Doses Of Compost Research Articles

“Alperujo” Compost Improves Nodulation and Symbiotic Nitrogen Fixation of Soybean Inoculated with Bradyrhizobium diazoefficiens

The utilization of compost to enhance plant productivity and symbiotic nitrogen fixation (SNF) has been recognized as an effective alternative to synthetic nitrogen fertilizers. This environmentally sustainable method is readily accessible to farmers. This study investigated the effect of olive pomace (“alperujo”, AL) compost on the nodulation and SNF of soybeans (Glycine max L.) and their natural symbiont (Bradyrhizobium diazoefficiens). For that, soybean plants were subjected to several doses of AL compost under controlled greenhouse conditions. At the end of the experiment, the dry weight of plant biomass (aerial part and roots), the number and fresh weight of nodules, and nitrogen and leghaemoglobin contents were analyzed. The application of AL compost significantly improved soybean growth, as demonstrated by an increase in both plant biomass and height. Furthermore, nodular leghaemoglobin content and nitrogen content were found to be enhanced by the addition of AL compost (7 and 40%, respectively), indicating an increase in nodule effectiveness and symbiotic efficiency. Our results provide clear evidence of the synergetic effect of AL compost on the soybean-B. diazoefficiens association, probably due to AL-compost improved soybean roots development, and rhizospheric organic matter and nutrients assimilation by rhizobia.

Survival Rate, Disease Incidence, and Yield of Shallots by Seed Priming and Application of Tithonia Compost Enriched with Gliocladium virens

This study aimed to evaluate the effects of seed priming with Moringa leaf extract (MLE) and the application of Tithonia compost enriched with Gliocladium virens on survival rate, disease incidence, and yield components of shallot. This research was carried out from September to December 2022 at the Teaching Farm, Faculty of Agriculture, Hasanuddin University. The study was conducted with a factorial design of two factors with three replications. The first factor was seed priming, consisting of unprimed hydropriming, 12.5% MLE, 25% MLE, and 37.5% MLE. The second factor is the dose of compost, composed of 0 t/ha, 5 t/ha, 10 t/ha, and 15 t/ha. All data were evaluated using analysis of variance (ANOVA) and Tukey’s multiple means comparison to determine statistical differences between treatments at the 95% confidence level. The results showed that seed priming with MLE and Tithonia compost enriched with Gliocladium virens affected the percentage of surviving seedlings after transplanting. Alone, seed priming with MLE at a concentration of 37.5% and application of Tithonia compost at a dose of 15 t/ha had the best effect on the number of bulbs per plant, bulb weight, bulb diameter and bulb production. Furthermore, adding Tithonia compost enriched with Gliocladium virens reduced the incidence of Fusarium wilt. As a result, the use of MLE as a priming agent and the addition of Tithonia compost enriched with Gliocladium virens is recommended.

Pengaruh Pupuk Organonitrofos dan Volume Irigasi Terhadap Pertumbuhan Mint (Mentha piperita L.) Organik

Mint (Mentha piperita L.) is one of the aromatic herbs. The aim of this research was to investigate the effect of organonitrophos (organic fertizer) and irrigation water volume on the growth and yield of organically cultivated mint. The experiment was conducted in a completely randomized design (CRD) with two factors, namely the dose of organonitrophos consisting of 4 levels: D0 (0%), D1 (10%), D2 (30%), and D3 (50%) of the total weight of the media, and irrigation volume consisting of I1 (20-40%), I2 (50-70%), and I3 (80-100%) of the field capacity. The results showed that the dose of organonitrophos fertilizer and irrigation water volume affected the growth and yield of mint. The treatment that statistically produced the highest oven-dried weight (18.67 grams per plant) was D3I2 (50% compost fertilizer and 50-70% irrigation water). The treatment that produced the highest fresh weight (104.7 grams per plant) and was the most efficient was D2I1 (30% compost dose and 20-40% irrigation water). However, as a consequence, the choice of D2I1 significantly reduced the weight of oven-dried yield to 13.33 grams per plant. Keywords: Organic, Mentha, Piperita, Organonitrofos, Irrigation

