scholarly journals Effects of different light levels on the initial growth and photosynthesis of Croton urucurana Baill. in southeastern Brazil

2003 ◽  
Vol 27 (1) ◽  
pp. 53-57 ◽  
Author(s):  
Amauri Alves de Alvarenga ◽  
Evaristo Mauro de Castro ◽  
Érico de Castro Lima Junior ◽  
Marcelo Murad Magalhães
Keyword(s):  
Solar Radiation ◽  
Photosynthetic Rate ◽  
Chlorophyll Concentration ◽  
Dry Weight ◽  
Southeastern Brazil ◽  
Experimental Unit ◽  
Initial Growth ◽  
Higher Plant ◽  
Full Sunlight ◽  
Four Levels

Four levels of shading (full sunlight (0%), 30, 50, 70% of solar radiation interception on growth, chlorophyll concentration and photosynthetic rate were studied in Croton urucurana Baill., a pioneer plant species. This species seedlings are of potential interest for reforestation projects and recovery of degraded areas. The seedlings were grown in pots containing soil and sand (2:1) and later transferred to plastic bags of 3 dm³ and submitted to different levels of shading (30, 50, 70%) of solar radiation and full sunlight, as control. The experimental design was completely randomized with five replicates and each experimental unit was composed of five plants. The results suggest that plants submitted to 70% shading showed higher dry weight accumulation in leaf and root, and higher plant height and leaf area. However, the seedlings root system showed higher dry biomass under full sunlight. It was observed a tendency to increase chlorophyll concentration and to decrease photosynthetic rate with the increase of the shading level.

scholarly journals INITIAL GROWTH OF Dipteryx alata PLANTS UNDER WATER DEFICIT

2018 ◽  
Vol 42 (1) ◽  
Author(s):  
Fabio Santos Matos ◽  
Igor Alberto Silvestre Freitas ◽  
Lidiane Villas Boas Dos Santos ◽  
Daniel Guimarães Venâncio ◽  
Patrícia Souza da Silveira
Keyword(s):  
Water Deficit ◽  
Chlorophyll Concentration ◽  
Experimental Unit ◽  
Water Deficit Stress ◽  
Total Biomass ◽  
Initial Growth ◽  
Total Carotenoids ◽  
Randomized Design ◽  
Water Volumes ◽  
Dipteryx Alata

ABSTRACT The objective of this study was to analyze the effect of water deficit stress on the growth of Dipteryx alata plants. The experiment was carried out on a bench in full sun at the Goiás State University experimental unit, in Ipameri town, Goiás. Dipteryx alata seeds were collected from native plants in that municipality and sown in four-liter pots containing a mixture of soil, sand and cattle manure at ratio 3:1:0.5, respectively. The experiment was set up following the completely randomized design with five treatments (plants irrigated for 25 days with water volumes corresponding to 0%, 25%, 50%, 75%, and 100% of daily evapotranspiration) and six replicates. Treatments were applied when the plants were 60 days old, and at 85 days the plants were assessed for the following parameters: plant height, stem diameter, number of leaves, foliar chlorophyll concentration (a+b ), total carotenoids, relative water content, transpiration, leaf, stem and root mass ratios, and total biomass. During early development, the Dipteryx alata plants were highly sensitive to water deficit, significantly slowing down vegetative growth. Accordingly, in order to remain alive, the plants drastically reduced transpiration as a result of high stomatal sensitivity.

scholarly journals Photosynthetic Rate, Flowering, and Yield Component Alteration in Hazelnut in Response to Different Light Environments

1996 ◽  
Vol 121 (6) ◽  
pp. 1103-1111 ◽  
Author(s):  
Cheryl R. Hampson ◽  
Anita N. Azarenko ◽  
John R. Potter
Keyword(s):  
Photosynthetic Rate ◽  
Dark Respiration ◽  
Stomatal Density ◽  
Chlorophyll Concentration ◽  
Light Response ◽  
Dry Weight ◽  
Yield Component ◽  
Response Curves ◽  
Photosynthetic Rates ◽  
Light Response Curves

