Isolation of phosphate-solubilizing rhizosphere fungi from jabon merah (Neolamarckia macrophylla) stand of Sidrap Provenance, South Sulawesi

Phosphate is an essential macro element that has a necessary function as a constituent of ATP and DNA in plants. However, the availability of dissolved phosphate in the soil is minimal because it tends to bind with soil minerals to form phosphate complexes. With rhizosphere fungi, the low available phosphate in the soil can be overcome. This study aimed to determine the character and potential of fungi capable of dissolving phosphate. The source of the isolates used was a collection of rhizosphere fungus isolates under the red jabon stand. Purification was carried out using the point method on PDA media. The phosphate dissolving ability test was done using the standard method using liquid pikovskaya media and then analyzed descriptively and quantitatively. Eighteen rhizosphere fungus isolates were observed, two of which could dissolve phosphate, respectively, obtained from isolates JCS16 with a concentration value of 10.48 ppm, JCS 13 with a concentration value of 10.06 ppm.

Organic matter and mixed biofertilizer for plant growth and yield of shallot grown in fertile soil

Nowadays, shallot is important horticultural crops in Maluku include in Tual City, Maluku Province. For ensuring the macronutrients level in soil and yield during shallot cultivation, fertilization composed of chemical, organic and bio fertilizer is needed. The objective of field experiment was to evaluate the effect of mixed biofertilizer integrated with organic matter on total nitrogen and available phosphorous in soil as well as shallot yield grown in Vertisols of Tual. The experiment was setup in randomized block design with four treatments of compost and chicken manure amendment with and without biofertilizer containing N-fixing bacteria and P-solubilizing. At the vegetative stage, consortia biofertilizer combined with either compost or chicken manure increased plant height and soil reaction but decreased the available phosphate (P) and didn't change nitrogen (N) total in soil. Chicken manure amendment combined with biofertilizer inoculation increased dry weight of shoots and bulbs even though didn't significantly differ with other treatments. Nonetheles, that treatment resulted in high yield of shallot bulbs up to 14 t/ha.

Influence of Different Wax Hardening Agents on Surface Roughness of Refractory Cast Investment Materials

Background: Phosphate-bonded investments produce a refractory cast model with rough surface and undesirable properties. Dental Surface hardening agents are then applied to refractory investment materials to enhance its properties. Purpose: compare and evaluate the effects of different dental cast hardening agents (Bees wax, Carnauba wax, and Ceresin wax) on surface roughness of refractory model investment material. Approach: 30 specimens were constructed from commercially available phosphate bonded investment material. Specimens were subjected to a roughness test before dipping in handing agents, then divided into three groups according to the type of wax in which they were dipped. (10 specimens for each type). Surface roughness test was done by a profilometer where three readings were taken for all the specimens' surfaces randomly. The mean was then extracted for the roughness values before and after dipping in waxes. Results: the mean and standard deviation were tabulated and statistically analyzed using students T- test. The roughness values were decreased after the specimens were dipped in waxes (P value < 0.001 HS highly significant). Conclusion: The dipping process with hardening agents has significantly improved the surface roughness of the specimens' investment materials.

Study of Sea Surface Temperature (SST), Does It Affect Coral Reefs?

HighlightEffect of sea surface temperature on coral reefsCorrelation with NOAA and AQUA MODIS satellite imagery dataSea water quality analysisThe adaptability of coral reefsAbstractThis research aims to identify the influence of Sea Surface Temperature (SST) to coral disease and bleaching using MODIS-Aqua data from 2003-2009 and NOAA Coral Reef Watch data. Field-data collection on coral disease and bleaching was carried out in Bunaken National Park, Wakatobi National Park, and Raja Ampat, in August, October, and November 2009, respectively. The presence of coral disease and bleaching was observed by using time-swim method. A prevalence formula was used to calculate the percentage of coral disease and bleaching colonies. The range of mean SST value from each location: Bunaken from 26.84-31.45oC, Wakatobi from 26.09-31.95oC and Raja Ampat from 27.72-31.36oC. There is an influence of SST anomaly on the presence of dis- ease and coral bleaching. During 2003-2019, the highest SST anomaly that could increase the risk of the coral bleaching phenomenon was found in 2010. Coral disease and bleaching were found at locations with high SST anomaly, low nitrate and available phosphate. However, high SST anomalies were not a main cause of coral disease and bleaching. In many locations in Indonesia, mass-bleaching has occurred and the ability of coral adaptation is the main key in dealing with this phenomenon.

