scholarly journals Can morpho-physiological responses to natural light conditions in Cybistax antisyphilitica (Mart.) Mart. explain its widespread occurrence in Brazilian Savannas?

Flora ◽  
2021 ◽  
pp. 151990
Author(s):  
Fernanda Monteiro de Freitas ◽  
André R. Terra Nascimento ◽  
Maria Cristina Sanches
Keyword(s):  
Physiological Responses ◽  
Natural Light ◽  
Light Conditions ◽  
Widespread Occurrence

Morpho-physiological responses in Cedrela fissilis Vell. submitted to changes in natural light conditions: implications for biomass accumulation

Trees ◽  
2016 ◽  
Vol 31 (1) ◽  
pp. 215-227 ◽  
Author(s):  
Maria Cristina Sanches ◽  
Juliana Marzinek ◽  
Natália G. Bragiola ◽  
André R. Terra Nascimento
Keyword(s):  
Physiological Responses ◽  
Biomass Accumulation ◽  
Natural Light ◽  
Light Conditions

scholarly journals Fluctuating light experiments and semi-automated plant phenotyping enabled by self-built growth racks and simple upgrades to the IMAGING-PAM

Plant Methods ◽  
2019 ◽  
Vol 15 (1) ◽  
Author(s):  
Dominik Schneider ◽  
Laura S. Lopez ◽  
Meng Li ◽  
Joseph D. Crawford ◽  
Helmut Kirchhoff ◽  
...  
Keyword(s):  
Data Analysis ◽  
Low Cost ◽  
Growth Conditions ◽  
Research Field ◽  
Constant Light ◽  
Plant Phenotyping ◽  
Natural Light ◽  
Light Conditions ◽  
Fluctuating Light ◽  
Science Labs

Abstract Background Over the last years, several plant science labs have started to employ fluctuating growth light conditions to simulate natural light regimes more closely. Many plant mutants reveal quantifiable effects under fluctuating light despite being indistinguishable from wild-type plants under standard constant light. Moreover, many subtle plant phenotypes become intensified and thus can be studied in more detail. This observation has caused a paradigm shift within the photosynthesis research community and an increasing number of scientists are interested in using fluctuating light growth conditions. However, high installation costs for commercial controllable LED setups as well as costly phenotyping equipment can make it hard for small academic groups to compete in this emerging field. Results We show a simple do-it-yourself approach to enable fluctuating light growth experiments. Our results using previously published fluctuating light sensitive mutants, stn7 and pgr5, confirm that our low-cost setup yields similar results as top-prized commercial growth regimes. Moreover, we show how we increased the throughput of our Walz IMAGING-PAM, also found in many other departments around the world. We have designed a Python and R-based open source toolkit that allows for semi-automated sample segmentation and data analysis thereby reducing the processing bottleneck of large experimental datasets. We provide detailed instructions on how to build and functionally test each setup. Conclusions With material costs well below USD$1000, it is possible to setup a fluctuating light rack including a constant light control shelf for comparison. This allows more scientists to perform experiments closer to natural light conditions and contribute to an emerging research field. A small addition to the IMAGING-PAM hardware not only increases sample throughput but also enables larger-scale plant phenotyping with automated data analysis.

scholarly journals Development of an automatic visual grading system for grafting seedlings

2017 ◽  
Vol 9 (1) ◽  
pp. 168781401668626 ◽  
Author(s):  
Subo Tian ◽  
Zifan Wang ◽  
Jifeng Yang ◽  
Zichen Huang ◽  
Ruili Wang ◽  
...  
Keyword(s):  
Image Processing ◽  
Computer Vision ◽  
Grading System ◽  
Natural Light ◽  
Maximum Frequency ◽  
Light Conditions ◽  
Visual Grading ◽  
Key Technology ◽  
Background Light ◽  
Blue Background

