scholarly journals Effects of HPS and LED lighting on cucumber leaf photosynthesis, light quality penetration and temperature in the canopy, plant morphology and yield

2017 ◽  
Vol 26 (2) ◽  
Author(s):  
Liisa Elina Särkkä ◽  
Kari Jokinen ◽  
Carl-Otto Ottosen ◽  
Timo Kaukoranta
Keyword(s):  
Light Quality ◽  
Stem Elongation ◽  
Plant Morphology ◽  
Light Level ◽  
Yield Potential ◽  
Flower Initiation ◽  
Initiation Rate ◽  
Led Lighting ◽  
Use Efficiency ◽  
Lower Temperature

In Nordic countries during the winter months supplemental lighting is essential for year-round cucumber production. In this research the effects of full HPS (top and interlights) illumination is compared to hybrid (HPS top, LED interlights) and full LED (top and interlights). The results showed that fruit yield was highest in the HPS-LED treatment whereas the electrical use efficiency (kg yield J-1) increased when HPS was replaced with LED. In LED-LED the light use efficiency (g fruit FW mol-1 PAR) was highest but resulted in a fewer number of fruits in mid-winter particularly and the lowest yield potential. The lower temperature and lower light level due to LED-LED lighting lead to reduced photosynthesis capacity, flower initiation rate and water use efficiency whereas increased stem elongation and leaf expansion compared to other treatments. Differences in light quality of LED and HPS are also discussed in terms of cucumber yield formation.

scholarly journals 569 Photoselective Filters Affect Flowering and Stem Extension In Viola ×wittrockiana and Pisum sativum

HortScience ◽  
1999 ◽  
Vol 34 (3) ◽  
pp. 544D-544 ◽  
Author(s):  
Erik S. Runkle ◽  
Royal D. Heins
Keyword(s):  
Pisum Sativum ◽  
Light Quality ◽  
Stem Elongation ◽  
Plant Morphology ◽  
Photon Flux ◽  
Spectral Filters ◽  
Density Control ◽  
Long Day ◽  
Long Day Plants ◽  
Peduncle Length

For many plants, light quality has a pronounced effect on plant morphology; light with a low red (R, 600 to 700 nm) to far-red (FR, 700 to 800 nm) ratio promotes stem elongation and a high R: FR, or blue light (B, 400 to 500 nm), suppresses it. In addition, FR light is required for rapid flowering in some species, particularly for long-day plants. Our objective was to quantify how flexible spectral filters, which selectively reduce FR, B, or R, influence plant height and flowering of the quantitative long-day plants Pisum sativum L. `Utrillo' and Viola ×wittrockiana Gams. `Crystal Bowl Yellow'. Plants were grown at 20 °C with reduced FR, B, or R environments or with a neutral density control (C) filter. Calculated phytochrome photoequilebria were 0.78, 0.73, 0.71, or 0.46 for the altered FR, B, C, or R environments, respectively. All filter treatments transmitted a similar photosynthetic photon flux. Sixteen-hour photoperiods were created with natural daylight supplemented with high-pressure sodium lamps positioned above filters. Viola grown under the FR filter never reached 100% flowering within 8 weeks, and visible bud appearance was delayed by at least 17 days compared to all other filters. The R and B filters enhanced peduncle length by at least 25% compared to the C or FR filters. In Pisum, average internode length was 2.2, 2.9, 3.4, and 3.7 cm under the FR, C, B, and R filters, respectively, all statistically different. Fresh and dry shoot weights were similar under the C and FR filters but were at least 35% greater under the B filter and 35% lower under the R filter.

