scholarly journals How does structure matter? Comparison of canopy photosynthesis using one- and three-dimensional light models: a case study using greenhouse cucumber canopies

2021 ◽  
Author(s):  
Yi-Chen Pao ◽  
Katrin Kahlen ◽  
Tsu-Wei Chen ◽  
Dirk Wiechers ◽  
Hartmut Stützel
Keyword(s):  
Dry Matter ◽  
Empirical Relationship ◽  
Three Dimensional ◽  
Light Interception ◽  
Efficient Estimation ◽  
Light Extinction ◽  
Photosynthetic Parameters ◽  
Area Index ◽  
K Value ◽  
Greenhouse Cucumber

Abstract One-dimensional light models using the Beer-Lambert equation (BL) with the light extinction coefficient k are simple and robust tools for estimating light interception of homogeneous canopies. Functional-structural plant models (FSPMs) are powerful to capture light-plant interactions in heterogeneous canopies, but they are also more complex due to explicit descriptions of three-dimensional plant architecture and light models. For choosing an appropriate modelling approach, the trade-offs between simplicity and accuracy need to be considered when canopies with spatial heterogeneity are concerned. We compared two light modelling approaches, one following BL and another using ray tracing (RT), based on a framework of a dynamic FSPM of greenhouse cucumber. Resolutions of hourly-step (HS) and daily-step (DS) were applied to simulate light interception, leaf-level photosynthetic acclimation and plant-level dry matter production over growth periods of two to five weeks. Results showed that BL-HS was comparable to RT-HS in predicting shoot dry matter and photosynthetic parameters. The k used in the BL approach was simulated using an empirical relationship between k and leaf area index established with the assistance of RT, which showed variation up to 0.2 in k depending on canopy geometry under the same plant density. When a constant k value was used instead, a difference of 0.2 in k resulted in up to 27% loss in accuracy for shoot dry matter. These results suggested that, with the assistance of RT in k estimation, the simple approach BL-HS provided efficient estimation for long-term processes.

scholarly journals Differential Influences of Leaf Tip Trimming on Light Interception and Dry Matter Production in Tomato Dutch Cultivar Gourmet and Japanese Cultivar Momotaro York

HortScience ◽  
2017 ◽  
Vol 52 (5) ◽  
pp. 686-691 ◽  
Author(s):  
Tadahisa Higashide ◽  
Yuya Mochizuki ◽  
Takeshi Saito ◽  
Yasushi Kawasaki ◽  
Dong-Hyuk Ahn ◽  
...  
Keyword(s):  
Leaf Area ◽  
Dry Matter ◽  
Leaf Shape ◽  
Light Interception ◽  
Light Extinction ◽  
Area Index ◽  
Mature Leaves ◽  
Significant Difference ◽  
Young Leaves ◽  
Japanese Cultivar

To investigate the influence of morphological changes in individual leaves of tomato on light interception and dry matter (DM) production, we altered leaf shape by trimming leaflets of young or mature leaves of the Dutch cultivar Gourmet and the Japanese cultivar Momotaro York. Young leaves 5-cm long were trimmed of their first and second leaflets from the leaf apex. Mature leaves were similarly trimmed at ≥71 days after transplanting (DAT). The individual leaf area (LA) of intact ‘Momotaro York’ leaves was significantly larger than that of ‘Gourmet’. Light–photosynthesis curves of the cultivars were almost identical. Mature-trimmed plants of both cultivars had a smaller individual LA and a smaller leaf area index (LAI), and a greater light-extinction coefficient (LEC). Although there was no significant difference in light-use efficiency (LUE) (i.e., DM production per unit intercepted solar radiation) in ‘Gourmet’ between trimming stages, LUE of ‘Momotaro York’ was decreased significantly by young-leaf trimming. Trimming of young leaves significantly decreased the LEC in ‘Gourmet’ but increased it in ‘Momotaro York’. Although leaf trimming would be impractical for commercial cultivation, these results may provide with a clue for breeding for yield improvement.

