Fruit flies (Diptera: Tephritidae) are major pests of chili (Capsicum annuum Linnaeus) in tropical agroecosystems, but information on species dominance, infestation levels, and field susceptibility patterns of local chili varieties in West Sumatra remains limited. This study investigated Bactrocera spp. diversity, infestation levels, and varietal susceptibility patterns across four major chili-producing regencies in West Sumatra, Indonesia. Field surveys were conducted from July 2024 to March 2025 at 33 chili-growing sites in Agam, Solok, Tanah Datar, and Padang Pariaman. Fruit flies were monitored using methyl eugenol-baited modified Lynfield traps, while plant and fruit infestation were assessed through field observation and fruit dissection. Species diversity was evaluated using Shannon–Wiener, Simpson, and Pielou evenness indices. Differences in infestation among varieties were analyzed using the Kruskal–Wallis followed by Dunn’s multiple comparison test, while exploratory PCA and clustering were used to visualize infestation patterns. This study identified three fruit fly species associated with chili agroecosystems in West Sumatra, namely Bactrocera dorsalis, B. carambolae, and B. umbrosa. Among them, Bactrocera dorsalis overwhelmingly dominated the assemblages, resulting in low species diversity and evenness across regencies. Infestation levels differed among varieties, with Kuhay consistently showing the lowest plant, fruit, and overall infestation intensity. Aka, Keriting Bukittinggi, Rawit, and Kopay showed relatively higher infestation levels, although Kopay should be interpreted cautiously due to limited sample representation. These findings indicate differential field susceptibility among local chili varieties and suggest that low-infestation varieties such as Kuhay warrant further evaluation for integrated pest management and resistance-oriented breeding programs.
Tobacco cutworm, Spodoptera litura Fabricius is a polyphagous pest that attacks green mustard and may cause substantial yield losses. Entomopathogenic fungi, including Metarhizium anisopliae Metsch., offer an environmentally friendly alternative to synthetic insecticides. This study aimed to evaluate the bioinsecticidal activity of a local isolate of M. anisopliae against third-instar S. litura larvae on green mustard under laboratory conditions. The experiment was arranged in a completely randomized design with six suspension treatments (0, 10, 20, 30, 40, and 50 g/L in distilled water) and five replications, with 10 larvae in each experimental unit. The observed variables included isolate identification, total mortality, initial time of death, LT₅₀, LC₅₀, LC₉₅, daily mortality, and behavioral and morphological changes in infected larvae. This study confirmed that the local isolate of M. anisopliae is pathogenic to S. litura larvae on green mustard, causing high larval mortality, and a shorter lethal time at higher concentrations. Although the highest mortality was recorded at 50 g/L, the 30 g/L treatment showed comparable effectiveness to higher concentrations, indicating its potential as an efficient concentration for larval control.
Fusarium oxysporum f. sp. cubense (Foc) adalah patogen penyebab penyakit layu fusarium pada tanaman pisang yang tersebar merata di seluruh Indonesia. Salah satu upaya pengendalian penyakit yang banyak dilakukan adalah penggunaan biopestisida yang memanfaatkan jamur antagonis. Tujuan penelitian ini adalah untuk mengetahui efektivitas jamur indigenous (berasal dari akar pisang) dalam mengendalikan penyakit layu fusarium pada pisang Barangan merah. Penelitian dilaksanakan di Laboratorium dan uji lapangan Pusat Riset Hortikultura BRIN di Solok. Isolat jamur indigenous dan Foc yang digunakan merupakan koleksi isolat BRIN. Rancangan penelitian menggunakan rancangan kelompok acak dengan 6 perlakuan dan 4 ulangan, masing-masing perlakuan terdiri atas 5 tanaman. Tanaman pisang Barangan merah berumur dua bulan, hasil kultur jaringan, diinokulasi dengan cara menanamkan propagul jamur ke dalam tanah: A = tanpa penambahan jamur indigenous, (kontrol), B = Fusarium sp. 1, C = Fusarium sp. 2, D = Fusarium sp. 3, E = Trichoderma sp., F = jamur tak teridentifikasi dari tanah sekitar akar. Hasil penelitian menunjukkan bahwa penambahan Fusarium sp. 2 mampu memperpanjang masa inkubasi penyakit pada tanaman pisang hingga 47,33 hari, sedangkan masa inkubasi penyakit pada tanaman tanpa penambahan jamur indigenous hanya 30,44 hari. Fusarium sp. 2 juga menurunkan intensitas penyakit menjadi 66,35%, sementara pada tanaman tanpa jamur indigenous intensitas penyakit mencapai 79,05%. Penambahan jamur indigenous tidak berpengaruh terhadap peningkatan tinggi tanaman, lingkar batang, maupun jumlah daun pada tanaman berumur 3 bulan setelah inokulasi jamur indigenous.
