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Abstrak :
Penelitian bertujuan mengisolasi dan mengidentifikasi khamir phylloplane Broussonetia papyrifera asal Bandung (Dago Pojok), Garut (Tunggilis dan Sukadanu), dan Trowulan, menguji kemampuan khamir antagonis dari daun B. papyrifera asal Desa Sukadanu dan Desa Tunggilis, Garut, Jawa Barat yang berpotensi sebagai agens biokontrol terhadap kapang-kapang penyebab kebusukan pada buah tomat pascapanen serta mengetahui viabilitas khamir setelah dipreservasi pada suhu -80 oC. Sebanyak 2.543 isolat khamir diperoleh dari empat wilayah sampling menggunakan metode washing dan membrane filter method. Pemilihan 82 isolat khamir representatif berdasarkan kemiripan morfologi koloni. Identifikasi khamir dilakukan berdasarkan sequence pada daerah internal transcribed spacer regions ribosomal DNA. Hasil identifikasi menunjukkan bahwa isolat khamir tersebut terdiri atas 17 genera dan 32 spesies: sebanyak 11 genera termasuk ke dalam Ascomycota (Saccharomycetes dan Dothidiomycetes), dan sebanyak enam genera termasuk Basidiomycota (Tremellomycetes, Microbotryomycetes, dan Ustilaginomycetes). Tiga kapang representatif berdasarkan hasil isolasi dari buah tomat dan uji patogenitas dapat menyebabkan kebusukan pada buah tomat pascapanen, yaitu Alternaria alternata, Lasiodiplodia theobromae, dan Syncephalastrum racemosum. Enam spesies khamir antagonis dapat menghambat pertumbuhan dan sporulasi A. alternata, L. theobromae, dan Syn. racemosum yaitu Candida saopaulonensis UICC Y-492, Candida pseudojiufengensis UICC Y-475, Debaryomyces hansenii UICC Y-488, Geotrichum candidum UICC Y-495, Hyphopichia burtonii UICC Y-496, dan Rhodotorula mucilaginosa UICC Y-476. Khamir antagonis dari B. papyrifera memiliki kemampuan menghambat pertumbuhan kapang A. alternata dan L. theobromae penyebab kebusukan pada buah tomat pada suhu 26--28oC selama 15 hari inkubasi. Khamir C. pseudojiufengensis UICC Y-475 dapat menghambat pertumbuhan kapang dan gejala kebusukan pada buah tomat (100%) disebabkan kapang A. alternata. Khamir C. saopoulenensis UICC Y-492 dan Rh. mucilaginosa UICC Y-513 dapat menghambat pertumbuhan kapang dan gejala kebusukan pada buah tomat (67%) yang disebabkan L. theobromae. Hasil pengujian viabilitas khamir setelah dipreservasi pada suhu -80oC selama 180 hari menunjukkan metode tersebut baik untuk preservasi jangka panjang empat spesies khamir potensial agens biokontrol pada buah tomat, yaitu khamir C. pseudojiutengensis UICC Y-475, C. saopoulenensis UICC Y-492, Hyp. burtonii UICC Y-496, dan Rh. mucilaginosa UICC Y-513. Seluruh strain yang diuji menunjukkan viabilitas yang tinggi (rerata CFU . 1x 108/ml). Jumlah sel khamir antara lain: C. pseudojiutengensis UICC Y-475 (1,08 x 108 CFU/ml), C. saopoulenensis UICC Y-492 (0,65 x 108 CFU/ml), Hyp. burtonii UICC Y-496 (1,76 x 108 CFU/ml), dan Rh. mucilaginosa UICC Y-513 (2,13 x 108 CFU/ml).

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The study was aimed to isolate and identify phylloplane yeasts from Broussonetia papyrifera plants from Bandung (Dago Pojok), Garut (Tunggilis and Sukadanu), and Trowulan; to investigate the yeasts with antagonistic abilities against moulds which attack post-harvest tomato fruits; and to observe the yeast viability after preservation at a temperature of -80 oC. Two thousand five hundred and forty-three yeast isolates were obtained using the washing method and the membrane filter method. Eighty-two representative yeast isolates were selected based on similarity of colony morphology. Identification was based on sequence data of internal transcribed spacer regions of ribosomal DNA (ITS rDNA). The identification result showed that the 82 representative isolates were consisted of 17 genera and 32 species. Eleven of these genera are belong to Saccharomycetes and one genus belongs Dothidiomycetes (Ascomycota). Six genera are belong to Tremellomycetes, Microbotryomycetes, and Ustilaginomycetes (Basidiomycota). Three representative moulds obtained from the pathogenicity test were able to cause serious damage on post-harvest tomato fruits. These moulds were identified as, i.e. Alternaria alternata, Lasiodiplodia theobromae, and Syncephalastrum racemosum. Six antagonistic yeasts were able to inhibit growth and sporulation of post-harvest tomato moulds, i.e. Candida saopaulonensis UICC Y-492, Candida pseudojiufengensis UICC Y-475, Debaryomyces hansenii UICC Y-488, Geotrichum candidum UICC Y-495, Hyphopichia burtonii UICC Y-496, and Rhodotorula mucilaginosa UICC Y-476. The antagonistic yeasts were tested for their abilities to inhibit growth of A. alternata and L. theobromae which cause fruit rot on post-harvest tomatoes at 26--28oC for 15 days. Candida pseudojiufengensis UICC Y-475 was able to inhibit growth of A. alternata and reduce fruit rot symptoms in tomato fruit (100%). Candida saopoulenensis UICC Y-492 and Rh. mucilaginosa UICC Y-513 were able to inhibit growth of L. theobromae and reduce fruit rot symptoms in tomato fruit (67%). The yeast viability was observed after being preserved at -80oC on day-1 (H1), day-7 (H7), day-14 (H14), day-30 (H-30), and day-180 (H-180). The results showed that all strains do not lose their viability after freezing at -80oC for 180 days. The number of cells for each strain after revival from preservation after 180 days were counted: C. pseudojiufengensis UICC Y-475 (1,08 x 108 CFU/ml), C. saopoulenensis UICC Y-492 (0,65 x 108 CFU/ml), Hyp. burtonii UICC Y-496 (1,76x 108 CFU/ml), and Rh. mucilaginosa UICC Y-513 (2,13 x 108 CFU/ml).