In hazelnut (Corylus avellana L.), vigorous vegetative growth and traditional orchard practices that include little or no pruning combine to produce a dense, shady canopy. A study designed to quantify the effect of shade on reproduction and photosynthetic rate in this shade-tolerant species was undertaken to assess whether some degree of pruning might improve productivity. Shade cloth was used to exclude 30%, 47%, 63%, 73%, or 92% of ambient sunlight from whole `Ennis' and `Barcelona' trees from mid-May until harvest. Photosynthetic light response curves were obtained for leaves that had developed in full sunlight, deep inside the canopy of unshaded trees, or in 92% shade. Light-saturated net photosynthetic rates were 12.0, 6.1, and 9.3 μmol·m-2·s-1 of CO2 and dark respiration rates were 2.0, 1.1, and 0.7 μmol·m-2·s-1 of CO2, respectively, for the three light regimes. Light-saturated photosynthetic rates of leaves from 30% or 63% shade differed little from the control (0% shade). Area per leaf increased by 49% and chlorophyll concentration (dry weight basis) by 157% as shading increased from 0% to 92%. Shading to 92% reduced specific leaf weight (68%), stomatal density (30%), light compensation point (69%), and dark respiration rate (63%) compared to controls. Female inflorescence density declined by about one-third and male inflorescence density by 64% to 74% in the most heavily shaded trees of both cultivars compared to controls. Shade was more detrimental to yield than flowering: yield per tree dropped by >80%, from 2.9 to 3.4 kg in full sun to 0.6 to 0.9 kg in 92% shade. Shade reduced yield primarily by decreasing nut number and secondarily by decreasing nut size. The incidence of several kernel defects increased as shade increased. Therefore, hazelnut leaves showed considerable capacity to adapt structurally and functionally to shade, but improving light penetration into the canopy would probably increase orchard productivity.

scholarly journals Light Intensity Affects Growth, Photosynthetic Capability, and Total Flavonoid Accumulation of Anoectochilus Plants

HortScience ◽  
2010 ◽  
Vol 45 (6) ◽  
pp. 863-867 ◽  
Author(s):  
Zengqiang Ma ◽  
Shishang Li ◽  
Meijun Zhang ◽  
Shihao Jiang ◽  
Yulan Xiao
Keyword(s):  
Light Intensity ◽  
Chlorophyll Concentration ◽  
Dry Weight ◽  
Total Flavonoid ◽  
Stem Length ◽  
Photon Flux ◽  
Low Light ◽  
Four Levels ◽  
Anoectochilus Formosanus ◽  
Flavonoid Accumulation

Anoectochilus formosanus, a medicinal plant used to treat hypertension, lung disease, and liver disease, was grown to maximize biomass and secondary metabolite production in a controlled environment under four levels of photosynthetic photon flux (PPF), namely, 10, 30, 60, or 90 μmol·m−2·s−1, that is L10, L30, L60, and L90 treatments, respectively. On Day 45, all growth values were greatest for the L30 plants. Dry weight was lowest for the L10 plants. Leaf area, stem length, and fresh weight were lowest for the L90 plants. The chlorophyll concentration was highest in the L10 treatment and decreased with increasing PPF. Electron transport ratios of leaves were highest in the L30 treatment and lowest in the L90 for the second leaf (counted down from the apex) and in the L10 for the third leaf. An increase in light intensity from 10 to 60 μmol·m−2·s−1 increased the superoxide dismutase activity and was associated with an increase in the total flavonoid concentration. The total flavonoid concentration (mg·g−1 DW) was greatest in the L60 and lowest in the L90. However, the total flavonoid content (mg/plant) was highest in the L30 plants as a result of great biomass. The results indicated that A. formosanus is a typical shade plant suitable to grow under low light intensity at PPF of 30 to 50 μmol·m−2·s−1 for both growth and production of total flavonoid. A light intensity of 90 μmol·m−2·s−1 induced stress on plant growth and reduced photosynthetic capability and the flavonoid accumulation.

scholarly journals Crescimento inicial de Erythrina velutina em diferentes substratos com adubação orgânica

2016 ◽  
Vol 11 (5) ◽  
pp. 30
Author(s):  
Mychelle Karla Teixeira de Oliveira ◽  
Jeferson Luiz Dallabona Dombroski ◽  
Rita De Cássia Araújo de Medeiros ◽  
Valmor Elias Tomczak ◽  
Raul Martins de Farias
Keyword(s):  
Growth Rate ◽  
Leaf Area ◽  
Folk Medicine ◽  
Weight Ratio ◽  
Dry Weight ◽  
Cattle Manure ◽  
Experimental Unit ◽  
Initial Growth ◽  
Organic Fertilization ◽  
Basal Diameter

