scholarly journals A new method for estimating the leaf area index of cucumber and tomato plants

2003 ◽  
Vol 21 (4) ◽  
pp. 666-669 ◽  
Author(s):  
Flávio Favaro Blanco ◽  
Marcos Vinícius Folegatti
Keyword(s):  
Leaf Area Index ◽  
Leaf Area ◽  
Area Measurement ◽  
Quadratic Model ◽  
Regression Equations ◽  
Area Index ◽  
Tomato Plants ◽  
Potted Plants ◽  
Growing Period ◽  
Area Distribution

Non-destructive methods of leaf area measurement are useful for small plant populations, such as experiments with potted plants, and allow the measurement of the same plant several times during the growing period. A methodology was developed to estimate the leaf area index (LAI) of cucumber and tomato plants through the evaluation of the leaf area distribution pattern (LADP) of the plants and the relative height of the leaves in the plants. Plant and leaf height, as well as the length and width of all leaves were measured and the area of some leaves was determined by a digital area meter. The obtained regression equations were used to estimate the leaf area for all relative heights along the plant. The LADP adjusted to a quadratic model for both crops and LAI were estimated by measuring the length and width of the leaves located at the relative heights representing the mean leaf area of the plants. The LAI estimations presented high precision and accuracy when the proposed methodology was used resulting in time and effort savings and being useful for both crops.

scholarly journals DESENVOLVIMENTO DO TOMATEIRO INDUSTRIAL EM RESPOSTA A DIFERENTES NÍVEIS DE IRRIGAÇÃO

Irriga ◽  
2020 ◽  
Vol 25 (3) ◽  
pp. 432-448
Author(s):  
Cícero José da Silva ◽  
José Antônio Frizzone ◽  
César Antônio da Silva ◽  
Nadson de Carvalho Pontes ◽  
Luiz Felipe Mariano da Silva ◽  
...  
Keyword(s):  
Leaf Area Index ◽  
Leaf Area ◽  
Plant Development ◽  
Tomato Plant ◽  
Dry Mass ◽  
Area Index ◽  
Tomato Plants ◽  
Subsurface Drip ◽  
Irrigation Levels ◽  
E Mail

