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Upland rice farming plays a crucial role in ensuring food security in Indonesia. This study aimed to evaluate the impact of plant growth-promoting rhizobacteria (PGPR) isolates on the growth of upland rice. The bioassay and pot experiments were conducted to select the capable isolates of PGPR and to investigate the effect of the PGPR inoculant on the N fertilizer efficiency and agronomic traits of upland rice. The bacterial isolates were identified through a biochemical analysis and tested under controlled greenhouse conditions. The selected PGPR inoculant was formulated as a liquid biofertilizer (LB). The three capable isolates were obtained to fix nitrogen, produce indole-3-acetic acid (IAA), organic acid, and nitrogenase activity and were identified through a biomolecular analysis as Delftia tsuruhatensis strain D9, Delftia sp. strain MS2As2, and Bacillus sp. The application of the LB into the soil at a dose of 10 L ha−1 and 50 kg ha−1 N resulted in a grain yield of 29.81 g pot−1 and a relative agronomic effectiveness (RAE) value of 235.08%, signifying a significant improvement over the conventional method. Several variables, including the number of grains, number of panicles, root length, 1000-grain weight, population of nitrogen-fixing bacteria, and nitrogen uptake exhibited a strong correlation with the grain yield, accounting for 97.80% of the observed variation. These findings show the enormous potential of PGPR isolates, specifically of Delftia tsuruhatensis strain D9, Delftia sp. strain MS2As2, and Bacillus sp., in significantly enhancing the upland rice output in Indonesia. Furthermore, the use of an LB as a biofertilizer in conjunction with nitrogen fertilization provides a viable and sustainable way to increase yields and enhance the overall sustainability of the region's upland rice farming systems. [ABSTRACT FROM AUTHOR]

This research was conducted to determine plant biomass, carbon potential, and CO2 reserve potential in understory vegetation in general, namely grasslands, shrubs, and rainfed rice fields. The sampling of the research was carried out randomly and intentionally, and was limited to the vegetation of reeds, shrubs and rainfed land bushes in the Aceh Besar District of Indonesia. The sample was taken based on a digitized map obtained from overlaying the land use map, slope map, soil type map, and Aceh Besar government map. Measurement of biomass in the vegetation of Imperata, shrubs, and rainfed rice fields is in accordance with procedures from the Indonesian National Standard (2011) and the World Agroforestry Center. The area of bush vegetation is larger than that of rainfed rice fields and grasslands. In general, the plants found in bush vegetation are Acacia leucoeplhoea, Mimosa pudica, Cyperus rotundus, and Eleusine indica. Grassland vegetation has one plant only, namely, Pennisetum purpureum. The vegetation of rainfed rice fields consists of the Oryza sativa type of plant. Plant biomass, carbon [C] content, and carbon potential in bush vegetation are greater than that of grassland and rainfed rice fields, as well as plant biomass reserves, plant biomass carbon and total CO2 reserves. Shrubs and woody plants render the potential for biomass, carbon, and CO2 absorption greater than that of grassland and rainfed rice fields. This is in accordance with the research that the increase in biomass is followed by an increase in potential carbon storage. Parameters that affect biomass indirectly will also affect carbon storage in a biomass and in an ecosystem, namely, individual density, stem diameter, tree species diversity, and soil. The density of trees in an area will affect the increase in carbon stocks through an increase in biomass. This is because the vegetation of shrubs does not only consist of undergrowth, but also of woody stems such as Acacialeucoeploea, making carbon stock potential in bush vegetation greater than that of grassland and rainfed rice fields, as shrubs cover an area of 96,962.2 ha, hence larger than that of grasslands and rainfed rice fields. [ABSTRACT FROM AUTHOR]

Background: Brown spot disease is one of the most destructive foliar diseases of rice. Biological control of this disease is considered more environmentally safe, but the biological control agents have limited availability. The fungus Trichoderma can be used as a biocontrol agent for various plant diseases, including brown spots. Indigenous Trichoderma species from West Timor were evaluated in this study to reveal their effectiveness in reducing brown spot disease of upland rice. The study was conducted under a screen house condition using a factorial treatment design laid out in a completely randomized design. The two factors were the brown spot disease control method (T. viride, T. harzianum, T. hamatum, fungicide Trivia 73 WP, and a control treatment) and upland rice genotype (Inpago 7 and Breun Senaren 2). Results: The results showed that Trichoderma spp. and the fungicide Trivia 73 WP caused significantly lower AUDPC and apparent infection rate than the control treatment. The total phenol content and agronomic characters (number of reproductive tillers per plant, number of filled grains per panicle, grain yield per plant) were higher in the Trichoderma and fungicide treatments than the control treatment. Meanwhile, tannin and saponin levels were non-significantly different among treatments. Trichoderma and the fungicide Trivia treatments effectively suppressed brown spot disease of upland rice, and the efficacy was dependent on the rice variety, with a mean efficacy range over the two varieties of 27.05–36.42%. The Trichoderma and the fungicide Trivia treatments increased the grain yield per plant differentially in the 2 rice varieties, with a mean grain yield increase over the 2 varieties of 13.0% (T. viride), 23.5% (T. harzianum), 35.0% (T. hamatum), and 19.9% (Trivia 73 WP). Conclusion: Efficacy of local Trichoderma of West Timor and the fungicide Trivia treatments were varietal dependent with T. hamatum being the most effective in reducing the brown spot disease and producing the highest grain yield increase over the 2 rice varieties. The local Trichoderma species of West Timor have a future potential as biocontrol agents of upland rice brown spot disease, but it is necessary to further evaluate their effectiveness against the disease in replicated field trials. [ABSTRACT FROM AUTHOR]

