Doses Of Organic Compost Research Articles

Impact of Organic Vegetable System on Soil Organic Matter Pools and CO2 Emission in the Tropical Region

ABSTRACT It is widely recognized that the input of organic matter in tropical agriculture is essential to maintain productivity and soil quality. This study aimed to investigate the dynamics of organic C pools and CO2 emission influenced by organic compost fertilization and leucaena biomass in an area of 6 years under organic farming. The system consisted of 5 treatments based on 5 levels of fertilization with organic compost (0, 10, 20, 30, and 40 t ha−1). Each block was surrounded by leucaena and their pruning’s were distributed in equal proportions for all treatments. Two rotating crops were performed per year, cabbage/corn. Soil samples were collected in the 0–10 and 10–20 cm layers in 2-year seasons. TOC and N stocks were between 23.1 and 51.6 t ha−1, and 2.1 and 5.4 t ha−1, respectively. The highest compost doses increased the microbial biomass C and N. The increase in microbial biomass was followed by higher emissions of C-CO2. Increased microbial quotient values indicated C accumulation in the system by a higher amount of active metabolic C. The microbial biomass was less efficient in the use of the high organic compost doses. The dose of compost should be reduced and applied constantly by the farmers to attend the plant demand by nutrients and increase the efficiency of C sequestration in the soil. This C sequestration will also improve biological activity and soil quality in tropical regions, increasing food production.

POPULAÇÃO DE NEMATOIDES EM CAFEEIRO ADUBADO COM COMPOSTO ORGÂNICO

INTRODUCTION: The use of organic compost to increase organic matter has been a great ally of the rural producer, since it is a practice of easy access, financially viable and ecologically sustainable. Thus, understanding the influence of organic composts on the incidence of nematodes in the soil, consequently, can help reduce the damage caused by these organisms. OBJECTIVE: Influence of organic compost fertilization on nematode population in soil cultivated with coffee trees. METHODS: A randomized block design was used in the experiment, with five treatments (doses of organic compost, 0, 2.5, 5, 7.5 and 10 t ha-1), divided into four blocks, totaling twenty experimental units. The soils had already been corrected with limestone application at doses of 0, 1, 2, 3, and 4 t ha-1. The dose of organic compost application was inversely proportional to the dose of lime application. RESULTS: The results showed a significant increase in calcium, potassium, base saturation and base sum levels. CONCLUSION: The organic matter content does not interfere in the nematode population.

Basalt rock powder and organic compounds in corn crops

The use of basalt rock powder associated with an organic fertilizer with compost can be an option to reduce the use of soluble fertilizers. Thus, this study aimed to evaluate the effect of organic compost and basalt rock powder on the agronomic traits of the corn crop and on the levels of nutrients available in the soil solution, with two additional treatments of fertilization with NPK. The experimental design used was completely randomized blocks, in a factorial scheme (5x2) + 2, with two additional and four replications. The first factor consisted of five doses of organic compost (0, 4, 6, 8 and 10 t ha-1) and the second factor, with and without basalt rock dust (0 and 8 t ha-1). The additional treatment consisted of the application of 150 kg ha-1 of formulated NPK (10-15-15), equivalent to ½ of the recommended dose for the crop, associated with 8 t ha-1 of basalt rock powder and the second additional treatment consisted in the application of 300 kg ha-1 of formulated 10-15-15 of NPK and without rock dust. The agronomic characteristics of corn and the nutrient contents in the soil solution were evaluated. The results showed that the use of organic compost associated with rock dust promoted soil chemical improvements, especially pH elevation and calcium content increase. There was no effect of organic compost with rock powder on the agronomic characteristics of corn evaluated. The use of chemical fertilizer of an NPK formulation improved the corn crop compared to the use of organic compost and rock dust. The application of 8 t ha-1 of basalt rock powder, associated with 150 kg ha-1 of a formulated NPK improved the development of the corn crop compared to the use of 300 kg ha-1.

