Root Fresh Mass Research Articles

Radish cultivation with hydrogel doses combined with different water slides in drip irrigation system

Radish yield and quality are factors influenced by water stress that may occur during periods of drought or irrigation handled inappropriately, interfering negatively in plants development, producing radishes of inferior quality and in lesser quantity. In addition to irrigation, which makes water available in the system, it is important to maintain it with the use of water-retaining products such as hydrogel. The aim of this work was to evaluate radish yield, submitted to three different hydrogel doses combined with two water slides. The experimental design was in factorial scheme 3 x 2, with three water slides (50%, 75% and 100% Eto – reference evapotranspiration estimate) and two hydrogel doses (40 and 60 g m-2) with four replicates. Number of leaves, horizontal and vertical root diameter (mm), total and shoot length (cm), fresh mass of root and shoot (g), dry mass of shoot and root (g) and yield (t ha-1) were evaluated. The best results, regarding radish production and development, were obtained when using 50% of Eto with 60 g m-2 of hydrogel in combination. Thus, radish cultivation in oxisoil was influenced by the use of hydrogel, which provided a more efficient water level use.

Water availability and substrate in the emergency and initial development of Bauhinia scandens L.

Bauhinia scandens is an ornamental plant and it has anti-tumor properties. The demand for seedlings of this species makes it necessary to know about the germinative behavior of seeds and the initial growth of seedlings. The objective of the present work was to determine the type of substrate and moistening conditions that are more favorable to the emergence and development of seedlings of B. scandens. B. scandens seeds were disposed on three substrates: sand, vermiculite, and commercial substrate, maintained at four levels of moistening 25, 50, 75, and 100% of the water holding capacity of the substrate and kept in a greenhouse for 60 days. The following parameters were evaluated: emergence, speed index, average time, number of leaves, length of aerial part and root, diameter of neck, fresh and dry mass of aerial part and root. The analysis of variance was performed in a completely randomized design, in a 3 X 4 factorial scheme, with four replications of 25 seeds. The sowing of B. scandens should be carried out initially in vermiculite with a holding capacity of 100% until the establishment of the seedling emergence and then transplanted to commercial substrate keeping between 50 and 75% holding capacity.

Effect of Spent Button Mushroom Substrate on Yield and Quality of Baby Spinach (Spinacia oleracea)

Disposal of spent mushroom substrate (SMS) generated after mushroom cultivation is a subject of great concern. Unplanned disposal causes land, water, and air pollution together with the nuisance in the surroundings. During recent years, environmental legislation has forced mushroom growers to think about more amicable ways of SMS disposal. Hence, farmers in different corners of the country are using SMS as manure for various field crops and horticulture but without any support of the recommended rates from scientific data and therefore may not be getting the optimum benefits. This study sought to evaluate the effects of spent mushroom substrate on the yield and quality of baby spinach. The experiment was conducted in Mazowe, Zimbabwe, with 5 treatments (10 t ha−1, 20 t ha−1, 30 t ha−1 of SMS, and two controls) arranged in a CRBD and replicated 3 times. Biomass production (fresh mass, dry mass, root length, fresh root mass, and dry root mass) and sensory evaluation were determined 35 days after planting. Results showed that increasing rates of spent mushroom substrate significantly ( p < 0.05) increased the fresh yield and quality of baby spinach. Application of spent mushroom substrate beyond 30 t ha−1, however, increased the bitterness of baby spinach. The results of the study present the potential of the spent mushroom substrate as an organic fertilizer for the production of quality baby spinach.

Growth response of Oryza sativa seedlings to graphene oxide and its variability among genotypes

