First report of Coleus blumei viroid 1 in commercial Coleus blumei in the United States

Coleus scutellarioides (syn. Coleus blumei) is a widely grown evergreen ornamental plant valued for its highly decorative variegated leaves. Six viroids, named Coleus blumei viroid 1 to 6 (CbVd-1 to -6) have been identified in coleus plants in many countries of the world (Nie and Singh 2017), including Canada (Smith et al. 2018). However there have been no reports of Coleus blumei viroids occurring in the U.S.A. (Nie and Singh 2017). In April 2021, leaf tissue samples from 27 cultivars of C. blumei, one plant of each, were submitted to the University of Idaho laboratory from a commercial nursery located in Oregon to screen for the presence of viroids. The sampled plants were selected randomly and no symptoms were apparent in any of the samples. Total nucleic acids were extracted from each sample (Dellaporta et al. 1983) and used in reverse-transcription (RT)-PCR tests (Jiang et al. 2011) for the CbVd-1 and CbVd-5 with the universal primer pair CbVds-P1/P2, which amplifies the complete genome of all members in the genus Coleviroid (Jiang et al. 2011), and two additional primer pairs, CbVd1-F1/R1 and CbVd5-F1/R1, specific for CbVd-1 and CbVd-5, respectively (Smith et al. 2018). Five C. blumei plants (cvs Fire Mountain, Lovebird, Smokey Rose, Marrakesh, and Nutmeg) were positive for a coleviroid based on the observation of the single 250-nt band in the RT-PCR test with CbVds-P1/P2 primers. Two of these CbVd-1 positive plants (cvs Lovebird and Nutmeg) were also positive for CbVd-1 based on the presence of a single 150-nt band in the RT-PCR assay with CbVd1-F1/R1 primers. One plant (cv Jigsaw) was positive for CbVd-1, i.e. showing the 150-nt band in RT-PCR with CbVd1-F1/R1 primers, but did not show the ca. 250-bp band in RT-PCR with primers CbVds-P1/P2. None of the tested plants were positive for CbVd-5, either with the specific, or universal primers. All coleviroid- and CbVd-1-specific PCR products were sequenced directly using the Sanger methodology, and revealed whole genomes for five isolates of CbVd-1 from Oregon, U.S.A. The genomes of the five CbVd-1 isolates displayed 96.9-100% identity among each other and 96.0-100% identity to the CbVd-1 sequences available in GenBank. Because the sequences from cvs Lovebird, Marrakesh, and Nutmeg, were found 100% identical, one sequence was deposited in GenBank (MZ326145). Two other sequences, from cvs Fire Mountain and Smokey Rose, were deposited in the GenBank under accession numbers MZ326144 and MZ326146, respectively. To the best of our knowledge, this is the first report of CbVd-1 in the United States.

Aktivitas Anticestoda In Vitro Metabolit Sekunder Daun Miana (Coleus blumei. Benth) terhadap Cacing Hymenolepis microstoma

Penelitian ini untuk mengetahui golongan senyawa metabolit sekunder dari ekstrak daun miana (Coleus blumei. Benth) yang memiliki aktivitas anticestoda. Daun miana kering diekstraksi dengan metode yang sesuai untuk mendapatkan golongan senyawa metabolit sekunder alkaloid, flavonoid, tanin, dan steroid. Aktivitas anticestoda diukur dengan menghitung waktu kematian cacing Hymenolepis microstoma pada setiap golongan metabolit sekunder konsentrasi 10%. Hasil penelitian menunjukkan tanin memiliki aktivitas anticestoda yang kuat yang tidak berbeda dengan praziquatel sebagai anthelmintik komersial. Akivitas anticestoda flavonoid mirip dengan tanin akan tetapi aktivitasnya masih dibawah praziquatel. Alkaloid dan steroid memiliki aktivitas anticestoda yang lebih rendah dibandingkan dengan tanin dan flavonoid. Hasil penelitian ini membuktikan bahwa tanin sebagai senyawa metabolit sekunder yang paling aktif sebagai anticestoda dibandingkan flavonoid, alkaloid, dan steroid.

Toksisitas Akut Ekstrak Daun Miana (Coleus Blumei Benth) pada Mencit (Mus Musculus)

Coleus blumei memiliki berbagai khasiat untuk mengobati berbagai macam penyakit termasuk kecacingan. Sampai saat ini belum diketahui tingkat dosis yang menyebabkan toksisitas bagi pemakainya. Tujuan penelitian ini adalah untuk mengevaluasi toksisitas akut ekstrak etanol daun miana pada mencit. Pengujian toksisitas dilakukan pada mencit dengan pemberian per oral untuk menentukan toksisitas akut dan dosis letal 50% (LD50). Hasil penelitian menunjukkan ekstrak daun miana memiliki toksisitas yang rendah. Hasil analisis probit menunjukkan LD50 ekstrak etanol daun miana adalah 9757.14 mg/kg berat badan. Gejala klinis yang terlihat pada mencit sebelum mati adalah tidak aktif, lemah, ritme pernapasan menurun dan bulu berdiri. Pemeriksaan patologi anatomi menunjukkan perdarahan pada rongga perut ditemukan pada dosis 10000 mg/kg bb ekstrak etanol. Hasil pemeriksaan histopatologi menunjukkan adanya pembendungan, oedema, dilatasi tubuli pada organ ginjal. Degenerasi dan nekrosis ditemukan pada organ usus, hati dan ginjal yang meningkat seiring dengan peningkatan dosis ekstrak. Berdasarkan nilai LD50 ekstrak etanol daun miana termasuk dalam kategori toksik ringan. Walaupun termasuk dalam katagori toksik ringan, akan tetapi mulai pada dosis 4000 mg/kg bb ekstrak daun miana menyebabkan degenerasi dan nekrosa sel pada organ usus, hati, dan ginjal.

Toxicity of Miana Leaf (Coleus blumei) Extract Against Houseflies (Musca domestica)

Houseflies (Musca domestica) is an disease-carrying insect that plays an important role in the spread of disease in humans and animals. One way to control houseflies is using Miana leaves (Coleus blumei) as botanical pesticide. The purpose of this study was to determine the chemical compounds contained in Miana leaf as well as determine the optimal concentration of Miana leaf extract in causing knockdown effect in houseflies. Miana leaf fine powder was soaked with methanol (maceration) for 3 days followed byphytochemical screening (chemical reagents and Gas Chromatography Mass Spectrophotometry (GCMS) and anti-houseflies toxicity tests. Testing of methanolic extract of Miana leaves was made in the form of spray using the knockdown method at concentrations of 5%, 10%, 20%, 30% and 40% and observed in 5, 10 and 15 minutes. The results of phytochemical screening with chemical reagents showed that the extract contained alkaloids, tannins, flavonoids, saponins and terpenoids; while the results of GCMS analysis showed 8 bioactive compounds. The results of the study revealed that at a concentration of 30% and 40%, methanolic extract of Miana leaves could result in a knockdown effect that was accompanied by death with a percentage value of 100% in the first 5 minutes of observation. This research shows that methanolic extract of Miana leaves can be used as an alternative to botanical pesticides in controlling houseflies (Musca domestica).