Concentrations Of Biofertilizer Research Articles

Increasing Concentrations of Arthrospira maxima Sonicated Biomass Yields Enhanced Growth in Basil (Ocimum basilicum, Lamiaceae) Seedlings

The continued increase in human populations and use of chemical fertilizers remain a threat to the health and stability of human–ecological systems worldwide. To ameliorate this problem and achieve long-term food security, a variety of ecofriendly technologies have been developed, including the production of cyanobacteria-based biofertilizers. This technology can be optimized through experiments that assess how plant growth is enhanced under different biofertilizer concentrations (g L−1). In this study, the biofertilizer capabilities of various concentrations of sonicated biomass (0, 2.5, 5, 10, 20, and 40 g L−1) derived from the cyanobacteria Arthrospira maxima on the growth of basil (Ocimum basilicum, Lamiaceae) were assessed, comparing their effectiveness with that of a positive control, a commercial biofertilizer (OptiMar Algas Marinas®) administered at 4 mL L−1. Generally, increased concentrations led to enhanced growth parameters; however, discernible differences from the negative control (0 g L−1) were often observed only when concentrations exceeded 5 g L−1. Surprisingly, the negative and positive controls often yielded similar results. A chemical composition analysis of A. maxima revealed high concentrations of the phytohormones, macronutrients, and essential amino acids that likely explain how our A. maxima sample enhanced growth in basil. Further research is required to determine how other crop plants respond to different concentrations of A. maxima. Additionally, assessing the feasibility of creating an economically accessible product with a higher concentration of A. maxima is crucial for practical applications.

Application technique and concentration of biofertilizer from rhizosphere of cocoa (Theobroma cacao L.) given biosurfactant dietanolamide oil palm on the growth of cocoa seedlings

This research aimed to know the influence of application technique and biofertilizer that given concentration of biosurfactant diethanolamide (DEA) for the growth of cocoa seedlings and also to know the interaction between application technique and concentration level of biofertilizer given DEA growth of cacao seedling (Theobroma cacao L.). This research was conducted in UPTD SITANDU, Banten and the Soil Agroclimate Laboratory, Faculty of Agriculture, University of Sultan Ageng Tirtayasa from December 2020 until March 2021, by using randomize complete block design with two factors. The first factor is technique application T1 at soil, T2 at leaf, and T3 with combination soil and leaf fertilization), and the second factor is concentration level of biofertilizer given DEA P1 10 ml and 5%, P2 10 ml and 10%, P3 20 ml and 5%, P4 20 ml and 10%. As a result, there were twelve possible treatment combinations, and each was applied three times. Parameters total chlorophyll (unit), root length (cm), stem diameter (mm), seedlings dry weight (g) and root shoot rasio (g). The results there was no interaction effect between the two treatments, namely application technique and concentration level of biofertilizer with DEA biosurfactant, on all observed parameters of cocoa seedlings.

Greenhouse crops of radish under organomineral fertilization sources in the Brazilian semiarid region

The cultivation of radish in an organic system has potential for production to such a degree that alternatives of cultivation have been used to improve productivity in relation to fertilization. Therefore, the objective of this work was to evaluate the effect of organomineral fertilization on gas exchange, growth, and production of radish. The experiment was carried in non-climatized greenhouse crop, with a metallic structure in form of arc, covered with 150 mm low-density polyethylene, in greater length-oriented East-Oste direction of Science and Technology Center of Federal University of Campina Grande, using the Crimson Gigante variety. The soil used experiment was fluvic neosol. The experimental design used was the completely randomized with three replications, using the Crimson Gigante variety. Seven treatments were used, which consisted of three doses of cattle manure (37.5; 75.0, and 150g per pot), three concentrations of biofertilizer (5; 10 and 15%), and mineral fertilization. This work analyzed the characteristics of growth, production, and gas exchange. The treatment (5% biofertilizer) provided greater height of the radish plants, however, the (75.0g manure per pot) resulted in a higher number of leaves. The concentration of 10% of the biofertilizer, obtained the largest diameter, fresh and dry matter of the tuberous root. The treatment presented higher fresh and dry matter of the leaves when compared with the other treatments. The use of organic fertilizers promoted greater production in the radish crop and can be used as an alternative to conventional fertilization.

