Vision-Based Measurement of Leaf Dimensions and Area Using a Smartphone

2021 ◽  
pp. 277-290
Author(s):  
Chanh-Nghiem Nguyen ◽  
Dang-Khoa Thach ◽  
Quoc-Thang Phan ◽  
Chi-Ngon Nguyen
Keyword(s):  
Leaf Dimensions

scholarly journals Estimation of leaf area of Erythroxylum citrifolium from linear leaf dimensions

2019 ◽  
Vol 35 (6) ◽  
Author(s):  
João Everthon da Silva Ribeiro ◽  
Ester dos Santos Coêlho ◽  
Francisco Romário Andrade Figueiredo ◽  
Sérgio de Faria Lopes ◽  
Manoel Bandeira de Albuquerque
Keyword(s):  
Leaf Area ◽  
Leaf Blade ◽  
Information Criterion ◽  
Coefficient Of Determination ◽  
Concordance Index ◽  
R And D ◽  
Linear Dimensions ◽  
Bias Index ◽  
Linear Leaf ◽  
Leaf Dimensions

Erythroxylum citrifolium is a neotropical plant species recorded in all regions of Brazil. Determining leaf area is of fundamental importance to studies related to plant propagation and growth. The objective was to obtain an equation to estimate the leaf area of E. citrifolium from linear dimensions of the leaf blade (length and width). A total of 200 leaf blades were collected in Parque Estadual Mata do Pau-Ferro in the municipality of Areia, state of Paraíba, Northeast Brazil. The models evaluated were: linear, linear without intercept, quadratic, cubic, power and exponential. The best model was determined by the criteria of: high coefficient of determination (R²), low root mean square error (RMSE), low Akaike information criterion (AIC), high Willmott concordance index (d) and a BIAS index close to zero. All of the models constructed satisfactorily estimated the leaf area of E. citrifolium, with coefficients of determination above 0.9050, but the power model using the product between length and width (L*W) ŷ = 0.5966 * LW1.0181 was the best, with the highest values of R² and d, low values of RMSE and AIC, and a BIAS index closest to zero.

scholarly journals Non-destructive linear model for leaf area estimation in Vernonia ferruginea Less

2015 ◽  
Vol 75 (1) ◽  
pp. 152-156 ◽  
Author(s):  
MC. Souza ◽  
CL. Amaral
Keyword(s):  
Linear Regression ◽  
Leaf Area ◽  
Leaf Development ◽  
Linear Equations ◽  
Accurate Estimate ◽  
Area Estimation ◽  
Leaf Dimensions ◽  
Non Destructive ◽  
Linear Regressions ◽  
Very High

Leaf area estimation is an important biometrical trait for evaluating leaf development and plant growth in field and pot experiments. We developed a non-destructive model to estimate the leaf area (LA) of Vernonia ferruginea using the length (L) and width (W) leaf dimensions. Different combinations of linear equations were obtained from L, L2, W, W2, LW and L2W2. The linear regressions using the product of LW dimensions were more efficient to estimate the LA of V. ferruginea than models based on a single dimension (L, W, L2 or W2). Therefore, the linear regression “LA=0.463+0.676WL” provided the most accurate estimate of V. ferruginea leaf area. Validation of the selected model showed that the correlation between real measured leaf area and estimated leaf area was very high.

Breeding System, Karyotype and Variation Within and Between Populations of Rutidosis leptorrhynchoides F Muell (Asteraceae, Inuleae)

1991 ◽  
Vol 39 (1) ◽  
pp. 85 ◽  
Author(s):  
P Leeton ◽  
YJ Fripp
Keyword(s):  
Chromosome Number ◽  
Breeding System ◽  
Geographic Distance ◽  
Endangered Plant ◽  
Allozyme Analysis ◽  
Self Incompatibility ◽  
Eastern Australia ◽  
Incompatibility System ◽  
Leaf Dimensions ◽  
Allozyme Loci

The endangered plant species, Rutidosis leptorrhynchoides (button wrinklewort), is now known from only a few populations in each of two regions separated by approximately 500 km in south-eastern Australia. Plants were examined from several populations from each region. No differences in chromosome number or morphology were observed among plants or populations. All counts were diploid, 2n = 26. Viable progeny were obtained following self-pollination and allozyme analysis indicated that these progeny were the result of selfing and not agamospermy. This species is not an obligate outcrosser and does not have a classical pre-zygotic self-incompatibility system. However, outcross pollen may have an advantage over self pollen and this species may thus be preferentially outcrossing. The pollen: ovule ratios (mean 3186 ± 48.5) were consistent with this hypothesis. Allele frequencies at allozyme loci diferred little between populations, with an estimated 97% of the variation within populations. There was no correlation between genetic distance and geographic distance. In contrast, for the leaf dimensions of plants germinated and raised together in a glasshouse there were differences between plants from the two regions. It is recommended that populations from both regions should be conserved.