Light extinction coefficients specific to the understory vegetation of the southern boreal forest, Quebec

2000 ◽  
Vol 30 (1) ◽  
pp. 168-177 ◽  
Author(s):  
Isabelle Aubin ◽  
Marilou Beaudet ◽  
Christian Messier
Keyword(s):  
Boreal Forest ◽  
Leaf Area Index ◽  
Light Transmission ◽  
Light Availability ◽  
Understory Vegetation ◽  
Light Extinction ◽  
Forest Types ◽  
Area Index ◽  
K Value ◽  
Extinction Coefficients

This study was conducted in six different forest types in Abitibi, Que., (i) to identify the factors that most influence understory light transmission in the southern boreal forest and (ii) to develop light extinction coefficients (k), which could be used to simulate light transmission in the understory. Light availability and understory vegetation (cover, composition, vertical distribution, and leaf area index) were characterized within three strata (0.05-5 m) in a total of 180 quadrats. Calculated k values were based on measured light availability and leaf area index. These values varied among forest types, strata, understory vegetation types, and cover in the upper stratum. The highest k values were generally associated with a dense stratum of Acer spicatum Lam. We developed five sets of k values based on the factors that most affected light transmission. Measured transmission (Tm) was compared with transmission predicted (Tp) from each set of k values. Light transmission predicted using a single k value (mean k = 0.54) underestimated Tm. More accurate predictions were obtained when we used the other four sets of k values. Our results indicate that, in the southern boreal forest, the understory vegetation can be quite heterogeneous and patterns of light transmission cannot be accurately simulated using a unique k value. However, the various sets of k values developed in this study could be used in prediction models of forest dynamics to obtain relatively good predictions of understory light extinction in forest types similar to the ones studied here.

scholarly journals Cluster and Principle Component Analysis of Soybean Grown at Various Row Spacings, Planting Dates and Plant Populations

2018 ◽  
Vol 3 (1) ◽  
pp. 110-121 ◽  
Author(s):  
Charanjit Singh Kahlon ◽  
Bin Li ◽  
James Board ◽  
Mahendra Dia ◽  
Parmodh Sharma ◽  
...  
Keyword(s):  
Cluster Analysis ◽  
Leaf Area Index ◽  
Leaf Area ◽  
Dry Matter ◽  
Light Interception ◽  
Plant Population ◽  
Large Set ◽  
Planting Dates ◽  
Area Index ◽  
Principle Components Analysis

Abstract Increased light interception (LI), along with concomitant increases in crop growth rate (CGR), is the main factor explaining how cultural factors such as row spacing, plant population, and planting date affect soybean yield. Leaf area index (LAI), LI, and CGR are interrelated in a “virtuous spiral” where increased LAI leads to greater LI resulting in a higher CGR and more total dry matter per area (TDM). This increases LAI, thus accelerating the entire physiological process to a higher level. A greater understanding of this complex growth dynamic process could be achieved through use of cluster analysis and principle components analysis (PCA). Cluster analysis involves grouping of similar objects in such way that objects in same cluster are similar to each other and dissimilar to objects in other cluster. PCA is a technique used to reduce a large set of variables to a few meaningful ones. Seasonal relative leaf area index (RLAI), relative light interception (RLI), and relative total dry matter (RTDM) response curves were determined from the data by a stepwise regression analysis in which these parameters were regressed against relative days after emergence (RDAE). Greatest levels of RLAI, RLI and RTDM were observed in soybean planted early on narrow row spacings and recorded greater plant population. In contrast, lower levels of these parameters occurred on plants with wide row spacings at late planting dates. For farmers, these results are useful in terms of adopting certain cultural practices which can help in the management of stress in soybean.

Analysis of the regrowth of a tropical grass/legume sward subjected to different frequencies and intensities of defoliation

1980 ◽  
Vol 31 (4) ◽  
pp. 673 ◽  
Author(s):  
MM Ludlow ◽  
DA Charles-Edwards
Keyword(s):  
Leaf Area ◽  
Dry Matter ◽  
Dry Weight ◽  
Light Interception ◽  
Photosynthetic Characteristics ◽  
Dry Matter Production ◽  
Canopy Photosynthesis ◽  
Area Index ◽  
Matter Production ◽  
Cutting Height

Dry weight, leaf area, light interception and canopy photosynthesis were measured during 3- or 5-week regrowth periods of Setaria anceps/Desmodium intortum swards cut to 7.5 or 15 cm. Dry matter production during the experiment and over the growing season increased with cutting height and with interval between defoliations, but the proportion of grass to legume was unaffected. These effects of defoliation on dry matter production were similar to those estimated for integrated canopy photosynthesis from measured light interception and calculated leaf photosynthetic characteristics. Height and frequency of defoliation had no effect on canopy extinction coefficient for light, nor on the leaf photosynthetic characteristics, except for the first 1-2 weeks after defoliation when leaf photosynthetic rates appeared to be depressed. The main effects of height and frequency of defoliation on dry matter production were through their effects on leaf area index and light interception.