In this study, a visual grading system of vegetable grafting machine was developed. The study described key technology of visual grading system of vegetable grafting machine. First, the contrasting experiment was conducted between acquired images under blue background light and natural light conditions, with the blue background light chosen as lighting source. The Visual C++ platform with open-source computer vision library (Open CV) was used for the image processing. Subsequently, maximum frequency of total number of 0-valued pixels was predicted and used to extract the measurements of scion and rootstock stem diameters. Finally, the developed integrated visual grading system was experimented with 100 scions and rootstock seedlings. The results showed that success rate of grading reached up to 98%. This shows that selection and grading of scion and rootstock could be fully automated with this developed visual grading system. Hence, this technology would be greatly helpful for improving the grading accuracy and efficiency.

Studies on reflexion of light from silvery surfaces of fishes, with special reference to the bleak, Alburnus alburnus

1965 ◽  
Vol 45 (3) ◽  
pp. 683-703 ◽  
Author(s):  
E. J. Denton ◽  
J. A. C. Nicol
Keyword(s):  
Special Reference ◽  
Aquatic Environment ◽  
The Body ◽  
Natural Light ◽  
Light Conditions ◽  
Trachurus Trachurus ◽  
Reflecting Surfaces ◽  
Bleak Alburnus Alburnus ◽  
Different Parts

The problem of how a fish can make itself invisible in the natural light-conditions in an aquatic environment is discussed with particular reference to the silvery surfaces of fish.In fish which we have examined, the silvery surfaces are of two types: (1) an argenteum which consists of long thin crystals of guanine whose reflecting surfaces are approximately parallel with the surface of the fish; (2) layers of guanine crystals lying either on the inner surfaces of the scales or in the subdermis—these crystals are not, in general, orientated with their reflecting surfaces parallel with the surfaces of the fish, and are much broader than those of the argenteum.Methods are described by which the orientation of the crystal planes with respect to the planes of the scales on which they lie can be determined.The orientation of the crystals of type 2 in different parts of the body is described for the horse mackerel, Trachurus trachurus (L.), and for the bleak, Alburnus alburnus (L.).For the bleak it is shown that although the planes of the crystals are often very much inclined with respect to the planes of the scales, the long axes of the crystals are always approximately parallel with the planes of scales. The inclination of the crystals, therefore, is away from the scales across their short axes.Measurements of the light transmitted by silvery scales of the bleak show that they reflect light strongly when this falls obliquely on the crystals which they contain and that they are most transparent to light which strikes the scales in a direction perpendicular to the reflecting planes of the crystals.

scholarly journals Performance of growing pigs subjected to lighting programs in climate-controlled environments

2020 ◽  
Vol 24 (9) ◽  
pp. 616-621
Author(s):  
Janice M. C. Barnabé ◽  
Héliton Pandorfi ◽  
Nicoly F. Gomes ◽  
Marco A. C. Holanda ◽  
Mônica C. R. Holanda ◽  
...  
Keyword(s):  
Cooling System ◽  
Physiological Responses ◽  
Evaporative Cooling ◽  
Growing Pigs ◽  
Semiarid Region ◽  
Natural Light ◽  
Artificial Light ◽  
Feed Conversion ◽  
Climate Control ◽  
And Performance

ABSTRACT The objective of this research was to evaluate the thermal comfort, physiological responses and performance of pigs in the growth phase, subjected to supplemental lighting programs in air-conditioned environments, in semiarid region of Pernambuco state, Brazil. Twenty-seven pigs (3/4 Duroc, ¼ Pietrain) were subjected to pens with no climate control, pens with forced ventilation and pens with adiabatic evaporative cooling, associated with 12 h of natural light, 12 h of natural light + 4 h of artificial light and 12 h of natural light + 6 h of artificial light. The experimental design was completely randomized, in a 3 x 3 factorial arrangement with three repetitions. Meteorological responses, physiological responses and performance variables of the animals were recorded. The evaporative cooling system attenuated the action of the stressors and ensured adequate thermal conditions for the animals. Respiratory rate and rectal temperature indicated that evaporative cooling ensured the maintenance of homeothermy. Weight gain and feed conversion were positively influenced for the animals exposed to evaporative cooling, but without significant effect of lighting programs.

