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This study was designed to assess the suppressive effects of various anaerobically digested slurries (ADSs), and the microorganisms inhabiting them, against Fusarium wilt in spinach. We used five different ADSs from a range of source materials (dairy cow manure, sewage sludge, food garbage, pig manure, night soil sludge), combined in different proportions. All five raw ADSs suppressed the growth of Fusarium oxysporum f. sp. spinaciae (Fos) on agar plates using a co-culture test. In contrast, filtrate ADSs did not suppress the growth of Fos. In total, 32 bacterial strains were isolated from five ADSs, and 8 isolates showed antagonistic activities against Fos. Based on 16S rDNA sequences, the strain AD-3 isolated from ADS from dairy cow manure belonged to Bacillus velezensis. Genome analysis revealed that AD-3 had two kinds of genes related to the production of the non-ribosomal lipopeptides, fengycin/plipastatin (pps genes), and surfactin (srf genes). In pot assays, inoculation of AD-3 (1.0 × 106 CFU·g−1 dry soil) into Fos-infected soil (1.0 × 105 bud-cells·g−1 dry soil) significantly reduced the severity of Fusarium wilt disease at 28 d after seedling. The percentage reductions in disease severity in two replicates were 64.3% and 44.3%, respectively. Thus, bacterial strain AD-3 could be applied to reduce Fusarium wilt in spinach.

Cucurbits are grown throughout the Java Island as dry season crops. Plants having mosaic, mottling, chlorosis and leaf distortion symptoms were frequently found in most of the cucurbit fields during the survey which conducted in Central Java including Sleman, Kulon Progo, and Klaten during July–September 2000 and 2001. Using double antibody sandwich enzyme-linked immunosorbent assay (DAS-ELISA); Cucumber mosaic virus (CMV), Cucumber green mottle mosaic virus (CGMMV) and Kyuri green mottle mosaic virus (KGMMV) were found infecting cucurbits. CMV was widespread, infecting 48.9% of the samples tested followed by CGMMV (12.8%) and KGMMV (6.4%), while others samples (31.9%) were not tested, double infections were common with 8.5 % of the samples being infected with two viruses (CGMMV and KGMMV) and 34% with three viruses (CMV, CGMMV, and KGMMV). Severe mosaic and mottle symptoms were associated most often with single infection of CGMMV and KGMMV respectively. In addition, these are the first detections of CGMMV and KGMMV infecting cucurbit plants in Indonesia. Tanaman labu-labuan umumnya tumbuh sepanjang musim kemarau diPulau Jawa. Tanaman labu-labuan dengan gejala mosaik, klorosis, mottling dan bentuk daun serta buah yang berubah banyak dijumpai selama survei yang dilakukan di Kulon Progo, Sleman dan Klaten pada bulan Juli sampai September tahun 2000 dan 2001. Deteksi menggunakan metode double antibody sandwich enzyme-linked immunosorbent assay (DAS-ELISA) telah berhasil mengetahui keberadaan dan infeksiCucumber mosaic virus(CMV),Cucumber green mottle mosaic virus (CGMMV) dan Kyuri green mottle mosaic virus (KGMMV) pada tanaman labu-labuan di tiga kabupaten tersebut. CMV menginfeksi tanaman labu-labuan tinggi yaitu 48,9% dari jumlah sampel tanaman yang dikoleksi, kemudian CGMMV (12,8%) dan KGMMV(6,4%), sedangkan sebanyak 14 sampel tanaman (31,9%)tidak dideteksi.Infeksi ganda banyak ditemukan dan 8,5 % sampel tanaman terinfeksi oleh dua jenis virus (CGMMV dan KGMMV) sedangkan 34% sampel tanaman terinfeksi oleh tiga jenis virus (CMV, CGMMV, dan KGMMV). Gejala mosaik dan mottling sering terjadi pada tanaman labu-labuan yang terinfeksi ganda oleh CGMMV dan KGMMV. Hasil penelitian merupakan deteksi pertama CGMMV dan KGGMV pada tanaman labu-labuan di Indonesia.

Cucumber green mottle mosaic virus (CGMMV) and Kyuri green mottle mosaic virus (KGMMV) are seed borne viruses and they are also transmitted mechanically during agricultural practice and through water. Hence, these viruses have potential diseases widely distributed throughout the world. To detect different strains of CGMMV and KGMMV, several specific primers for each virus were designed for single and multiplex RT-PCR. The results of single and multiplex RT-PCR showed that CGMMV was detected in zucchini isolated in Bali-Indonesia, while KGMMV was detected both in zucchini isolated in Bali-Indonesia and Cucumis metuliferus isolated in Thailand. Furthermore, artificial co-infection of these two viruses was prepared and carried out using two different ways of viral RNAs extraction. Based on the results, it could be reported that viral RNAs for cDNA amplification by multiplex RT-PCR could be extracted from a mixture of infected leaves or separate extraction of each viruses infected leaves. In addition, results presented in this study demonstrated the application of multiplex RT-PCR to simultaneously detect CGMMV and KGMMV from cucurbit leaves using a mixture of four primers and its feasibility as a sensitive and rapid laboratory assay. Since, no multiplex RT-PCR technique has been described for the detection of CGMMV and KGMMV, this technique can be a good option for sensitive and reliable tool for detection of two major cucurbit infecting Tobamoviruses.Keywords : Cucurbit infecting Tobamovirus, multiplex RT-PCR, seed borne viruses

Papaya ringspot virus (PRSV) is one of potyviruses causing severe damage to the production of cucurbit crops including melon, however resistant melons to PRSV have not yet commercially available. To find resistant genetic source of melons against PRSV, sixty three melons were manually inoculated with PRSV-papaya strain (PRSV-P) isolated in Thailand. Levels of resistance to PRSV-P accumulation in melon leaf tissue were evaluated using a combination of visual symptom observation and RT-PCR analysis. Among melons tested, Yamatouri, Mawatauri, PI 414723, and PI 371795 showed to be resistance to PRSV-P To study the inheritance of resistance to PRSV-P, breeding experiments were conducted by crossing the resistant Yamatouri with susceptible Vakharman. The genetic analysis results revealed that a single dominant gene conferred resistance to PRSV-P in Yamatouri and its generation.