With the extensive utilization of graphene nanomaterials, they inevitably enter our environment. The potential phytotoxicity and environmental impact of graphene oxide (GO) have recently attracted much attention. We designed the experiment based on seed germination, seedling morphology, physio-biochemical properties, and antioxidant enzyme activities of five rice genotypes (9311, MH63, R527, K866, and Nipponbare) under six concentrations of GO (0, 5, 10, 50, 100, and 150 mg dm-3). We studied the effects of different concentrations of GO on germination index (GI), shoot length (SL) and root length (RL), adventitious root number, shoot and root fresh masses, root/shoot ratio, chlorophyll (Chl) content, malondialdehyde content, and activities of superoxide dismutase (SOD), catalase (CAT), and peroxidase (POD). Graphene oxide treatments significantly enhanced seed germination and root growth and inhibited shoot growth of all genotypes. Furthermore, we found a significant genotype-dependent response to GO treatments. According to the relative increment trend of GI, SL, and RL, root/shoot ratio, antioxidant enzyme activities (CAT, POD, and SOD), and Chl content, 'R527' showed more tolerance to GO treatments than the other four genotypes. The 'MH63' and 'K866' were more sensitive than 'Nipponbare' and '9311'. It indicates that the GO-tolerant genotype might avoid free radicals damage from GO by increased antioxidant enzyme activities. Moreover, we should consider the genotype differences when evaluating the potential phytotoxicity of GO and environmental risk to ecosystems.

Salicylic acid-mediated alleviation of soil boron toxicity in Mentha arvensis and Cymbopogon flexuosus: Growth, antioxidant responses, essential oil contents and components

Boron (B) toxicity is a notable abiotic hindrance that restricts crop productivity by disturbing several physiological and biochemical processes in plants. This study was aimed to elucidate the role of salicylic acid (SA) in conferring tolerance to B stress in Mentha arvensis and Cymbopogon flexuosus. Boron toxicity led to a considerable decrease in shoot height and root length, fresh and dry mass of shoot and root, and physiological and biochemical parameters. However, exogenously applied SA relieved the adverse effects caused by B toxicity and led to an increase in growth parameters under B stress and non-stress conditions. The treatment of B resulted in its increased accumulation in roots and shoots of both the plants which, in turn, caused oxidative damage as evident by increased content of malondialdehyde and catalase, peroxidase, superoxide dismutase and glutathione reductase enzyme activities. However, exogenous SA supply significantly affected antioxidant enzyme activities and protected the plants from excess B. Moreover, the essential oil content of two selected plants declined under B toxicity and significantly enhanced in SA-treated stressed plants. The contents of menthol and menthyl acetate in M. arvensis were lowered in B stressed plants which significantly improved in SA treated B-stressed and in their respective SA alone treatment. Similarly, citral-A and citral-B content of C. flexuosus declined under B toxicity, however, SA reversed the negative effects of B toxicity on essential oil components. This assessment stipulated the promising role of exogenously applied SA in alleviating B toxicity in M. arvensis and C. flexuosus by improving antioxidant machinery and limiting B uptake which protects the structural integrity of leaves and also helps in increasing essential oil content.

Productive and physiological responses of jambu (Acmella oleracea) under nutrient concentrations in nutrient solution

ABSTRACT In the last years, jambu has become popular and greatly appreciated, due to its remarkable taste. Thus, hydroponically cultivated jambu is promising, since it achieves better yield and production quality. The aim of this study was to evaluate the effect of ionic concentration in nutrient solution on growth, productivity and gas exchange of jambu. The experimental design was completely randomized, with five treatments and four replicates. The treatments consisted of variations of ionic concentration using the nutrient solution proposed by Hoagland & Arnon (25, 50, 75, 100 and 125%). The length of the main stem, stem diameter, number of inflorescence, leaf area, fresh and dry biomass (shoot, root and inflorescence), photosynthesis, stomatal conductance, transpiration, internal CO2 concentration, Ci/Ca ratio and instant carboxylation efficiency were evaluated. Ionic concentrations significantly affected the studied variables, except the stem diameter, the internal CO2 concentration and the Ci/Ca ratio. The number of inflorescences and the leaf area grew linearly with maximum values (37.8 units plant-1 and 1650.8 cm2 plant-1, respectively) obtained in ionic concentration of 125%. Maximum responses were observed for shoot fresh and dry mass (63.9 and 6.9 g plant-1), root fresh and dry mass (16.7 and 2.0 g plant-1) inflorescence fresh and dry mass (11.0 and 1.8 g plant-1), respectively, at ionic concentration of 125%. Liquid photosynthesis, stomatal conductance, transpiration and instant carboxylation efficiency achieved maximum responses of 17.9 µmol CO2 m-2 s-1, 0.3 mol H2O m-2 s-1, 6.3 mmol m-2 s-1 and 0.06 with estimated concentrations of 84, 70, 80 and 83% of ionic strength, respectively. Thus, we concluded that the ionic concentration of 125% is indicated to obtain a greater biomass accumulation.

