Sublethal exposure to an emulsion based on Pogostemon cablin (Lamiaceae) essential oil impairs digestibility, feeding, fecundity, and mobility of the coffee berry borer, Hypothenemus hampei

The global search for eco-friendly and human-safe pesticides has intensified, and research on essential oils (EOs) has expanded due to their remarkable insecticidal activities and apparent human-safe. Despite this, most of the literature focuses on short-term and simplified efforts to understand lethal effects, with only a few comprehensive studies addressing sublethal exposures. To fill this shortcoming, we explore the lethal and sublethal effects of Pogostemon cablin (Lamiaceae) EO and an EO-based emulsion (18%) using the coffee berry borer Hypothenemus hampei Ferrari (Coleoptera: Curculionidae: Scolytinae) as a model. First, we determine the toxicity of EO and EO-based emulsion using dose-mortality curves and lethal times. Second, we subjected adult females of H. hampei to sublethal doses to assess whether they affected their behavior, reproductive output, and histological features. Our findings reveal that patchoulol (43.05%), α-Guaiene (16.06%), and α-Bulnesene (13.69%) were the main components of the EO. Furthermore, the EO and its emulsion had similar toxicity, with dose-mortality curves and lethal times overlapping 95% confidence intervals. We also observed that sublethal exposure of females of H. hampei reduces reproduction and feeding, increases walking activity, and causes histopathological changes in the midgut. This study advances the knowledge of sublethal effects of an eco-friendly substance on insects.

Light intensities alter growth and essential oil of patchouli under shade nets

ABSTRACT: Pogostemon cablin (Blanco) Benth. is an aromatic species popularly known as patchouli. The essential oil rich in patchoulol extracted from leaves is used by the pharmaceutical industries. The objective was to investigate the effects of shade nets and shading intensities on P. cablin growth, anatomy, chemical composition and essential oil content. The experiment was conducted with two types of shade nets (black and Aluminet), three light intensities (30, 50, and 70% shading) and full sun. The different light intensities influenced the growth and the essential oil yield, and chemical composition. Patchouli plants grown in an environment with shading showed higher values for the leaf, stem, root ant total dry weights compared to full sun. At 50% of shading, Aluminet provided gain in stem and total dry weights. Aluminet and black net at 50 and 70% of shading enhance essential oil yield. Patchoulol and pogostol contents were higher under full sun, and, black net and Aluminet at 50% shading. The environment for patchouli cultivation can be improved by use shade nets, especially with Aluminet at 50% of shading.

Antagonistic screening of Trichoderma spp. isolated from patchouli rhizosphere

The objective of this research was to determine the antagonistic activity of Trichoderma spp. isolated from patchouli rhizosphere (Pogostemon cablin Benth.). Another objective was to perform antagonistic screening of these fungi to inhibit the growth of the wilted pathogen Fusarium spp. In vitro research was conducted in the Laboratory of Plant Pathology, Universitas Syiah Kuala, from January to June 2020. The study used a completely randomised design with five treatments and three replications. The antagonistic screening was carried out by using the dual culture method of Trichoderma spp. against Fusarium spp. with the medium of Potato Dextrose Agar (PDA). The result showed that five isolates of Trichoderma have different antagonistic percentages in inhibiting the Fusarium. The highest antagonistic activity was found from isolate 2 and the lowest value was shown by isolate 3.

Analisis Kadar Patchouli Alcohol Menggunakan Gas Chromatography– Mass Spectrometry (GC – MS) pada Pemurnian Minyak Nilam (Pogostemon cablin B.) Aceh Tamiang dengan Nanomontmorillonite

Tanaman nilam (Pogostemon cablin Benth.) merupakan salah satu tanaman penghasil minyak atsiri atau yang lebih dikenal dengan nama Patchouli Alcohol (PA). PA merupakan senyawa yang terbesar di dalam minyak nilam sebagai penentu mutu minyak nilam, kadar PA dalam minyak nilam menurut SNI 06-2385-2006 yaitu minimal 30%. Sampel minyak nilam yang digunakan adalah minyak nilam yang berasal dari Aceh Tamiang. Tujuan penelitian ini dilakukan untuk mengetahui kadar PA sebelum dan sesudah adsorbsi menggunakan Nanomontmorillonite (Nano-MMT) sebagai adsorben dengan menggunakan metode kualitatif dengan uji warna dan metode kuantitatif dengan analisis Gas Cromatography Mass Spectrometry (GC-MS) untuk menentukan kadar PA, mengingat Nano-MMT adalah jenis tanah liat (clay) yang dapat digunakan sebagai adsorben yang mengadsorpsi kontaminan metalik dengan baik dikarenakan Nano-MMT mempunyai muatan negatif yang dapat mengikat spesies yang bermuatan positif kontaminan metalik seperti logam berat. Berdasarkan hasil analisis diketahui bahwa kadar PA sebelum diadsorpsi 7,74% b/v, dan kadar PA setelah diadsorpsi berkisar antara 4,47%-7,86% b/v, kadar tersebut belum sesuai dengan SNI. Hal ini disebabkan karena banyak hal diantaranya terdapat komponen pengotor berupa kontaminan metalik seperti logam, terjadinya oksidasi, tercampurnya minyak nilam dengan bahan lain, pencemaran wadah penyulingan minyak, dan waktu penyimpanan yang relatif lama.