Pengaruh Aplikasi Kompos TKKS Pada Media dan Auksin Terhadap Pertumbuhan Bibit Kelapa Sawit (Elaeis guineensis Jacq) di Pre Nursery

Oil palm (Elaeis Guineensis Jacq) is a leading and main plantation commodity in Indonesia. Its main product consists of palm oil (CPO) which has high economic value. Applying compost is an effort to increase the production of oil palm plants. To support the growth of oil palm seedlings, growth regulators (ZPT) can also be given to plants in addition to fertilizing, because ZPT is an organic compound that functions to stimulate plant growth. This study aims to determine the effect of OPEFB compost application on media and auxin on the growth of oil palm seedlings (Elaeis Guineensis Jacq) in the Pre Nursery. This study used the Randomized Block Design (RBD) method. The factorial consists of 2 factors, namely: Factor I is the dose of OPEFB compost which is denoted (T) which consists of 4 levels, namely Without OPEFB compost (control) (T0), 40 gr/polybag (T1), 50 gr/polybag (T2), and 60 gr/ poly bag (T3). Factor II Auxin concentration symbolized (N) which consists of 4 levels, namely: Without Auxin (control) (A0), 1 cc Auxin /l Water (A1), 2 cc Auxin /l Water (A2), and 3 cc Auxin /l Water (A3). The results of this study indicated that the OPEFB compost treatment had a significant effect on seedling height, leaf length and leaf width. The higher the dose of OPEFB compost given up to 60 g/polybag, the higher the growth of oil palm seedlings. The auxin treatment significantly affected seedling height, leaf length, and leaf width. The higher the concentration of auxin given up to 3 cc/l of water, the higher the growth of the oil palm seeds.Keywords: Auxin, Oil Palm Seeds; EFB Compost

The dynamics of changes in soil temperature due to the application of rice straw mulch on lettuce (Lactuca sativa L.)

Climate change that occurs globally in agriculture causes fail crops production, causing losses for farmers. This loss can be minimized by using rice straw mulch to reduce soil temperature and protect the soil from direct solar radiation on lettuce land. This study will examine whether treatment with rice straw mulch can affect soil temperature in lettuce land. The research was conducted at Nudira Fresh Green House PT. Nudira Sumber Daya Indonesia, Warnasari Village, Pangalengan Subdistrict, Bandung District, West Java. This research was conducted from March 1, 2022 to August 31, 2022. The data of this study used a factorial 4 x 2 Randomized Block Design with 3 replications. Factor I was the thickness of rice straw mulch 0 t ha− 1 (R0), 4 t ha−1 or 0.48 kg plot−1 (R1), 6 t ha−1 or 0.72 kg plot−1 (R2), and 8 t ha−1 or 0.96 kg plot−1 (R3) and factor II was the dose of cow manure (F1) and compost (F2) each 20 t ha−1 or 2.4 kg plot−1. The results showed that the application of rice straw mulch with the organic fertilizer has not significant effect on soil temperature in lettuce land. However, the application of rice straw mulch at a dose of 8 t ha−1 slightly better results in decreasing soil surface temperature at a depth of 0 cm, although not significantly different.

The role of hydrilla (Hydrilla verticillata (L.f.) Royle) as soil protectant in improving soil physical, chemical, and biological properties