Viral diseases severely affect papaya (Carica papaya Linnaeus) production in Indonesia, but information on papaya ringspot virus (PRSV) isolates from severe outbreaks in Sleman Regency remains limited. This study aimed to identify the causal virus and evaluate its mechanical transmissibility to selected cucurbit hosts. A composite leaf sample from five symptomatic papaya plants was tested for potyvirus and begomovirus using universal primers. The potyvirus amplicon was sequenced and analyzed using BLASTn, phylogenetic analysis, and pairwise nucleotide identity analysis based on a 462 bp trimmed partial coat protein region. Mechanical transmission was tested on cucumber (Cucumis sativus), melon (Cucumis melo), and bitter gourd (Momordica charantia), followed by symptom observation and RT-PCR confirmation. This study identified identified the virus as PRSV-P, registered as PRSV-SMN-TJ, accession number PX927038. Disease incidence after inoculation ranged from 50% to 100%. Phylogenetic and nucleotide identity analyses placed the PRSV-SMN-TJ isolate within the same cluster as Indonesian and Thailand PRSV isolates. This study was based on a single composite field sample and a limited host transmission assay; therefore, broader sampling, complete diagnostic controls, and quantitative pathogenicity assessment are needed. Nevertheless, these findings provide baseline information for PRSV surveillance and management planning in papaya-growing areas.
Endophytic fungi hold considerable potential as biological control agents, yet their exploration from pineapple plants cultivated on peatlands remains limited. This study aimed to identify the diversity of endophytic fungi associated with pineapple (Ananas comosus) grown in Kualu Nenas, Riau, and to evaluate their entomopathogenic activity against the pineapple mealybug, Dysmicoccus brevipes. Endophytic fungi were isolated from leaf sheaths and roots of 1-year-old and 15-year-old pineapple plants. A total of 24 fungal isolates were obtained and morphologically identified into five genera: Beauveria sp., Metarhizium sp., Trichoderma sp., Fusarium sp., and Aspergillus sp. Preliminary pathogenicity screening against Tenebrio molitor larvae showed that 7 of the 24 isolates exhibited entomopathogenic activity, causing 33.33–100% mortality. Five isolates that caused >50% mortality were further evaluated against second-instar D. brevipes nymphs using a conidial suspension of 1 × 10⁸ conidia/ml. Among these isolates, Beauveria sp. KN1-D27 showed the highest virulence, causing 82% mortality at 10 days after treatment, with the shortest LT₅₀ of 6.4 days. This was followed by Metarhizium sp. KN1-A09, which caused 71% mortality with an LT₅₀ of 7.2 days, and Beauveria sp. KN15-D15, which caused 66% mortality with an LT₅₀ of 7.8 days. In contrast, Trichoderma sp. and Fusarium sp. showed lower efficacy. These findings indicate that Beauveria sp. KN1-D27 has potential as a biological control candidate against D. brevipes on peatland pineapple.
Spodoptera frugiperda is a major invasive pest of maize that requires effective control strategies. Entomopathogenic fungi are promising biological control agents because they can infect larvae and disrupt insect development. However, information on indigenous fungal isolates from West Sumatra, Indonesia remains limited. Moreover, their effects on post-larval development of S. frugiperda are still poorly understood. This study aimed to evaluate the pathogenicity of several fungal isolates against S. frugiperda under laboratory conditions. The experiment was arranged in a Completely Randomized Design (CRD) with eight treatments and four replications. The treatments consisted of six fungal isolates (Beauveria bassiana BBWS, B. bassiana BBPD, Metarhizium anisopliae B22C, M. anisopliae KRJ, Trichoderma asperellum A116, T. asperellum S2D11) and two controls (sterile distilled water and cypermethrin). Fungal suspensions were applied to second-instar larvae at 1 × 10⁸ conidia mL⁻¹. All data were analyzed using ANOVA followed by the LSD test at the 5% level. This study showed that the entomopathogenic fungal isolates tested affected the survival and postlarval development of S. frugiperda under laboratory conditions. The fungal treatments caused larval mortality ranging from 40 - 70% and reduced the proportion of larvae into the pupal and adult stages. Among the tested isolates, B. bassiana BBWS was the most effective, causing the highest larval mortality, the shortest LT₅₀, and the lowest pupal and adult formation. However, further research is needed to confirm the pathogenicity mechanisms of the isolates, their conidial viability and stability during storage, and their efficacy under greenhouse and field conditions.