Improving the Chemical Content and Mineral Elements of Drought Stressed (Moringa Oleifera L.) by Application of Glutathione and Bio-Fertilizer

The experiment was carried out in pots with a capacity of 28 kg in the Department of Horticulture and Landscape Engineering - College of Agriculture - the University of Karbala in order to know the extent of the effect of glutathione and biofertilizer and to determine the best concentration of these treatments in reducing the harmful effect of water stress in terms of the content of enzyme antioxidants and active substances and determine The best irrigation level for this plant without harming the plant and determining the best concentration of glutathione and biofertilizer in reducing the harmful effects of water stress on the Moringa plant, as the study included three factors: glutathione with three concentrations (0, 100, 200) mg. L-1 and biofertilizer (Algacell) at two levels (0 and 10) mg. L-1 and water stress have three field capacity levels (60%, 50%, and 40%). The experiment was carried out using Dunkin’s multinomial test at a probability level of 0.05. The data were analyzed according to the statistical program (SAS 2003), where the results showed that there is a significant effect of glutathione on Most botanical characteristics and mineral element content. Glutathione is an antioxidant that plays a role in plant growth, cell division, and elongation, which protects cells. Water stress affects the dissolution of nutrients and their transfer from soil to plants. The more a plant is exposed to water stress, the more leaves will drop due to the increased ABA concentration. Moreover, the root was longer. Where water stress leads to an increase in the levels of ROS within the plant cells, which stimulates the plant to resist and remove the effect of these free radicals. Moringa is a plant gaining much attention due to its many benefits is a drought-tolerant crop, great for areas lacking water, that can grow in drought-prone regions. It is also a plant that can be used in many different ways, including food, medicine, environmental restoration, and textile products.

Seaweed extract biofertilizer modulates scarlet eggplant tolerance to salt stress

The present study aimed to analyze the application of a seaweed biofertilizer as an attenuator of salt stress on the morphophysiology of scarlet eggplants. The experiment was carried out under protected conditions in Areia, PB, Brazil, using an incomplete factorial arrangement in a randomized block design with four replications and two plants per plot by adopting the Box Central Composite Design with five electrical conductivities of irrigation water – ECiw (0.50 – control, 1.15, 2.75, 4.35 and 5.00 dS m−1) and five concentrations of seaweed biofertilizer (0 – control, 1.45, 5.00, 8.55 and 10 mL L−1). The electrical conductivity of irrigation water at values starting at 0.5 dS m−1 negatively affected the growth of scarlet eggplants. Therefore, the crop is considered sensitive to salt accumulation. The increase in electrical conductivity of irrigation water negatively affected the morphophysiology of scarlet eggplants, with reductions higher than 10% at electrical conductivity values higher than 1.37 dS m−1. Biofertilization at 6.67 mL L−1 mitigates the effects of salt stress on the gas exchange variables and the phytomass accumulation of scarlet eggplants 60 days after sowing. The seaweed biofertilizer can be used to improve the physiological and morphological performance of scarlet eggplants.

The Productivity of Red Chili (Capsicum annum L.) Improvement Using Inorganic Fertilizer and Biofertilizer: Implications for Sustainable Agriculture