Incidence of potato green aphid and Lyriomiza sp. in radish plants grown on different levels of organic fertilizer

Radish is a short cycle horticultural product from family Brassicaceae. Between the insects found on radish leaves, potato green aphid (Myzus persicae Sulzer) is one of the main pests of this culture, causing economic damage. Synthetic fertilizers used in conventional crops can promote changes in the pattern of amino acids in plants, leading to a higher insect damage. The source of fertilization is one of the factors that could influence in the incidence of pests. The objective of the study was to evaluate the incidence of potato green aphid and other pests on radish plants grown with different doses of organic fertilizer. The experiment was carried under semi-field conditions, in Fortaleza (Ceará State). A completely randomized design was used, with six replicates. The treatments consisted of five doses of organic compost (0; 45; 60; 75; 90 t.ha-1). For the population survey of pests and natural enemies, counts were made in three evaluations (7, 14 and 21 days after sowing). The counting data were subjected to deviance analysis using a generalized linear model (GLM). It was observed significant differences in the number of adults M. persicae in the treatments of 75 and 90 t.ha-1. Presence of leafminer (Lyriomiza sp.) was observed on plants without and with the lower doses of organic fertilizer. Even using organic fertilizers that promote a slower liberation of nutrients, high incidence of pests (Mainly M. persicae) was observed on radish plants.

The effect of organic compost of Caryocar brasiliense waste against Meloidogyne javanica in two vegetable crops

Summary Root-knot nematodes (Meloidogyne spp.) are responsible for various significant crop losses, which require taking integrated control measures. The present study aimed to identify a possible sustainable approach to the management of Meloidogyne javanica in vegetable crops using an organic compound based on pequi (Caryocar brasiliense) fruit residues. A pot experiment was conducted using cultivars of tomato and lettuce susceptible to M. javanica, with three amendments including inorganic fertiliser, cattle manure and five doses of organic compost with pequi residues. All treatments were inoculated with second-stage juveniles of M. javanica to simulate the root-knot nematode disease in field conditions. Increasing doses of organic compost with pequi residues from 5 kg m−3 to 30 kg m−3 promoted a significant decrease in the nematode population in both cultures evaluated. Organic compost (30 kg m−3) reduced the numbers of galls and eggs of M. javanica by 41.6 and 46.5% in tomato roots, and by 80.3 and 59.2% in lettuce roots, respectively, compared with non-treated control. Organic compost also increased crop development considerably. In general, there was a 43.0% increase in plant development compared to non-treated control. Hence, organic compost of pequi residues could be an alternative to toxic chemical nematicides and recommended as eco-friendly management of M. javanica in vegetable crops.

Successive crops of lettuce fertilized with organic compost produced from cellulose paper residues

New technologies must ensure that the natural resources used can somehow return to the environment in an advantageous way. The objective of this study was to evaluate organic compost produced from cattle manure and cellulose paper residues and lettuce production. In the organic compost the Pb and Cd concentrations were below the limits of quantification by the methodology used. The organic compost was evaluated in two consecutive lettuce crops. The first cultivation was carried out in a completely randomized design in the 4x3+1 scheme with four replicates: four doses of organic compost, three different organic compost and additional treatment, without addition of organic compost. The second cultivation was carried out 90 days after the first one, without additional of fertilizers. In the soil, there was an increase in pH, CEC, SOC, P, K, Ca and Mg, after 2 consecutive crops. Significative concentrations of Ni, Cr, Pb and Cd not were found in the plants in both crops. The use of organic compost from cellulose paper residues in agricultural improved soil fertility and lettuce production, being the highest yields obtained in the second crop.