scholarly journals Analysis of Growth and Yield of Three Types Cucumbers (Cucumis sativus L.) Based on Yield Components

Horticulturae ◽  
2021 ◽  
Vol 8 (1) ◽  
pp. 33
Author(s):  
Kazuya Maeda ◽  
Dong-Hyuk Ahn
Keyword(s):  
Yield Components ◽  
Dry Matter ◽  
Dry Weight ◽  
Fruit Yield ◽  
Growth And Yield ◽  
Light Extinction ◽  
Dry Matter Content ◽  
Fresh Weight ◽  
Cucumis Sativus L ◽  
Area Index

The objectives of this study were to evaluate the yield of different types of cucumbers from the perspective of yield components. The yield and yield components of nine cucumber cultivars (Beit Alpha, Greenhouse, and Japanese) grown hydroponically in a greenhouse were investigated. Fruit yield fresh weight in the Beit Alpha type was higher than that of the Japanese type, and the fruit yield fresh weight was significantly correlated with fruit yield dry weight, total dry matter (TDM), fraction of fruits, and number of fruits. However, the fruit yield fresh weight was not significantly correlated with intercepted light, light use efficiency (LUE), leaf area index, light extinction coefficient, and fruit dry matter content. High fruit yield dry weight was associated with a high TDM and the fraction of fruits. Moreover, the high TDM and fraction of fruits were associated with LUE and the number of fruits, respectively.

Density and row spacing effects on irrigated short wheats at low latitude

1976 ◽  
Vol 87 (1) ◽  
pp. 137-147 ◽  
Author(s):  
R. A. Fischer ◽  
I. Aguilar M. ◽  
R. Maurer O. ◽  
S. Rivas A.
Keyword(s):  
Grain Yield ◽  
Dry Matter ◽  
Light Interception ◽  
Dry Matter Production ◽  
Seeding Density ◽  
High Fertility ◽  
Dry Matter Accumulation ◽  
Area Index ◽  
Matter Production ◽  
Very High

SummaryDuring four winter seasons eight spacing and density experiments were made under irrigated high fertility conditions in north-west Mexico (latitude 27° N). Experiments included various Triticum aestivum and T. durum genotypes of spring habit, short stature derived from Norin 10 genes, and contrasting plant type. Measurements included dry-matter production, photosynthetic area index, and light interception during one experiment, total dry matter at maturity in most others and grain yield and its numerical components in all experiments.Grain yield and most other crop characters were unaffected by row spacings within the range 10–45 cm interrow width. The optimal seeding density for maximum grain yield was 40–100 kg/ha (80–200 plants/m2). Yield reductions at lower densities (20, 25 kg/ha) were slight and accompanied by reduced total dry-matter production. Yield reductions at higher densities (160–300 kg/ha) were also slight and were associated with more spikes/m2 but fewer grains/m2 and reduced harvest index. It is suggested that lower than normal preanthesis solar radiation or weather conditions leading to lodging can magnify these yield depressions at higher densities.Measurements showed rapid approach of crops to 95% light interception, reached even at a density of 50 kg/ha within 50 days of seeding. It is suggested that provided this occurs before the beginning of substantial dry-matter accumulation in the growing spikes (60 days after seeding) there will be no loss of grain yield with reduced seeding density. Results point to a ceiling photosynthetic area index for maximum crop growth rate although there was a tendency for rates to fall at very high indices (> 9). This tendency was associated with very high density, high maximum numbers of shoots, poor survival of shoots to give spikes (< 30%) and reduced number of grains/m3;. The relatively low optimal densities seen here may be characteristic of genotypes derived from Norin 10.Genotype × spacing, genotype × density and spacing × density interactions were generally non-significant and always small. There was a tendency for the presence of non-erect leaves or branched spikes to reduce the optimal density, but large differences in tillering capacity had no influence. Differences in lodging susceptibility can however lead to substantial genotype x density interactions.