Red chili (Capsicum annum L.) is one of the important horticultural crops, yet its productivity is still relatively low. This study aims to determine the productivity of red chili improvement through the use of inorganic fertilizer and biofertilizer. The factorial randomized group design (RAK) experimental design with 2 factors and 3 replicates (10 plants for each replicate) was used in this research. Factor I consisted of four doses of inorganic fertilizer (K), namely: 200 kg/ha (k1), 300 kg/ha (k2), 400 kg/ha (k3), 500 kg/ha (k4). Factor II consists of four concentrations of biological fertilizer (H), namely: 10 ml/L (h1), 20 ml/L (h2), 30 ml/L (h3), 40 ml/L (h4). The results showed that there was no interaction effect between the use of inorganic fertilizer (NPK) and the concentration of biofertilizer (M-Bio) on fruit weight per plant (g/plant) and fruit yield per hectare (t/Ha). However, the single use of biofertilizer with a concentration of 20 ml/L significantly increased the productivity of fruit weight (555.75 g/plant or 14.81 t/Ha). Biofertilizers such as phosphate solubilizing microorganisms and nitrogen-fixing bacteria can increase the availability of macro and micro nutrients in the soil and the productivity of chili significantly. The use of biofertilizers has the benefit of reducing farmers' dependence on inorganic fertilizers. Therefore, the use of a combination of inorganic fertilizer and biofertilizer not only can be a good alternative to increase the productivity of red chili effectively and sustainably, but also to reduce the negative impact of using inorganic fertilizer on the environment.

Effect of Spraying with Glutathione and Bio-Fertilizer (Algacell) in some Growth Characteristics of (Moringa Oleifera L.) Under Water Stress

Abiotic stresses, including water stress, negatively affect the growth and development of plants. The study was carried out in the canopy of the Horticulture and Landscaping Department / College of Agriculture / University of Kerbala during the spring season 2021 in order to study the vegetative growth indicators of Moringa plants (Moringa Oleifera L.) after treatment with glutathione and bio-fertilizer (Algacell) under water stress conditions. The study included exposing moringa seedlings to water stress at three field capacities (40%, 50%, 60%) of the total field capacity and the seedlings were sprayed with three concentrations of glutathione (0, 100, 200 mg. L-1) and two concentrations of biofertilizer (0, 10 mL. L-1). The factorial experiment was designed according to a randomized complete block design (R.C.B.D). The results showed that spraying plants with a concentration of 200 mg. L-1 glutathione gave a significant increase in the traits (stem diameter, leaf area, chlorophyll) and this treatment did not differ significantly from (100 mg. L-1) in the traits (plant height, number of leaves, relative moisture content), while no Biofertilizer had no significant effect on most of the studied traits. The results also showed the contribution of glutathione in reducing harmful effects and helped the plant to withstand water stress conditions.

Effect of the Application of Biofertilizer Goatish as a Biostimulant on Germination Canavalia Ensiformis L.

Objective: This study aimed to evaluate the influence of different concentrations of goatish biofertilizer as an alternative biostimulant on the germination and vigor of pork bean seeds. Theoretical framework: The availability of complementary nutrients via seeds promotes germination and vigor, since they are fundamental factors for the good development of production. Therefore, the use of alternative technologies as a biostimulant promote better formation and development of the plant. Methodology: The research was carried out at the Seed Technology Laboratory of the Federal University of Paraíba. A completely randomized design was used, with treatments at different concentrations of goat biofertilizer, namely: 0% (control), 25%, 50%, 75% and 100%, where they were immersed for 10 minutes. The substrate used was Germiteste paper, where 30 jack bean seeds were distributed and stored at a temperature of 30 °C for 12 hours of light. The variables analyzed were: germination speed index, germination, primary root length, hypocotyl length, width and length of cotyledons and green and dry mass of the variables mentioned above. Results and conclusion: The application of the concentration of 50 and 75% proved to be efficient in the seed germination process and germination speed index. The 25% concentration of goat biofertilizer provided better performance in the morphological characteristics of jack bean seeds. Research implications: The main contributions of the study are in the sense of demonstrating a different methodology as an alternative biostimulant in the germination and vigor of seeds, which can contribute to researchers and family farmers in overcoming seed dormancy, as well as increasing plant growth and development. Originality/value: This study proposes to evaluate the biofertilizer as a biostimulant in the germination and vigor of jack bean seeds as an alternative for taking advantage of the organic residue.

