scholarly journals SUBSTRATE, LIME, PHOSPHORUS AND TOPDRESS FERTILIZATION IN MACAW PALM SEEDLING PRODUCTION

2016 ◽  
Vol 40 (2) ◽  
pp. 235-244 ◽  
Author(s):  
Leonardo Duarte Pimentel ◽  
Claudio Horst Bruckner ◽  
Candida Elisa Manfio ◽  
Sérgio Yoshimitsu Motoike ◽  
Hermínia Emília Prieto Martinez

ABSTRACT The macaw palm [Acrocomia aculeata (Jacq.) Lood. ex Mart] has been domesticated to subsidize biodiesel production programs in Brazil. However, little is known about the seedling production of this species. This study aimed to evaluate substrate mixtures, limestone and phosphorus rates for substrate amendment and topdressing frequency in macaw palm seedlings. Three trials were conducted in a greenhouse up to six months of nursery cultivation. Trial 1: determination of percent mineral and organic fractions of seven substrate mixtures. Trial 2: evaluation of four limerates for soil amendment versus four phosphorus rates. Trial 3: evaluation of N, K and Mg topdressing frequency. Significant differences were found in the three trials for most of the variables (plant height, leaf number, shoot dry mass, root dry mass, vigor and bulb diameter). The main results obtained were as follow: Trial1 - the best seedling growth was observed in substrates with at least 25% organic matter. Trial2 -lime rates ranging from 0.50 to 1.25 kg associated with 3 to 4 kg of single superphosphate per m3 of substrate provided the best seedling growth. Trial 3 - topdressing fertilization provided better development of seedlings regardless of frequency.

Agronomy ◽  
2021 ◽  
Vol 11 (5) ◽  
pp. 851
Author(s):  
Sonia Cacini ◽  
Sara Di Lonardo ◽  
Simone Orsenigo ◽  
Daniele Massa

Professional peat-free substrates for ornamental plant production are increasingly required by nursery growers. Most promising materials are green compost, coconut coir dust, and woody fibre, used alone or in mixtures. One of the major concerns is pH, usually higher than optimal. In this work, a method based on a three-step procedure was adopted to acidify three organic matrices alone or in mixtures and to individuate the most suitable product, between iron(II) sulphate 7-hydrate and elemental sulphur chips. Firstly, the determination of the buffering capacity by dilution with sulphuric acid was carried out to determine dosages. Afterwards, an incubation trial of 84 (iron(II) sulphate) or 120 days (sulphur chips) was conducted on matrices and substrate mixtures with calculated doses in a climatic chamber maintained at 21 °C. Iron(II) sulphate resulted not suitable because it caused a rapid, but not lasting, pH lowering and an excessive electrical conductivity (EC) increase. Sulphur chips could instead guarantee an adequate and lasting pH lowering. These results were then validated in the open field trial on matrices and substrates. The proposed acidification methodology could be considered in developing new substrates, but the rapidity of pH acidification and EC increase on plant and mineral nutrition should be further investigated.


2016 ◽  
Vol 20 (1) ◽  
pp. 13-22
Author(s):  
Beata Brzychczyk ◽  
Zbigniew Kowalczyk ◽  
Jan Giełżecki

AbstractThe objective of the paper was to analyse the use of the designed photobioreactor for freshwater microalgae cultivation in the controlled laboratory conditions. The work covered the design and construction of photobioreactors (PBR) and setting up comparative cultivations of freshwater microalgae chlorelli vulgaris along with determination of the biomass growth intensity for a varied amount of supplied culture medium. It was found out that the constructed PBR may be used for microalgae cultivation in the controlled conditions. The impact of the culture medium amount on the growth of chlorelli vulgaris was proved. As a result of the increase of culture medium concentration to 30.1-120.4 ml·l−1 of water, dry mass in photobioreactorsincreased respectively from 1.33 g·dm−3 to 4.68 g·dm−3.


