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Wood-feeding termites and wood-decaying fungi share a niche and likely interact, impacting wood degradation processes. Prior research has primarily examined termite the preferences for decayed wood species, revealing instances of termite feeding deterrence in response to fungal decay products. The compound that caused the deterrence effect was extracted and studies regarding the suspected compound and its toxicity has been previously conducted. In this study, further observation of the extract retention and concentrations were asessed against Reticulitermes speratus. Result indicated that the decayed wood extract retains its deterrent activity for up to four days post-application, with a peak effect observed within the initial hours. Furthermore, the concentration of the extract correlates with both feeding deterrence and termite mortality, suggesting a concentration-dependent relationship. Results show a significant decrease in feeding and increase in mortality with longer exposure durations, indicating sustained deterrent activity for up to four days. Higher extract volumes correlate with reduced feeding and increased mortality, supporting concentration-dependent deterrence. Highest mortality was observed after 24 hours of exposure, suggesting continued toxicity despite diminished deterrence.

Soil salinity is a major limiting factor for crop productivity, which increases continuously due to climate change. This barrier can possibly be overcome with the occurrence of halotolerant endophytic bacteria which reportedly plays an important role in protecting plants against various environmental stresses. Therefore, plant growth-promoting microbes are used in agriculture as an inexpensive and eco-friendly technology to enhance crop productivity in saline areas. In this study, the three isolates with nitrogen fixation ability were applied for mitigation of salt stress. The isolates were coded as C3A1, C8D2, and K10P4 and applied to rice plants by seed priming method. Furthermore, they were given as single innoculant or combined as a consortium compared to control, which was without the addition of endophytic bacteria, while the inoculated seed was planted on saline semisolid Fahraeus media at 4 dS m−1. The results showed that the single isolate of K10P4 endophytic bacteria increased the dry weight of rice plants, N uptake, and chlorophyll of plants in saline conditions. The combination of K10P4 isolate with C8D2 was synergistic and increased the population of endophytic bacteria in root tissue and chlorophyll content compared to the combination of C3A1 or three isolates. Meanwhile, the use of the 16S ribosomal RNA method on C3A1, C8D2, and K10P4 indentified the isolates as Ochrobactrum tritici (C3A1), Pseudomonas stutzeri (C8D2), and Pseudomonas stutzeri (K10P4).

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Rice field soil quality in Rancaekek decreases gradually due to textile waste water to irrigation source. One of the heavy metal contaminant is chrome (Cr). As an effort to reduce Cr residue, bioagent-added organomineral nitrogen (abbreviated as BaON) fertilizer consisted of the mixture of urea, zeolite, activated charcoal, and plant compost enriched with bioagent (Bacillus subtilis) was added as a slow release fertilizer. This paper studied the effect of BaON fertilizer formulation towards total nitrogen content, pH and total Cr content in Rancaekek paddy soil. The experiment was designed in Randomized Block Design with six treatments and five replicates, consisted of: 0 (control), 150; 200; 250; 300; and 350 kg ha-1. The result showed that the application of BaON fertilizer increased soil total nitrogen content and pH, and decrease Cr residue in Rancaekek paddy field soils. Application of 350 kg ha-1 of BaON fertilizer gave the highest increase of total nitrogen in 60 days after transplant (0.11%), while 300 kg ha-1 of BaON gave the highest increase in pH (6.18), and the application of 250 kg ha-1 of BaON gave the highest reduction of chrome (16.15 mg kg-1) in Rancaekek soils. This study suggests that application of Urea-zeolite-activated charcoal and bio-agent inoculated compost application could minimize Cr contaminated waste in the long-run. [ABSTRACT FROM AUTHOR]

Saline soils can be developed for the cultivation of food crops such as rice. Despite offering this potential, the utilisation of saline soils is limited by its physical, chemical and biological properties. These barriers can be amended through the application of azolla compost and biofertilisers. In this research, combinations of azolla compost and biofertiliser consortia were assessed to identify the best treatment for rice plants grown in soil at various salinity levels. showed that the application of azolla compost and biofertiliser increased the phosphate solubilising bacteria (PSB) population and the dry weight of rice dry cultivated in a saline soil. The salinity treatment of 2-6 mm hos cm-1 influenced PSB population and rice dry weight. An ncreasing level of salinity decreased PSB population and rice dry weight. [ABSTRACT FROM AUTHOR]