EFEKTIVITAS PEMBERIAN PUPUK HAYATI BIOBOOST TERHADAP PERTUMBUHAN DAN HASIL TANAMAN TERUNG (Solanum melongena L.)

One of the vegetable plants that is often consumed by Indonesian is eggplant, because it has high nutrition and many health benefits. Eggplant growth and production can be increased by using biofertilizers, such as bioboost biofertilizer. The purpose of this study was to obtain the best concentration of bioboost biofertilizer for the growth and production of eggplant. This research was carried at UIN Sultan Syarif Kasim Riau and Laboratory of Agronomy and Agrostology, Faculty of Agriculture and Animal Science, from March to June 2022. The study was carried out using a completely randomized design (CRD) consisting of 5 treatments (P0 = positive control, P1 = 20 ml L-1 water, P2 = 40 ml L-1 water, P3 = 60 ml L-1 water, and P4 = 80 ml L-1 l water), which repeated 10 times to obtain 50 experimental units. The results showed that there was a significant effect of giving bioboost biofertilizer on the number of fruits, fruit weight, fresh weight, and plant dry weight. The most efficient results for the growth and production of eggplants grown on soil media mixed with chicken manure (2:1 ; w/w) are obtained with the application of bioboost biofertilizer at 20 ml L-1 water.

Pengaruh Konsentrasi dan Interval Aplikasi Pupuk Hayati Terhadap Kandungan N Tanaman, N-Total Tanah, Populasi Bakteri Endofitik, dan Hasil Tanaman Pakcoy (Brassica rapa L.)

The purpose of this research was to analyze the effect of Azolla biofertilizer application on plant N content, total soil N, endophytic bacteria population, and yield of pakcoy on Inceptisol Jatinangor soil. The research was carried out from August until November 2021 at Plastic House of the Faculty of Agriculture, Padjadjaran University, Sumedang with an altitude of ±750 m above sea level. The research was arranged in Factorial Randomized Block Design. The first factor was the concentration of biofertilizer were 5 ml L -1 ; 10 ml L -1 ; 15 ml L -1 ; and 20 ml L -1 . The second factor was application intervals of one time, two times, and three times with three replications. Results showed that no interaction between various concentrations and application intervals of biofertilizer application on all parameters. The concentration of biofertilizer had significant effects on total nitrogen (N) soil, endophytic bacteria population, and yield of pakcoy, but had no significant effect on plant N content. The application intervals of biofertilizer did not affect on all parameters. Furthermore, the treatment of biofertilizer with concentration of 10 ml L -1 gave highest yield on the yield of pakcoy parameter which was 164.89 g but was not significantly different from the treatment with concentration of 15 ml L -1 and 20 ml L -1 .

Assessment of physicochemical characteristics of biofertilizers and their role in the rooting capacity of plants

The concentration of supplied mineral nutrients is one of the most important and limiting factors for enhancing the efficiency of plant nutrition. Optimal concentration of nutrient solutions (NS) provide plants with the necessary amount of nutrients. From this point of view, research on several physicochemical parameters that characterize concentrations of NS and uptake of nutrients by the plants remains an actual problem. The changes of electrical conductivity (EC) and total dissolved solids (TDS) depending on the concentration of biofertilizer as well as the role of biofertilizer solutions on the rooting capacity of cuttings (lateral sprouts) of Callisia fragrans are presented here. The EC and TDS of the biofertilizer-water mixture changed gradually according to the biofertilizer concentration. The biofertilizer solution was a good medium for the rooting of C. fragrans cuttings. The results could help to provide the crops with the necessary amount of mineral nutrients and regulate the suitability of irrigation during the entire vegetation period.

