Different methods for determining leaf area of some oil crops

1971 ◽  
Vol 77 (1) ◽  
pp. 19-24 ◽  
Author(s):  
Idris Mohmed Nur
Keyword(s):  
Leaf Area ◽  
Oil Crops ◽  
Area Estimate ◽  
Length Width ◽  
Width Factor

SummaryStudies of leaf area estimate of some oil crops were made using planimeter measurement, punch borer and length × width × factor. The extent of sample variation depended on the variety in each of these methods; the last two methods were found to be simple, precise and less time consuming.

scholarly journals Alometric Model for Estimation of Leaf Area of Garcinia brasiliensis Mart. Through Non-destructive Method

2019 ◽  
Vol 11 (10) ◽  
pp. 154
Author(s):  
Vinicius de Souza Oliveira ◽  
Cássio Francisco Moreira de Carvalho ◽  
Juliany Morosini França ◽  
Flávia Barreto Pinto ◽  
Karina Tiemi Hassuda dos Santos ◽  
...  
Keyword(s):  
Leaf Area ◽  
Linear Equations ◽  
Absolute Error ◽  
Coefficient Of Determination ◽  
Maximum Width ◽  
Linear Dimensions ◽  
Length Width ◽  
Independent Variable ◽  
The Mean ◽  
Non Destructive

The objective of the present study was to test and establish mathematical models to estimate the leaf area of Garcinia brasiliensis Mart. through linear dimensions of the length, width and product of both measurements. In this way, 500 leaves of trees with age between 4 and 6 years were collected from all the cardinal points of the plant in the municipality of São Mateus, North of the State of Espírito Santo, Brazil. The length (L) along the main midrib, the maximum width (W), the product of the length with the width (LW) and the observed leaf area (OLA) were obtained for all leaves. From these measurements were adjusted linear equations of first degree, quadratic and power, in which OLA was used as dependent variable as function of L, W and LW as independent variable. For the validation, the values of L, W and LW of 100 random leaves were substituted in the equations generated in the modeling, thus obtaining the estimated leaf area (ELA). The values of the means of ELA and OLA were tested by Student’s t test 5% of probability. The mean absolute error (MAE), root mean square error (RMSE) and Willmott’s index d for all proposed models were also determined. The choice of the best model was based on the non significant values in the comparison of the means of ELA and OLA, values of MAE and RMSE closer to zero and value of the index d and coefficient of determination (R2) close to unity. The equation that best estimates leaf area of Garcinia brasiliensis Mart. in a way non-destructive is the power model represented by por ELA = 0.7470(LW)0.9842 and R2 = 0.9949.

scholarly journals Models for estimating yacon leaf area

2016 ◽  
Vol 34 (3) ◽  
pp. 422-427 ◽  
Author(s):  
Wellington A Erlacher ◽  
Fábio L Oliveira ◽  
Gustavo S Fialho ◽  
Diego MN Silva ◽  
Arnaldo HO Carvalho
Keyword(s):  
Leaf Area ◽  
Crop Production ◽  
Scientific Information ◽  
Leaf Size ◽  
Leaf Length ◽  
Logarithmic Model ◽  
Area Estimate ◽  
Independent Variable ◽  
Precision And Accuracy ◽  
Non Destructive

ABSTRACT The recent exploration of yacon demands scientific information for improving the crop production technology. This study aimed to set a leaf area estimate model for yacon plants, using non-destructive measurements of leaf length (L) and/or width (W). Sixty-four representative yacon plants were randomly selected in an experimental field during the full vegetative growth. One thousand leaves of various sizes were taken from those plants for setting and validating a model. The logarithmic model best fitted this purpose, the result of multiplying length by width being used as independent variable. Yacon leaf area can be determined with high precision and accuracy by LALW = (-27.7418 + (3.9812LW / ln LW ) , disregarding the leaf size.

Components of seed mass and their relationships to seedling size in Calamovilfa longifolia

1993 ◽  
Vol 71 (4) ◽  
pp. 551-557 ◽  
Author(s):  
Jianhua Zhang ◽  
M. A. Maun
Keyword(s):  
Key Words ◽  
Leaf Area ◽  
Seed Mass ◽  
Seedling Size ◽  
Relative Contribution ◽  
Length Width ◽  
Seed Reserves ◽  
Calamovilfa Longifolia