Effect of Soil Particle Sizes on Determination of pH, Oxidizable Organic Carbon and Available Phosphate

Soil analysis is integral part of present agricultural farming, where soil samples are particularly determines with 2 mm sieved soil. It is highly related that finer particles pass through 80 mesh (0.2 mm) size had better interaction with concentrated chemical solution or extractant. Total 136 number of soil sample were collected from different agricultural land of Terai region of West Bengal to conducted the study on effect of soil particle sizes passes through 20 mesh (2 mm) and 80 mesh (0.2 mm) sieve on soil pH, oxidizable organic carbon and available phosphate. Thus, each sample was portioned into two particle size classes. Such as ‘80 mesh soil particles’ and ‘20 mesh soil particles’. The pH, oxidizable organic carbon (OCC) and available phosphate contents of two particle sizes of each soil sample were determined and compared. The maximum difference of 0.2 unit was recorded in case of pH analysis with both sieve sizes. The mean organic carbon content of soil particles that passed through 20 mesh 80 mesh sieve was 0.674 and 0.683 respectively, which further signifies organic carbon content value of 80 mesh soil particle size was slightly greater than that of 20 mesh soil particle size. The value of P content by different sieve size had maximum difference 0.2 kg P2O5 ha-1 and for some soils there was no difference. The difference mean of phosphate values of two particle sizes was 0.134 only. This difference is neglected for crop production. Thus, soil sieved through two sieve sizes 20 mesh 80 mesh sieve had no effect with soil pH, little influence on OCC and negligible effect on available phosphate content.

Soil chemical properties of suboptimal dryland in subdistricts of Panji, Kendit, and Kapongan Situbondo Regency for development of cassava (Manihot utilissima L.) cultivation

Cassava has an important role as a potential caloric source for the community. Cassava has been known as a plant with wide range adaptability, thus it is very potential to be cultivated in areas with highly variated agro-ecological conditions such as temperate regions, marginal land, and dryland. This research aimed to study the chemical properties of suboptimal dryland in Panji, Kendit and Kapongan Subdistrict, Situbondo Regency for the development of cassava cultivation. The research was carried out by doing surveys and taking soil samples of suboptimal dryland in Subdistricts of Panji, Kendit, and Kapongan. Each subdistrict had 5 locations chosen as site obtaining soil samples. The soil samples were taken at a depth of 20 cm, each soil sample was put into a plastic clip, then was labeled and brought to the Soil Fertility Laboratory for analysis of soil chemical properties. The soil chemical properties analyzed were pH H2O, cation exchange capacity (CEC), organic carbon, total Nitrogen, available Phosphate, and available Kalium. The results showed that the organic carbon, total Nitrogen, and available Phosphate became a limiting factor which belonged to the category of very low to low, with organic carbon of 0.80-1.44%, total Nitrogen of 0.12-0.17% and available Phosphate of 15.21-15.97 ppm. Nevertheless, the soil chemical properties of suboptimal dryland are quite suitable for cassava, however other inputs are needed to the soil by fertilizing the organic matter, Nitrogen, and Phosphate.

EFFECT OF ADDITION OF VERMICOMPOST, BIO AND MINERAL FERTILIZER ON THE AVAILABILITY OF SOME NUTRIENTS IN SOIL AND POTATO YIELD

A nitrogenous bio-fertilizer comibination was prepared contain Azospirillum lipoferum, and Azotobacter chroococcum bacteria. A phosphate bio-fertilizer consisting of Bacillus megaterium and Glomus mosseae fungus was also prepared. vermicompost was produced from earthworms imported from Iran and others isolated locally. A factorial experiment was carried to evaluate the effect of the interaction between these combinations and vermicompost types under levels of 0%, 25% and 50% of NPK. The results showed a significant superiority of the bio-fertilizer (nitrogen and phosphate) treatment in available nitrogen in the soil after harvest, number of tubers, yield per plant , and the total yield with 39.70 mg N kg -1, 11.03 tuber plant -1, 1367.40 g plant-1, and 43.76 Mg ha-1 respectively. While phosphate bio fertilizer treatment giving available phosphorus in the soil by 22.74 Mg P kg -1 , vermicompost produced from imported earthworms was superior in giving available phosphate in the soil with value 22.74 mg p kg -1 . While the tri interaction was superior for all studied characteristics.