Effects of photoperiod on leaf appearance rate and leaf dimensions in winter and spring wheats

1996 ◽  
Vol 76 (1) ◽  
pp. 43-50 ◽  
Author(s):  
S. Pararajasingham ◽  
L. A. Hunt
Keyword(s):  
Leaf Area ◽  
Leaf Length ◽  
Leaf Number ◽  
Dry Matter Accumulation ◽  
Flag Leaves ◽  
Appearance Rate ◽  
Rate Of Increase ◽  
Leaf Appearance Rate ◽  
Leaf Dimensions ◽  
Leaf Appearance

Research on genotypic variation in the response of leaf-area production and expansion to photoperiod in wheat is limited. Growth-cabinet experiments using four spring and four winter wheat (Triticum aestivum L.) cultivars and four photoperiod (8, 12, 16 and 20 h) treatments were thus conducted with the objective of investigating the effect of photoperiod on leaf appearance rate and leaf dimensions. Winter wheats were grown without vernalization. In the spring wheats, flag leaves and spikes were formed under the longer photoperiod (16 and 20 h) treatments, and leaf number increased linearly with time. At the shorter photoperiods, flag leaves and spikes appeared in some cultivars only, and the rate of increase in leaf number decreased in the later stages. Final leaf number was greater at shorter photoperiods. In the winter cultivars, more leaves appeared than in the spring types under the longer photoperiods. For leaves 3–7, leaf number was a linear function of time, with photoperiod and cultivar effects. For one of four spring cultivars, the rate of leaf appearance was greater at 8 h than at 20 h, whereas for three of the winter cultivars the reverse was true. Leaf length increased with leaf number up to at least nodes 5–6 for both spring and winter types but decreased for the later-formed leaves for the spring but not for the winter types. Leaves of plants grown under photoperiods longer than 8 h were longer and broader than those grown under the short photoperiod, and the effect was more pronounced in winter than in spring cultivars. Such genotypic differences in the direct effects of photoperiod on leaf dimensions, which could influence the rates of leaf-area production and dry-matter accumulation under field conditions, emphasize that future studies should incorporate genotypes from different eco-physiological regions and that simulation models of wheat growth and development may need to account for variability in the control of vegetative growth. Key words: Wheat, photoperiod, leaf appearance rate, leaf length, leaf width

scholarly journals Estimation of buckwheat leaf area by leaf dimensions

2021 ◽  
Vol 42 (3Supl1) ◽  
pp. 1529-1548
Author(s):  
Alberto Cargnelutti Filho ◽  
◽  
Rafael Vieira Pezzini ◽  
Ismael Mario Márcio Neu ◽  
Gabriel Elias Dumke ◽  
...  
Keyword(s):  
Leaf Area ◽  
Linear Model ◽  
Leaf Blade ◽  
Sowing Date ◽  
Quadratic Model ◽  
Digital Photo ◽  
Sowing Dates ◽  
Leaf Dimensions ◽  
Fagopyrum Esculentum Moench ◽  
Uniformity Trials

The objective of this work was to model and identify the best models for estimating the leaf area, determined by digital photos, of buckwheat (Fagopyrum esculentum Moench) of the cultivars IPR91-Baili and IPR92-Altar, as a function of length (L), width (W) or length x width product (LW) of the leaf blade. Ten uniformity trials (blank experiments) were carried out, five with IPR91-Baili cultivar and five with IPR92-Altar cultivar. The trials were performed on five sowing dates. In each trial and cultivar, expanded leaves were collected at random from the lower, middle and upper segments of the plants, totaling 1,815 leaves. In these 1,815 leaves, L and W were measured and the LW of the leaf blade was calculated, which were used as independent variables in the model. The leaf area of each leaf was determined using the digital photo method (Y), which was used as a dependent variable of the model. For each sowing date, cultivar and thirds of the plant, 80% of the leaves (1,452 leaves) were randomly separated for the generation of the models and 20% of the leaves (363 leaves) for the validation of the models of leaf area estimation as a function of linear dimensions. For buckwheat, IPR91-Baili and IPR92-Altar cultivars, the quadratic model (Ŷ = 0.5217 + 0.6581LW + 0.0004LW2, R2 = 0.9590), power model (Ŷ = 0.6809LW1.0037, R2 = 0.9587), linear model (Ŷ = 0.0653 + 0.6892LW, R2 = 0.9587) and linear model without intercept (Ŷ = 0.6907LW, R2 = 0.9587) are indicated for the estimation of leaf area determined by digital photos (Y) based on the LW of the leaf blade (x), and, preferably, the linear model without intercept can be used, due to its greater simplicity.

scholarly journals Physical and Chemical Characteristics of Pomegranates

HortScience ◽  
2005 ◽  
Vol 40 (5) ◽  
pp. 1200-1203 ◽  
Author(s):  
Pavlina D. Drogoudi ◽  
Constantinos Tsipouridis ◽  
Zisis Michailidis
Keyword(s):  
Antioxidant Activity ◽  
Ascorbic Acid ◽  
Total Phenolic ◽  
Chemical Characteristics ◽  
Total Anthocyanin ◽  
Physical And Chemical Characteristics ◽  
Red Color ◽  
Hue Angle ◽  
Leaf Dimensions ◽  
Physical And Chemical