Emergência e crescimento de plântulas de pimenta Cambuci em diferentes substratos

Cambuci pepper (Chapéu de Bispo), is a species of Brazilian origin, widespread in various regions of the country. Consumed mainly in natura and present in typical national cuisine, it is also used in industry and in the decoration of environments. The objective of the present work was to evaluate the germination and emergence of Cambuci pepper seedlings in three commercial substrates (Click Mudas®, Forth Condicionador Floreiras® e Top Garden Floreiras®). The substrates were placed in expanded polystyrene trays, followed by the sowing of pepper seeds, which were then kept in a greenhouse until the evaluations. The following were evaluated: germination percentage (PG), germination speed index (IVG), shoot length (CPA), root length (CR), fresh shoot mass (MFPA), fresh root mass (MFR), shoot dry mass (MSPA) and root dry mass (MSR). The results indicate that the most suitable substrate for germination and emergence of Cambuci pepper seedlings is Top Garden Floreiras®.

Evaluation of engineered soils for bioretention areas containing dredged Illinois River sand, compost, biosolids, and pyrolyzed biosolids

AbstractDredged Illinois River sand is nutrient poor and has low cation exchange capacity. Engineering this soil by adding amendments to increase nutrient retention may help sustain plant growth and absorb contaminants when the sand is used in bioslopes, bioswales, and rain gardens. The objectives of this study were to compare the physical and chemical properties of engineered soils derived from dredged Illinois River sand combined with mixtures of a locally produced compost, dried Class B biosolids from the Greater Peoria Sanitary District (GPSD), and pyrolyzed GPSD biosolids, and to study their effect on the growth of a grass mixture designed for chronically wet areas, such as bioslopes and/or bioswales along Illinois Department of Transportation (IDOT) highways. Dry and wet bulk densities of the soil mixtures increased with increasing levels of both biosolids and pyrolyzed biosolids. Soils containing higher levels of compost were linked to higher CEC, soluble salts, porosity, and soil moisture. Shoot and root lengths, and fresh and dry tissue mass were highest in mixtures containing the higher compost levels. These results indicate that the addition of compost to Illinois River sand may be required for adequate grass growth in these engineered soils saturated with water. The use of either biosolids or pyrolyzed biosolids as nutrient sources may need to be supplemented with compost for adequate plant growth.

AVALIAÇÃO DA PRODUÇÃO ORGÂNICA DE ALFACE AMERICANA (Lactuca sativa L.) EM FUNÇÃO DO MANEJO DO SOLO E ADUBAÇÃO COM RESÍDUOS DE ORIGEM ANIMAL E VEGETAL

O estudo teve o objetivo de avaliar a produção de alface americana Lucy Brown com adubação de resíduos de origem animal e vegetal. O delineamento experimental foi de blocos casualizados com quatro repetições. Os tratamentos foram: esterco bovino curtido, esterco bovino fresco, composto orgânico, brotos de leucena e testemunha. Avaliou-se massa fresca total, massa fresca comercial, massa fresca descarte, massa seca total, massa seca comercial, massa seca descarte, comprimentos de raízes, peso fresco total e peso seco total das raízes. Os adubos composto orgânico, esterco fresco, esterco curtido e leucena, quando não incorporados, reduziram a produção da massa fresca comercial. Os adubos não influenciaram na produção de massa fresca total, massa fresca descartável, massa seca total, massa seca comercial, massa seca descartável, no peso fresco e nem no peso total das raízes. Os adubos feitos em cobertura e os incorporados não diferiram na produção e comprimento das raízes das alfaces.