<p><em>Erythrina velutina </em>é uma espécie arbórea nativa do Nordeste Brasileiro, empregada no paisagismo, na regeneração de áreas degradadas e na medicina popular. Objetivou-se com este trabalho avaliar o crescimento de mudas de <em>Erythrina velutina</em> produzidas em substratos com adubação orgânica. O experimento foi conduzido em delineamento inteiramente casualizado, com parcelas subdivididas no tempo, com cinco repetições, sendo a unidade experimental representada por 20 mudas. O primeiro fator foi constituído por dois substratos (solo de Mossoró-RN + esterco bovino (4:1) e solo de Angicos-RN + esterco bovino (4:1)), e o segundo fator constituído de dois acessos. Ao longo do experimento foram realizadas coletas, para avaliação de crescimento (28, 56, 84, 112 e 140 dias após a semeadura), com intervalos de 28 dias. Em cada coleta, as mudas foram analisadas quanto ao comprimento da parte aérea, ao número de folhas, ao diâmetro de coleto, à área foliar, à massa da matéria seca (caule, folhas, raiz, parte aérea, relação da parte aérea e raiz, e total). Pode-se concluir que os acessos de <em>Erythrina</em> <em>velutina</em> tiveram crescimento rápido e uniforme quando produzidas nos dois substratos (solo de Mossoró-RN + esterco bovino curtido (4:1) e solo de Angicos-RN + esterco bovino curtido (4:1)).</p><p align="center"><strong><em>Initial growth of Erythrina velutina in different substrates with organic fertilization </em></strong></p><p><strong>Abstract</strong><strong>: </strong><em>Erythrina velutina</em> is a tree native to the Brazilian northeast, used in landscaping, regeneration of degraded areas and in folk medicine. The objective of this work was to obtain information on <em>Erythrina velutina</em> of two accessions conducted in substrates with organic fertilization. The experiment was conducted in a completely randomized design with split plot with five replications and the experimental unit was represented by 20 seedlings. The first factor was composed of two substrates (sand + cattle manure (4:1) and soil + cattle manure (4:1)) and the second factor consisted of two accessions. Throughout the experiment were five collections of plants for evaluation of growth (28, 56, 84, 112 and 140 days after sowing), with intervals of 28 days. At each sampling date, the following characteristics were analyzed: shoot length, leaf number, basal diameter, leaf area, dry matter (aerial part, branches, leaves, roots, shoots, shoot to root dry weight ratio), leaf area ratio, leaf weight ratio, specific leaf area, absolute growth rate, relative growth rate and net assimilation rate. It can be concluded that accessions of <em>Erythrina velutina</em> grew fast and even when produced in the two substrates consisting of sand and / or soil with added manure.</p><br /><strong></strong>

scholarly journals Water Use Efficiency in Popcorn (Zea mays L. var. everta): Which Physiological Traits Would Be Useful for Breeding?

Plants ◽  
2021 ◽  
Vol 10 (7) ◽  
pp. 1450
Author(s):  
Jhean Torres Leite ◽  
Antonio Teixeira do Amaral Junior ◽  
Samuel Henrique Kamphorst ◽  
Valter Jário de Lima ◽  
Divino Rosa dos Santos Junior ◽  
...  
Keyword(s):  
Water Use Efficiency ◽  
Water Use ◽  
Chlorophyll Concentration ◽  
Dry Weight ◽  
Co2 Assimilation ◽  
Inbred Lines ◽  
Experimental Unit ◽  
Root Angle ◽  
Net Co2 Assimilation ◽  
Use Efficiency