One of the aquatic weeds inhibiting agricultural production is hydrilla. The plants are simply removed not far from the bunds to prevent them from competing with cultivated plants. However, hydrilla can be used to improve the physical, chemical, and biological properties of the soil. As an indicator of production, chili plants were planted in the trial field in Purworejo Village, Ngantang Sub-district, Malang District from October 2020 to January 2021 to test the dose of hydrilla compost. The treatments tested consisted of hydrilla compost doses of 5 t.ha⁻¹ (P₁), 10 t.ha⁻¹ (P₂), 15 t.ha⁻¹ (P₃), and 20 t.ha⁻¹ (P₄), and NPK (16:16:16) inorganic fertilizer dose of 250 kg.ha⁻¹ (P₅) as control. The experiment was arranged in a randomized block design with three replications. Analysis of variance showed no significant difference (F<0.05) in the number of flower results. Meanwhile, there was a significant effect on the number of fruits, fruit weight, and percentage of flowers into fruits (F>0.05). Hydrilla compost contained 17.3% organic C element, while the inorganic fertilizer contained 4.27%. Hydrilla compost contained decomposing microorganisms, including Pseudomonas luorescent group, Trichoderma sp., Aspergillus sp. and Penicillium sp. The optimum dose of hydrilla compost for chili plants is 20 t.ha⁻¹.

Effectiveness of water hyacinth compost and N, P, K, S fertilizer on S-available, S uptake, protein content, and yield of shallot in Inceptisols from Jatinangor

. Water hyacinth ( Eichhornia crassipes ) is a source of organic matter that can be used as compost to improve the soil quality and productivity of shallots. Shallots are horticultural commodities that have various benefits. Inceptisol soils dominate Indonesia, with an area of 37.5% of Indonesia's land area but have low soil fertility. Soil fertility can be increased by optimal fertilization. This experiment aimed to determine the dose of water hyacinth compost and nitrogen (N), phosphor (P), potassium (K), sulfur (S) fertilizer which gave the best effect on increasing available S, S uptake, protein content, and yield of shallots. The experiment was conducted from July to October 2021 at the Experimental Garden of the Laboratory of Soil Chemistry and Plant Nutrition, Faculty of Agriculture, Universitas Padjadjaran, Jatinangor. The experiment used a Randomized Block Design, consisting of seven treatments repeated four times. The recommended fertilizer doses used are 200 kg Urea, 500 kg ZA, 300 kg SP-36, and 200 kg KCl. The compost used was water hyacinth compost at a 25 t/ha dose. The results of this experiment showed that the treatment of ¾ compost + ¾ doses of N, P, K, and S was the best in increasing available S (26.79 mg kg -1 ), S uptake (7.03 mg/plant), protein content (0.95%), colors and shallot yield (number of tubers, fresh weight, and dry weight) on Inceptisols from Jatinangor.

Potential of Indigofera tinctoria Natural Dyes Compost on Maize Vegetative Growth

Expanding sustainable agriculture approaches is critical to increase crop growth and productivity. This farming system should involve organic fertilization and not neglect the recycle of organic waste. One of the organic wastes that can be used as compost is Indigofera tinctoria natural dye waste. The research objective was to examine the vegetative growth response of corn plants to Indigofera tinctoria compost. The design used was a complete randomized block design with one factor of fertilization doses with 3 six levels namely 2.91; 5.83; 8.75; 11.67; 14.58 tons/ha, and chemical fertilizers as controls. Indigofera tinctoria compost meets the standards as organic fertilizer according to the Ministry of Agriculture with characteristics of 18.2% water content, 52.48% organic C, 90.48% organic matter, 2.84% total nitrogen, 1.54% total phosphate, total potassium 2.44%, 1.30% available nitrogen, 0.92% available phosphate, 1.52% available potassium and 60 cmol/kg cation exchange capacity. The dose of compost significantly affected on plant height of 2-4 WAP, stem diameter of 2 WAP , and root biomass of 2 WAP. The compost dose of 5.83 tons/ha has increased root growth and plant height.