Coexpression Analysis Identified PcMYB25 as a Patchoulol Synthase Gene Activator to Enhance Patchouli Alcohol Biosynthesis in Pogostemon Cablin

BackgroundPatchouli alcohol is an effective component of the medicinal plant patchouli. Similar to other secondary metabolites, its synthesis is likely also regulated by transcription factors. Although the biosynthetic pathway of patchouli alcohol has been characterized, the regulatory mechanism of patchouli alcohol biosynthesis has not been fully revealed.ResultsThis study combined the transcriptome data of patchouli leaves treated with different hormones and WGCNA to establish a coexpression network. The modules correlated to patchouli alcohol content were identified, and PcMYB25 played a crucial role in regulating patchouli alcohol biosynthesis. The overexpression of PcMYB25 can promote the expression of patchouli alcohol synthase (PTS), thereby increasing the content of patchouli alcohol.Conclusions This is the first report that MYB25 regulates the secondary metabolism of patchouli. These experimental results lay the foundation for further analysis of the regulatory mechanism of patchouli alcohol synthesis.

Bioactivities of Lamiaceae, Myristicaceae, and Myrtaceae plant oils against Nilaparvata lugens Stâl. (Hemiptera: Delphacidae)

Essential oil (EO) plants have properties as botanical insecticides. Some of them come from the families of Lamiaceae, Myristicaceae, and Myrtaceae. A plant belonging to the Lamiaceae includes patchouli (Pogostemon cablin), while the Myristicaceae includes nutmeg (Myristica fragrans), and the Myrtaceae includes clove (Syzygium aromaticum) and cajuput (Melaleuca cajuput subsp. cajuputi). This research aimed to evaluate toxicity, feeding inhibition, and oviposition deterrent from four EO plants from the Lamiaceae, Myristicaceae, and Myrtaceae to brown rice planthopper Nilaparvata lugens (Hemiptera: Delphacidae), the main pest of rice. The results showed that cajuput and patchouli oil gave more potent toxicity to N. lugens with LC50 and LC95 were 0.016% and 4.87% for cajuput oil and 0.019% and 5.25% for patchouli oil. Cajuput oil at 0.002% deterred oviposition 51.74% and inhibited feeding on 0.016% as many as 71.52% with strong enough criteria to the fourth instar nymphs of N. lugens. Patchouli oil deterred oviposition from 0.002% as much as 61.15% and inhibited feeding on 0.019% as many as 68.73% with strong enough criteria. The highest oviposition deterrent was 83.2% on patchouli oil at the concentration of 0.188%, whereas the highest feeding inhibition was 82.78% on cajuput oil at the concentration of 0.169%.

PENGARUH JARAK TANAM DAN KONSENTRASI PUPUK CAIR SUPRATAN TERHADAP PERTUMBUHAN TANAMAN NILAM (Pogostemon cablin Benth)

Tanaman nilam (Pogostemon cablin Benth) merupakan tanaman perkebunan penghasil minyak atsiri, dan memiliki fungsi utama sebagai bahan baku pengikat (fiksasif). Salah satu faktor yang mempengaruhi pertumbuhan tanaman nilam adalah kurangnya unsur hara dan jarak tanam saat penanaman. Penelitian ini bertujuan untuk mengetahui pengaruh jarak tanam dan pupuk cair supratan terhadap pertumbuhan tanaman nilam. Penelitian ini dilaksanakan pada bulan Mei sampai dengan September 2021 di Desa Kabua-Bua, Kecamatan Nuhon, Kabupaten Banggai. Penelitian ini menggunakan Rancangan Acak Kelompok (RAK) pola faktorial. Faktor pertama konsentrasi pupuk cair supratan (A) yang terdiri dari 3 taraf dan faktor kedua adalah jarak tanam (B) yang juga terdiri dari 3 taraf. Setiap kombinasi perlakuan diulang 3 kali sehingga seluruhnya terdapat 27 percobaan. Hasil penelitian menunjukkan bahwa perlakuan interaksi jarak tanam 5 mL pupuk Cair Supratan /Liter air + Jarak tanam 40cm x 50cm (A3B1) merupakan perlakuan terbaik terhadap parameter jumlah tunas pada umur tanaman 6, 8 dan 10 MST dan perlakuan 5 mL pupuk Cair Supratan /Liter air (A3) merupakan perlakuan terbaik terhadap variabel jumlah tunas pada umur tanaman 12, 14, 16, 18, dan 20 MST. Pada pengamatan variabel jumlah daun, perlakuan interaksi jarak tanam 5 mL pupuk Cair Supratan /Liter air + Jarak tanam 40cm x 60cm (A3B2) merupakan perlakuan terbaik pada umur tanaman 8 MST, dan perlakuan jarak tanam 40cm x 70cm (B3) merupakan perlakuan terbaik pada umur tanaman 10 dan 12 MST. Selain itu, perlakuan 5 mL pupuk Cair Supratan /Liter air (A3) merupakan perlakuan terbaik pada umur tanaman 16, 18 dan 20 MST