Organic Compost of Swine Manure in the Production of Green Corn in Manaus, Brazil

Pig farming is considered one of the activities with the greatest environmental impact due to the erroneous disposal of swine waste. The present work aimed to produce an organic compost using waste from pig production and evaluate its chemical characteristic, corn yield under doses of this organic compost and soil nutritional quality before and after the experiment implementation. The Corn was fertilized at sowing and 30 days after plant germination using organic compost from pig waste at the doses: 0, 2, 3, 4 and 5 t ha-1. The Corn used was CATIVERDE 02 and were seeded at 1.0 m spacing between rows and 0.40 m between plants, in a total area of 240 m2. The experimental design was randomized blocks with four replications and five doses of organic compost. The parameters evaluated for corn were: plant height, stem diameter, weight and corncob length. Fertilization with swine organic compost increases in soil P, K, Ca, even after the corn harvest. The best treatment was with a dose of 5 t ha-1, as it resulted in higher plant height (1.85 m) and corn cob weight (261 g).

Organic compost as a conditioner of soils cultivated with yellow passion fruit

This research aimed to evaluate the effect of doses of organic compost on the yield and economic profitability of organic yellow passion fruit grown in sandy-loam and clay-loam soils. Two experiments were installed in the field, in different soil types and municipalities in the state of Acre. The experimental design was in randomized blocks with five treatments, four replications, and four plants per experimental unit. The treatments consisted of adding the compost as a replacement for 1/3 of the volume of cylindrical planting holes with 40 cm, 80 cm, 120 cm, 160 cm, and 200 cm, corresponding to the addition of 6.3; 25.1; 56.5; 100.4, and 156.9 liters per planting hole, respectively. The mean fruit mass and the yield of the yellow passion fruit were higher in sandy-loam soil. The total revenue was R$ 4,311.6 ha-1 in the clayey soil and R$ 5,841.9 ha-1 in the sandy soil. The total cost was higher in the clayey soil than in sandy soil. Both soils responded in quadratic function with an increase in the cost as the volume of organic compost was increased, ranging from R$ 12,736.00 ha-1 with 6.3 liters of compost per hole up to R$ 26,249.63 ha-1 with 156.9 liters of compost per hole. Net income was negative for all compost volumes in both types of soil, responding linearly, with a reduction in revenue of R$ 80.82 ha-1 with the addition of each liter of compost in the pit due to the low yield caused by period long drought.

Phosphorus Sources Combined with Doses of Organic Compost Increased the Population of Soil Microorganisms and P Level in the Soil and Plant and the Dry Matter of Sugarcane

The aim of the study was to evaluate the effect of P sources and filter cake, enriched or not with biofertilizers and liquid peat, on the microbial population and the soil available P levels and shoot dry matter and P accumulation by sugarcane. The experiment was conducted in a greenhouse in a completely randomized design with factorial arrangement 4 × 3 + 1 and three replications. The treatments consisted in four sources of P: simple superphosphate, triple superphosphate, monoammonium phosphate and reactive natural phosphate combined with three levels of organic compound: without filter cake, decomposed filter cake (30 t ha−1, dry basis) and decomposed filter cake enriched with liquid peat (4 mL kg−1 of filter cake) and biofertilizers (480 mL kg−1 of filter cake) and a control treatment without organic compound and without phosphorus. At 45 and 110 days after planting the total population of bacteria and fungi, phosphate-solubilizing microorganisms and total microorganisms were evaluated. After 60 and 110 days, the soil available P, plants’ P and dry matter and P accumulation were evaluated. The organic compound increased the population of soil microorganism, the soil P levels, the accumulation of P and dry matter by the plants, regardless of the source of P, although the enrichment with biofertilizer and liquid peat did not enhance this effect. In conclusion, the presence of organic compost enhances the effects of phosphate fertilization.

