Vis–NIR spectroscopy: from leaf dry mass production estimate to the prediction of macro- and micronutrients in soybean crops

Some morphophysiological responses of Brachiaria brizantha cv. Marandu, cv. Piatã, cv. Arapoty, B163, B166 and B. ruziziensis R124 were compared in plants grown in pots, under flooded and well-drained conditions. Flooding reduced leaf elongation rate in all accessions. Leaf dry mass production was lower under flooding than in the control plants in all the studied accessions, except in cv. Piatã. Root dry mass production was reduced by flooding in cv. Marandu and in R124, while the proportion of biomass allocated to roots was reduced by flooding only in R124. It was not possible to detect significant differences between water regimes in the percentage of biomass allocated to culms and leaves for all accessions. Flooding decreased the number of tillers in cv. Marandu, in B163, B166 and in R124. Relative growth rate was decreased by flooding in cv. Marandu, in B163 and in R124. Flooding reduced gas exchange parameters in all accessions, but cv. Arapoty. The accessions tested differ in their relative tolerance to flooding. B. brizantha cv. Arapoty is considered the most tolerant. B. ruziziensis R124 is the most sensitive, followed by B. brizantha cv. Marandu. B. brizantha cv. Piatã, B163 and B166 are intermediate in flooding tolerance.

Download Full-text

Forage characters of different Paspalum species in Rio Grande do Sul: a meta-analysis

Ciência Rural ◽

10.1590/0103-8478cr20161049 ◽

2017 ◽

Vol 47 (7) ◽

Cited By ~ 1

Author(s):

Larissa Arnhold Graminho ◽

Miguel Dall’Agnol ◽

Luciana Pötter ◽

Rodrigo Ramos Lopes ◽

Carine Simioni ◽

...

Keyword(s):

Genetic Variability ◽

Mass Production ◽

Meta Analysis ◽

Rio Grande ◽

Dry Mass ◽

Rio Grande Do Sul ◽

Pasture Production ◽

Forage Plants ◽

Natural Pasture ◽

Leaf Dry Mass

ABSTRACT: The objective of this study was to evaluate, through meta-analysis, the forage characteristics of various species of the genus Paspalum and to use them to select the best ecotypes that can be used in artificial hybridization as parents and hybrids for pasture production and natural pasture recovery systems. Data were obtained from studies conducted by the Department of Forage Plants and Agrometeorology of the Universidade Federal do Rio Grande do Sul. Database comprised tests conducted with ecotypes and/or hybrids of Paspalum spp. in plots for evaluating total dry mass production, leaf dry mass production, and stem dry mass production by means of cuts. Total dry mass production, which included leaves and stems, differed between the ecotypes and hybrids. Hybrid H12 was the most divergent of all evaluated accessions. The greatest genetic divergence occurred due to dry mass production. Hybrids showed high total dry mass production, comprised mainly of leaves. Hybrid H12 and the accession of Paspalum lepton 28E were identified as the most dissimilar based on the generalized Mahalanobis distance using Tocher’s method. Total dry mass production is the characteristic that most contributed to the detection of genetic variability.

Download Full-text

Initial physic nut nutrition and potassium balance in the soil-plant system

Revista Brasileira de Engenharia Agrícola e Ambiental ◽

10.1590/s1415-43662014000500005 ◽

2014 ◽

Vol 18 (5) ◽

pp. 495-500 ◽

Cited By ~ 2

Author(s):

Mariângela B. Freiberger ◽

Iraê A. Guerrini ◽

Gustavo Castoldi ◽

Fábio Steiner ◽

Leonardo T. Büll

Keyword(s):

Mineral Nutrition ◽

Mass Production ◽

Mass Concentration ◽

Dry Mass ◽

Physic Nut ◽

Plant System ◽

Soil Fraction ◽

Potassium Fertilization ◽

Macro And Micronutrients ◽

Red Latosol

The objectives of this study were to evaluate the mineral nutrition and the response of physic nut to potassium fertilization as well as to assess whether the species can absorb K from the non-exchangeable soil fraction. The study was conducted in a greenhouse, in randomized blocks, and with four repetitions. Physic nut plants were cultivated in plastic recipients filled with 50 dm³ of a Dark Red Latosol fertilized with rates of 0, 40, 80, 120 and 160 mg K dm-3 of soil. One hundred and fifty days after planting, the height, stem diameter and leaf area of the plants were measured, and the dry mass, concentration in leaf and total accumulation of macro and micronutrients were determined, as well as the soil contents of exchangeable and non-exchangeable K. The K balance in the soil-plant system was also calculated. The increase of potassium fertilization resulted in a greater uptake of K, Ca and Mn but did not alter the total dry mass production of physic nut. The species can release and absorb K from the non-exchangeable soil fraction.