DESENVOLVIMENTO DO TOMATEIRO INDUSTRIAL EM RESPOSTA A DIFERENTES NÍVEIS DE IRRIGAÇÃO     Cícero José da Silva1; José Antônio Frizzone2; César Antônio da Silva3; Nadson de Carvalho Pontes4; Luiz Felipe Mariano da Silva5 E Ênio Eduardo Basílio6   1Professor do Curso Bacharelado em Agronomia, Instituto Federal Goiano – Campus Morrinhos – GO, BR 153, Km 633, Zonal Rural, CEP;75650-000, Morrinhos – GO, Brasil. E-mail: [email protected] 2Professor Aposentado Colaborador Senior, Departamento de Engenharia de Biossitemas, Escola Superior de Agricultura “Luiz de Queiroz” – Universidade de São Paulo, Avenida Pádua Dias, N 11, Caixa Postal 9, CEP: 13418-900, Piracicaba – SP, Brasil. E-mail: [email protected] 3Professor do Curso Bacharelado em Agronomia, Instituto Federal Goiano – Campus Morrinhos – GO, BR 153, Km 633, Zonal Rural, CEP;75650-000, Morrinhos – GO, Brasil. E-mail: [email protected] 4Professor do Curso Bacharelado em Agronomia, Instituto Federal Goiano – Campus Morrinhos – GO, BR 153, Km 633, Zonal Rural, CEP;75650-000, Morrinhos – GO, Brasil. E-mail: [email protected] 5Estudante de Iniciação Científica do Curso Bacharelado em Agronomia, Instituto Federal Goiano – Campus Morrinhos – GO, BR 153, Km 633, Zonal Rural, CEP;75650-000, Morrinhos – GO, Brasil. E-mail: [email protected] 6Técnico Administrativo, Mestre em Olericultura, Instituto Federal Goiano – Campus Morrinhos – GO, BR 153, Km 633, Zonal Rural, CEP;75650-000, Morrinhos – GO, Brasil. E-mail: [email protected]     1 RESUMO   O objetivo desta pesquisa foi avaliar o desenvolvimento de plantas de tomateiros submetidas a diferentes níveis de reposição da irrigação, aplicados via sistema gotejamento subsuperficial durante duas safras. O experimento foi conduzido no delineamento em blocos ao acaso, com quatro repetições. Foram avaliados cinco níveis de irrigação: 50, 75, 100, 125 e 150% da evapotranspiração da cultura (%ETc) medida com lisímetros de pesagem, sobre o desenvolvimento de plantas de tomateiro. Cada parcela experimental foi composta por três fileiras de plantas de 5,5 m de comprimento, espaçadas a 1,10 m entre si e 0,30 m entre plantas. As avaliações de área foliar, índice de área foliar, massa seca de raiz, caule, folhas, flores, frutos e total foram realizadas aos 45, 65 e 85 dias após o transplante das mudas. Irrigações deficitárias e em excesso prejudicaram o desenvolvimento vegetativo das plantas de tomateiro. Os maiores valores de área foliar, índice de área foliar e massa seca total das plantas de tomateiro foram estimados com níveis de irrigação que variaram de 96 a 112% da ETc, variando de acordo com o ano de avaliação e a fase de desenvolvimento do tomateiro. Irrigações deficitárias e excessivas prejudicaram a floração e frutificação do tomateiro híbrido BRS Sena.             Palavras-chave: Solanum lycopersicom L.; gotejamento enterrado; manejo da irrigação; massa seca.             Silva, c. j. da; FRIZZONE, J. A.; SILVA, C. A. da; pontes, n. de C.; SILVA, L. F. M. da; BASÍLIO, Ê. E. Industrial tomato plant development in response to different irrigation levels    2 ABSTRACT   This research aimed to evaluate tomato plant development submitted to different irrigation replacement levels, irrigated via subsurface drip system for two harvests. The experiment was conducted under a randomized complete block design with four replications. Five irrigation levels were evaluated: 50, 75, 100, 125 and 150% of crop evapotranspiration (% ETc) measured with weighing lysimeters over the tomato plants development. Each experimental plot was composed of three plants rows with 5.5 m long, spaced 1.10 m apart and 0.30 m between plants. Leaf area, leaf area index, root dry matter, stem, leaves, flowers, fruits and total were evaluated at 45, 65 and 85 days after seedlings transplanting. Deficit and excess irrigation impaired the vegetative development of tomato plants. The highest values of leaf area, leaf area index and plants total dry mass were estimated with irrigation levels ranging from 96 to 112% of ETc, depending on the evaluation harvest year and the crop development phase. Deficit and excessive irrigation affected the flowering and fruiting of the hybrid tomato BRS Sena.   Keywords: Solanum lycopersicom L; subsurface drip irrigation; irrigation manegement; dry mass.

Estimating leaf area index and light extinction coefficients in stands of Douglas-fir (Pseudotsugamenziesii)

1993 ◽  
Vol 23 (2) ◽  
pp. 317-321 ◽  
Author(s):  
Nicholas J. Smith
Keyword(s):  
Leaf Area Index ◽  
Leaf Area ◽  
Extinction Coefficient ◽  
Photosynthetically Active Radiation ◽  
Douglas Fir ◽  
Regression Equations ◽  
Individual Tree ◽  
Area Index ◽  
Active Radiation ◽  
Wide Range

Both photosynthetically active radiation penetrating the overstory canopy and overstory leaf area index were determined in forty-three 12 × 12 m plots in even-aged Douglas-fir (Pseudotsugamenziesii (Mirb.) Franco) stands. Stands were located on the east side of Vancouver Island, British Columbia, between 300 and 800 m on flat to south-facing slopes and were from a wide range of stem densities and stocking levels. In nine core plots total tree leaf area index was estimated using regression equations from individual-tree stem diameter and stand relative density. A single extinction coefficient did not govern the attenuation of photosynthetically active radiation with respect to leaf area index. For a given leaf area index, the extinction coefficient was smaller at low relative densities because of the presence of canopy gaps. Light attenuation models assuming a single extinction coefficient seriously underpredict stand leaf area index, especially at low stand densities. A modified Beer's Law model was used to predict light penetration, which implicitly accounted for foliage clumping.