Cherelle wilt merupakan gangguan fisiologis yang menyebabkan kehilangan hasil yang tinggi pada tanaman kakao pada fase awal perkembangan buah. Tujuan dari penelitian ini yaitu mengevaluasi efektivitas aplikasi boron secara foliar dalam menekan kejadian cherelle wilt dan meningkatkan keberhasilan fase generatif kakao. Penelitian dilaksanakan pada bulan April-Agustus 2025 di kelompok tani Sidodadi, Putat, Patuk, Gunungkidul, Yogyakarta. Penelitian menggunakan rancangan acak kelompok lengkap dengan dua faktor, yaitu faktor pertama klon kakao (MCC01 dan MCC02) dan faktor kedua adalah konsentrasi boron 0, 2, 4, dan 8 (g/l). Parameter yang diamati meliputi jumlah bunga, jumlah cherelle wilt, jumlah layu pentil akibat serangan hama Helopeltis sp, dan jumlah pentil sehat. Hasil penelitian menunjukkan bahwa aplikasi boron secara foliar mampu menurunkan persentase cherelle wilt secara nyata. Setiap klon menunjukkan konsentrasi boron optimum untuk menekan layu pentil, kombinasi klon MCC01 memberikan respons terbaik pada konsentrasi 4 g/l, sedangkan klon MCC02 pada konsentrasi 2 g/l. Kombinasi klon MCC02 dan konsentrasi boron 4 g/l menghasilkan jumlah bunga tertinggi, sementara kejadian layu pentil kakao fisiologis terendah diperoleh pada kombinasi klon MCC02 dan konsentrasi boron 2 g/l. Pengelolaan boron yang tepat melalui aplikasi foliar efektif dalam mengurangi penyakit fisiologis cherelle wilt dan meningkatkan produktivitas kakao.
Fusarium wilt disease caused by Fusarium oxysporum f. sp. cubense (Foc) is a major constraint in banana cultivation, and its development in the field is frequently associated with improper nitrogen fertilization. However, information on how different nitrogen fertilizer rates influence Fusarium wilt severity remains limited. This study aimed to evaluate the effect of varying nitrogen doses on Fusarium wilt and growth of banana. The experiment was conducted under laboratory and field conditions at the Horticulture Research Center of BRIN, Solok, Indonesia, using a randomized block design with nine treatments and four replications. The treatments were nitrogen with different rates (control, 100, 250, 400, and 550 kg ha⁻¹ year⁻¹), applied with and without Foc inoculation. The results demonstrated that nitrogen fertilization enhanced vegetative growth of banana plants under pathogen-free conditions. However, in Foc-infected plants, increasing nitrogen rates—particularly at high levels—exacerbated disease development. High nitrogen rates (400–550 kg ha⁻¹ year⁻¹) accelerated symptom appearance, indicated by shorter incubation periods, and increased disease severity. In contrast, a moderate nitrogen rate (250 kg ha⁻¹ year⁻¹) delayed symptom development and reduced disease severity, although it did not prevent infection. These findings suggest that excessive nitrogen fertilization increases Fusarium wilt severity, while moderate nitrogen application may help suppress disease progression. Therefore, nitrogen management in Fusarium wilt–endemic banana production areas should prioritize moderate nitrogen rates and avoid excessive fertilization as part of an integrated and sustainable disease management strategy.