Download Full-text

Effect of plant regulators on growth and flowering of 'Meyer' zoysiagrass

Planta Daninha ◽

10.1590/s0100-83582013000300021 ◽

2013 ◽

Vol 31 (3) ◽

pp. 695-703 ◽

Cited By ~ 3

Author(s):

S.R. Marchi ◽

D. Martins ◽

N.V. Costa ◽

J.R.V. Silva

Keyword(s):

Plant Height ◽

Mass Production ◽

Untreated Control ◽

Block Design ◽

Dry Mass ◽

Zoysia Japonica ◽

Visual Effects ◽

Visual Symptoms ◽

Randomized Complete Block Design ◽

Prohexadione Calcium

This trial aimed to evaluate the effect of sequential applications of different plant regulators over growth and flower rachis emission of 'Meyer' zoysiagrass (Zoysia japonica). The study was conducted on 15-month old green turfgrass under a randomized complete block design with four replications. The following plant regulator and doses were tested: trinexapac-ethyl (113+113, 226+113, 226+226, 452+113, 452+226, 452+452, 678+339 e 904+452 g a.i./ha-1), prohexadione-calcium (100+100 e 200+200 g a.i. ha-1) and bispyribac-sodium (40+40 e 60+60 g a.i. ha-1), as well as an untreated control. The turfgrass was mowed again at 3.0 cm aboveground and the second plant regulator was applied when 'Meyer' zoysiagrass was between 5.0 and 6.0 cm high. The effect of the treatments was visually rated for visual injury, plant height, height and number of flower rachis, and total dry mass production of clippings. Only bispyribac-sodium had visual symptoms of injury on 'Meyer' zoysiagrass, and no intoxication was observed at 28 days after the second application (DAAB). The sequential applications of trinexapac-ethyl, prohexadione-calcium and bispyribac-sodium reduced by more than 80% the total clipping dry mass produced by 'Meyer' zoysiagrass. All the plant regulators tested also showed promising results in reducing the height and emission of rachis, especially when trinexapac-ethyl was applied at the doses 452+452, 678+339 and 904+452 g a.i. ha-1. 'Meyer' zoysiagrass turfgrass can be handled with the sequential application of a plant regulator, which reduces the need for mowing over a period up to 110 days after the application of the second plant regulator, and it also avoids deleterious visual effects over turfgrass.

Download Full-text

Physiological responses of two tropical weeds to shade: I. Growth and biomass allocation

Pesquisa Agropecuária Brasileira ◽

10.1590/s0100-204x1999000600004 ◽

1999 ◽

Vol 34 (6) ◽

pp. 944-952 ◽

Cited By ~ 1

Author(s):

Moacyr Bernardino Dias-Filho

Keyword(s):

Leaf Area ◽

Weed Management ◽

Dry Mass ◽

High Light ◽

Low Light ◽

Light Regimes ◽

Leaf Dry Mass ◽

Lower Ability ◽

Total Plant ◽

Plant Dry Mass

Ipomoea asarifolia (Desr.) Roem. & Schultz (Convolvulaceae) and Stachytarpheta cayennensis (Rich) Vahl. (Verbenaceae), two weeds found in pastures and crop areas in Brazilian Amazonia, were grown in controlled environment cabinets under high (800-1000 µmol m-² s-¹) and low (200-350 µmol m-² s-¹) light regimes during a 40-day period. For both species leaf dry mass and leaf area per total plant dry mass, and leaf area per leaf dry mass were higher for low-light plants, whereas root mass per total plant dry mass was higher for high-light plants. High-light S. cayennensis allocated significantly more biomass to reproductive tissue than low-light plants, suggesting a probably lower ability of this species to maintain itself under shaded conditions. Relative growth rate (RGR) in I. asarifolia was initially higher for high-light grown plants and after 20 days started decreasing, becoming similar to low-light plants at the last two harvests (at 30 and 40 days). In S. cayennensis, RGR was also higher for high-light plants; however, this trend was not significant at the first and last harvest dates (10 and 40 days). These results are discussed in relation to their ecological and weed management implications.