Effects of Microbial Fertilizer on Soil Fertility and Alfalfa Rhizosphere Microbiota in Alpine Grassland

Chemical fertilizers are gradually being replaced with new biological fertilizers, which can improve the soil and soil microorganisms. In this experiment, leguminous forage (Medicago sativa cv. Beilin 201) was used as the research object. By measuring alfalfa root systems and soil properties and using high-throughput sequencing technology, we investigated the effect of biological (rhizobial) fertilizer at different concentrations on soil fertility and alfalfa rhizosphere microbiota in alpine grasslands. The results demonstrated that the treatment with biofertilizer significantly reduced total nitrogen (TN) and total organic carbon (TOC) content in soils, increased root densities, and significantly increased the number of root nodules in alfalfa. There were differences in the response of rhizosphere microorganisms to different concentrations of biofertilizer, and the treatment with biofertilizer led to pronounced changes in the microbial community structure. The abundance of beneficial bacteria such as Rhizobium, Arthrobacter, and Pseudomonas was significantly increased. The Pearson correlation analysis showed that soil moisture and soil conductivity were significantly positively correlated with the observed richness of rhizosphere microbiota (p < 0.05). Meanwhile, Actinobacteria showed a significantly positive correlation with nitrate, TOC, and TN (p < 0.01). These results indicated that biofertilizers enhanced soil fertility and altered the rhizosphere microbiota of alfalfa in alpine grassland.

Use of bovine biofertilizer in cabbage production in alley system

Cabbage cultivation with organic inputs in agroforestry systems may be an alternative for cultivation in the state of Roraima. In this context, the objective of this study was to evaluate the effects of bovine biofertilizer and alley system on the production components of Sooshu hybrid cabbage. The experiment was conducted from August 2019 to July 2020 at the Agrotechnical School of the Federal University of Roraima. The treatments were arranged in randomized blocks, in split plots, with three replicates. The factorial scheme used was 2 × 5, referring to production in systems without and with alleys and five concentrations of bovine biofertilizer (0, 25, 50, 75 and 100% of the 8 L m-2 dose). After 113 days of application of the bovine biofertilizer, the following were evaluated: i) mass of the leaves that form the head; ii) number of outer leaves; iii) mass of outer leaves; iv) transverse and longitudinal diameters and v) yield. The agroforestry system had no influence on cabbage production components. Bovine biofertilizer at concentration of 63.13% promoted higher mass of leaves that form the head and yield of Sooshu hybrid cabbage.

Effect of algae and Bio-fertilizers on some growth characteristics and yield of wheat Triticum aestivum L.

The experiment was carried out in the wooden canopy which belongs to the Soil and Water Department/ Technical College- Al-Mussaib/ Mashru Al-Mussaib area/ Babylon Governorate, during winter season 2020. The study aimed to know the effect of three concentrations of (0, 2.5, and 5 ml.L-1) of algae fertilizer (Biozyme TF) and three concentrations (0, 1.5, and 3 ml.L-1) of bio-fertilizer (EM1) and their interactions on the growth and yield of wheat crop. A factorial experiment was applied according to the Randomized Complete Block Design (RCBD) with three replicates. The results revealed that the addition of algae fertilizer (5 ml.L-1) and spraying with bio-fertilizer (3 ml.L-1) individually led to a significant increase in all characteristics of vegetative growth and yield components (plant height, area of flag leaf, number of spurs, length of spike, number of grains / spike and the weight of 1000 grains). Moreover, the dual interaction between the two factors of the study significantly affected most of the studied traits except (plant height and spike length), where the combination between (5 ml.L-1 algae fertilizer + 3 ml.L-1 biofertilizer) was superior in giving the highest averages, while the comparison treatment gave the lowest averages. It can be concluded from this study that it is possible to rely with a high percentage on the use of environmentally friendly biological extracts as part of the fertilization program for field crops, including wheat.