Arbuscular mycorrhizal fungi (AMF) play a significant role in enhancing soil health, nutrient uptake and availability in soils. This research aimed to determine the status of indigenous AMF on an intensively cultivated agricultural soil ecosystem (chili rhizosphere) and a natural forest ecosystem in Garut district, well known as a central chili producer in West Java. High tillage of agricultural soil may lead to destruction of the soil microbial community in general, therefore a forest ecosystem representing an untilled natural soil was used as a comparison Soil sampling was done in transects with the length of an ordinate point in every 100 m on chili cultivated areas and in the natural forest soil ecosystem of Gunung Putri. Five composite soil samples (0-20 cm depth) from each ecosystem were taken based on coordinate points. The number of indigenous AMF spores and roots colonisation was determined and mycorrhiza species were identified using a molecular analysis of the AMF DNA. The research results revealed that number of AMF spores in the chili rhizosphere soil was greater than in the natural forest soil. However, the degree of mycorrhizal colonisation in the rhizosphere under both ecosystems was not significantly different. The indigenous Glomus etunicatum was identified to be the dominant species in both soil ecosystems. Further research needs to investigate the potential of this indigenous AMF that could develop as biofertilizer for cultivation of chili. [ABSTRACT FROM AUTHOR]

Illegal gold mining and the resulting gold mine tailing ponds on Buru Island in Maluku, Indonesia have increased Mercury (Hg) levels in agricultural soil and caused massive environmental damage. High levels of Hg in soil lowers plant productivity and threatens the equilibrium of the food web. One possible method of handling Hg-contaminated soils is through bioremediation, which could eliminate Hg from the rhizosphere (root zone). In this study, indigenous fungi isolated from Hg-contaminated soil exhibited Hg-resistance in vitro. Soil samples were collected from the rhizosphere of pioneer plants which grew naturally in areas contaminated with gold mine tailing. The fungi's capacity for Hg-resistance was confirmed by their better growth in chloramphenicol-boosted potato dextrose agar media which contained various HgCl2 concentrations. Four isolates exhibited resistance of up to 25 mg kg-1 of Hg, and in an experiment with young Chinese cabbage (Brassica rapa L.) test plants, two fungi species (including Aspergillus) were demonstrated to increase the soil's availability of Hg. The results suggest that Hg-resistant indigenous fungi can mobilize mercury in the soil and serve as potential bioremediation agents for contaminated agricultural land. [ABSTRACT FROM AUTHOR]

Brown rot fungus Fibroporia radiculosa (Peck) Parmasto grown in decayed wood and non-wood material, potato dextrose agar (PDA) media, deterred Reticulitermes speratus (Kolbe) feeding. Decayed wood and PDA media were extracted and tests were performed to assess termite feeding behavior towards the extracts. We found that the extract from PDA media also suppressed termite feeding, although it did not induce mortality. Using gas chromatography and mass spectrometry analysis, two bioactive compounds were detected from the decayed wood extract, and one was detected from the PDA extract. Based on National Institute of Science and Technology (USA) Mass Spectral library match and compound fragmentation, both of the compounds belong to the sesquiterpenes family.

No-choice feeding tests using ethanol, chloroform, and acetone extractives of teak ( Tectona grandis ) heartwood clearly showed feeding deterrent activity and toxicity to the subterranean termite Reticulitermes speratus . The amount of 2-methylanthraquinone (MAQ) in teak wood extractives was not related to the feeding deterrents or toxicity, as shown by the no-choice feeding tests conducted using crude extractives containing various amounts of MAQ, MAQ alone, and fractions of crude extractives. As a native pest, the subterranean termite Coptotermes formosanus was more tolerant to the fractions of crude extractives than Reticulitermes speratus , and the mortality observed in C. formosanus was not due to the presence of MAQ., Competing Interests: The authors declare no conflict of interest.

We found that decayed wood stakes with no termite damage collected from a termite-infested field exhibited a deterrent effect against the termite Reticulitermes speratus, Kolbe, 1885. The effect was observed to be lost or reduced by drying. After identification, it was found that the decayed stakes were infected by brown rot fungus Fibroporia radiculosa (Peck) Parmasto, 1968. In a no-choice feeding test, wood blocks decayed by this fungus under laboratory condition deterred R. speratus feeding and n-hexane extract from the decayed stake and blocks induced termite mortality. These data provided an insight into the interaction between wood-rot fungi and wood-feeding termites., Competing Interests: The authors declare no conflict of interest.