Cassava mosaic disease (CMD) remains a major constraint to cassava (Manihot esculenta Crantz) production in Cameroon. This study aimed to generate updated epidemiological data on CMD across the country. Surveys were conducted in 342 fields across the ten administrative regions of Cameroon between January and September 2022, following a standardized protocol adopted by all fourteen countries participating in the Central and West African Virus Epidemiology for Food Security (WAVE) program. In each field, 30 plants were assessed for CMD incidence, severity, whitefly population, and mode of infection. CMD symptoms were observed in all ten regions. The overall mean CMD incidence was 54.72%, with a mean severity score of 2.39. Incidence, severity, and whitefly populations varied significantly among regions. The South Region recorded the highest mean incidence (74.34%), while the Far North had the lowest (18.97%). The Adamawa Region exhibited the highest mean severity (2.63), whereas the South West Region had the lowest (2.19). Whitefly abundance per plant was greatest in the South West (21.44) and lowest in the Far North (0.40). PCR amplification and sequencing confirmed the presence of cassava mosaic geminiviruses (CMGs) in leaf samples. A positive correlation was detected between mean whitefly abundance and CMD incidence, while altitude was negatively correlated with whitefly numbers. Both CMD incidence and whitefly populations were higher in intercropped fields than in monocropped fields. Notably, intercropping cassava with maize reduced whitefly populations, while intercropping with sweet potato lowered CMD incidence. The primary source of CMD infection was the use of infected cuttings. These findings provide valuable insights for the development of targeted interventions and improved management strategies for CMD in Cameroon.

The most economically important invasive thrips species, known for causing serious damage to various crops through feeding and virus transmission, was recorded in the cut flower production center of West Java Province, Indonesia. Thrips specimens were collected from chrysanthemum plastic houses using sweep nets, beating trays, yellow pan traps, and hand vacuums. Based on morphological characteristics, the specimens were identified as Frankliniella occidentalis Pergande 1895 (Thysanoptera: Thripidae). Infestation levels in chrysanthemum ranged from 9 to 15 individuals per plastic house. This is the first confirmed report of F. occidentalis infesting chrysanthemums in Indonesia, as the species has not been previously recorded in the country. It can be distinguished from other thrips species by its unique morphological traits, including comb-like setae on the eighth abdominal tergite and distinctive chaetotaxy patterns on the head and pronotum.

Banana bunchy top disease has become increasingly important in South Sumatra. The disease, caused by Banana bunchy top virus (BBTV), leads to severe losses as infected plants fail to produce fruit. The virus is transmitted in a persistent manner by banana aphid, Pentalonia nigronervosa. Both nymphs and adults of the aphid can transmit the virus, with adults being more efficient vectors than nymphs. The threat of the disease in the province has been escalating, as indicated by the significant rise in the number of infected banana plants in the recent years. However, no epidemiological study had been conducted prior to this research. This study aimed to identify and evaluate the contributing factors to the epidemic of banana bunchy top disease in South Sumatra. A survey was conducted to assess the banana cropping system and all aspects contributing to the disease’s epidemiology in the province. Thirteen regencies were surveyed using a purposive sampling method, covering 11 regencies and 3 cities selected based on the accessibility of banana plantations by transportation routes. In each site, banana plants within an imaginary 50-meter diameter circle centered on an infected plant were sampled. The result showed that the BBTV epidemic was influenced by several factors: (1) banana genome, with diploid AA and triploid AAA cultivars being more resistant than those containing the B genome; (2) cropping system, with higher disease prevalence in mixed-cropping systems than in monoculture; (3) botanical environment, where the presence of alternative hosts of P. nigronervosa correlated with higher disease incidence; (4) farmer behavior, with lack of concern or action against the disease contributing to its spread; and (5) transportation access, with higher incidence observed in areas closer to roads.

Bacterial Leaf Blight (BLB), caused by Xanthomonas oryzae pv. oryzae, is a major threat to global rice production, causing yield losses of up to 80%. Accurate assessment of disease severity is essential for developing resistant rice varieties and implementing effective management strategies. However, traditional visual observation methods, while widely used, are prone to subjectivity and reduced accuracy. This study evaluates the accuracy of image analysis for assessing rice plant resistance to BLB. Disease severity was assessed using both visual observation and image analysis, with results quantified through the Area Under the Disease Progress Curve (AUDPC) and infection rate calculations. Image analysis outperformed visual observation, achieving an accuracy rate above 96%, compared to less than 90% for the latter. The Ciherang variety demonstrated greater resistance to BLB, with lower AUDPC and infection rates when assessed using image analysis. Conversely, visual observation produced contradictory results, highlighting its limitations. This study concludes that image analysis provides a more objective, reproducible, and accurate approach to assessing disease severity, with implications for breeding programs and integrated disease management systems. Further research is recommended to validate these methods across a broader range of rice genotypes and environmental conditions.