Effects of cultivation conditions on Chlorella vulgaris and Desmodesmus sp. grown in sugarcane agro-industry residues

Large-scale microalgae cultivation is often associated with high costs, and nutrients account for a significant part. However, the use of cheaper nutrients, carbon, and water sources could reduce expenses. This study aims to produce Chlorella vulgaris and Desmodesmus sp. cultivated in sugarcane biorefinery residues bagasse and vinasse. A biofertilizer from bagasse biochar was produced and characterized, and a pre-treatment by filtration was performed on vinasse. The effects of varying growth conditions (antibiotic, vinasse, and biofertilizer concentrations; air flowrate; pH; light intensity; and photoperiod) were discussed based on the results of a Plackett-Burman design. The highest cell density was achieved by Desmodesmus sp. (46·106 cells mL−1 from an initial 6.5·106 cells mL−1) using vinasse (20%) and biofertilizer (1 g L-1). Specific metabolite accumulation was also observed. Under stress conditions, 21.3% lipids and 51.0% carbohydrates were obtained for two different cultivations. Using 1 g L-1 of biofertilizer, biomass composition had 74.8% proteins.

DESENVOLVIMENTO DO GIRASSOL SOB DOSES DE BIOFERTILIZANTE BOVINO EM CULTIVO AGROECOLÓGICO

Sunflower production in the Northeast is still incipient. It would be an important challenge for Piaui to produce sunflower, in quantity and quality, as it would certainly add to the State's agricultural GDP, especially with regard to the production of edible oil, extracted from achenes. The effects of a liquid bovine biofertilizer on sunflower growth and biomass under agroecological cultivation were analyzed. The experiment was carried out in DIC, with five treatments and six repetitions, totaling 30 experimental units. The four treatments with the biofertilizer were 50, 75, 100 and 125% of the optimal recommendation, and the control (without application). It was analyzed: plant height (AP), stem diameter (DC), chapter diameter (DCAP), shoot dry matter production (MSPA) and root system (MSSR). The results were subjected to analysis of variance and later regressions were performed. Despite the non-significant results, the sunflower plants that received the biofertilizer showed better performance when compared to plants that did not receive the liquid organic input; furthermore, in the variables AP and MSSR, the best results were found in plants that received the highest concentrations of biofertilizer. As for the other variables, the maximum points (concentration of biofertilizer) were between 79 and 167%, with a suggestion of toxic effect in more concentrated doses of the organic input.

Effectivity of Biofertilizer and shoot pruning on yield of cocoa (Theobroma cacao L)

This study aims to understand the effectiveness of biofertilizers and shoot pruning in improving cocoa growth and yield. The research was conducted in the “Kebun Dinas Bone-Bone”, North Luwu Regency, South Sulawesi Province from February to August 2020. This research was conducted in the form of an experiment arranged in randomized block design (RBD) with 3 replications. The treatment consist of 10 levels, namely: without biofertilizer and not shoots pruned, biofertilizer 9 ml L−1 per tree and not shoots pruned, biofertilizer 18 ml L−1 per tree and not shoots pruned, biofertilizer 27 ml L−1 per tree and not shoots pruned, biofertilizer 36 ml L−1 per tree and not shoots pruned, biofertilizer 0 ml L−1 per tree and shoots pruned, biofertilizer 9 ml L−1 per tree and shoots pruned, biofertilizer 18 ml L−1 per tree and shoots pruned, biofertilizer 27 ml L−1 per tree and shoots pruned, biofertilizer 36 ml L−1 per tree and shoots pruned. Research results show that the concentration of biofertilizer of 32 mL L−1 gave the highest value for number of pods (10 pods), 42.8 seeds of fruits, and yield 0.71 kg per tree or equivalent to 591.67 kg/ha of dry seeds. Pruning the shoots gave the highest number of seeds per fruit of 36.82 and pod index of 20.