Greenhouse studies were conducted to determine the relative contribution of endosperm and embryo masses to seed mass and seedling size in Calamovilfa longifolia. Seed mass in a sample varied from 0.71 to 3.17 mg per seed, and according to fitted functions, from approximately 0.26 to 2.48 mg per endosperm and from 0.15 to 0.50 mg per embryo. Both the embryo and endosperm masses were significantly correlated with mass, length, width, and area (length × width) of seeds. Seedling (2-weeks old) height, leaf area, and dry weights of leaves, stems, and roots were also highly positively correlated with seed mass. Because endosperm mass contributed much more to the variation in seed mass and showed stronger correlation with seed mass than embryo mass, seedling size may depend mainly on the amount of seed reserves in the endosperm rather than the embryo. Key words: seed mass, seedling size, embryo mass, endosperm mass, Calamovilfa longifolia.

scholarly journals Leaf area estimation of Burley tobacco

2021 ◽  
Vol 51 (1) ◽  
Author(s):  
Marcos Toebe ◽  
Francis Junior Soldateli ◽  
Rafael Rodrigues de Souza ◽  
Anderson Chuquel Mello ◽  
Alexandre Segatto
Keyword(s):  
Leaf Area ◽  
Tobacco Industry ◽  
Width Ratio ◽  
Area Estimation ◽  
Burley Tobacco ◽  
Linear Dimensions ◽  
Main Variable ◽  
Length Width ◽  
Tobacco Cultivar ◽  
Measured Length

ABSTRACT: Leaf area is an important growth variable in agricultural crops and the leaf is the main variable of interest in the tobacco industry. So, the aim of this scientific research was to estimate the Burley tobacco leaf area by linear dimensions of the leaves and to determine which mathematical model is more adequate for this purpose. Two experiments were carried out with Burley tobacco, cultivar DBH 2252, in 2016/2017 and 2018/2019 agricultural years, respectively, in the municipalities of Itaqui and Vanini - RS - Brazil. In 600 leaves were measured length (L), width (W), length×width product (LW), length/width ratio (L/W) and determined the real leaf area (LA). Four hundred and fifty leaves were separated to generate models of the leaf area as a function of linear dimension and the other 150 leaves were used for model’s validation. The power model LA = 0.5037LW1.04435 (R² = 0.9960) is the most adequate for Burley tobacco ‘DBH 2252’ leaf area estimation. Alternatively, the models LA=2.0369W1.8619 (R²=0.9796) and LA=0.1222L2.2771 (R²=0.9738) based on width and length, respectively, can be used when only one leaf dimension is measured.

scholarly journals A new empirical equation to describe the vertical leaf distribution profile of maize

2021 ◽  
pp. 1-11
Author(s):  
P. P. Fan ◽  
Y. Y. Li ◽  
J. B. Evers ◽  
B. Ming ◽  
C. X. Wang ◽  
...  
Keyword(s):  
Leaf Area ◽  
Empirical Equation ◽  
Leaf Length ◽  
Maize Hybrids ◽  
Vertical Leaf ◽  
Maximum Value ◽  
Modern Maize ◽  
Length Width ◽  
New Equation ◽  
Leaf Distribution

Abstract The characteristic traits of maize (Zea mays L.) leaves affect light interception and photosynthesis. Measurement or estimation of individual leaf area has been described using discontinuous equations or bell-shaped functions. However, new maize hybrids show different canopy architecture, such as leaf angle in modern maize which is more upright and ear leaf and adjacent leaves which are longer than older hybrids. The original equations and their parameters, which have been used for older maize hybrids and grown at low plant densities, will not accurately represent modern hybrids. Therefore, the aim of this paper was to develop a new empirical equation that captures vertical leaf distribution. To characterize the vertical leaf profile, we conducted a field experiment in Jilin province, Northeast China from 2015 to 2018. Our new equation for the vertical distribution of leaf profile describes leaf length, width or leaf area as a function of leaf rank, using parameters for the maximum value for leaf length, width or area, the leaf rank at which the maximum value is obtained, and the width of the curve. It thus involves one parameter less than the previously used equations. By analysing the characteristics of this new equation, we identified four key leaf ranks (4, 8, 14 and 20) for which leaf parameter values need to be quantified in order to have a good estimation of leaf length, width and area. Together, the method of leaf area estimation proposed here adds versatility for use in modern maize hybrids and simplifies the field measurements by using the four key leaf ranks to estimate vertical leaf distribution in maize canopy instead of all leaf ranks.

scholarly journals Leaf area estimatites of custard apple tree progenies

2004 ◽  
Vol 26 (3) ◽  
pp. 558-560 ◽  
Author(s):  
Paulo Sérgio Lima e Silva ◽  
Decio Barbin ◽  
Ranoel José de Sousa Gonçalves ◽  
João Domingos da Cruz Firmino ◽  
Idaiane Costa Fonseca
Keyword(s):  
Leaf Area ◽  
Apple Tree ◽  
Leaf Length ◽  
Regression Equations ◽  
Measuring Device ◽  
Mature Leaves ◽  
Custard Apple ◽  
Length Width ◽  
Leaf Dimensions ◽  
Automatic Measuring Device