Mealybugs (Hemiptera: Pseudococcidae) are important pests that threaten cassava in Bali; however, detailed information on their community structure and spatial distribution remains limited. This study aimed to analyze the community structure and spatial distribution patterns of mealybugs infesting cassava across Bali Province, Indonesia. Field sampling was conducted in nine regencies—Jembrana, Tabanan, Buleleng, Badung, Denpasar, Gianyar, Bangli, Klungkung, and Karangasem—using a diagonal sampling method. In each regency, five sampling units were established, with five cassava plants observed per unit. On each plant, three upper, middle, and lower leaves were examined. The results of the study showed four mealybug species: Phenacoccus manihoti, Paracoccus marginatus, Ferrisia virgata, and Pseudococcus jackbeardsleyi, with species richness index values ranging from 0.368 to 0.388. All species were recorded in all surveyed regencies and exhibited a predominantly random spatial distribution pattern, as indicated by a variance-to-mean ratio (S²/X ≈ 1). Overall dominance was highest for P. marginatus (46.23%), particularly in Karangasem, followed by P. manihoti (45.72%) in Denpasar. The mealybug community structure was characterized by a diversity index (H′) ranging from 0.73 to 1.22, an evenness index (E) ranging from 0.16 to 0.24, and a dominance index (C) ranging from 0.32 to 0.54, indicating spatially variable communities that ranged from relatively stable to less stable conditions. These findings provide the baseline data on the community structure and spatial distribution of mealybugs on cassava in Bali, offering important insights for developing targeted monitoring and sustainable pest management strategies.
Para-menthane-3,8-diol (PMD), derived from citronellal of citronella plants, has potential as an eco-friendly botanical insecticide for controlling Spodoptera frugiperda. This study aimed to evaluate the physiological interference caused by a PMD nanoemulsion formulation on S. frugiperda. Bioassays were conducted using the leaf-dip method. Data were analyzed using analysis of variance (ANOVA), followed by the Least Significant Difference (LSD) test with Statistix 8 and Duncan’s multiple range test at a 5% significance level using SPSS version 25. Probit analysis with POLO PLUS was performed to determine LC₂₅ and LC₅₀ values. The results showed that PMD nanoemulsion induced significant physiological interference in S. frugiperda, as indicated by increased mortality with LC₂₅ and LC₅₀ values of 0.15% and 0.48%, respectively. At a concentration of 0.75%, the treatment disrupted development by reducing pupation and adult emergence to 30% and altering the sex ratio to 1 male: 0.22 female. Sublethal interference was evident through strong antifeedant activity (62.88%) and pronounced changes in physiological parameters, including consumption rate (0.0328 mg/day), growth rate (0.0023 mg/day), and efficiency of ingested food (6.0029 mg/day). Overall, the PMD nanoemulsion formulation interfered with survival, feeding behavior, growth, and developmental physiology of S. frugiperda, highlighting its potential as an eco-friendly botanical insecticide.
Red chili pepper (Capsicum annuum) is a high-value horticultural crop in Indonesia, but its production is severely constrained by Aphis gossypii, which can cause yield losses of up to 65%. This study aimed to evaluate the biological characteristics, virulence, and lethal-sublethal effects of local isolates of Beauveria bassiana and Metarhizium anisopliae against A. gossypii. Fungal viability and growth were assessed through spore germination and radial growth assays, while pathogenicity was evaluated using four conidial concentrations (10⁴–10¹⁰ conidia mL⁻¹). Aphid mortality, lethal concentration (LC), lethal time (LT), and reproductive performance were recorded, and the data were analyzed using factorial and probit analyses. The results showed that both fungi exhibited high spore viability (>96%) and stable mycelial growth rates (3.71–3.74 mm day⁻¹). Aphid mortality increased significantly with increasing conidial concentration, reaching 100% at 10¹⁰ conidia mL⁻¹, whereas mortality at 10⁴ conidia mL⁻¹ ranged from 26.67% to 40.00%. Probit analysis revealed comparable virulence, with LC₉₅ values of 8.09 for M. anisopliae and 8.29 for B. bassiana. Lethal time analysis showed a concentration-dependent killing pattern, with B. bassiana acting more rapidly at lower concentrations (10⁴–10⁶ conidia mL⁻¹) and M. anisopliae exhibiting shorter LT₅₀ values at higher concentrations (10⁸–10¹⁰ conidia mL⁻¹). In addition to lethal effects, both fungi significantly suppressed aphid reproduction, particularly at higher conidial concentrations. These findings demonstrate that B. bassiana and M. anisopliae possess strong and complementary bioefficacy against A. gossypii, supporting their potential application in integrated pest management programs.