Light interception and utilization in determinate and indeterminate cultivars of Vicia faba under contrasting plant distributions and population densities

1991 ◽  
Vol 116 (3) ◽  
pp. 395-407 ◽  
Author(s):  
H. Stützel ◽  
W. Aufhammer
Keyword(s):  
Population Density ◽  
Field Experiment ◽  
Dry Matter ◽  
Light Interception ◽  
Light Extinction ◽  
Dry Matter Production ◽  
Population Densities ◽  
Extinction Coefficients ◽  
Matter Production ◽  
Reduced Light

SUMMARYIn a 2-year field experiment at Hohenheim in 1987–88, with an intact or partly deflowered indeterminate cultivar and a determinate cultivar, light interception and dry matter production were highest in crops grown in isometric stands (equal distances between plants), lowest in double rows and intermediate in single rows. Dry matter production was greater at high than at low population density and in the wetter and cooler weather of 1987. Population density had a greater effect on DM production than on light interception. The greater leaf canopies under high density and in 1987 (Stützel & Aufhammer 1991) reduced light extinction coefficients. In the determinate cultivar, light extinction coefficients were consistently higher and light use efficiencies were consistently lower than in the indeterminate cultivar. Deflowering the indeterminate genotype and different planting designs did not change light use efficiencies and light extinction coefficients. In general, differences in light use efficiencies were inversely related to differences in light extinction coefficients.

Irrigation strategy, nitrogen application and fungicide control in winter wheat on a sandy soil. II. Radiation interception and conversion

2000 ◽  
Vol 134 (1) ◽  
pp. 13-23 ◽  
Author(s):  
J. E. OLESEN ◽  
L. N. JØRGENSEN ◽  
J. V. MORTENSEN
Keyword(s):  
Winter Wheat ◽  
Dry Matter ◽  
Nitrogen Concentration ◽  
Relative Increase ◽  
Light Interception ◽  
First Year ◽  
Nitrogen Rate ◽  
Good Correspondence ◽  
Area Index ◽  
Crop Area

Data from a three factor experiment carried out during two years were used to analyse the effects of drought, nitrogen and disease on light interception (IPAR) and radiation use efficiency (RUE) in winter wheat (Triticum aestivum L.). The factors in the experiment comprised four irrigation strategies including no irrigation, three nitrogen levels providing 67, 83 and 100% of the recommended nitrogen rate, and two strategies for control of leaf diseases (with and without fungicides). Light interception was estimated from weekly measurements of crop spectral reflectance. This method was compared with estimates derived from crop area index measured by plant samples or by using the LAI2000 instrument. There was a good correspondence between the different methods before anthesis, but an overestimation of light interception with the methods using crop area index after anthesis due to an increase in non-photosynthetic active leaf area. Irrigation increased both IPAR and RUE. The relative increase in IPAR for irrigation was greater than the relative increase in RUE in the first year, whereas they were of similar size in the second year. The differences between the years could be attributed to changes in timing of the drought relative to crop ontogenesis. Increasing nitrogen rate increased IPAR, but caused a small decrease in RUE in both years. This reduction in RUE with increasing nitrogen concentration in leaves was also found to be significant when disease levels and drought effects were included in a multiple linear regression. Fungicide application increased IPAR in both years, but RUE was only significantly reduced by disease in the first year, where mildew dominated the trial. The data were also used to estimate the coefficients of partitioning of dry matter to grains before and after anthesis. About 40% of dry matter produced before anthesis and about 60% after anthesis was estimated to contribute to grain yield. The low fraction after anthesis is probably due to the fact that it was not possible to estimate changes in RUE with time, which may lead to biases in the estimation of partitioning coefficients.

Relationship between light interception, ground cover and leaf area index in potatoes

1989 ◽  
Vol 113 (3) ◽  
pp. 355-359 ◽  
Author(s):  
D. M. Firman ◽  
E. J. Allen
Keyword(s):  
Leaf Area Index ◽  
Leaf Area ◽  
Dry Matter ◽  
Ground Cover ◽  
Field Studies ◽  
Incident Radiation ◽  
Light Interception ◽  
Area Index

SUMMARYIn field studies of two varieties in Cambridge, UK, in 1985 and 1986, the percentage of total incident radiation intercepted by potato canopies with complete ground cover was as low as 80% for some plots but approached 100% in dense canopies. Although percentage ground cover is useful for assessing canopy growth, it is not wholly suitable for estimating light interception and may lead to serious errors in calculation of efficiency of conversion into dry matter.

Sign in / Sign up

Export Citation Format

Share Document