On-farm assessment of cassava root yield response to tillage, plant density, weed control and fertilizer application in southwestern Nigeria

Abstract Cassava is growing in importance in Nigeria as a food and industrial crop. Current yields are low due to poor soil fertility and because farmers do not use improved germplasm, clean planting material, or improved crop management in Nigeria. To provide feasible agronomic recommendations targeting increased root yield, the effects of tillage intensity, fertilizer application, plant density and weed control were tested in 230 farmers’ fields in southwestern Nigeria over two years. In 2016, tillage treatments were zero, single and double passage with a disc plough, followed by ridging (soil shaping) versus leaving the soil flat. Fertilizer application at 75:20:90 kg ha−1 NPK was tested against a control and two plant densities (10,000 versus 12,500 ha−1) were compared. In 2017, plant density at 10,000 ha−1 and double plough were excluded, while pre- and post-emergence herbicide application versus farmer’s choice of weed control (i.e. manual weeding using hand hoe) was introduced. Cassava was harvested at 12 months after planting, and yields were recorded as fresh root mass. In 2016, double plough (15.9 Mg ha−1) had a minor advantage over single plough (14.3 Mg ha−1), while zero plough produced 12.9 Mg ha−1 (P

GROWTH PROMOTION OF GENETICALLY IMPROVED Pinus taeda SEEDLINGS BY INOCULATION WITH SPECIES OF Bacillus.

This study was carried on evaluating effects of inoculation with Bacillus species and generations of genetically improved seeds on Pinus taeda growth in nursery conditions. Two experiments, based on distinct inoculation methods (sowing and post-emergence) were performed under a 3 x 2 factorial, completely randomized block design (3 levels of inoculation and 2 levels of genetic improvement of Pinus taeda). Plant height and diameter were measured at different stages along seedling development. At harvest, root volume, root fresh and dry mass, shoot fresh and dry mass and quality index were also estimated. Data were submitted to a two-way analysis of variance (p<0.05) and Tukey´s test was used to separate means (p<0.05). Data from experiment with inoculation at sowing showed that Bacillus amyloliquefaciens improved plant height (20%) and shoot dry mass (28%) of 2.0 generation seedlings compared to control plants. Regarding post-emergence inoculation, plants from 1.5 generation presented more pronounced effects of Bacillus amyloliquefaciens. Overall, inoculated seedlings were 9.8% taller and produced 60% more root dry mass than non-inoculated plants. Regardless of seedling generation, B. amyloliquefaciens increased Dickson Quality Index by 30%. These results suggest that each generation of genetically improved P. taeda has different growth responses to B. amyloliquefaciens. Methods of inoculation, combined with level of genetic improvement, must also be considered to obtain the best benefit to seedling development when using this rhizobacterium. Based on the current findings, inoculation with B. amyloliquefaciens should be incorporated as a silvicultural practice to improve growth of P. taeda under nursery conditions.

Effects of iron toxicity on germination and initial growth of Carica papaya L.

Iron (Fe) is vital for plant development. Its excessive is harmful, both to forest and cultivated species. This study analyzed the effect of high Fe doses on the germination and initial growth of Carica papaya seeds, submitted to concentrations of 0.045, 4, and 8 mM in the form of ferrous sulfate and FeEDTA. Germination percentage, germination speed index, shoot and root growth, fresh and dry mass of the seeds were analyzed. For the initial growth the following variables were analyzed: leaf area, stem and root growth, fresh and dry mass, quantification of chloroplastid pigments, analysis of chlorophyll a fluorescence, element contents and the activity of the enzymes Superoxide Dismutase, Catalase and Peroxidase. Fe stress affected the percentage and speed of germination, root growth, and the accumulation of biomass of C. papaya, with FeEDTA being responsible for the most pronounced effects. Fe led to increases in chlorophyll and photosynthetic performance without changes in carotenoid levels. The 8 mM treatments impaired root growth, aerial growth, leaf area expansion, and biomass accumulation. The increase in Fe concentration led to an increment in its deposition in root tissue, with a drop in potassium levels in the 8 mM treatment. There was an increase in Peroxidase activity when submitted to FeEDTA. There was no difference in Superoxide Dismutase and Catalase expression in any treatment. These results show the sensitivity of C. papaya species to toxic levels of Fe, which caused damage to metabolism and initial growth.