Development of immobilized matrix from durian rind waste in cultivation of microalgae for biofertilizer production

Conventional fertilizers have a negative impact on environment and are not economically efficient. This is because the fertilizers are lost by volatilization in the atmosphere, leaching into the groundwater or fixation in the soil. The aim of this project is to produce a new generation of biofertilizers, using an eco-friendly coating based on biomass and biopolymers derived from pectin. In this study, pectin from durian rind was obtained after a treatment with an acidified solution followed by purification through alcohol precipitation. The durian pectin was found to be 3.22 ± 0.065% of methoxyl content which is classified as a low methoxyl pectin. Therefore, it is suitable to be used as a biopolymeric matrix to produce a slow-release soil fertilizer added with microalgal (Scenedesmus sp.) biomass residue. The incorporation of sodium alginate as a gelling mixture was found to enhance the formation of rigid bead structure. The morphology of encapsulated Scenedesmus-beads were then examined using scanning electron microscopy and the growth of Abelmoschus esculentus (Okra plant) was observed for its potential use as biofertilizer. The results obtained for the morphology of the beads shows that the beads have a porous structure. In just two weeks, the significant growth of plant treated with biofertilizer was shown by having a much greater height (7.17 + 1.04 cm), number (4 leaves) and size of leaves (3.67 ± 0.32 cm) compared to the control (5.17 + 0.35 cm high, 3 leaves, and 2.67 ± 0.20 cm in size, respectively). However, further research is needed on the optimal biofertilizer concentration and dosage as well as on the kinetic study of the release compounds from the beads. Overall, this article exhibits a good perspective for alternative fertilizer for agriculture applications and represent an innovative solution for durian rind final disposal.

Gas exchange and photosynthetic pigments in zucchini plants under cattle bio-fertilization and sources of nitrogen

Zucchini is traditionally used in human consumption, however, the scarcity of information, especially about fertilization and the physiological aspects of this crop, constitutes a major obstacle its cultivation and commercialization. The objective was evaluate the chlorophyll content and gas exchange under cattle bio-fertilization and different sources of nitrogen. The work was carried a randomized block experimental design was used in a factorial scheme 5 x 3 + 1 composed of five cattle bio-fertilizer concentrations, three sources of nitrogen and an additional treatment without nitrogen. The levels of chlorophyll a, b and total, liquid photosynthesis, transpiration, internal CO2 concentration, stomatal conductance, instantaneous water use efficiency, and instantaneous carboxylation efficiency were evaluated. The studied variables were influenced by the interaction between the concentrations of the cattle bio-fertilizer and the nitrogen sources, except for the chlorophyll b content and the instantaneous water use efficiency, which responded only to the nitrogen sources. Ammonium sulfate and urea increased increase the physiological variables evaluated. The combination of ammonium sulfate with bio-fertilizer promoted an increase in chlorophyll a, total chlorophyll, liquid photosynthesis, transpiration, internal carbon concentration, stomatal conductance, and instantaneous carboxylation efficiency. The cattle bio-fertilizer in the soil without nitrogen did not increase the physiological variables evaluated.

Bokashi compost and biofertilizer increase lettuce agronomic variables in protected cultivation and indicates substrate microbiological changes

The aim of the study was to evaluate agronomic productive variables of iceberg lettuce and soil microbiological variables for two crop cycles by using organic inputs. The treatments were as follows: control (no fertilization); Bokashi compost (20 g per plant); Penergetic-k plus Penergetic-p bio-activators (both at 1.5 g per litre of water, applied to the substrate and plant, respectively); and biofertilizer at different concentrations (2.5, 5.0, 7.5, and 10% dilutions in water). Biofertilizer concentrations were applied during five fertigation times per day in the first crop experiment and in single daily fertigation in the second crop experiment. Agronomic productive variables evaluated were: total mass, commercial mass, discarded leaves mass, stem diameter, commercial head diameter and plant height. Soil microbial biomass carbon, basal soil respiration and metabolic quotient were evaluated for substrate microbial quality measurement. In the first cycle, plants treated with Bokashi or Penergetic presented superior total mass, commercial mass and commercial head diameter of lettuce, while plants treated with biofertilizer did not exhibit improvement and presented tipburn in some plants, when compared to control. In the second cycle, the use of Bokashi and biofertilizers improved the total mass and commercial head diameter, compared to control. Higher than control microbial biomass was achieved with biofertilizer concentrations and Bokashi. Lower metabolic quotient (qCO2) was observed for all the treatments, when compared to control. Soil microbial quality data corresponded to better lettuce yields.