Wereng batang coklat (WBC) (Nilaparvata lugens Stal) merupakan hama utama yang menyebabkan kerusakan tanaman padi. Varietas padi sangat memengaruhi tingkat serangan WBC. Uji coba perlu dilakukan untuk mengetahui apakah varietas padi dari Kab. Pesisir Selatan tahan terhadap WBC. Penelitian ini bertujuan untuk mengetahui ketahanan beberapa varietas padi lokal asal Kabupaten Pesisir Selatan terhadap serangan WBC. Penelitian menggunakan Rancangan Acak Lengkap (RAL) dengan menggunakan 7 perlakuan dan 4 ulangan. Perlakuan terdiri dari varietas padi lokal Kab. Pesisir Selatan yaitu Sarai Sarumpun, Kutu, Bakwan, Banang Salai dan Bujang Marantau, sebagai pembanding varietas TN1 (rentan) dan IR 74 (tahan). Uji ketahanan varietas padi menggunakan bibit padi berumur 7 Hari Setelah Semai (HSS). Setiap ulangan perlakuan diinfestasikan nimfa WBC instar 2-3. Parameter yang diamati adalah gejala serangan WBC, mortalitas WBC, persentase serangan, dan intensitas serangan. Pengamatan dapat dilihat bahwa padi yang tergolong agak tahan adalah varietas Banang Salai, dengan mortalitas WBC sebesar 83,13%, persentase serangan sebesar 68,75%, dan intensitas serangan sebesar 50,34%. Padi yang tergolong agak rentan adalah varietas Bujang Marantau dengan mortalitas WBC sebesar 49,32%, persentase serangan sebesar 96,26%, dan intensitas serangan sebesar 66,52% serta padi yang tergolong rentan adalah varietas Bakwan dan Kutu, dengan mortalitas WBC sebesar 48,88% dan 46,50%, persentase serangan sebesar 97,5%, dan intensitas serangan sebesar 76,40% dan 76,50 serta padi yang tergolong sangat rentan adalah varietas Sarai Sarumpun dengan mortalitas WBC sebesar 25,94%, persentase serangan sebesar 100%, dan intensitas serangan sebesar 90,52%.
Soft rot is an important potato disease caused by the bacterial pathogen Erwinia carotovora. Although chemical bactericides are commonly used for control, biological control using antagonistic bacteria offers a promising and environmentally friendly alternative. Bacteria capable of surviving in extreme environments have been reported to show high efficiency and the ability to withstand various environmental conditions. This study aimed to isolate, evaluate the potential and activity, and identify the molecular basis of novel bacteria from Sidoarjo hot mud against E. carotovora, the causal agent of potato soft rot. The methods used included sample collection, bacterial isolation and screening, inhibition assays against E. carotovora, soft rot suppression assays on potato tubers, molecular identification using 16S rRNA gene sequencing, and antibiosis mechanism testing. Based on the research, 16 bacterial isolates were obtained, of which four isolates (BLS3, BLS6, BLS7, and BLS10) demonstrated antagonistic activity, as evidenced by the formation of clear inhibition zones on nutrient agar medium. Suppression assays further confirmed their ability to significantly reduce soft rot symptoms in potato tubers. Among these, BLS10 isolate exhibited the highest inhibition and suppression activity, with an inhibition zone of 2.03 cm and a soft rot mass of 0.52 grams. Molecular identification based on 16S rRNA gene sequencing showed that isolates of BLS3, BLS6, BLS7, and BLS10 were identified respectively as Bacillus velezensis, Bacillus methylotrophicus, Bacillus amyloliquefaciens, and Ochrobactrum intermedium. All isolates demonstrated a bacteriostatic antibiosis mechanism, indicated by turbidity in peptone water, suggesting inhibition through secondary metabolite production.