Perbaikan kualitas tanah berpasir untuk kebun kopi dengan penambahan tanah liat dan kompos di Desa Bambang, Kecamatan Wajak

Introduction: This study focuses on the effect of applying clay and compost on improving the quality of sandy soil in terms of the physical and chemical quality of the soil so that it can be a solution to problems in managing sandy soil so that the land can be productive and sustainable. Methods: This study used a factorial completely randomized design (RAL-F) with 3 treatment factors, namely: Depth (K1: 0-30 cm, K2: 30-60 cm), Dosage of compost (M1: 0 ton ha-1 as control, M2: 20 ton ha-1), Percentage of mineral soil (T1: 0% as control, T2: 25%, T3: 50%). Each treatment was repeated 4 times to obtain 48 pot units for the experiment. Data collection is carried out every 2 weeks for soil pH data. As for the other observation parameters taken in the last week of the incubation process, the data taken are chemical data in accordance with predetermined observation parameters which include soil physical properties such as bulk density, specific gravity, porosity, moisture content, pF value and basic chemical properties such as pH, organic matter, P-Available, N-Total. Results: Based on the results of laboratory analysis, it was shown that there was an increase in the average value of pH H2O and pH KCl every week, where initially the pH of H2O was 5.3 (1 MSI) to 5.9 (11 MSI) and the pH of KCl was from 5.1 (1 MSI) to 5.5 (11 MSI). This proves that the addition of organic matter and clay to the soil can increase the soil pH value. In addition to an increase in soil pH, there was also an increase in other chemical properties (BO, total-N and available-P) as well as soil physical properties (BI, BJ, Porosity and pF 2.5). Conclusion: the addition of clay soil and compost can improve the quality of sandy soil, especially the soil chemistry characteristics.

Aplikasi Kompos Tandan Kosong Kelapa Sawit (TKKS) terhadap Pertumbuhan dan Hasil Tanaman Melon (Cucumis melo. L)

One of the fruits favored by the community is melon (Cucumis melo. L), which is classified as a horticultural commodity. Melon has prospects for cultivation because it contains many vitamins and benefits. This research was carried out in August - December 2019 in Limau Manis Village, Pauh District, Padang City. The research method is an experimental method using a completely randomized design (CRD) with 4 treatment levels and 5 replications. The level of treatment given was the dose of OPEFB compost 10, 20, 30, 40 tons/ha. Observational data were analyzed statistically with the F test at the 5% level. The results of the analysis of variance were continued with Duncan's New Multiple Range Test (DNMRT) at the 5% level. The results showed that the application of oil palm empty fruit bunches compost at a dose of 30 tons/ha had the best effect on the growth of height and stem diameter of melon plants. However, the application of oil palm empty fruit bunches compost at doses of 10, 20, 30, and 40 tons/ha has not been able to have a significant effect on melon crop production.

The Integrated Minapadi (Rice-Fish) Farming System: Compost and Local Liquid Organic Fertilizer Based on Multiple Evaluation Criteria

Rice-fish cultivation, also known as Manipadi in Indonesia, is one of the many integrated farming systems where fish are grown concurrently with rice. However, this integrated system needs to be optimized by organic fertilizer. The application of organic fertilizers, such as compost and local biofertilizers, when implemented into this integrated system, can optimize the yield per land for both rice and fish. However, this combination must be evaluated systematically by multiple evaluation criteria and statistical analyses. Therefore, this study aimed to identify the combination of compost doses and/or local liquid organic fertilizer concentrations, based on multiple evaluation criteria, that supports the productivity of rice-fish integration agriculture. The experiment was carried out in the Wanuae farmer group of the Barebbo District, Bone Regency, Indonesia, between September 2018 and January 2019. The experiment employed a split plot design with a randomized complete block design (RCBD). The main plot consisted of compost (four levels), and the subplot was the local biofertilizer source (four levels). The results demonstrated that the number of fill grains was significantly affected by the compost treatment and the type of local biofiller. The effect of the compost dosing was more dominant in comparison with the local liquid organic fertilizer character and its interactions. A compost dosage of four tons ha−1 and a local liquid organic fertilizer, sourced from soaked coconut fiber with cow urine, has been recommended as the combination treatment to optimize the rice and fish yield potential. The Minapadi (rice fish) with additional high composting effectively increased the farmer’s outcome with a 2-point R/C ratio, more so than those without composting. Moreover, the compost dosage in this Minapadi study requires further exploration for a better understanding.

