Biochar enriched with fertilizers has the potential to improve the quality of acid soils. In the agricultural sector, it was reported that the sap of <em>Kappapychus</em><em> alvarezii</em> (K-sap) is often used as a biofertilizer. Therefore, this study aimed to (i) examine the character of biochar enriched with the K-sap and (ii) analyze the soil quality after incubation. This study was carried out using two treatment factors arranged in a randomized block design, namely the biochar dose at 0%, 2.5%, 5.0%, and 7.5% in weight and K-sap at concentrations of 0%, 5%, 10%, and 15%.  Ten kilograms of acid soil were incubated with K-sap enriched biochar for up to 2 weeks in each experimental pot. The results showed that the absorption band increased with the K-sap concentration for the functional group associated with the OH-stretching of the biochar enriched with K-sap was stronger and wider than the unenriched. The peak elevation pattern detected by X-ray diffraction for all biochars was similar. The dosage of 7.5% biochar enriched with 5%-10% K-sap concentrations increased pH, EC, organic C, total N, C:N ratio, available P, and exchangeable K, Ca, Mg, and Si than those without treatment. Furthermore, ammonium and total spores of arbuscular mycorrhizal fungi decreased, flagellates increased with and without the biochar, while the nitrate, total bacteria, and fungi of all treatments were similar. Based on these results, it was concluded that biochar enriched with K-sap could improve the quality of acid soil.

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The realization of sustainable agriculture requires continuous research which can reduce the use of chemical fertilizers. This research was carry out to obtain the potential indigenous endophytic bacteria isolated from onion planted on rock soil of Wakatobi district in Southeast Sulawesi. The study conducted using a completely randomized design (CRD) consisting of 9 isolates. Germination was recorded daily until 14 days. At the same time, isolates evaluated for their ability to solubilize phosphate, fix N and synthesize IAA. Results showed that the seed treatments using endophytic bacteria significantly increased viability onion seeds, in term of germination increases in germination percentage. Almost all endophytic bacteria isolate tested were able to solubilize phosphate, fix N and synthesize IAA. From this study, Ke03 isolates showed the best performance and were able to increase germination percentage, root length and number of onion roots reaching 145%, 46% and 78% respectively, as compared to controls. The ability of Ke03 isolates to increase onion germination correlated with the ability of this isolate to synthesize IAA (80.33 ppm). Further research is needed to evaluate whether this isolate is effective in increasing the growth and yield of onions in the field.

Abstract. Upland red rice (Oryza sativa) contains anthocyanin, a phenolic compounds that can act as antioxidants and functional food for human dietary. The content of functional food on upland red rice is influenced by shading condition, but the production is also influenced by environmental condition, especially the availability of light. The study aims is to assess and analyze the effect of shade on the growth and production of upland red rice. The research was conducted using the quantitative method to obtain the optimal shading condition that can increase the rice anthocyanin content and relatively high production. The research was arranged in split plot design, with shade as main plot and the different of cultivar as sub plot with three replications. The shading treatment consist of 4 levels as follows: n1=shade level < 25 %, n2=shade level 25-50%, n3=shade level 50-75% and n4=shade level > 75%. The cultivar tested were (v1) = Labandiri, (v2) = Jangkobembe, (v3) = Ranggohitam, and (v4) = Paedara. The rice planted in between teak wood trees with different age and level of canopy. The research reveals that shades had an effect in decreasing plant production (the higher level of shade, the higher the decrease level of production), but the shades can improve the quality of red rice through the increase of anthocyanin content.

Application of seed bio-invigoration treatment was able to break seed dormancy of local upland rice of cv. Pae Parigi 2 with the best treatment was using KNO3 1%+ground brick+Bacillus sp., CKD061.