Phosphate dynamics in a sub-tropical lake ecosystem

&lt;p&gt;Lake Ecosystem is a key component of biosphere that supports aquatic life and provide sink to the untreated effluent (domestic, industrial, and agricultural). Due to rapid industrialisation and changing climate, 30-40% of the lakes in the world are now eutrophic. The basic cause of eutrophication is the addition of nutrients (nitrogen and phosphate) into the lake system. Phosphate has been observed to be the limiting nutrient in 80% of the lakes and reservoirs in the world. Unlike other elements, phosphate does not escape from the system but changes from one form to the other depending upon the prevailing physico-chemical conditions. Chemical parameters like pH and redox potential are the major governing factors for phosphate fluxes. Sediments in the benthic zone serves as a sink as well as the source of phosphate for the photic zone. In the present study, a relationship between the physico-chemical properties of water and the fractions of phosphate in the sediments were studied. The study was conducted during three different seasons i.e. post-monsoon, winter, and summer to observe the seasonal variation. The pH, DO, ORP, and available phosphate in the water varied from 8.5, 14.7 mg/l, 39 mV, and 5.8 mg/l, 8.4, 3.5 mg/l, -64 mV, and 8.7 mg/l, and 7.8, 7.3 mg/l, 119 mV, and 10.5 mg/l during post-monsoon, winter, and summer, respectively. Phosphate in sediments was fractionated using SMT protocol. It was categorised under inorganic and organic phosphate classes, and the inorganic phosphate was further categorised as Non apatite inorganic phosphate (NAIP: Fe/Al bound) and Apatite inorganic phosphate (AIP: Ca bound). &amp;#160;The inorganic phosphate in the sediments was observed to be more than organic phosphate during post monsoon and summer, and at the same time the available phosphate in the overlying water was found low in concentration. The growth of phytoplankton is constrained by decreasing bio available phosphate in water. Concentration of NAIP was observed to vary with redox potential and concentration of AIP with pH. The study justified the hypothesis of direct relationship of sediment chemistry with bio availability of phosphate in water. Winter was found to be the extreme weather for phosphate fluxes. The findings point towards need of proper management such as chemical precipitation, sediment dredging etc. during this extreme weather conditions.&lt;/p&gt;

Engineered Root Bacteria Release Plant-Available Phosphate from Phytate

ABSTRACTMicroorganisms that release plant-available phosphate from natural soil phosphate stores may serve as biological alternatives to costly and environmentally damaging phosphate fertilizers. To explore this possibility, we engineered a collection of root bacteria to release plant-available orthophosphate from phytate, an abundant phosphate source in many soils. We identified 82 phylogenetically diverse phytase genes, refactored their sequences for optimal expression inProteobacteria, and then synthesized and engineered them into the genomes of three root-colonizing bacteria. Liquid culture assays revealed 41 engineered strains with high levels of phytate hydrolysis. Among these, we identified 12 strains across three bacterial hosts that confer a growth advantage on the model plantArabidopsis thalianawhen phytate is the sole phosphate source. These data demonstrate that DNA synthesis approaches can be used to generate plant-associated strains with novel phosphate-solubilizing capabilities.IMPORTANCEPhosphate fertilizers are essential for high-yield agriculture yet are costly and environmentally damaging. Microbes that release soluble phosphate from naturally occurring sources in the soil are appealing, as they may reduce the need for such fertilizers. In this study, we used synthetic biology approaches to create a collection of engineered root-associated microbes with the ability to release phosphate from phytate. We demonstrate that these strains improve plant growth under phosphorus-limited conditions. This represents a first step in the development of phosphate-mining bacteria for future use in crop systems.