Evolution of Maize Compost in a Mediterranean Agricultural Soil: Implications for Carbon Sequestration

Compost amendments, apart from improving fertility and the general characteristics of agricultural soils, have known implications for global C cycling and sequestration in soils. Their effects are usually assessed via the quantification of soil organic carbon (SOC) pools, usually labile (fast) and recalcitrant (slow) pools, with varying intrinsic decomposition rates and distinct resident times. However, the real C-sequestration potential of organic additions to soil is still under discussion. In this study, a field trial and a lab incubation experiment were designed to study the C-sequestration mechanism in an agricultural Mediterranean soil. Soil with a history of C3 photosystem crop was amended with two maize composts from maize harvesting surpluses (C4 photosystem) with different maturity stages (AC: aged compost; NC: new, less mature compost). The evolution of SOM was monitored for 6 months using complementary analytical techniques, including analysis of stable C isotopes (IRMS), thermogravimetry (TG) and C-stock and priming effect (PE) modelling. Based on the natural C-isotope labelling, the proportion of new C was calculated. More than 50% of the C added to the soil with the compost was incorporated into the SOM in only 6 months. However, the application of maize compost did not always enhance soil C-sequestration capacity. The addition of compost caused a general PE, enhancing SOM decay and reducing the fast (labile) SOM mean residence time (MRT) (11.2 days). This was more pronounced with the addition of a higher dose of AC, causing a PE up to a 718%. On the other hand, a higher MRT (54.4 days) occurred in soils with NC applied, likely due to its deleterious effects, limiting heterotrophic activity. Despite that, the average MRT of the slow (recalcitrant) SOM pool was lower than usually reported. The application of higher doses of both composts generally showed greater MRT values compared to control (1.7 years vs. 3.8 and 2.9 years for NC and AC, respectively), leading to an increase in this more stable C pool and effective soil C sequestration. The results described in this work may help readers to better understand SOM dynamics and may be of use in designing appropriate management strategies for improving OM quantity and quality and to optimize C storage in Mediterranean soils.

Evaluación de abono orgánico en la producción de maíz en Villaflores, Chiapas, México

The use of organic fertilizers contributes to the improvement of the fertility of agricultural soils. The objective was to evaluate three doses of organic fertilizer incorporated into the soil (10, 20 and 30 t.ha-1) and a control, in corn production. The management of the crop was conventional, after the preparation of the soil with agricultural machinery, the doses of compost were incorporated. Planting was manual with a density of 66,500 plants.ha-1. A completely randomized design and three replicates per treatment were used. Data were analyzed with analysis of variance, tests of means, correlation analysis, and economic evaluation. The results indicated that the incorporation of organic fertilizer to the soil benefited the height of the plant and ear, leaf area, stem diameter, number and yield of ears.ha-1. A direct and positive relationship was found between the dose of amendment incorporated into the soil and the production of ears in the milky-dough state. The application of 30 t.ha-1 of organic fertilizer showed the best results for the indicated agronomic variables and presented the best economic benefits.

Measures for Controlling Gaseous Emissions during Composting: A Review.

Composting is a promising technology for treating organic solid waste. However, greenhouse gases (methane and nitrous oxide) and odor emissions (ammonia, hydrogen sulfide, etc.) during composting are practically unavoidable, leading to severe environmental problems and poor final compost products. The optimization of composting conditions and the application of additives have been considered to mitigate these problems, but a comprehensive analysis of the influence of these methods on gaseous emissions during composting is lacking. Thus, this review summarizes the influence of composting conditions and different additives on gaseous emissions, and the cost of each measure is approximately evaluated. Aerobic conditions can be achieved by appropriate process conditions, so the contents of CH4 and N2O can subsequently be effectively reduced. Physical additives are effective regulators to control anaerobic gaseous emissions, having a large specific surface area and great adsorption performance. Chemical additives significantly reduce gaseous emissions, but their side effects on compost application must be eliminated. The auxiliary effect of microbial agents is not absolute, but is closely related to the dosage and environmental conditions of compost. Compound additives can reduce gaseous emissions more efficiently than single additives. However, further study is required to assess the economic viability of additives to promote their large-scale utilization during composting.