To ensure genetic gains in popcorn breeding programs carried out under drought conditions knowledge about the response of morphophysiological traits of plants to water stress for the selection of key traits is required. Therefore, the objective was to evaluate popcorn inbred lines with agronomically efficient (P2 and P3) and inefficient (L61 and L63) water use and two hybrids (P2xL61 and P3xL63) derived from these contrasting parents, cultivated under two water regimes (WW watered—WW; and water-stressed—WS) in a greenhouse, replicated five times, where each experimental unit consisted of one plant in a PVC tube. Irrigation was applied until stage V6 and suspended thereafter. Individual and combined analyses of variance were performed and the genotypic correlations and relative heteroses estimated. The water use efficient inbred lines were superior in root length (RL), root dry weight (RDW), and net CO2 assimilation rate (A), which were the characteristics that differentiated the studied genotypes most clearly. High heterosis estimates were observed for RL, SDW, leaf width (LW), leaf midrib length (LL), and agronomic water use efficiency (AWUE). The existence of a synergistic association between root angle and length for the characteristics A, stomatal conductance (gs), and chlorophyll concentration (SPAD index) proved most important for the identification and phenotyping of superior genotypes. Based on the study of these characteristics, the higher AWUE of the previously selected inbred lines could be explained. The results reinforced the importance of root physiological and morphological traits to explain AWUE and the possibility of advances by exploiting heterosis, given the morphophysiological superiority of hybrids in relation to parents.

scholarly journals Growth, Photosynthesis, and Physiological Responses of Ornamental Plants to Complementation with Monochromic or Mixed Red-Blue LEDs for Use in Indoor Environments

Agronomy ◽  
2020 ◽  
Vol 10 (2) ◽  
pp. 284
Author(s):  
Pedro García-Caparrós ◽  
Gabriela Martínez-Ramírez ◽  
Eva María Almansa ◽  
Francisco Javier Barbero ◽  
Rosa María Chica ◽  
...  
Keyword(s):  
Photosynthetic Rate ◽  
Soluble Sugar ◽  
Chlorophyll Concentration ◽  
Soluble Sugars ◽  
Dry Weight ◽  
Physiological Parameters ◽  
Specific Response ◽  
Physiological Level ◽  
Total Dry Weight ◽  
Red Leds

Inch (Tradescantia zebrina) and spider (Chlorophytum comosum) plants were grown in a growth chamber for two months in plastic containers to evaluate the effects of different light treatments (TO Tube luminescent Dunn (TLD) lamps or control), TB (TLD lamps + blue light emitting diodes (LEDs)), TR (TLD lamps + red LEDs), and TBR (TLD lamps + blue and red LEDs) on biomass, photosynthesis, and physiological parameters. Total dry weight and water content were evaluated at the end of the experimental period. After two months, pigment concentrations and the photosynthetic rate were assessed in both species. The total soluble sugar, starch, and proline concentrations in the leaf as physiological parameters were studied at the end of the experiment. Both species had increased root, shoot, and total dry weight under blue LEDs conditions. The chlorophyll concentration showed a specific response in each species under monochromic or mixed red-blue LEDs. The highest photosynthetic rate was measured under the addition of mixed red-blue LEDs with TLD lamps. At the physiological level, each species triggered different responses with respect to total soluble sugars and the proline concentration in leaves under monochromic or mixed red-blue LEDs. Our study demonstrated that the addition of blue LEDs is advisable for the production of these ornamental foliage species.

scholarly journals RESPONSE OF VEGETATIVE GROWTH FOR THE TREATMENT OF ORGANIC NUTRIENT AND CALCIUM CHLORIDE FOR GERBERA PLANT Gerbera jamesonii

2017 ◽  
Vol 48 (1) ◽  
Author(s):  
Jawad & Majeed
Keyword(s):  
Humic Acid ◽  
Calcium Chloride ◽  
Calcium Content ◽  
Dry Weight ◽  
Leaf Nitrogen ◽  
Experimental Unit ◽  
Leaf Nitrogen Content ◽  
College Of Agriculture ◽  
Two Factors ◽  
Four Levels

This study was conducted in the lath house, Horticultural Department, College of Agriculture – University of Baghdad- Jadriya during the spring and autumn seasons 2015 to investigate the influence of humic acid spray and calcium chloride spray on f “Yanara” gerbera cultivar.  This study included two factors; humic acid spray (H) and calcium chloride spray (Ca). The first factor four levels were used, 0, (H0), 5 (H5), 7.5 (H7.5) and 10 (H10) ml.L-1 and four levels of calcium chloride, 0 (Ca0), 50 (Ca50), 100 (Ca100) and 150 (Ca150) mg.L-1. Each treatment replicated three times with a factorial experiment using RCBD. Five plants in experimental unit and the number of plants used was 240 trees. The experimental results showed that humic acid at 10 ml.L-1 and calcium chloride at 150 mg.L-1 (Ca150H0) significantly gave the highest leaves number of 11.20 and 11.47 leaves, the highest leaf area of 195.21 and 210.25 cm2, the highest plant dry weight of 16.92 and 17.95gm, the highest leaf nitrogen content of 2.50 and 2.45 %, highest leaf phosphor content of 0.37 and 0.44% and the highest leaf calcium content of 3.17 and 3.45% for both seasons, respectively. The lowest value of these parameters was found in the control (Ca0H0) treatment. It could be concluded of this experiment that the humic acid at level H10 and calcium chloride at level Ca150 improved vegetative characteristics and leaf mineral content gerbera plant cv. Yanara  