Background: The main problem in nitrogen fertilization for crop cultivated is the very low efficiency due to the leaching process. The purpose of this study was to the determination of the optimum levels of biochar amendment made from Melaleuca cajuputi biochar (MCB) and urea fertilizer (UF) for nitrogen use efficiency in upland rice under M. cajuputi stands. Methods: The study was conducted during dry season within March to June 2019 in Menggoran Forest Resort, Playen Forest Section, Yogyakarta Forest Management District, Indonesia. The experimental design was laid out in a randomized complete block design factorial with three replications as the response surface methodology (RSM). The treatments consisted of MCB levels (0, 5, 10, 15 tons ha-1) and UF levels (0, 100, 200, 300 kg ha-1) as independent variables. The observation parameters were nitrate reductase activity (NRA), total chlorophyll (TC), leaf photosynthesis rate (LPR), nitrogen loss (NL), nitrogen use efficiency (NUE) and seed yield (SY). The data was analyzed using RSM approach and ridge regression. Result: The optimizing applications of 11.14 tons ha-1 of MCB and 281.13 kg ha-1 of UF resulted in NUE and SY by 2.14 kg grain kg Nfertilizer-1 and 5.83 tons ha-1 or increased by 19.07% and 13.02%, compared to a single application of UF by 300 kg ha-1. [ABSTRACT FROM AUTHOR]

Abstract: Blast has become a major problem in the upland rice of Indonesia, as the improved resistant varieties with high yield performances released in the 90''s became susceptible only a few years after their release. The present study investigated the efficiency of association of susceptible and resistant varieties in reducing leaf and neck blast and increasing yield. Two sets of experiments were conducted in fields with associations through using different proportions of resistant variety, and two types of susceptible variety (moderately and very susceptible) in the association. The efficiency of the association was measured by comparing disease intensity and yield in the variety when grown in association and when grown as a pure stand. ANOVAs and logistic regressions indicated that resistant-susceptible variety association was more efficient in reducing neck blast than leaf blast. Associations were more efficient (1) when the proportion of resistant variety was increased, (2) when a moderately susceptible variety was used instead of a very susceptible variety, and (3) when disease level in the pure stand was higher. Associations did not penalize the performances of the resistant variety, neither in terms of disease intensity, nor yield. Logistic regressions allowed to estimate the probability of a given association to reduce disease (or to increase yield) above a preset threshold, according to the proportion of resistant variety and to the type of susceptible variety. [Copyright &y& Elsevier]

<b>Background and Objective:</b> The rate of population growth is not balanced with the rate of increase in national rice production. The attention of the government and researchers in Southeast Sulawesi on upland rice is still very low, even though the potential for increased upland rice production is quite promising. The research aimed to study the influence of KCl fertilizer and <i>Trichoderma </i>spp. on the growth and yield of upland rice. <b>Materials and Methods:</b> The study was conducted in a Randomized Block Design (RBD) consisting of 6 treatments i.e.: without KCl fertilizer and <i>T. asperellum</i> (K<sub>0</sub>), KCl 0.15 g/polybag+<i>T. asperellum </i>50 g/polybag (K<sub>1</sub>), KCl 0.30 g/polybag+<i> T. asperellum </i>40 g/polybag (K<sub>2</sub>), KCl 0.45 g/polybag+<i>T. asperellum </i>30 g/polybag (K<sub>3</sub>), KCl 0.60 g/polybag+<i>T. asperellum </i>20 g/polybag (K<sub>4</sub>) and KCl 0.75 g/polybag+<i>T. asperellum </i>10 g/polybag (K<sub>5</sub>) with 4 replication for each treatment. The data obtained were analyzed by analysis of variance (ANOVA) and conducted further tests with the Duncan Multiple Range Test (DMRT) at a 95% confidence level. <b>Results:</b> The results of the research revealed KCl fertilizer combination with <i>T. asperellum</i> in general, can increase the growth and yield of upland local aromatic red rice. Application of KCl fertilizers as 0.45 g/polybag equivalent to 90 kg ha<sup>1</sup> (K<sub>3</sub>) can provide optimal potassium nutrients for vegetative growth of upland rice. <b>Conclusion:</b> The treatment of KCl fertilizer as 0.45 g/polybag with <i>T. asperellum </i>30 g/polybag (K<sub>3</sub>) provides growth and yield of upland rice with an average production of4.95 t ha<sup>1</sup>.