Atributos fisiológicos das sementes de soja submetidas ao resfriamento artificial

O presente trabalho teve como objetivo avaliar os atributos fisiológicos das sementes de soja submetidas ao resfriamento artificial previamente ao ensacamento. A pesquisa foi realizada no Laboratório de Sementes da Universidade Tecnológica Federal do Paraná - UTFPR, situada no município de Dois Vizinhos – Paraná. Foram utilizadas sementes das cultivares de soja TMG 7262 RR e TMG 7063 IPRO, produzidas na safra 2017/2018 e beneficiada na Unidade de Beneficiamento de Sementes da Cooperativa Agropecuária Tradição, na região de Pato Branco – Paraná. No momento do beneficamente os tratamentos foram separados, em amostras que passaram pelo resfriamento (Cool Seed), ou não resfriadas. Os testes para conferir a qualidade fisiológica das sementes de soja foram, germinação, envelhecimento acelerado, comprimento de parte área e raiz, massa seca e massa fresca, e condutividade elétrica. O experimento ocorreu em delineamento experimental inteiramente casualizado (DIC), com quatro repetições. Sendo que, o conjunto de dados foi submetido ao teste de normalidade e homogeneidade, e após, compridos os pressupostos, os dados foram submetidos à análise de variância (Anova). Havendo significância entre os tratamentos, com auxílio do programa estatístico Genes, utilizou-se o teste de teste de comparação de médias (Tukey a 5% de probabilidade). Desta forma, conclui-se que sementes de soja resfriadas artificialmente tem potencial fisiológico superior às sementes não resfriadas. No entanto, para lotes de sementes de alta qualidade fisiológica, este maior desempenho pode não ser observado.

Development and productivity of two beet genotypes for fertilization

Beet needs a high demand of nutrients to improve its development and productivity. The objective of this work was to evaluate the effect of fertilizer forms in the development and productivity of the beet crop. The experiment was carried out in the experimental area of the Fazenda Escola of the Higher Education Center of Campos Gerais, located in the city of Ponta Grossa-PR, between September and November 2018. The experimental design was randomized blocks in a 2x4 factorial scheme [2 genotypes of beet (Boron hybrid and Tall Top Early Wonder cultivar) x 4 forms of fertilization, T1 - control (without fertilization), T2 - poultry litter, T3 - bovine manure and T4 - NPK], containing four repetitions. The harvest was carried out at 75 days after transplanting the seedlings, harvesting five plants from each plot to carry out the analyzes, thus evaluating the number of leaves per plant, height of the aerial part, fresh mass of the aerial part and the root, productivity, horizontal diameter and commercial classification of root, presence of white rings through notes and soluble solids content (ºBrix). Among the different genotypes studied, the cultivar Tall Top Early Wonder was superior in the variables of plant height, fresh mass of roots and leaves and soluble solids, 75 days after transplantation. The cultivar Tall Top Early Wonder responded better, implying the idea that organic fertilization would be an alternative as a source of nutrients in beet production.

Chicken Manure: An Alternative in Increasing Production of Sweet Potato (Ipomoea batatas)

Chicken manure is accessible to family farmers, is produced in large volumes, and has a low cost. Therefore, it can be an alternative to increase the productivity of sweet potatoes (Ipomoea batatas), which is a culture of socioeconomic importance. The objective of the study was to evaluate the productivity of sweet potatoes under different doses of chicken manure, with and without liming, comparing to the use of chemical fertilizer NPK, in very clayey soil, from the perspective of economic efficiency. The experiment was conducted in the field from September 2019 to March 2020 in Manaus, Amazonas, Brazil. The experimental design was in randomized blocks with four replications, in a split-plot scheme 2 &amp;times; 5 + 1 (presence or absence of liming; five doses of chicken manure; and NPK, respectively. The evaluated parameters were: total and commercial productivity; number of total and commercial tuberous roots; harvest index; individual fresh mass, length, and diameter of tuberous roots. The effect of chicken manure was not influenced by the liming and there are no differences in agronomic values related to NPK. The dose of chicken manure that results in maximum production of the queen sweet potato variety is approximately 13 t ha-1, producing 25.2 t ha-1, while the resulting dose in maximum profit is approximately 12 t ha-1 with a production of the 25.1 t ha-1. The selling production directly to the final consumer increased profit by approximately 57.3%. Purchasing the input directly from the manufacturer reduced costs by approximately 74.5%. The use of chicken manure has a greater economic advantage compared to NPK in very clayey soil.