scholarly journals Salt-tolerance screening in Limonium sinuatum varieties with different flower colors

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Xiaojing Xu ◽  
Yingli Zhou ◽  
Ping Mi ◽  
Baoshan Wang ◽  
Fang Yuan
Keyword(s):  
Salt Tolerance ◽  
Photosynthetic Rate ◽  
Large Scale ◽  
Soluble Sugars ◽  
Dry Weight ◽  
Salt Gland ◽  
Salt Glands ◽  
Chlorophyll Contents ◽  
Relative Water ◽  
Whole Plants

AbstractLimonium sinuatum, a member of Plumbaginaceae commonly known as sea lavender, is widely used as dried flower. Five L. sinuatum varieties with different flower colors (White, Blue, Pink, Yellow, and Purple) are found in saline regions and are widely cultivated in gardens. In the current study, we evaluated the salt tolerance of these varieties under 250 mmol/L NaCl (salt-tolerance threshold) treatment to identify the optimal variety suitable for planting in saline lands. After the measurement of the fresh weight (FW), dry weight (DW), contents of Na+, K+, Ca2+, Cl−, malondialdehyde (MDA), proline, soluble sugars, hydrogen peroxide (H2O2), relative water content, chlorophyll contents, net photosynthetic rate, and osmotic potential of whole plants, the salt-tolerance ability from strongest to weakest is identified as Pink, Yellow, Purple, White, and Blue. Photosynthetic rate was the most reliable and positive indicator of salt tolerance. The density of salt glands showed the greatest increase in Pink under NaCl treatment, indicating that Pink adapts to high-salt levels by enhancing salt gland formation. These results provide a theoretical basis for the large-scale planting of L. sinuatum in saline soils in the future.

scholarly journals AVOCADO SEEDLINGS MULTIPLE STEMS PRODUCTION

2016 ◽  
Vol 38 (2) ◽  
Author(s):  
MARCUS VINICIUS SANDOVAL PAIXÃO ◽  
JOSÉ CARLOS LOPES ◽  
EDILSON ROMAIS SCHMILDT ◽  
RODRIGO SOBREIRA ALEXANDRE ◽  
CAROLINE MERLO MENEGHELLI
Keyword(s):  
Root Length ◽  
Dry Weight ◽  
Adventitious Rooting ◽  
Dry Mass ◽  
Stem Diameter ◽  
Experimental Unit ◽  
Shoot Height ◽  
Shoot Dry Weight ◽  
Federal Institute ◽  
Multiple Stems

ABSTRACT This study aimed to evaluate the potential of multi-stems in avocado seeds according to their mass as well as the adventitious rooting of multi-stem budding with or without the use of auxin. The research was carried out at the Vegetation House of Federal Institute of Espírito Santo, Campus Santa Teresa -ES, with seeds of different masses: <60 g, 61 to 80 g, 81 to 100 g and >100 g, in which each experimental unit was made of five seeds, distributed within five repetitions, under a completely randomized design. The seeds were put to germinate and the percentage number of emergence and multiple stems were evaluated. After 150 days, the following evaluations were carried out: survival of rooted cuttings; number of leaves; stem diameter; root length; root volume; root and shoot fresh mass; root and shoot dry mass; shoot height; absolute growth and shoot growth rate; shoot dry weight/root dry mass ratio; shoot height/stem diameter ratio; shoot height/root length and Dickson's quality index ratio. Avocado seeds with mass over 100 g and between 81-100 g presented higher percentage of multiple stems. Rods over 20 cm that were not treated with IBA (indole-3-butyric acid) resulted on avocado plants of better quality. The use of IBA (2000 mg L-1) does not affect the rooting and growth of avocado's multi-stem plants.

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