MINERALIZATION OF NITROGEN AND CARBON FROM ORGANIC COMPOST FROM ANIMAL PRODUCTION WASTE

ABSTRACT Elucidating the mineralization of organic composts makes it possible to understand the release of nutrients to plants. The objective of this study was to evaluate the mineralization of nitrogen (N) and carbon (C) from organic compost from residues of the production and slaughter of small ruminants, applied on a Neossolo Flúvico (Fluvents). The compost consists of remains of grass (forage), manure and slaughter residues such as blood, viscera and the carcass of goats and sheep. Under laboratory conditions, two experiments were conducted in a completely randomized design, considering the doses of organic compost at the following levels: zero; 3.75, 7.5, 15 and 30 Mg ha-1. For the N and C mineralization tests, 11 and 32 collection times (sampling periods) were evaluated, respectively. Inorganic N content (ammonium and nitrate) was measured in the N mineralization test, and CO2-C concentration was quantified in the C mineralization test. The largest increments between the applied doses of organic compost from residues of the production and slaughter of small ruminants were 70% and 69% for potentially mineralizable N and C, with amounts of 7.5 and 30 Mg ha-1 at doses of 3.75 and 7.5 Mg ha-1, respectively. Organic C and N from residues of the production and slaughter of small ruminants are rapidly mineralized in the soil (up to 45 days) due to their low C/N ratio.

Growth and Nutritional Status of Passiflora edulis f. Flavicarpa, With the Application of Organic Compound in Amazonian Soil

Growth with organic fertilizers has increased in recent years because of the beneficial effect of organic matter on intensely cultivated soils and the high costs of mineral fertilizers. In order to evaluate the effects of organic compost doses produced from family farming waste on the growth and nutritional status of the passion fruit, an experiment was carried out in a greenhouse at the Universidade Federal Rural da Amazônia, in Belém, State of Pará, in the period from March to June, 2012. The experimental design was completely randomized, with five treatments and four replications, with each experimental plot made up by a pot with a volume of 3.6 dm3 of soil and a yellow passion fruit seedling. Five doses of organic compost (0%, 15%, 30%, 45%, and 60%) were tested out of the total volume of the substrate. The compost was formed by mixing 10% poultry litter, 20% duck litter, 15% manioc husk, 15% cassava leaf, 15% bean straw, 15% rice husk, and 10% corn cob. The different amounts of organic compost were mixed in volumetric proportions of substrate of Yellow Latosol with a sandy texture, taken from the surface layer (0-20 cm). It was found that at 97 days, the best results were achieved at the dose of 60% of the compost. The content and accumulation of macronutrients in the foliar tissue of the yellow passion fruit plants followed this descending order: K > N > Ca > P > Mg ≥ S.

Mineral and organic fertilization affects Tetranychus urticae, pseudofruit production and leaf nutrient content in strawberry

The aim of this study was to evaluate the population of Tetranychus urticae Koch (Tetranychidae – twospotted spider mite - TSSM) submitted to mineral fertilizer or crescent doses of organic compost (OC) and find its correlation with nitrogen, potassium and phenolic compounds in strawberry leaves. Production were also evaluated. Plants were cultivated in pots, in a greenhouse, for two strawberry crop cycles. Treatments were: mineral fertilization; 0.5, 1.0, 1.5, 2.0 kg of OC plant−1, and control (no fertilization). Mobile TSSM forms on young leaves were evaluated. Production were evaluated by weighting ¾ red (mature) pseudofruits. Levels of nitrogen (N), potassium (K) and total phenolic content were also measured. Plants cultivated with mineral fertilization had higher TSSM populations and foliar nutrients and lower level of phenols. In the first experiment, a higher incidence of TSSM was observed on mineral fertilized plants and plants fertilized with higher dose of OC, compared to other treatments. In the second experiment, higher TSSM incidence was observed on mineral fertilizer plants compared to 1.0, 1.5 and 2.0 kg of OC plant−1. Positive correlation between foliar nitrogen and TSSM populations and negative correlation between phenolic compounds and TSSM populations were found. Mineral fertilized plants presented higher TSSM population than OC fertilized plants despite of similar levels of N in the leaves. Pseudofruits production were higher with 1.5 OC plant−1 fertilization on both cycles.