Evaluation of Finger Millet Varieties under Rainfed Condition of Eastern India

2017 ◽  
Vol 4 (03) ◽  
Author(s):  
M. K. Singh ◽  
VINOD KUMAR ◽  
SHAMBHU PRASAD
Keyword(s):  
Field Experiment ◽  
Finger Millet ◽  
Yield Potential ◽  
Growing Degree Days ◽  
Eastern India ◽  
Degree Days ◽  
Rainfed Condition ◽  
Net Returns ◽  
Humid Environment ◽  
Use Efficiency

A field experiment was carried out during the kharif of 2014 and 2015 to evaluate the yield potential, economics and thermal utilization in eleven finger millet varieties under the rainfed condition of the sub-humid environment of South Bihar of Eastern India. Results revealed that the significantly higher grain yield (20.41 q ha-1), net returns (Rs 25301) and B: C ratio (1.51) was with the finger millet variety ‘GPU 67’ but was being at par to ‘GPU28’and ‘RAU-8’, and significantly superior over remaining varieties. The highest heat units (1535.1oC day), helio-thermal units (7519.7oC day hours), phenothermal index (19.4 oC days day-1) were recorded with variety ‘GPU 67’ followed by ‘RAU 8’ and ‘GPU 28’ and lowest in ‘VL 149’ at 50 % anthesis stage. Similarly, the highest growing degree days (2100 oC day), helio-thermal units (11035.8 oC day hours) were noted with ‘GPU 67’ followed by ‘RAU 8’ and ‘GPU 28’ at maturity. The highest heat use efficiency (0.97 kg ha-1 oC day) and helio-thermal use efficiency (0.19 kg ha-1 oC day hour) were in ‘GPU 67’ followed by ‘VL 315’.

scholarly journals Elucidating the genetic basis of biomass accumulation and radiation use efficiency in spring wheat and its role in yield potential

2019 ◽  
Vol 17 (7) ◽  
pp. 1276-1288 ◽  
Author(s):  
Gemma Molero ◽  
Ryan Joynson ◽  
Francisco J. Pinera‐Chavez ◽  
Laura‐Jayne Gardiner ◽  
Carolina Rivera‐Amado ◽  
...  
Keyword(s):  
Spring Wheat ◽  
Genetic Basis ◽  
Biomass Accumulation ◽  
Radiation Use Efficiency ◽  
Yield Potential ◽  
Use Efficiency ◽  
Radiation Use

Identification of regulatory genes to improve nitrogen use efficiency

2014 ◽  
Vol 94 (6) ◽  
pp. 1009-1012 ◽  
Author(s):  
David R. Guevara ◽  
Yong-Mei Bi ◽  
Steven J. Rothstein
Keyword(s):  
Amino Acids ◽  
Transgenic Plants ◽  
Nitrogen Use Efficiency ◽  
Complex Traits ◽  
Regulatory Genes ◽  
Yield Potential ◽  
Environmental Damage ◽  
Nitrogen Use ◽  
Rice Plants ◽  
Use Efficiency

Guevara, D. R., Bi, Y.-M. and Rothstein, S. J. 2014. Identification of regulatory genes to improve nitrogen use efficiency. Can. J. Plant Sci. 94: 1009–1012. Crop production on soils containing sub-optimal levels of nitrogen (N) severely compromises yield potential. The development of crop varieties displaying high N use efficiency (NUE) is necessary in order to optimize N fertilizer use, and reduce the environmental damage caused by the current excessive application of N in agricultural areas. Genome-wide microarray analysis of rice plants grown under N-limiting environments was performed to identify NUE candidate genes. An early nodulin gene, OsENOD93-1, was strongly up-regulated during plant growth under low N. A constitutive Ubiquitin promoter was used to drive the expression of the OsENOD93-1 gene in transgenic plants to determine the importance of OsENOD93-1 for rice NUE. Transgenic rice plants over-expressing the OsENOD93-1 gene achieved ∼23% and 16% more yield and biomass, respectively, compared with wild-type plants when grown under N-limitation conditions. OsENOD93-1-OX transgenic plants accumulated a higher amount of total amino acids in the roots and xylem sap under N stress, suggesting that OsENOD93-1 plays a role in the transportation of amino acids. Taken together, we demonstrate that an effective way to identify NUE gene candidates involves both transcriptional profiling coupled with a transgenic validation approach to improve complex traits such as NUE in important crops.

