involves a mixture of agro-technical, biological, chemical and genetic breeding means of plant disease control [ 20 , 24 , 36 ]. Species of spiral nematodes, Helicotylenchus and Scutellonema , were among the most abundant plant parasitic nematodes of the mulberry plant.
Reductions in length and weight of shoot, number and weight of leaves, and number of leaf buds were the characteristic symptoms of the infection of spiral nematodes [ 10 ]. Rao and Swarup [ 26 ] found stunting of the plants and reduction in fresh and dry weights of both shoot and root system in sugarcane due to Helicotylenchus dihystera. Besides chemicals, various researchers suggested other control measures in view of the need to replace highly toxic and potentially polluting chemicals used to control plant parasitic nematodes and fungi with less dangerous chemicals, or preferably with biological control agents and botanicals [ 21 ].
The discovery of new biocontrol agents and the demonstration of their value in reducing disease incidence and severity has opened promising new avenues for practical applications in agriculture as well as for promoting environmental safety [ 8 ]. Considerable efforts have been made by many researchers for the management of different plant parasitic nematodes with the use of Trichoderma harzianum [ 1 - 5 , 23 , 28 , 33 ].
Eco-friendly control of the parasitic nematodes could be achieved by means of endoparasitic fungi like Hirsutella , Meria , Nematophthora and Nematoctonus , trapping fungi like Arthrobotrys and Duddingtonia or parasitic fungi like Paeceilomyces lilacinus. But there are problems in the culture of the fungi, such as unavailability of their host, and the generalist feeding nature of fungi that means they can become trapped on and digest beneficial as well as pest species of nematode.
The general approach has been to go to locations where nematodes have reached high densities, and extract parasitized individuals from the soil.
Then, the fungi were cultured and tested as parasites of the nematode pest. The mycoparasitic ability of Trichoderma sp. Windham et al. Combining T. Reduction of M. Trichoderma may also promote plant growth [ 19 ]. The fungi is characterized by rapidly growing colonies bearing tufted or postulate, repeatedly branched conidiophores with lageniform phialides and hyaline or green conidia borne in slimy heads.
They can be cultured and isolated from any type of soil. Considering the importance of the fungal genus containing species that have the potential for economic impact, the present study was carried out to determine the comparative efficacy of five Trichoderma species T.
The nematodes were observed under stereoscopic microscope and were counted using a Syracuse counting disc. The fungi were isolated through the serial soil dilution plate method [ 39 ]. Then, 10 g of oven dried fungi was added to a sterile Erlenmeyer flask with 90 ml sterile water, and the mixture was stirred with a magnetic stirrer for minutes.
A blender was used for blending the samples. While the suspension was in motion, 10 ml of solution was taken and added to 90 ml sterile water in a screw-cap flask or medicine bottle. It was shaken for one minute and 10 ml of the suspension was transferred to a 90 ml sterile water blank. The process was repeated until the desired dilution was obtained. Ten millilitres of soil solution was pipetted and mixed with 90 ml distilled water and marked to 10 From 10 -2 and 10 -3 test tubes about 5 ml solution was added to culture media contained in four petri dishes two of each and kept at laminar flow for days.
To facilitate uniform spreading of the suspension over Czapek Dox agar surface at pH 5. A water film on the freshly poured plates caused excessive spreading of organisms. A broth media was made by mixing together the substances excepting the agar. It was kept for 24 hours to dissolve the substances completely. Five to six drops of the broth were removed with a dropper into different autoclaved cavity blocks. Then, 0. Next, female Scutellonema spp. The cavity blocks containing the whole mixture were incubated at room temperature covered upside down by autoclaved petri dishes.
Uninoculated nematodes on the broth were also kept as control. Observation of the nematodes under stereoscopic binocular microscope to record their mobility and fungal infection was done at each hour interval.
Each treatment was replicated three times. The fungus attacked the nematodes though the production of conidia, sticky spores and mycelia, which on contact adhere to the cuticle and germinate, forming germ tubes that penetrated the nematodes.