Growth and yield of carrot inoculated with Bacillus subtilis and Pseudomonas fluorescens

The objective of this study was to evaluate the effects of inoculation and co-inoculation with Bacillus subtilis and Pseudomonas fluorescens on carrots with reduced nitrogen use. A field experiment was carried on, with five treatments and five replicates, evaluating the growth and yield responses of inoculated carrots. Responses were observed in height only two weeks before harvesting, and the number of leaves was most affected from the beginning to the middle of the cultivation cycle. Although the fresh shoot mass was negatively affected by the inoculation treatments, the dry shoot mass did not respond to the rhizobacteria. The length of roots inoculated with P. fluorescens or co-inoculated with both bacteria increased from 21 cm, without inoculation, to 25 cm. The root volume and dry mass values were the same across the treatments. However, the fresh root mass was improved by between 70 and 81.8% with P. fluorescens and co-inoculation, respectively. More positive responses to inoculation were observed with reduced nitrogen levels, suggesting a potential in the rhizobacteria strains for use in reduced-input agricultural practices. Moreover, based on the findings, Pseudomonas fluorescens can be recommended as a plant growth-promoting microorganism in carrot cultivation.

Growth and production of basil under different luminosity and water replacement levels

ABSTRACT Basil is used as spice and for medicinal purposes. Its growth is influenced by environmental factors, mainly soil moisture and air temperature. Thus, this study was installed to evaluate growth and production of basil under different levels of luminosity and water replacement. The experimental design was completely randomized, with six replicates, arranged in split plot scheme, with three luminosity levels in the plots (full sun, 50% and 70% shading) and four water replacement levels in the subplots (25, 50, 75 and 100% ETc). We evaluated plant height, stalk diameter, number of leaves and branches, root system volume, the largest root length, fresh and dry mass of roots and leaves. Data were submitted to variance analysis to observe significant differences between treatments and interactions. Luminosity effects were evaluated using Tukey test (p≤0.05%) and the effects of water regime, with the aid of regression analysis. According to data, 50% shading and 100% water replacement, lost through crop evapotranspiration, resulted in higher values of plant height, stalk diameter, branch growth, fresh and dry mass of leaves, and number of leaves. Full sun environment and 100% water replacement provided an increase in root dry mass and volume.

Avaliação de teor de metais pesados em cultivo de jambu (Acmella oleracea [(L) R. K Jasen]) com sedimento de viveiro de Tambaqui (Colossoma macropomum

A aquicultura tem se destacado nos últimos anos como fonte de proteína animal, porém, um de seus entraves é o descarte indevido de seus efluentes, que além de possuir resíduos orgânicos, apresenta nutrientes essenciais. O reaproveitamento desses rejeitos na agricultura pode ser uma provável saída para sanar tal problema, gerando aporte nutritivo para plantas e mitigando contaminações ao meio ambiente. O estudo objetivou avaliar a viabilidade do uso de sedimento de viveiro de produção de tambaqui para o cultivo de jambu na Região Amazônica. O experimento foi conduzido em casa de vegetação na Universidade Federal Rural da Amazônia utilizando resíduo oriundo de tanques de piscicultura. Foi constituído de cinco tratamentos, variando as concentrações de Terra preta (TP) e Sedimento de viveiro de piscicultura (SP), e acondicionado com 1kg Casca de arroz queimado (CA) para cada concentração. As concentrações foram compostas por Tratamento 1 (100% TP), Tratamento 2 (75% TP + 25% SP), Tratamento 3 (50% TP + 50 % SP), Tratamento 4 (25% TP + 75% SP) e Tratamento 5 (100% SP). O sedimento foi coletado em um viveiro de produção semi-intensivo de tambaqui e as plantas de Jambu foram irrigadas diariamente em vasos de polietileno até 79 dias após germinadas para a realização da colheita. O delineamento experimental foi inteiramente casualizado com 5 tratamentos e 10 repetições, sendo uma planta por repetição ao final do cultivo. Foram obtidos dados de Altura (ALT), Diâmetro de coleto (D), Número de folhas (NF), Clorofila (C), Área foliar (AF), Massa fresca total (MFT), Massa fresca de folha (MFF), Massa fresca de caule (MFC), Massa fresca de flor (MFFL), Massa fresca de raiz (MFR), Massa seca total (MST), Massa seca de folha (MSF), Massa seca de caule (MSC), Massa seca de flor (MSFL) e Massa seca de raiz (MSR). Os dados foram submetidos à análise de variância, sendo as equações escolhidas com base na significância dos coeficientes de regressão, a 5% de probabilidade, utilizando o software Sisvar, versão 5.6. Os tratamentos 2 (75% TP + 25% SP) e 4 (25% TP + 75% SP) foram os que apresentaram os maiores valores para a maioria dos fatores analisados. Quando analisado o comportamento linear da regressão, foi encontrado correlação positiva com as concentrações de sedimento para ALT, NF, AF, MFFL e MSFL, e os demais parâmetros apresentaram comportamento quadrático, tendo faixa ótima sempre próxima aos tratamentos 3 (50% TP + 50 % SP) e 4 (25% TP + 75% SP). A produção do jambu com resíduos de cultivo de peixe é viável haja vista o maior incremento de biomassa nas plantas submetidas a este tipo de substrato.