Download Full-text

Sensitivity of Shoots and Roots of Young Watermelon Plants to End-of-day Red and Far-red Light

Journal of the American Society for Horticultural Science ◽

10.21273/jashs.122.4.481 ◽

1997 ◽

Vol 122 (4) ◽

pp. 481-484

Author(s):

Heather A. Hatt Graham ◽

Dennis R. Decoteau

Keyword(s):

Citrullus Lanatus ◽

Red Light ◽

Dry Mass ◽

Stem Length ◽

Hoagland Solution ◽

Full Strength ◽

Leaf Dry Mass ◽

Half Strength

The sensitivity of shoots and roots to end-of-day (EOD) red (R) or far-red (FR) light on growth of `Sugar Baby' watermelon [Citrullus lanatus (Thunb.) Matsum & Nakai] was investigated. Plants were grown in full-strength Hoagland solution and treated for 14 days to 15 minutes EOD light in trial 1 and in half-strength Hoagland solution and treated for 10 days to EOD light in trial 2. Exposing shoots to EOD FR resulted in elongated petioles of leaves 1 to 3 (as counted from the cotyledons), internodes 1 to 3, and total stem length in both trials. Exposure to EOD FR resulted in increased stem and petiole dry mass in trial 1, whereas EOD FR resulted in increased root and leaf dry mass in trial 2. EOD FR exposure of roots increased the length of petiole 4 in trial 1. In general, shoots were more responsive than roots to the growth-regulating effects of EOD FR.

Download Full-text

FLAME RETARDANTS EFFECTS ON THE INITIAL GROWTH OF Schizolobium amazonicum HUBER EX DUCKE

Revista Árvore ◽

10.1590/1806-908820210000014 ◽

2021 ◽

Vol 45 ◽

Author(s):

Elen Silma Oliveira Cruz Ximenes ◽

Andréa Carvalho da Silva ◽

Adilson Pacheco de Souza ◽

Josiane Fernandes Keffer ◽

Alison Martins dos Anjos ◽

...

Keyword(s):

Flame Retardant ◽

Leaf Area ◽

Flame Retardants ◽

Biomass Accumulation ◽

Dry Mass ◽

Initial Growth ◽

Environmental Implications ◽

Leaf Dry Mass ◽

Height Increase ◽

Positive Effect

ABSTRACT Flame retardants are efficient in fighting wildfire; however, their environmental implications, especially regarding the vegetation, need to be clarified. This work aimed at assessing the effects of flame retardant on the initial growth of Schizolobium amazonicum. Treatments consisted in applying different flame retardant concentrations via substrate and leaf: Phos-Chek WD-881® (0, 3.00, 6.00, 8.00 and 10.00 mL L-1), Hold Fire® (0, 7.00, 9.00, 12.00 and 15.00 mL L-1) and water-retaining polymer Nutrigel® used as alternative retardant (0, 0.25, 0.50, 0.75 and 1.00 g L-1). Growth analyses were carried out to assess the effects of these substances (10 repetitions per treatment). The aliquot of 10.00 mL L-1 of Phos-Chek WD881 applied on the leaves led to an increase of 70% in leaf area and 15% in seedling height. The same Phos-Chek concentration favored height increase (32%) and total dry mass accumulation (33%) throughout time. The concentration of 15 mL L-1 of Hold Fire® applied on leaves, compromised 45% the accumulation of dry biomass in the seedling. Initially, 1.00 g L-1 of Nutrigel® applied via substrate led to an increase of 70% in leaf area, 29% in plant height, and 89% in leaf dry mass. Therefore, Phos-Chek applied on leaves favored shoot growth in S. amazonicum. Hold Fire® applied on leaves impaired biomass accumulation in seedlings. Nutrigel® applied on substrate does not cause long-lasting damage to the initial growth of S. amazonicum. The aliquot of 0.50 g L-1 administered via polymer leave had positive effect on seedling shoot.