Paracoccus marginatus is one of the important pests that can reduce papaya production. Piper aduncum nanoemulsion has potential as a botanical pesticide to control papaya mealybug (Paracoccus marginatus). This present research was aimed to determine the most effective concentration in suppressing the development of P. marginatus. This study consisted of 6 treatments and 5 replications: 0.33%, 0.43%, 0.57%, 0.75%, 0.99%, and control. The observed parameters were: nymph mortality, adult mortality, daily mortality, adult emergence, LC50, and LC95. The data obtained were analyzed using variance (ANOVA) and 5% Tukey. The LC50, and LC95 value was analyzed using Polo Plus. Piper aduncum nanoemulsion exhibits strong insecticidal activity against nymphs and adults of Paracoccus marginatus under laboratory conditions. Among the concentrations tested, 0.99% was the most effective, causing 81.11% nymph mortality at 72 hours post-application; adult emergence was limited to only 13.33%. The LC₅₀ and LC₉₅ values at 72 hours were 0.506% and 1.222%, reflecting the potency of the nanoemulsion at relatively low doses. Further research under field conditions is recommended to evaluate its efficacy, formulation stability, and safety on non-target organisms.
Bacterial leaf blight (BLB), caused by Xanthomonas oryzae pv. oryzae (Xoo), is one of the most destructive diseases affecting rice, resulting in significant yield losses and reduced grain quality. The overuse of chemical bactericides has raised environmental concerns and contributed to the emergence of resistant pathogen strains, emphasizing the need for sustainable alternatives. Plant Growth-Promoting Rhizobacteria (PGPR) offer a promising alternative due to their dual role in enhancing plant growth and suppressing phytopathogens. This study aimed to isolate and characterize PGPR from the rhizosphere of Imperata cylindrica, a grass species thriving in the extreme sand sea environment of Bromo Tengger Semeru National Park (BTSNP), Indonesia. The sampling site represents a unique volcanic soil ecosystem characterized by sandy texture, high surface temperatures, and nutrient-poor conditions, with no vegetation other than I. cylindrica. These extreme environmental conditions suggest that the associated microbial communities may be highly adapted to abiotic stress and possess valuable traits for plant growth promotion and pathogen suppression. A total of 46 rhizobacterial isolates were obtained, of which five (Isolates 5, 6, 8, 10, and 12) demonstrated nitrogen-fixing ability, phosphate-solubilizing activity, and strong antagonism against Xoo. Morphological, physiological, and biochemical analyses identified Isolates 5, 8, and 12 as Pantoea spp., while Isolates 6 and 10 were classified as Erwinia spp. In vitro inhibition assays revealed that Isolate 6 exhibited the highest antagonistic activity, comparable to streptomycin, and was categorized as "Very Strong." These findings highlight Isolate 6 as a promising candidate for development as a biological control agent for sustainable rice disease management.
The fall armyworm (Spodoptera frugiperda, Lepidoptera: Noctuidae) is an invasive pest that threatens maize production in Indonesia, particularly during the vegetative stage. This study aimed to identify egg parasitoid species and assess their parasitism levels on S. frugiperda during this critical growth phase in Gorontalo, Indonesia. Field sampling was conducted from February to April 2021 using random sampling of egg masses at three maize fields in Suwawa District. The collected eggs were incubated in the laboratory to observe emergence and identify parasitoids. This study revealed the significant contribution of egg parasitoids—particularly Telenomus sp.—in suppressing S. frugiperda populations during the vegetative stage of maize in Gorontalo, Indonesia. Parasitism rates were remarkably high across all observation periods, ranging from 83.82% to 92.54%, and the emergence of Telenomus sp. consistently exceeded that of Trichogramma sp. These findings demonstrate that native egg parasitoids are already actively controlling S. frugiperda in the field and should be preserved through ecologically sensitive pest management. Avoiding insecticide use during early maize growth stages is essential to maintaining the activity of beneficial parasitoids.