Strategy for phytomanagement in an area affected by iron ore dam rupture: A study case in Minas Gerais State, Brazil

In 2015, the Fundão tailing dam collapsed over the district of Bento Rodrigues (Mariana, Minas Gerais, Brazil) causing deaths, hundreds of homeless families and incalculable environmental degradation. Environmentally, economically and socially sustainable strategies are needed for the recovery of the affected areas. The main goal of this study was to evaluate the development, biomass production and toxic mineral elements absorption of three species of aromatic grasses (Chrysopogon zizanioides, Cymbopogon citratus and Cymbopogon winterianus). These three species were planted on polypropylene pots filled with the iron ore tailings collected from the topsoil of the Bento Rodrigues district. The pots were fertilized with increasing doses of organic compost associated with mycorrhizae as a phytomanagement strategy. A 4 × 2 factorial scheme was used. The seedlings were fertilized with four doses of organic compost, with or without mycorrhizae. At the highest dose of the organic compost (2 kg.plant−1), the total dry matter (dry matter of the aerial part + dry matter of the roots) for C. zizanioides was 4.5 times higher than the control (tailing only). For C. winterianus and C. Citratus was 3.8 and 2.8 times higher than the control, respectively. Inoculation with mycorrhizae improved biomass production, especially in C. zizanioides. The Fe and Mn levels found in the aerial part of the plants fertilized with organic compost were lower than those just growing on the iron ore tailings for the three species, which suggest that the organic matter apparently helped the plants in the exclusion of the hazardous substances and therefore increased the tolerance to these adverse environmental conditions. C. zizanioides, associated with organic matter and mycorrhizae, would be the recommended species. The proposed phytomanagement strategy can have a significant contribution to the gradual recovery of the affected area and also serve as a source of income for the local population.

Inoculation with arbuscular micorrizhal fungi and organic compost from cocoa shell positively influence the growth and mineral nutrition of soursop plants (Annona muricata l.)

Abstract The aim of this study was to evaluate the effect of arbuscular mycorrhizal fungi inoculation (AMF - Acaulospora scrobiculata, Acaulospora colombiana and the mixture of these inocula) and doses of organic compost obtained from cocoa shell (0, 5, 10, 20 and 30 g dm-3) on “Morada” soursop seedlings. The experimental design was a randomized block with 4 blocks in a 5 x 4 factorial scheme (AMF x organic compost). After 120 days of growth, it was observed that AMF inoculation increased height, stem diameter and shoot, root and total dry biomass. Organic compost stimulated mycorrhizal colonization and the number of spores with the addition up to 10 g dm-3. Mycorrhizal inoculation promoted increases of P content in soursop leaves. Control plants did not show adequate response to doses of the organic compost applied and it was concluded that AMF inoculation combined with organic compost increased the growth and nutrition of soursop plants.

Use of Organic Compost for the Fertilization of Piatã and Paiaguás Grasses: Effects of Dose on Morphogenetic, Structural, Nutritional, and Productive Characteristics