Ralstonia syzigii subsp. indonesiensis (Rsi) is a causal pathogen of Phylotype IV within the Ralstonia solanacearum species complex, commonly found in chili plants. This pathogenic bacterium uses a quorum sensing (QS) mechanism that relies on N-acyl homoserine lactone (AHL) signals to regulate the expression of virulence genes, such as those encoding exopolysaccharides (EPS). Biological control of Rsi can be achieved by disrupting its QS system. The aim of this study was to isolate AHL-lactonase-producing bacteria, analyze the genetic diversity of their aiiA gene, and evaluate their effectiveness in suppressing EPS production in Rsi. The research involved sampling, isolating, and screening bacterial candidates from chili plants as AHL-lactonase producers using bioassays and molecular techniques, followed by evaluation of their ability to inhibit EPS expression as a virulence factor of Rsi. Bacterial samples were isolated from Brebes, Bandung, and Garut Regencies. Molecular identification revealed that the twelve selected isolates belonged to the genus Bacillus. Sequencing results showed genetic diversity in the aiiA gene among isolates obtained from regions with different altitudes. All isolates demonstrated the ability to suppress Rsi virulence factors.

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.

Maize downy mildew, caused by Peronosclerospora spp., is a major disease affecting maize cultivation in tropical regions, particularly in Indonesia. One potential control strategy is the induction of plant resistance. Previous studies have demonstrated that benzoic acid (BA), a non-fungicidal chemical compound, can induce maize resistance against downy mildew. Induced resistance mechanisms do not directly inhibit pathogen development but enhance the plant’s defensive response to infection. This study utilized various maize lines, ranging from susceptible to resistant, to evaluate the impact of BA-induced resistance on photosynthesis rate and chlorophyll content as the key agronomic parameters associated with the plant growth. The results showed that BA treatment did not significantly increase the photosynthetic rate and chlorophyll content in moderately resistant and resistant maize lines. However, in susceptible and moderately susceptible lines, BA treatment enhanced both parameters, indicating its role in strengthening plant resistance. These findings suggest that resistant maize lines do not respond to BA induction, whereas susceptible and moderately susceptible lines benefit significantly from its application. This provides new insight that BA can potentially induce resistance in susceptible maize plants against downy mildew.

Fruit flies (Diptera: Tephritidae) are major pests in the horticultural sector. However, comprehensive information on their distribution across different habitats in Central Sulawesi is still lacking. This study aimed to assess the species diversity of fruit flies in three habitat types—urban, agricultural, and forest areas—in Central Sulawesi, Indonesia. Collections were conducted from November 2022 to May 2023 using Steiner traps baited with cue lure (CUE) and methyl eugenol (ME). Fruit fly specimens were identified to the species level, and diversity, dominance, and evenness indices were calculated. A total of 32 species and 10,393 individual fruit flies were collected across the three habitat types. The forest habitat exhibited the highest diversity and evenness indices, followed by agricultural and urban areas. In contrast, the urban habitat showed a higher dominance of certain species. The most dominant species were Bactrocera dorsalis (ME trap) and B. albistrigata (CUE trap). Notably, the presence of rare species found exclusively in forest habitats contributed significantly to the higher species richness observed there.

Rhizoctonia solani Kühn is a pathogenic fungus that causes sheath blight disease in rice. One effective strategy for managing this disease is the use of biological control, particularly through consortia of endophytic bacteria. This study aimed to identify the most effective endophytic bacterial consortium for suppressing sheath blight severity while also enhancing rice growth and yield. A Completely Randomized Design (CRD) was aemployed with six treatments, three replications, and three experimental units per treatment. The treatments included four bacterial consortia composed of combinations of Bacillus thuringiensis LmD13, Ochrobactrum intermedium LmB1, and Stenotrophomonas maltophilia LmB35, along with positive and negative controls. The experiment involved treating rice seeds and soaking seedling roots with the bacterial consortia before transplanting. R. solani was inoculated onto the rice leaf sheaths 40 days after planting. The effectiveness of each consortium as a biocontrol agent was evaluated based on incubation period, disease incidence, disease severity, and the area under the disease progress curve (AUDPC). Their biostimulant potential was assessed through parameters related to seedling growth, plant development, and yield. Results indicated that the endophytic bacterial consortia effectively suppressed sheath blight and significantly improved rice growth and production. Notably, the consortium of B. thuringiensis LmD13, O. intermedium LmB1, and S. maltophilia LmB35 extended the incubation period to 35 days post-inoculation and reduced disease incidence, severity, and AUDPC to 22.22%, 0.29%, and 1.01, respectively. This consortium also enhanced rice yield, with fresh and dry grain weights reaching 72.78 g and 63.02 g, respectively, compared to the positive control. These findings suggest that this bacterial consortium holds strong potential as a biocontrol agent and yield enhancer in rice cultivation.

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.