scholarly journals Light Quality Environment and Photomorphological Responses of Young Olive Trees

Horticulturae ◽  
2021 ◽  
Vol 7 (10) ◽  
pp. 369
Author(s):  
Federico J. Ladux ◽  
Eduardo R. Trentacoste ◽  
Peter S. Searles ◽  
M. Cecilia Rousseaux
Keyword(s):  
Leaf Area ◽  
Light Quality ◽  
Plant Morphology ◽  
Cultivar Differences ◽  
Crop Species ◽  
Area Index ◽  
Canopy Development ◽  
Morphological Responses ◽  
Olive Trees ◽  
G Ratio

Tree densities have increased greatly in olive orchards over the last few decades. In many annual crop species, increased density reduces the horizontal red/far-red (R/FR) and blue/green (B/G) ratios during canopy development even before direct shading occurs, and such changes are known to alter plant morphology. This study with olive trees evaluated: (1) whether the leaf area index (LAI) of neighboring trees modifies the light quality environment prior to a tree being directly shaded and (2) the potential morphological responses of three olive cultivars to changes in light quality. Increasing LAI using different spatial arrangements of potted, three-year-old trees reduced the horizontal R/FR ratio more than that of the B/G ratio. Cultivar-specific responses to low R/FR ratio were observed for individual leaf area and aboveground/belowground biomass ratio using laterally positioned FR mirrors or green fences. No statistically significant responses were detected in response to green vegetation fences that reduced both horizontal R/FR and B/G ratios, but a cluster analysis grouped together the overall morphological responses to both FR mirrors and green fences. These results in olive trees suggest that cultivar differences in response to light quality may be relevant for understanding adaptation to dense orchards and identifying cultivars best suited to them.

scholarly journals MORPHOPHYSIOLOGICAL CHARACTERISTICS OF ARABIC COFFEE

Nativa ◽  
2021 ◽  
Vol 9 (1) ◽  
pp. 36-43
Author(s):  
Lucas Aparecido Manzani Lisboa ◽  
Matheus Luís Oliveira Cunha ◽  
Fernando Takayuki Nakayama ◽  
Paulo Alexandre Monteiro de Figueiredo ◽  
Ronaldo da Silva Viana ◽  
...  
Keyword(s):  
Plant Physiology ◽  
Coffea Arabica ◽  
Plant Morphology ◽  
Co2 Assimilation ◽  
Climatic Conditions ◽  
Assimilation Rate ◽  
Abaxial Epidermis ◽  
Internal Morphology ◽  
Use Efficiency ◽  
Best Fit

The understanding of the behavior of each cultivar under adverse climatic conditions is important in the choice of plants that best fit the region to be inserted. Due to the large number of cultivars available on the market it makes it difficult for producers to choose which material to plant. In view of the above, this study aimed to know the morphophysiological characteristics of coffee. The experimental design was in randomized blocks with 10 treatments, that is, arabic coffee varieties: Catuai IAC62; Catuai IAC99; Ouro IAC4397; Tupi RN IAC1669-13; Obatã IAC1669-20; Mundo Novo IAC379-24; Mundo Novo IAC 388-17-2; Mundo Novo SH3 Faz São José; Bourbon IACJ15 and Icatu IAC 2944-11 and with four replications totaling 40 plots, where each plot was composed of seven plants. The Mundo Novo IAC 388-17-2 coffee variety shows higher yield in the seventh year of cultivation. Variety of Bourbon IACJ15 coffee presented water use efficiency (EUW) which did not reflect in higher productivity. The Catuai V IAC99 arabica coffee variety stood out in the internal morphology of the leaves. The thickness of the adaxial and abaxial epidermis (TADE and TABE) and the CO2 assimilation rate (A) showed negative correlations with the productivity of processed coffee bags. Keywords: Coffea arabica; plant morphology; plant physiology; varieties.