Leaf area measurements are required in several agronomical studies. Usually, there is an interest for measurement methods that are simple, quick and that will not destroy the leaf. The objectives of this work were to evaluate leaf area (y), length (l) and width (w) of 20 half-sibling progenies of custard apple tree (Annona squamosa L.), and to fit regression equations of the type y = a + bx, where x = l.w, that will allow y to be estimated based on l and w. The experiment was conducted as random blocks with five replicates and four plants per plot. Five mature leaves were randomly collected from each plant. Leaf area was measured with an automatic measuring device and leaf dimensions were determined with a ruler. All values of b were different from zero. Differences occurred only in 11% of the 190 possible comparison pairs between progenies, with regard to the estimates of b. No differences were observed between progenies with respect to leaf length, width and area. In view of this fact, the equation y = 0.72 x (R² = 0.77) was fitted for all progenies.

scholarly journals Leaf Area Estimate of Erythroxylum simonis Plowman by Linear Dimensions

2018 ◽  
Vol 25 (2) ◽  
Author(s):  
João Everthon da Silva Ribeiro ◽  
Ana Jéssica Soares Barbosa ◽  
Manoel Bandeira de Albuquerque
Keyword(s):  
Leaf Area ◽  
Linear Dimensions ◽  
Area Estimate

scholarly journals Leaf area estimation of Anacardium humile

2020 ◽  
Vol 42 (5) ◽  
Author(s):  
Francielly Rodrigues Gomes ◽  
Danielle Fabíola Pereira da Silva ◽  
Angelita Lorrayne Soares Lima Ragagnin ◽  
Pedro Henrique Magalhães de Souza ◽  
Simério Carlos Silva Cruz
Keyword(s):  
Image Analysis ◽  
Leaf Area ◽  
Descriptive Analysis ◽  
Leaf Disc ◽  
Fresh Weight ◽  
Linear Measurements ◽  
Productive Potential ◽  
Length Width ◽  
Basal Portion ◽  
The Relationship

Abstract The Anacardium humile A. St.- Hil. fruit tree has productive potential, being their fruits appreciated in the Cerrado region for having characteristic flavor, however, this species is still exploited in an extractive way, being necessary studies for its domestication. The aim of this work was to estimate the leaf area of Anacardium humile. One hundred leaves were collected in the biological collection from a genetic resources field and evaluated for length, width and fresh weight, and scanned at resolution of 300 dpi to determine the leaf area with the aid of the ImageJ image analysis program. Subsequently, a leaf disc with a diameter of 22.27 mm was detached at the basal portion of each leaf, in which the fresh weight of the discs was obtained. Data were submitted to descriptive analysis and the relationship among the features explained by Pearson’s correlation with the software Rbio. The data were also subjected to regression analysis to explain the relationship between leaf area and measurements of width, length and leaf weight, and to fit the proper statistical model with the software Origin. It was concluded that leaf area can be determined by image analysis software and linear measurements are correlated to leaf area.

scholarly journals Chilling Effects on Shoot Emergence and Subsequent Growth in Hosta

1999 ◽  
Vol 17 (2) ◽  
pp. 84-87
Author(s):  
Gary J. Keever ◽  
Mark S. West ◽  
J. Raymond Kessler
Keyword(s):  
Leaf Area Index ◽  
Leaf Area ◽  
Dry Weight ◽  
Emergence Time ◽  
Subsequent Growth ◽  
Area Index ◽  
Shoot Dry Weight ◽  
Length Width ◽  
Shoot Emergence

Abstract Two hosta cultivars, ‘Francee’ and ‘Frances Williams’, were chilled for 0 to 16 weeks at 4C (39F) prior to forcing in a heated greenhouse. As chilling duration increased, times to shoot emergence and first unfurled leaf and days gained in shoot emergence time per day of chilling decreased at a decreasing rate, leaf area index (length × width) of the first unfurled leaf increased at a decreasing rate and shoot dry weight increased linearly. Shoots of non-chilled plants of ‘Francee’ emerged an average of 32 days before those of ‘Frances Williams’. In ‘Francee’ chilled for 0 and 2 weeks, 30% and 10% of plants, respectively, failed to emerge shoots and 60% and 10% failed to unfurl a leaf. In ‘Frances Williams’ chilled for 0, 2 and 4 weeks, 60%, 30% and 50% of plants, respectively, failed to emerge shoots and 80%, 30% and 50% failed to unfurl a leaf. All plants of both cultivars chilled for longer durations emerged shoots and unfurled at least one leaf.

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