2009 ◽  
Vol 71 (S208) ◽  
pp. 33c-39c
Author(s):  
Enping Chen ◽  
Jang-Hyun Chung ◽  
Per G. Söderberg ◽  
Bo Lindström
Keyword(s):  

2020 ◽  
Vol 98 (Supplement_2) ◽  
pp. 34-34
Author(s):  
Maegan A Reeves ◽  
Courtney E Charlton ◽  
Shannon R Wilkerson ◽  
John G Rehm ◽  
Terry D Brandebourg

Abstract Mangalica pigs are a popular niche breed given their reputation for superior quality pork. However, growth and carcass parameters for this breed are poorly documented. Our objective was to better characterize optimal harvest weights for the Mangalica breed. To accomplish this, a growth trial was conducted whereby pigs (n=56) were randomly distributed across stratified harvest weights (50, 57, 68, 82, 93, 102, 127 kg) in a completely randomized design. Pigs were fed standard finisher rations with individual daily feed intakes and weekly body weights recorded for all animals. At 24h postmortem, carcasses were split and ribbed with marbling and loin eye area (LEA) measured at the 10th rib. Primal cuts were fabricated and individually weighed. Fat back was separated from the loin and weighed. As expected, live weight significantly increased across weight class (P < 0.0001). ADG was similar across classes up to 82 kg live weight before steadily declining with increasing weight class (P < 0.0025). Likewise, feed efficiency did not differ between classes until weights heavier than 82 kg (P < 0.03). LEA significantly increased by class up to 82 kg and then plateaued as harvest weight increased further (P < 0.003). Marbling score significantly increased with increasing weight class up to 102 kg where they then plateaued (p < 0.04). Fat back dramatically increased across all weight classes (p < 0.0001) despite negligible increases in LEA or marbling after 102 kg. Primal cut weights for the ham (P < 0.0001), loin (P < 0.0001), Boston butt (P < 0.0001), shoulder (P < 0.0001), and belly (P < 0.0001) all significantly increased with increasing live weight. These data suggest an optimal harvest weight occurs between 82 to 102 kg while offering little objective justification for the current practice of harvesting Mangalica pigs at much heavier live weights.


2019 ◽  
pp. 1258-1266 ◽  
Author(s):  
Thiago Henrique Ferreira Matos Castañon ◽  
Boanerges Freire de Aquino ◽  
Edna Maria Bonfim Silva ◽  
Izabel Maria Almeida Lima ◽  
Ana Paula Alves Barreto Damasceno

The objective of this study was to analyze the effect of soil fertilization with sulfur-based fertilizers, sulfate and elemental sulfur forms on biomass production, nutrient characteristics of sorghum and soil chemical properties. The experiment was carried out in a 4 x 4 factorial scheme (four sulfur sources: single superphosphate, agricultural gypsum, elemental sulfur powder and elemental sulfur granulated with bentonite, and four sulfur doses: 0, 40, 80, 120 mgdm-3) using four replications in a completely randomized design, being cultivated in pots under greenhouse conditions. The sorghum was cultivated for a period of 51 days after emergence of the seedlings. The shoot dry mass, shoot macronutrients content, root and soil and pH of the soil were evaluated. There were interactions between sources and sulfur doses in the variables such as shoot dry mass, sulfur in the root, sulfur and calcium in the soil. Elemental sulfur (granulate) showed lower concentrations of phosphorus, sulfur and N:S ratio in the shoot. The concentrations of potassium, calcium and magnesium did not show significant differences, both for the shoot and the root. The pH of the soil was reduced depending on the sources and doses of elemental sulfur. The sources and doses of sulfur did not influence the levels of phosphorus, potassium, and magnesium in the soil. The elemental sulfur in the form of powder is the best source of sulfur for forage sorghum cultivated in soil with alkaline pH.