Initial development of watermelon in fuction of substrates and irrigation with saline water

We evaluated the initial development of watermelon cv. Crimson Sweet seedlings grown in different organic substrates and electrical conductivity of irrigation water. The experiment was carried out in a greenhouse between January and March of 2017. The experimental design was in randomized blocks with factorial arrangement 3 x 5. The treatments were combinations of three substrates: soil + bovine manure (SBM) (1:1); soil + sheep manure (SSM) (1:1) and commercial substrate Basaplant® (CS), and five electrical conductivity of irrigation water (ECiw): C1 – 0.3 dS m-1; C2 – 1.5 dS m-1; C3 – 2.7 dS m-1; C4 – 3.9 dS m-1 and C5 – 5.1 dS m-1. Plant height, number of leaves, stem diameter, root fresh mass, stem fresh mass, leaf fresh mass, root dry mass, stem dry mass, and leaf dry mass were evaluated at 37 days after sowing (DAS). The interaction between substrate x ECiw significantly affected the variables plant height, number of leaves, stem fresh mass and leaf fresh mass; all the analyzed variables were affected by substrate factor, while plant height, number of leaves, root dry mass, stem dry mass, and leaf dry mass were affected by ECiw. It is possible to produce watermelon cv. Crimson Sweet seedlings using water with electrical conductivity up to 2.86 dS m-1 associated with commercial substrate and up to 2.67 dS m-1 associated with sheep manure. It can be inferred that the use of commercial substrate is more suitable for the production of watermelon cv. Crimson Sweet seedlings.

Millicomposting: composting based on the use of diplopods aiming at the production of organic substrates

Millicomposting, a not so well-known biotechnology, involves the biotransformation of vegetable residues into stable organic matter, promoted by the activity of diplopods, popularly known as millipedes. Considering the importance of the substrate in the production of vegetable seedlings, the aim of the present work was to assess the millicomposting technique and evaluate the efficiency of millicompost in the production of seedlings of the American lettuce cultivar Angelina. The millicompost consisted of Bauhinia sp. (cow’s foot leaves), Paspalum notatum (grass clippings), Musa sp. (banana leaves), and cardboard. Physical, physicochemical, and chemical analyses of the obtained millicompost were performed 180 days into the experiment. The lettuce seedlings were grown in expanded polystyrene trays of 200 cells and the evaluations occurred 30 days after sowing. The evaluated phytotechnical characteristics were fresh and dry shoot mass, fresh and dry root mass, plant height, number of leaves, seedling vigor, and clod stability. The millicompost had a higher total nutrient content and lower volume density than the Biomix® organic substrate. All of the developmental parameters of the lettuce seedlings differed between the millicompost and the Biomix® organic substrate; all of the mean values were higher for the millicompost, except for the number of leaves, which did not differ from the Biomix® organic substrate. The millicomposting process facilitated the reuse of organic waste by converting it into quality organic compost and resulted in the efficient production of excellent quality lettuce seedlings.