Efek Pemberian Kompos dan Biochar terhadap Pertumbuhan Bawang Merah (Allium ascalonicum L.) True Shallot Seed Pada Typic Hapludults

The research was aimed to determine the growth of shallot (Allium ascalonicum L.) from true shallot seed (TSS) by giving compost and biochar in Typic Hapludults soil. This research was conducted at the Greenhouse and Laboratory of Soil and Agroclimate, Agriculture Faculty, Sultan Ageng Tirtayasa University and conducted on November 2020 to January 2021. This research used a factorial randomized block design (RBD) consisted of two factors, that were compost and biochar dosage that mixed into the suboptimal soil. The first factor was the dosage of compost (K) which consisted of 3 levels, that were 12.5 tonnes/ha (k1), 25 tonnes/ha (k2), and 37.5 tonnes/ha (k3). The second factor was the dosage of biochar (B) which consisted of 3 levels of experiment, namely 7.5 tonnes/ha (b1), 10 tonnes/ha (b2), and 12.5 tonnes/ha (b3). The results showed there was no interaction between the application of compost and biochar to suboptimal soil on the growth and yield of shallot. Giving biochar of 7.5 tonnes/ha had a significant effect on the parameters of the number of leaves at 1 WAP.

Dose-dependent impact of compost on rhizosphere bacterial community in heavy metal-contaminated paddy soil

Different doses (1%, 5%, 10%, mass fraction) of animal manure compost were added into a multi-heavy metal contaminated paddy soil for 150 d, and the changes in microbial structure and composition were evaluated. Compost exhibited dose-dependent effects on the rhizosphere bacterial community. Low (1%) and middle (5%) additions of compost exerted more distinct influence on bacterial community structure in rhizosphere soil than in bulk soil. The bacterial diversity after addition of compost decreased in rhizosphere soils compared with that in bulk soil. Results of redundancy analysis (RDA) indicated that different responses of rhizosphere and non-rhizosphere bacterial community to the changed soil physicochemical properties (soil pH, Pb, Cd and Cu levels) might be one reason for the differences. Thus, in agricultural management practice, the influence of compost on rhizosphere microbes should be considered.

Organo-Mineral Fertilization Based on Olive Waste Sludge Compost and Various Phosphate Sources Improves Phosphorus Agronomic Efficiency, Zea mays Agro-Physiological Traits, and Water Availability

In the context of intensive and sustainable agriculture, limiting soil degradation and the loss of organic matter has become an obligation to maintain food security. The use of organo-mineral fertilizer (OMF) products is an innovative technology that may solve the different challenges raised. This study aimed to evaluate the effect of various organo-mineral fertilizer (OMF) formulations on Zea mays agro-physiological traits, phosphorus (P)-related parameters, and water conservation during a 90-day pot experiment. The OMF formulations consisted of blending several doses of a stable OMWS compost (10 t /ha(OMF1), 50 t/ha (OMF2), or 100 t/ha (OMF3)) with different sources of mineral P, namely diammonium phosphate (DAP), rock phosphate (RP), or phosphate washing sludge (PWS), compared with separate applications. The results indicated that the effect of an OMF on the soil and plants was strongly dependent on the source of P used and the dose of OMWS compost. The best agronomic performance was attributed to OMF1-based DAP, which resulted in a significant improvement in the shoot and root biomass dry weight by more than 260% and 40%, respectively. However, using an OMF2 formulation was more optimal when using RP and PWS as mineral P sources. Independently of the type of P fertilizer, the addition of stable OM systematically improved multiple soil properties, including water availability, and the nutrient concentrations, such as the available P, exchangeable potassium, and magnesium. Furthermore, the plant’s respiration, photosynthetic activity, and nutrient assimilations were positively affected by the OMF formulations. Overall, our results demonstrate that organo-mineral fertilization is a promising solution for increasing the efficiency of low-P and high-P mineral fertilizers in alkaline soils through direct and indirect mechanisms involving improved soil properties and higher P solubilization.