ABSTRACTThe use of organic compost in pasture fertilization is a form of recycling nutrients contained in waste and reducing chemical fertilizer use. To perform pasture fertilization, however, grass responses to doses of organic composts must be known. Thus, the objective of this study was to find the best dose of laying hen organic compost to maximize the productive, morphogenetic, structural, and nutritional responses of Paiaguás and Piatã grasses. A completely randomized factorial (4 × 2) design was used, composed of organic compost doses (0, 400, 800, and 1,200 kg equivalent N.ha−1) and two cultivars (Piatã and Paiaguás) of Urochloa brizantha grass with three replicates per treatment, assessed during four successive cuts. The parameters evaluated were dry matter yield (DM) of shoots and roots, leaf appearance rate (LAR), leaf elongation rate (LER), phyllochron, pseudoculm elongation rate (PER), final leaf length (FLL), number of green leaves (NGL), and senescence rate (SR). The nutritional value of the grasses was also assessed through contents of dry matter, organic matter, crude protein (CP), neutral detergent fiber (NDF), acid detergent fiber, cellulose, hemicellulose, lignin, and in vitro organic matter digestibility (IVOMD). DM yields of both shoot and root increased due to nitrogen increase and Paiaguás grass had the highest yields (P < 0.01). The best organic compost doses ranged from 640 to 950 kg of equivalent N.ha−1 for most morphogenic and structural grass characteristics. The chemical composition of grasses was not influenced (P > 0.05) by doses of organic compost. Levels of 8.05% CP, 67.10% NDF, and 65.14% IVOMD were observed for cultivar Paiaguás, while for cultivar Piatã these values were 7.58% CP, 70.32% NDF, and 63.38% IVOMD. It is concluded that high doses of an organic compost are required (in equivalent N) for cultivars to reach the highest growth rates and that Paiaguás grass has higher dry matter yield, higher growth rates, and better chemical composition when compared to Piatã grass in similar organic fertilization conditions.

Management of Meloidogyne javanica in Okra Using Compost of Pequi Fruit Waste

Pequi waste added to soil can lead to promising results in the management of plant nematodes. This study evaluated the effect of organic compost of pequi fruit waste in the control of Meloidogyne javanica in okra plants. The compost was comprised of cattle manure, sugarcane straw, and pequi rind waste in the ratio 1:1:1. Treatments were five doses of organic compost (0, 5, 10, 20, and 30 g dm-3) and two additional controls: manure (20 g dm-3) and mineral fertilizer (100 mg dm-3 of N), arranged in randomized block design with 10 repetitions. Different treatments were incorporated into pots containing 3 dm-3 of sandy soil infested with 5,000 eggs of M. javanica. Seedlings were transplanted five days later, and evaluated after 60 days of transplanting. Organic compost with pequi waste incorporated to soil increased shoot dry weight and root weight, and reduced the number of egg masses, galls and eggs of M. javanica per gram of root, and reproduction factor. Doses of 20 and 30 g dm-3 increased plant development and reduced the reproductivity of M. javanica compared to mineral fertilizer.

Residual effect of organic fertilization on radish production

ABSTRACT this research aimed to evaluate the residual effect of doses of organic compost on the radish production, as well as its effect on soil chemical properties. experiments were conducted in two areas (“low” and “high” soil fertility). prior to this, these areas were first used to evaluate the influence of organic compost doses on endive production. after harvesting endive, radish seeds were sown into the same plots used for endive to evaluate the residual effect. the six treatments consisted of organic compost doses (0, 35, 70, 105, 140 and 175 t ha-1), evaluated in a complete block experimental design, with four replications. vegetative characteristics of radish plants (shoot, root and total fresh and dry matter weight, plant height and root diameter) and soil characteristics (macronutrient content, ph, h+al, organic matter, sum of bases, cation exchange capacity and base saturation) in two dates (11 days after the endive transplant and at the end of the radish cycle) were evaluated. no significant difference was observed for all doses of organic compost in the “low” soil fertility area, obtaining only non-commercial roots (average fresh weight of 5.01 g per root). in the “high” soil fertility area, the higher the organic compost doses, the higher the values of most vegetatitve characteristics of radish plants and the chemical properties of the soil in both dates. for root fresh weight, the values ranged from 4.63 to 9.15 g in the control without organic compost and in the highest dose, respectively. in “high” soil fertility area, only k content in soil has not remained high for all organic compost doses, and the values ranged from 2.8 and 4.5 mmolc dm-3, in control without organic compost and in the highest dose, respectively. the residual effect of organic compost was confirmed by the increasing on the radish production in initial “high”soil fertility area.