The brown spot disease (BSD) caused by Helminthosporium oryzae in rice can lead to yield losses of up to 45 %. Using endophytic bacterial consortia as a biological agent is one of the most potential control methods for resisting the disease. This study aimed to obtain an endophytic bacterial consortium with the best efficacy in controlling BSD and its ability to enhance rice plant growth. Statistical analysis in this study was made using Analysis of Variance (ANOVA) with Duncan’s Multiple Range Test (DMRT) in a randomized experimental design comprising five treatments with five replications. The treatments included: A (Serratia marcescens ULG1E4 + S. marcescens JB1E3), B (S. marcescens ULG1E4 + S. marcescens JB1E3 + Serratia marcescens JB1E2), C (Bacillus sp. SJI + Serratia marcescens ULG1E4), D (positive control), and E (negative control). Testing was conducted in planta, with the introduction of the bacterial consortium (10⁸ cells/mL) via seed and root soaking methods. Subsequently, the leaves of 30-day-old rice plants were inoculated with H. oryzae by spraying a conidial suspension of 10⁶ conidia/ml. Parameters observed included disease progression (incubation period, incidence, and severity), seedling growth metrics (height, leaf number, root length, fresh and dry biomass), and overall plant development (plant height, leaf number, and tiller count). The results demonstrated that the consortium of Serratia marcescens ULG1E4, Serratia marcescens JB1E3, and Serratia marcescens JB1E2 effectively controlled BSD, achieving a 53.69% reduction in disease severity and promoted rice plant growth, evidenced by a 30.63% increase in leaf number
Root-knot nematodes (RKN), especially Meloidogyne incognita, are one of the most damaging and widespread plant-parasitic nematodes (PPNs) in cultivated plants worldwide. The intensive application of chemical nematicides in controlling these pests raises environmental and ecological concerns, prompting the need for sustainable alternatives. This study aimed to isolate and evaluate the predatory potential of indigenous nematode-trapping fungi (NTF) from the rhizosphere soils of healthy tomato plants against M. incognita under in vitro conditions. Soil samples were processed using the soil sprinkle technique, and fungal isolates capable of forming traps were screened by exposing them to second-stage juvenile (J2) of M. incognita. This study isolated 20 nematophagous fungi that have antagonistic activity against M. incognita from the rhizosphere soil of tomato plants. Among these, four isolates were identified as nematode-trapping fungi, with TRK 04 showing the highest predation efficacy, followed by TRK 07, TRK 09, and TRK 16. All four isolates were identified as part of the Arthrobotrys genus. These findings highlight the potential of indigenous nematophagous fungi as sustainable biocontrol agents for managing root-knot nematodes. Their application could support the development of environmentally friendly agricultural practices and reduce reliance on chemical nematicides. Further, in vivo studies are recommended to validate their efficacy under field conditions.
Rhizobacteria is bacteria that found in the root zone of plants. Rhizobacteria can act as biocontrol agents against Fusarium fujikuroi, the fungus that causes bakanae disease in rice plants. This study aimed to obtain rhizobacteria isolates from the roots of rice plants and to determine their characteristics as biocontrol agents against F. fujikuroi in vitro. This research consisted of two stages: 1) Exploration of rhizobacteria from the roots of rice plants in Padang City, West Sumatera, Indonesia and 2) Antagonistic character of Rhizobacteria against F. fujikuroi in vitro including: antagonistic test, hydrolytic enzyme production test (protease, amylase, and chitinase), and HCN compound production test. Based on the research, 32 rhizobacterial isolates were obtained as candidates for biological agents. All rhizobacterial isolates can suppress the growth of Fusarium fujikuroi in vitro with an inhibition percentage of 19.43-73.53%. The 4 best isolates in suppressing the growth of Fusarium fujikuroi are Kr 2.2 from Kuranji, KG 2.2 from Korong Gadang, PA 2.1 and PA 1.2 from Pasar Ambacang with an inhibition percentage of 60.39-73.53%. The four isolates are also able to produce hydrolysis enzymes (protease, amylase and chitinase) and HCN compounds
The coconut beetle, Brontispa longissima (Coleoptera: Chrysomelidae), is a serious pest of coconut trees, where the larvae and adults feed on coconut leaves. This activity produces vibrations that can be detected by acoustic equipment. This study aimed to identify the sound features between larvae and adults using temporal and spectral acoustic detection. Insect samples were collected from infested coconut trees in May 2021 in Penang, Malaysia. Acoustic recording activities were carried out at the Applied Entomology Laboratory using an AED-2010 sensor-preamplifier module. Parameters such as average impulse time, number of impulses, and average activity rate were recorded to examine the temporal aspect. Two parameters used in the spectral analysis were frequency range and dominant frequency (kHz). An Independent two-sample T-test was conducted to compare the mean differences in acoustic parameters between adult and larvae of B. longissima. The results showed that adult B. longissima was more active than larvae. It had higher mean impulse interval time (ms), mean number of impulses, and mean activity rate (impulses/s) than the larvae. However, the results showed that the difference in activity between larvae and adults was insignificant. Furthermore, this acoustic study is critical to understanding the behavior of destructive insects and helps develop more curative and sustainable methods to control B. longissima. Using acoustic methods could assist in evaluating the level of infestation and damaging activity of the insect pest