Twenty pomegranate (Punica granatum L.) accessions were collected from different regions in northern Greece and evaluated under uniform conditions for leaf dimensions, frost resistance, and fruit physical and chemical characteristics, such as the juice antioxidant activity [ascorbate equivalent antioxidant activity (AEAC)], using the radical DPPH, ascorbic acid, total phenolic and total anthocyanin contents. Considerable variation in the characteristics studied was found and valuable pomological traits were exhibited. Cluster analysis produced cases of homonymy between some accessions. Principal component analyses showed that the component explaining the greatest variability positively correlated with percent juice, fruit chroma, AEAC, total anthocyanins, and soluble solids content (SSC), but negatively correlated with fruit fresh weight (FW), fruit and seed hue angle (less red color), total acidity, and leaf dimensions. Fruit size was positively correlated with acidity, while acidity was negatively correlated with SSC. Skin thickness and FW were correlated with fruit hue angle and chroma, suggesting that red color may better develop in thick-skinned and/or small-sized pomegranates. Total anthocyanin content was negatively correlated with FW and fruit hue angle. AEAC was positively correlated with total anthocyanin and ascorbic acid contents, the latter one constituted a 15% contribution to AEAC. The associations found among physical and chemical traits suggest that consumers interested in a healthier produce should be directed to small and red pomegranates.

scholarly journals Sent to the Corner: xylem vessel anatomy not surface area determines megaphyll hydraulics in Cecropia obtusa Trécul (Urticaceae)

2018 ◽  
Author(s):  
Sébastien Levionnois ◽  
Sabrina Coste ◽  
Eric Nicolini ◽  
Clément Stahl ◽  
Hélène Morel ◽  
...  
Keyword(s):  
Cross Sections ◽  
Specific Conductivity ◽  
Secondary Growth ◽  
Cross Sectional ◽  
Positive Correlation ◽  
Leaf Level ◽  
Leaf Dimensions ◽  
Level Model ◽  
Primary Stem ◽  
Leaf Model

AbstractCorners rule predicts a positive correlation between leaf dimensions and the cross-sectional area of the primary stem. Although this relationship is usually explained by hydraulic and mechanical requirements, these hypotheses have never been tested empirically. However, Corner’s rule is tricky to investigate since rapid secondary growth of the stem prevents a rigorous link being established between a given leaf and the supporting stem. We chose a twig-like leaf model since petiole anatomy is only linked to the attached lamina. We tested the hypothesis that anatomical adjustments to hydraulic requirements related to vessel size enable reduced investment in tissue in the framework of Corner’s rule. We conducted a functional, mechanistic and intraspecific investigation of Cecropia obtusa Trécul, a Neotropical pioneer tree, by integrating morphological, anatomical and theoretical hydraulic traits around the lamina-petiole size relationship. The twig-like structure of the leaf and the strong lamina-petiole correlation of this model tree species made it possible to use the leaf-level model for a rigorous investigation of the functional implications of Corner’s rule. We found a positive correlation between petiole size, lamina size, the ratio of mean vessel area to vessel frequency in the petiole xylem and theoretical specific conductivity in the petiole xylem. Hydraulic function supports Corner’s rule to a lesser extent than previously thought. Variations in vessel dimensions mainly drive xylem hydraulic performances and avoid disproportionate petiole cross-sections to answer to hydraulic requirements associated with lamina size.

scholarly journals The use of numerical methods in the design of a formula that returns the surface of the leaves of Phragmites australis (Cav.) Trin. Ex Steud.

2020 ◽  
Vol 20 (1) ◽  
pp. 33-39
Author(s):  
Katarzyna Krzyżanowska ◽  
Paweł Krzyżanowski
Keyword(s):  
Linear Regression ◽  
Phragmites Australis ◽  
Measurement Errors ◽  
Numerical Models ◽  
Common Reed ◽  
Small Samples ◽  
Real Surface ◽  
Maximum Width ◽  
Average Accuracy ◽  
Leaf Dimensions

AbstractThe paper presents the results of calculations and a verification of numerical models developed for estimating the surface of leaves of the common reed (Phragmites australis (Cav.) Trin. Ex Steud.). The research sample consisted of 137 leaves collected from the rush zone of Lake Raduńskie Górne in 2018. The total area of leaves obtained for testing was 1932.3 cm2. To derive a formula that returns the surface of common reed foliage regression models were used – MLR (Multiple Linear Regression) and SLR (Stepwise Linear Regression). It has been shown that the measurement of basic leaf dimensions (i.e. length – L, mid-width – WM and maximum width – WX) makes it possible to define an empirical formula which, with an average accuracy of 99.9%, allows the real surface of leaves to be estimated. The modelling results were compared with formulas currently used in practice, and the measurement errors were determined using these formulas. It has been shown that the formulas used to date are subject to RMSE to the value of 1.19-2.52. The application of the developed formula (A = 0.4486 – 0.046 L + 7.9267 WM – 5.8121 WX + 0.5853 L • WX) will significantly reduce errors in leaf surface estimation (RMSE = 0.86) and thus the amount of reed transpiration and evapotranspiration, especially in the case of handling small samples (number of leaves and measurements).

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