Production and nutrients accumulation of endive under different doses of organic compost

This research aimed to evaluate the effects of doses of organic compost on the production and macronutrients accumulation of endive plant in two areas with different fertility levels. The experiments were conducted at the Experimental Farm Sao Manuel, located in the municipality of Sao Manuel-SP. The study was done in a complete random experimental design with seven treatments and four replications. The treatments consisted of different doses of organic compost (0, 35, 70, 105, 140 and 175 t ha -1 ) and a treatment with inorganic fertilizer. Vegetative characteristics (shoot fresh and dry matter weight, number of leaves, plant height and nutrients accumulation in the aerial part of the plant) were evaluated at the end of the cycle. It can be concluded that the higher the organic compost dose (in the studied range), the higher the production (shoot fresh weight) and nutrients accumulation of endive in either high and low fertility area. In the aerial part, the decreasing order of nutrients accumulation was: potassium > nitrogen > calcium > phosphorus > sulphur > magnesium, with the highest values of 1269, 471, 185, 91, 53 and 35 mg plant -1 , respectively.

Doses of organic compost on yield and accumulation of macronutrients on endive

ABSTRACT The authors evaluated the effects of doses of organic compost on the production and accumulation of macronutrients in endive plants in two areas with different fertility levels. The experiments were carried out at Fazenda Experimental São Manuel, located in the municipality of São Manuel, São Paulo State, Brazil. The study was carried out in a completely randomized design with seven treatments, six doses of organic compost (0, 35, 70, 105, 140 and 175 t/ha) and one additional treatment with inorganic fertilizer (N-P-K 4-14-8) and four replicates. In both areas, when the dose of organic compost was increased, the authors noticed a linear increase in fresh matter weight, number of leaves and plant height. In high-fertility area, compared to control (dose 0), using the highest dose (175 t/ha), the authors observed an increase of 280, 58 and 101% in fresh matter weight, number of leaves and plant height, respectively. For dry weight, we observed a linear increase in low fertility area and quadratic effect in high fertility area, with maximum estimated dry matter of 22.26 g applying 144 t/ha of organic compost. The nutrient accumulation was proportional to dry matter, with a linear increase in low fertility area and quadratic effect in high fertility area. The decreasing order of accumulated nutrients was K&gt;N&gt;Ca&gt;P&gt;S&gt;Mg, with the highest values, in high fertility area, of 1,269, 471, 185, 91, 53 and 35 mg/plant, respectively, for doses varying from 121 to 158 t/ha.

Structural characteristics of elephant grass fertilized with organic composted waste from production and slaughter of small ruminants

This study aimed to evaluate the morphophysiological characteristics of irrigated Pennisetum purpureum cv. Cameroon subjected to doses of an organic compost from waste generated by production and slaughter of small ruminants. The experiment was carried out in a grassland, during four growth cycles of 60 days. The area is located in the Embrapa Caprinos e Ovinos unit, in Sobral - CE, Brazil. Treatments consisted of organic compost doses (0, 13.3, 26.6, 39.9, 53.2 and 79.8 Mg ha-1) plus a mineral fertilization (nitrogen and potassium) at doses equivalent to 720 and 900 kg ha-1 year-1, respectively. The experimental design was arranged in completely randomized blocks, totaling four blocks with seven treatments each, in a split plot scheme with repeated readings over time. The plots corresponded to seven doses of an organic compost and an additional treatment (mineral fertilizer), and subplots to four growth cycles. The variables analyzed were total herbage biomass (THB), canopy height (CH), tiller population density (TPD) and water use efficiency for green leaf biomass production (WUEGLB) and green stem biomass (WUEGSB). In the first cycle, TPD decreased linearly with increasing doses of the compost, with 47 tillers m2 at the dose of 79.8 Mg ha-1, while THB and WUEGLB variables behaved quadratically, with a maximum point of 23.53 Mg DM ha-1 cycle-1, and 16.33 kg DM mm-1 for the doses of 66.52 and 62.94 Mg ha-1 of the organic compost. We concluded plant structural characteristics and water use efficiency were responsive to applications of the organic compost, and we recommend the dose of 67.7 Mg ha-1.