Effect of drought stress on residual transpiration and its relationship with water use of wheat

1991 ◽  
Vol 71 (3) ◽  
pp. 695-702 ◽  
Author(s):  
J. M. Clarke ◽  
R. A. Richards ◽  
A. G. Condon
Keyword(s):  
Water Use Efficiency ◽  
Water Use ◽  
Transpiration Rate ◽  
Osmotic Potential ◽  
Water Status ◽  
Yield Potential ◽  
Cuticular Transpiration ◽  
Stress Treatment ◽  
Use Efficiency ◽  
Residual Transpiration

Increasing the water use efficiency (WUE) of wheat (Triticum spp.) has long been a goal in semiarid areas. Low rates of residual (cuticular) transpiration are thought to improve yield potential of wheat under dry conditions, although the linkage is tenuous. The objective of this work was to investigate the association of residual transpiration with water use, WUE, and leaf water status in hexaploid (T. aestivum L.) and tetraploid (T. turgidum L. var. durum) genotypes grown under two watering regimes in two glasshouse experiments. Single plants were grown in 0.1-m × 1-m (0.1-m × 0.5-m in exp. 2 low-stress treatment) PVC tubes filled with soil. The watering regimes consisted of weekly replenishment of water used (low stress), or addition of sufficient water to ensure plant survival (high stress). At anthesis, flag leaf residual transpiration (rate of water loss from excised leaves), stomatal conductance, relative water content (RWC), and osmotic potential (exp. 1 only) were measured. Water use was not correlated with residual transpiration rate in either experiment. Residual transpiration rate did not differ for the two stress treatments in exp. 1, but there were significant (P < 0.01) genotype by stress treatment interactions. Residual transpiration rate was not related to plant water status (leaf RWC or osmotic potential) as had been reported in other studies. Key words: Cuticular transpiration, water use efficiency, Triticum aestivum L., Triticum turgidum L. var. durum

scholarly journals Using QUEFTS model for estimating nutrient requirements of maize in the Northeast China

2017 ◽  
Vol 63 (No. 11) ◽  
pp. 498-504 ◽  
Author(s):  
Jiang Wenting ◽  
Liu Xiaohu ◽  
Qi Wen ◽  
Xu Xiaonan ◽  
Zhu Yucui
Keyword(s):  
Northeast China ◽  
Field Experiments ◽  
Nutrient Use Efficiency ◽  
Maize Yield ◽  
Yield Potential ◽  
Nutrient Requirements ◽  
Plant Nitrogen ◽  
Nutrient Use ◽  
Supply Surplus ◽  
Use Efficiency

Accurate estimating of the balanced nutrition for maize is necessary for optimizing fertilizer management to prevent nutrient supply surplus or deficiency. Data from 300 field experiments in the Northeast China conducted between 2006 and 2011 were gathered to study the characteristics of maize yield, and using the QUEFTS model to estimate the balanced nutrition at different yield potential. The average grain yield was 10 427 kg/ha, and average internal efficiencies were 54.3, 251.5 and 78.2 kg grain per kg plant nitrogen (N), phosphorus (P) and potassium (K), respectively. With the harvest index values &lt; 0.40 as outliers were excluded, the model simulated a linear-parabolic-plateau curve for the balanced N, P and K uptake when the initial yield target increased to the yield potential levels of 10 000 to 14 000 kg/ha. When the yield target reached approximately 60–70% of the yield potential, 16.7 kg N, 3.8 kg P, and 11.4 kg K were required to produce 1000 kg grain. The corresponding internal efficiencies were 60.0, 265.7 and 88.0 kg grain per kg plant N, P and K, respectively. These results contributed to improving nutrient use efficiency, and to demonstrate that the QUEFTS model could be a promising approach for estimating the balanced nutrition.

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