scholarly journals Fluctuating light experiments and semi-automated plant phenotyping enabled by self-built growth racks and simple upgrades to the IMAGING-PAM

2019 ◽  
Author(s):  
Dominik Schneider ◽  
Laura S. Lopez ◽  
Meng Li ◽  
Joseph D. Crawford ◽  
Helmut Kirchhoff ◽  
...  
Keyword(s):  
Data Analysis ◽  
Low Cost ◽  
Growth Conditions ◽  
Research Field ◽  
Constant Light ◽  
Plant Phenotyping ◽  
Natural Light ◽  
Light Conditions ◽  
Fluctuating Light ◽  
Science Labs

AbstractBackgroundOver the last years, several plant science labs have started to employ fluctuating growth light conditions to simulate natural light regimes more closely. Many plant mutants reveal quantifiable effects under fluctuating light despite being indistinguishable from wild-type plants under standard constant light. Moreover, many subtle plant phenotypes become intensified and thus can be studied in more detail. This observation has caused a paradigm shift within the photosynthesis research community and an increasing number of scientists are interested in using fluctuating light growth conditions. However, high installation costs for commercial controllable LED setups as well as costly phenotyping equipment can make it hard for small academic groups to compete in this emerging field.ResultsWe show a simple do-it-yourself approach to enable fluctuating light growth experiments. Our results using previously published fluctuating light sensitive mutants, stn7 and pgr5, confirm that our low-cost setup yields similar results as top-prized commercial growth regimes. Moreover, we show how we increased the throughput of our Walz IMAGING-PAM, also found in many other departments around the world. We have designed a Python and R-based open source toolkit that allows for semi-automated sample segmentation and data analysis thereby reducing the processing bottleneck of large experimental datasets. We provide detailed instructions on how to build and functionally test each setup.ConclusionsWith material costs well below USD$1000, it is possible to setup a fluctuating light rack including a constant light control shelf for comparison. This allows more scientists to perform experiments closer to natural light conditions and contribute to an emerging research field. A small addition to the IMAGING-PAM hardware not only increases sample throughput but also enables larger-scale plant phenotyping with automated data analysis.

Photoperception and de-etiolation

1983 ◽  
Vol 303 (1116) ◽  
pp. 489-501 ◽  
Keyword(s):  
Gene Expression ◽  
Signal Transduction ◽  
Environmental Factor ◽  
Present Article ◽  
Time Course ◽  
Higher Plants ◽  
Natural Light ◽  
Light Conditions ◽  
Strategy Of Development ◽  
Single Well

In seedlings or sprouts of higher plants, photomorphogenesis is the strategy of development if and as long as abundant light is available, and scotomorphogenesis (etiolation) is the developmental strategy of choice as long as light is not yet, or no longer, available. The transition from scotomorphogenesis to photomorphogenesis (called de-etiolation) can be considered a process in which a single, well defined environmental factor causes a plant to change its pattern of gene expression. The present article focuses on the question: what is the photosensory system, including photoreception and signal transduction, through which a plant can detect those light conditions that justify the (gradual) shift from scotomorphogenesis to photomorphogenesis, i.e. de-etiolation, which implies a strong and partly irreversible investment of m atter and energy? The significance of phytochrome for signal reception, the mode of signal expression, and the time course of signal transduction in phytochromemediated responses are reviewed briefly. The emphasis is on amplification of the phytochrome signal by red, blue and ultraviolet light (measured as responsivity amplification) because these recent findings may lead to a better understanding of the responses of plants under natural light conditions.

Sign in / Sign up

Export Citation Format

Share Document