Then, they extended their hyphae inside the nematodes after penetration of the cuticle by conidia formation. These hyphae multiplied profusely. They inactivated the parasitic nematodes and immobilized them due to production of certain antibiotics and compounds. Observations of the immobility and parasitism of the nematodes due to the fungi were made every 12 hours.
Each observation was replicated three times and the results are represented in tables 1 — Photographs with graphs of parasitism are also provided in figures 1 After 12 hours of inoculation, the fungus produced mycelium and conidia.
The highest immobility was found at hours of inoculation. The spores attached at the middle and anterior end of the body, and made the nematode immobile in the case of Scutellonema spp.
After 24 hours of inoculation, many mycelium were found attached to the entire body of the nematode, due to which the body of the nematode was deformed and became shrunken, killing many of the nematodes. Body constrictions of nematodes might be due to the sucking of body contents by the fungus. Fifty percent of Scutellonema spp. In the case of Helicotylenchus spp. The conidiophores of Trichoderma viride were less complicated; they formed aerial hyphae and coiled around the body of the nematode, producing smaller branches and ultimately forming a conifer-like branching system.
Effect of fungal inoculums Trichoderma viride on the activities of Scutellonema spp. Effect of fungal inoculums Trichoderma viride on the activities of Helicotylenchus spp. Infection and parasitism of the nematode occurred after 48 hours of inoculation. Many mycelia grew over the body of the nematode. The conidiophores were seen to be multiple-branched, forming loose tufts which arose in distinct and continuous ring-like zones. The main branches, mostly in groups of two or three, stood at right angles, and the length increased with the distance from the tip of the main branch, giving a conical or pyramidal appearance.
The body cuticle of the nematode was suppressed. The mycelia tip ran parallel to the nematode. There was rapid and excessive coiling on the target host. The mycelium coiled with its constricting networks of loops at the anterior region of the body and the head region, making constrictions that might be due to the sucking of body contents. After 96 hours of inoculation, there was complete immobilization of the nematodes.
In the case of Helicotylenchus , the highest percentage of infection and immobility occurred during 96 th hour of inoculation. Effect of fungal inoculums Trichoderma harzianum on the activities of Scutellonema spp. Effect of fungal inoculums Trichoderma harzianum on the activities of Helicotylenchus spp.
Infection started before 20 hours of inoculation. Hyphae of the fungus strain formed an appressorium-like structure in close contact with the nematode. They produced penetration holes in the cuticle of the nematode. The penetrated cuticle rapidly lost turgor and collapsed.
At contact with the nematode cuticle, the hyphae branched dichotomously at the tip. The hyphae were not observed to coil around the nematode cuticle, and instead grew along the cuticle. However, penetration was not evident. Despite the absence of visible penetration, the nematode cuticle lost turgor pressure, wrinkled and collapsed. Finally, both the cuticle and body content of the nematode completely disintegrated.
In the case of Helicotylenchus , the highest immobility was found at 60 hours of inoculation. Effect of fungal inoculums Trichoderma longibrachiatum on the activities of Scutellonema spp.
Effect of fungal inoculums Trichoderma longibrachiatum on the activities of Helicotylenchus spp. There was no effect during the first 12 hours of inoculation in the case of Helicotylenchus spp. After 24 hours of exposure, conidia attachment of the nematode was found. The conidia stuck towards the cephalic region and stylet of the nematode. Maximum immobility in the case of Scutellonema occurred at hours of nematode exposure to the fungus, while it occurred at hours of exposure in the case of Helicotylenchus sp.
At 48 hours of exposure, hyphae formation was found around the body of Helicotylenchus and at the anterior and posterior part of the body of Scutellonema spp. The hyphae penetrated towards the body cuticle of the nematode and sucked the body contents, affecting the nematode. Effect of fungal inoculum Trichoderma koningii on the activities of Scutellonema spp. Effect of fungal inoculum Trichoderma koningii on the activities of Helicotylenchus spp.
There was no effect on the nematode Scutellonema spp.
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