Abstrak :
Pisang Cavendish (Musa acuminata Colla) merupakan salah satu kultivar pisang yang menghadapi ancaman serius berupa serangan penyakit layu Fusarium yang disebabkan oleh infeksi kapang patogen Fusarium oxysporum f. sp. cubense (Foc). Penyakit layu Fusarium menyebabkan penurunan penurunan kaualitas dan produksi tanaman pisang. Penggunaan mikroorganisme sebagai biokontrol dapat dikembangkan untuk alternatif fungisida dalam pengendalian penyakit layu Fusarium di tanaman pisang. Streptomyces spp. diketahui mampu memproduksi senyawa metabolit yang bersifat antifungi dan menekan pertumbuhan patogen. Tujuan dari penelitian ini adalah untuk memperoleh, mengetahui aktivitas biokontrol, dan mengidentifikasi isolat yang diduga sebagai Streptomyces spp. yang diisolasi dari PT Green Giant Pineapple (GGP), Lampung Timur. Metode yang dilakukan dalam penelitian ini adalah pengujian secara in vitro yang meliputi uji aktivitas enzim protease, kitinase, selulase, peroksidase, siderofor, amonia, HCN, dan katalase. Pengujian dilanjutkan dengan identifikasi secara molekuler dan uji kompatibilitas antarisolat. Isolat 1H31, 2H44, 3H32, 3H42, dan 5H5 berhasil diisolasi dari tanah Perkebunan pisang. Isolat terseleksi mampu menghambat kapang Foc dan saling kompatibel. Isolat 3H42 dan 5H5 menunjukkan aktivitas biokontrol yang paling baik yang diketahui dari hasil positif yang ditunjukkan pada semua uji aktivitas biokontrol yang dilakukan. Kelima isolat terseleksi diketahui memiliki kemiripan secara morfologis dan filogenetik dengan S. malaysiensis, S. scabei, S. cameroonensis, S. abikoensis, dan S. katrae. ......Cavendish banana (Musa acuminata Colla) is one of the banana cultivars that faces a serious threat in the form of Fusarium wilt disease caused by infection with the pathogenic fungus Fusarium oxysporum f. sp. cubense (Foc). Fusarium wilt disease causes a decrease in the quality and production of banana plants. The use of microorganisms as biocontrol can be developed as an alternative to fungicides to control Fusarium wilt disease in banana plants. Streptomyces spp. is known to produce metabolite compounds that are antifungal and suppress pathogen growth. The purpose of this study was to obtain, determine the biocontrol activity, and identify isolates suspected as Streptomyces spp. isolated from PT Green Giant Pineapple (GGP), East Lampung. The method used in this research is in vitro testing which includes enzyme activity tests of protease, chitinase, cellulase, peroxidase, siderophore, ammonia, HCN, and catalase. The test was continued with molecular identification and compatibility test between isolates. Isolates 1H31, 2H44, 3H32, 3H42, and 5H5 were successfully isolated from banana plantation soil. The selected isolates were able to inhibit Foc mold and were mutually compatible. Isolates 3H42 and 5H5 showed the best biocontrol activity known from the positive results shown in all biocontrol activity tests conducted. The five selected isolates are known to have morphological and phylogenetic similarities with S. malaysiensis, S. scabei, S. cameroonensis, S. abikoensis, and S. katrae.

Abstrak :
lants provide insects with a range of specific foods, such as nectar, pollen, and food bodies. In exchange, they may obtain various services from arthropods. The role of food rewards in the plant-pollinator mutualism has been covered broadly. This book addresses another category of food-mediated interactions, focusing on how plants use foods to recruit arthropod "bodyguards" as a protection against herbivores." "Many arthropods with primarily carnivorous lifestyles require plant-provided food as an indispensable part of their diet. Only recently have we started to appreciate the implications of non-prey food for plant-herbivore-carnivore interactions. Insight into this aspect of multitrophic interactions is not only crucial to our understanding of the evolution and functioning of plant-insect interactions in natural ecosystems, it also has direct implications for the use of food plants and food supplements in biological control programs.". "This edited volume provides essential reading for all researchers interested in plant-insect interactions."--BOOK JACKET.