Download Full-text

Intercropping of sorghum with Paiaguas palisadegrass in a crop-livestock integration system for pasture recovery

Australian Journal of Crop Science ◽

10.21475/ajcs.20.14.07.p2216 ◽

2020 ◽

pp. 1072-1080

Author(s):

Charles Barbosa Santos ◽

Kátia Aparecida de Pinho Costa ◽

Wender Ferreira de Souza ◽

Alessandro Guerra da Silva ◽

Victor Costa e Silva ◽

...

Keyword(s):

Mass Production ◽

Block Design ◽

Dry Mass ◽

Forage Production ◽

Integration System ◽

Initial Development ◽

Sustainable Systems ◽

Randomized Block Design ◽

Forage Species ◽

Sorghum Grain

Intercropping systems have become an interesting alternative for grain and forage production because they are sustainable systems that reduce carbon emissions in degraded pasture areas. However, few studies have used forage species recently introduced into the market, and more studies that assess the performances of these species in integrated systems are needed. Therefore, the objective of this study was to evaluate the agronomic characteristics of intercropped sorghum and Paiaguas palisadegrass (including the species name) in a crop-livestock integration system for pasture recovery. The field experiment was conducted in the municipality of Rio Verde, Goiás, Brazil, using a randomized block design with four replications. The treatments consisted of the following forage systems: monocropping of sorghum, monocropping of Paiaguas palisadegrass, row intercropping of sorghum with Paiaguas palisadegrass, interrow intercropping of sorghum with Paiaguas palisadegrass and intercropping of sorghum with oversown Paiaguas palisadegrass. To obtain a desired population of 240,000 plants ha-1, 12 seeds of sorghum and 5 kg of viable pure seeds of the forage species were planted per meter and hectare, respectively. The growth of Paiaguas palisadegrass in the same row as sorghum reduced the sorghum grain yield. The intercropping of sorghum with oversown Paiaguas palisadegrass hindered the initial development of Paiaguas palisadegrass in terms of plant height and number of tillers due to shading, and this effect was reflected in the dry mass production. Row and interrow intercropping provided higher dry mass production without affecting the forage quality. Therefore, the interrow intercropping of sorghum with Paiaguas palisadegrass was found to be a promising agricultural technique for grain and forage production that could be used for the establishment of new pastures or pasture recovery.

Download Full-text

The behaviour of plants in various gas mixtures

Proceedings of the Royal Society of London Series B Biological Sciences ◽

10.1098/rspb.1971.0089 ◽

1971 ◽

Vol 179 (1056) ◽

pp. 177-188

Keyword(s):

Carbon Dioxide ◽

Gas Exchange ◽

Partial Pressure ◽

Higher Plants ◽

Dry Mass ◽

Carbon Dioxide Partial Pressure ◽

Ambient Oxygen ◽

Leaf Dry Mass ◽

Rate Of Photosynthesis ◽

Effect Of Oxygen

The effects of the composition and pressure of the ambient gas mixture on the diffusive gas exchange of leaves, and the effects of carbon dioxide and oxygen on respiration and photosynthesis are described. When photosynthesis is limited by the rate at which carbon dioxide reaches the chloroplasts, the net rate of photosynthesis of many (but not all) plant species depends on the ambient oxygen partial pressure. The effect of oxygen may be principally to stimulate a respiratory process rather than to inhibit carboxylation. However, when photosynthesis is not limited by the carbon dioxide supply, this respiratory process seems to be suppressed. The gas exchange of plant communities responds to the aerial environment in the way expected from measurements on single leaves, but the growth response to a given difference in gas composition is smaller than expected because of adaptation, notably in the ratio of leaf dry mass to leaf area. It is concluded that the growth rate of higher plants in given illumination will be independent of the partial pressure of oxygen and of other gases likely to be used to dilute it, provided that the carbon dioxide partial pressure is so adjusted (probably to not more than 2 mbar (200 Pa)) that the rate of photosynthesis is not limited by the rate of diffusion to the chloroplasts.

Download Full-text