Bragantia ◽  
2011 ◽  
Vol 70 (1) ◽  
pp. 40-45 ◽  
Author(s):  
Leonardo Bianco de Carvalho ◽  
Pedro Luis da Costa Aguiar Alves ◽  
José Valcir Fidelis Martins

Determination of competitive relationships among plant species requires appropriate experimental designs and method of analysis. The hypothesis of this research was that two species growing in coexistence show different growth and development due to their relative competitiveness. This research aims to measure the relative competitiveness of wheat crop compared to Alexandergrass by the interpretation of plant density and proportional effects using replacement series experiments. Monocultures were cultivated in densities of 1, 3, 5, 10 and 15 plants per pot and analyzed by regression of dry mass data. Mixture experiment was cultivated in wheat:Alexandergrass proportions of 0:6, 1:5, 2:4, 3:3, 4:2, 5:1 and 6:0 plants per pot and analyzed by graphical interpretation of growth and production characteristics. Both experiments were carried out in randomized complete block design with four replicates. Alexandergrass was more sensitive to intraspecific competition than wheat. Alexandergrass was lightly more competitive than wheat. Number and weight of spikes and number of tillers were the wheat characteristics more affected by Alexandergrass interference.


Author(s):  
Vanderlise Giongo ◽  
Alessandra M. Salviano ◽  
Betina R. C. dos Santos ◽  
Emylly F. Leal

Phosphorus (P) plays an important role in the growth of root system as well as the tillering grass, being fundamental to increase the productivity of these species. The aim of this study was to evaluate the development of buffel grass cultivars and establish critical values of P in plant and soil. The experimental set up was a 4 x 5 factorial scheme (four Cenchrus ciliaris cvs.: Biloela, Aridus, CPATSA 7754 and Pusa Giant, and five doses of P2O5 - 0, 30, 60, 90 and 120 kg ha-1) with four replications. After 90 days of cultivation, dry mass of shoot (DMS) and root (DMR) production and the P accumulation (Pacc) were determined. Soil samples to determine the P content and determination of the critical level (CriLev) were also collected. The cv. Biloela presented lower DMR and DMS production compared to the other cultivars. The cultivares Biloela, Pusa Giant and Aridus showed different critical levels of P in soil and plant, obtained in the greenhouse showing that they have different requirement of this nutrient for their growth. The cultivar CPATSA 7754 showed higher phosphorus requirement and did not permit to establish critical levels with doses used in the present study.


2016 ◽  
Vol 22 (4) ◽  
pp. 431-443
Author(s):  
Xiaochan Zhu ◽  
Hui Liu ◽  
Dejan Skala

In this study, mixed system containing manganese carbonate (MnCO3) and zinc glycerolate (ZnGly) was synthesized, and tested as solid catalyst for transesterification of soybean oil and biodiesel production. The samples of MnCO3/ZnGly before and after usage for transesterification process were characterized using different techniques: determination of basic strength, determination of specific surface area according to Brunauer-Emmett-Teller (BET), measuring the mass change using thermal gravimetric analysis (TGA), investigating the solid phase content and presence of different specific elements and groups by X-Ray diffraction (XRD), the Fourier transform infrared (FT-IR) spectroscopy, the scanning electron microscopy (SEM) with energy dispersive spectroscopy (EDS). The effects of different working parameters of transesterification were also investigated: temperature (438-458K), duration of transesterification (0-3.5h), methanol to oil molar ratio (12:1-36:1) and used amounts of catalyst (1-5 mass%). The reusability and stability of MnCO3/ZnGly were analyzed and obtained results showed that MnCO3/ZnGly exhibited a good activity with 100% TG conversion and 81.5% FAME yield with fresh catalyst, and can give 95-100% TG conversion and 62-78% FAME yield after 13 repeated use of same amount of catalyst without regeneration processes. Content of Mn and Zn in biodiesel and glycerol was analyzed by ICP-AAS after each reuse of catalyst.


2018 ◽  
Vol 54 (10) ◽  
pp. 3071-3080 ◽  
Author(s):  
Małgorzata Kowalska ◽  
Sławomir Janas ◽  
Magdalena Woźniak

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