The effectiveness of the use of organic fertilizers in the link of crop rotation on light gray forest soil of the south of the Volga-Vyatka region

Relevance. The issues of reproduction of fertility of light gray forest soils of the forest-steppe zone and utilization of poultry industry waste as organic fertilizers are interrelated and are very relevant. Methods. The experiments studied the effect of one-time application of various doses (15, 30, 50 t/ha) of chicken manure, chicken manure compost and local organic fertilizers (sapropel and peat) on crop yields, and the aftereffect of fertilizers on the main indicators of soil fertility — amount of humus, nitrate nitrogen, phosphorus and potassium. The variants of the experiments were investigated sixfold. The Federal State Center of Agrochemical Service "Chuvashsky" was involved in laboratory analyses of soils and crop production. Mеthods of analysis of soil samples and crop production are generally accepted in agrochemical science.Results. Organic fertilizers for three years of research were introduced into the soil only once at the beginning of the experiment in doses of 15, 30 and 50 t/ha, and their effect on the yield and quality of crop production (potato tubers, spring wheat grains and peas) in 2020–2022 was positive. The agrochemical properties of the arable soil layer in the variants with the use of organic fertilizers have significantly improved. The nitrate content in the products in variants with doses of chicken manure and compost of 50 t/ha or more approached the critical level. Local fertilizers (sapropel and peat) at a dose of 30 t/ha, chicken manure and compost at a dose of 15 t/ha are good organic fertilizers with a long aftereffect.

Utilizing Compost Soil Conditioner in Beach Sand Soil as a Palm Oil (Elaeis guineensis Jacq) in Pre-nursery Media

The objective of this study was to assess the effect of the type and dose of compost on the growth of oil palm seedlings in pre nursery with coastal sandy soil. The other objective is to know the effect of the type of compost on the growth of oil palm seedlings in pre nursery with coastal sandy soil. Lastly, the study examines the right dose of compost that provides the best growth of oil palm seedlings in pre nursery with coastal sandy soil. The experimental design was set in a factorial completely randomized design (CRD) consisting of two factors from April to June 2020 at the Tridharma Research Station Faculty of Agriculture, INSTIPER. The first factor is the type of compost which consists of 2 levels, Lamtoro compost, and vermicompost. The second factor is the dose of compost consisting of 4 levels: control (without compost), 50 gr compost/polybag, 75 gr compost/polybag, and 100 gr compost/polybag. The research data were analyzed using analysis of variance (α =0,05), and if there was a significant effect, it was continued with the Duncan multiple range test ( α = 0,05). Parameters observed included seedling height, total leaf, leaf width, stem diameter, shoot dry weight, root dry weight, root length, and total roots. The results showed that no combination of types and doses of compost significantly affected the growth of oil palm seedlings in pre-nursery. Using vermicompost can significantly increase oil palm seedlings' leaf area and root dry weight. Using compost at a dose of 50 g/polybag increased seedling height, stem diameter, and root dry weight in pre-nursery of oil palm seedlings.

Soybean growth and yield on corn cob compost application

The continuous use of chemical fertilizers contributes to gas emissions that cause global warming, climate change and low nutrient use efficiency. Compost is an effort to increase nutrient supply to improve soil quality and nutrient efficiency in food crops. The aim of the study was to examine the role of corn cob compost on soybean growth and yield. The study used a complete randomized block design with one factor, namely the dose of corn cob compost with six levels, namely chemical fertilizer 0.225 ton/ha, corn cob compost dose 2; 3; 4;5; 6 tonnes/ha. The dose of compost affects the root biomass. Corn cob compost 5 tons/ha was able to increase soybean yields by 2.28 tons and was not significantly different from chemical fertilizers. Corn cob compost 5 tons/ha produced the highest weight of 100 seeds, namely 41.33 g. Soybean yields were positively correlated with root biomass, number of leaves and crown biomass. Compost from corn cobs is an organic nutrient that can promote soybean growth and yield.