Jurnal Hama dan Penyakit Tumbuhan Tropika

Efficacy of phosphonic acid applied by spraying and seed treatment at various concentrations for controlling downy mildew disease in maize

2025-09-01T08:09:25+00:00

Downy mildew, caused by Peronosclerospora spp., is one of the major problems in maize cultivation. Several studies have reported the development of resistance in Peronosclerospora spp. to metalaxyl, which had previously been an effective control method for the disease. Other research suggests that the efficacy of phosphonic acid in controlling downy mildew in maize is inconsistent. The objective of this study was to evaluate the efficacy of seed treatment with phosphonic acid in controlling downy mildew in Bisi 18 maize. The treatments were arranged in a randomized block design with six replications. The observed variables included the incidence and severity of the disease, the area under the disease progress curve (AUDPC), maize yield, and the content of tannin and hydroquinone compounds in maize leaves. The results showed that both phosphonic acid applied by spraying and seed treatment significantly reduced the incidence and severity of downy mildew (P < 0.05). However, the concentrations of phosphonic acid used in seed treatment had no significant effect on the disease during 1–7 weeks after inoculation. Furthermore, all phosphonic acid treatments tended to increase the content of tannin and hydroquinone compounds in maize leaves, which should be confirm quantitatively.

Insecticide application effect on ground dwelling arthropods in edamame crops

2025-07-18T06:47:11+00:00

Ground-dwelling arthropods play many important roles in agroecosystems. This experiment was conducted to assess the effects of botanical and synthetic insecticides on soil arthropods in edamame crops. The study included six treatments: soursop leaf extract at concentrations of 1% and 2%, diflubenzuron at concentrations of 0.05% and 0.1%, a common synthetic insecticide (chlorantraniliprole 0.15%), and a control (untreated plants), each with three replications. Pitfall traps were used to sample soil arthropods. A total of 2222 soil arthropods were collected, consisting of 1443 (64.94%) predatory arthropods and 778 (35.06%) detritivorous arthropods. The dominant orders of predators and detritivores were Araneae (61.5%) and Coleoptera (40.2%), respectively. The highest numbers of predatory and detritivorous arthropods were found on edamame plants sprayed with soursop extract, while the lowest numbers were recorded on plants treated with the common synthetic insecticide chlorantraniliprole. These results indicate that chlorantraniliprole negatively impacts the presence of ground-dwelling arthropods in edamame agroecosystems. In contrast, the application of the botanical insecticide (soursop leaf extract) and the synthetic insect growth regulator (diflubenzuron) did not reduce the abundance or diversity of ground-dwelling arthropods in edamame fields.

Application of biocontrol products Bio P60 and Bio T10 as single or in combination in suppressing chili fruit anthracnose in the field

2025-07-11T06:56:57+00:00

This study aimed to evaluate the effectiveness of single or combined applications of Bio P60 and Bio T10 products in suppressing anthracnose disease in chili pepper under field conditions. The research was conducted at an altitude of 1200 m above sea level using a randomized block design with five treatments: control, chemical fungicide, Bio P60, Bio T10, and a combination of Bio P60 and Bio T10, each replicated five times. Observed variables included incubation period, disease incidence, disease intensity, area under disease progress curve (AUDPC), infection rate, plant height, number of leaves, time of first flower, time of first fruit, number of fruits, fruit weight per plant, harvest weight per plot, and qualitative phenolic compound content. The results showed that the combined application of Bio P60 and Bio T10 was the most effective, delaying the incubation period, suppressing disease intensity, and reducing AUDPC by 13.71%, 69.34%, and 47.06%, respectively, compared to the control. The combination treatment also enhanced plant growth and yield, increasing plant height, number of fruits, fruit weight per plant, and harvest weight per plot by 27.38%, 62.65%, 90.85%, and 82.99%, respectively. Furthermore, the application of Bio P60, Bio T10, and their combination increased phenolic compound content qualitatively in chili pepper plants.

The Impact of organic amendments (vermicompost and fermented cow manure) on managing corn stalk rot disease caused by Fusarium incarnatum

2025-03-29T21:49:01+00:00

This study investigated the efficacy of organic amendments, specifically vermicompost (V) and fermented cow manure (C), at application rates of 625 and 1250 kg/dunam, in managing corn stalk rot disease caused by Fusarium incarnatum. Maize (Zea mays L.) is a globally vital crop, making the study of its diseases, such as stalk rot, essential for ensuring food security. Field experiments were conducted on five hybrid corn varieties (DKc6664, DKc6777, GS235982, GS235772 and 2341.Rayal) during the spring season of 2024 in Baghdad, Iraq. The results demonstrated that higher application rates (V. 1250 and C. 1250) significantly reduced disease severity and improved plant growth parameters, including plant height, vegetative mass, and yield components. Vermicompost at 1250 kg/dunam (V. 1250) was particularly effective in reducing disease severity in DKc6664 (16.67%) and DKc6777 (16.67%), while fermented cow manure at 1250 kg/dunam (C. 1250) enhanced root development and seed weight in DKc6777. In contrast, F. incarnatum inoculation consistently increased disease severity across all varieties, with the highest severity observed in GS235982 (91.61%). These findings highlight the potential of organic amendments, especially at higher application rates, to improve corn productivity and manage stalk rot disease, even under pathogen pressure.

Identification and sensitivity testing of whip smut pathogen on sugarcane to fungicides and plant extracts

2025-03-13T04:24:06+00:00

Whip smut symptoms have emerged in sugarcane plantations in Central Lampung Regency, Lampung Province. However, the identity of the pathogen and its sensitivity to various fungicidal active ingredients remain unclear. This study aims to identify the whip smut pathogen in sugarcane plantations in Central Lampung Regency and evaluate its sensitivity to different fungicidal active ingredients.The research involved morphological and molecular identification of the pathogen, along with sensitivity testing against fungicides containing carbendazim, prochloraz, and mancozeb, as well as plant-based fungicides derived from puyangan (Zingiber zerumbet) and jamuan (Curcuma zedoaria) extracts. Morphological analysis revealed that the whip smut pathogen has septate hyphae, cylindrical sporidia measuring 7.45–18.31 µm in length and 1.63–3.89 µm in width, and round, yellowish-brown teliospores with an average size of 6.39 × 6.66 µm. Molecular identification confirmed that the LA UKN isolate from Central Lampung Regency belongs to Sporisorium scitamineum, with a bootstrap value of 93%. Sensitivity testing indicated that the pathogen is highly susceptible to carbendazim and prochloraz but less sensitive to mancozeb, puyangan extract, and jamuan extract.