Vertical leaf area distribution, light transmittance, and application of the Beer–Lambert Law in four mature hardwood stands in the southern Appalachians

1995 ◽  
Vol 25 (6) ◽  
pp. 1036-1043 ◽  
Author(s):  
James M. Vose ◽  
Barton D. Clinton ◽  
Neal H. Sullivan ◽  
Paul V. Bolstad
Keyword(s):  
Leaf Area Index ◽  
Leaf Area ◽  
Independent Set ◽  
Light Transmittance ◽  
Litter Fall ◽  
Validation Data ◽  
Area Index ◽  
Vertical Leaf ◽  
Area Distribution ◽  
Leaf Area Distribution

We quantified stand leaf area index and vertical leaf area distribution, and developed canopy extinction coefficients (k), in four mature hardwood stands. Leaf area index, calculated from litter fall and specific leaf area (c2•g−1), ranged from 4.3 to 5.4 m2•m−2. In three of the four stands, leaf area was distributed in the upper canopy. In the other stand, leaf area was uniformly distributed throughout the canopy. Variation in vertical leaf area distribution was related to the size and density of upper and lower canopy trees. Light transmittance through the canopies followed the Beer–Lambert Law, and k values ranged from 0.53 to 0.67. Application of these k values to an independent set of five hardwood stands with validation data for light transmittance and litter-fall leaf area index yielded variable results. For example, at k = 0.53, calculated leaf area index was within ± 10% of litter-fall estimates for three of the five sites, but from −35 to + 85% different for two other sites. Averaged across all validation sites, litter-fall leaf area index and Beer-Lambert leaf area index predictions were in much closer agreement ( ± 7 to ± 15%).

Specific leaf area and leaf area index distribution in a young Douglas-fir plantation

1986 ◽  
Vol 16 (6) ◽  
pp. 1283-1288 ◽  
Author(s):  
M. Borghetti ◽  
G. G. Vendramin ◽  
R. Giannini
Keyword(s):  
Leaf Area Index ◽  
Leaf Area ◽  
Specific Leaf Area ◽  
Leaf Age ◽  
Douglas Fir ◽  
Leaf Biomass ◽  
Normal Curve ◽  
Area Index ◽  
Area Distribution ◽  
Leaf Area Distribution

The spatial distribution of specific leaf area and leaf area index of needles in different age classes has been investigated in a young and unthinned Douglas-fir (Pseudotsugamenziesii (Mirb.) Franco) plantation in Central Italy through the destructive analysis of 12 trees sampled in four diameter size classes. Specific leaf area decreased with leaf age and from crown base to apex. A clear interaction between the effects of age and position on specific leaf area was demonstrated. For the whole canopy the vertical distribution of leaf area was well fitted by a normal curve equation, which explained 97% of the variation. The midpoint of the leaf area distribution, estimated as a parameter of the normal curve, was found to be 1.2 m below the mean canopy depth. The standard deviation of leaf area with respect to height was 16.4%. The midpoint of leaf area distribution decreased as leaf age increased and increased as diameter size class increased. Strong and significant linear relationships were found between leaf biomass, leaf area, sapwood area, and diameter at breast height.

Effects of treated municipal wastewater on fluctuation trend of leaf area index and quality of maize (Zea mays)

2013 ◽  
Vol 67 (4) ◽  
pp. 797-802 ◽  
Author(s):  
Sayed Roholla Mousavi ◽  
Mohammad Galavi ◽  
Hamdollah Eskandari
Keyword(s):  
Zea Mays ◽  
Leaf Area Index ◽  
Leaf Area ◽  
Municipal Wastewater ◽  
Clean Water ◽  
Area Index ◽  
Growing Period ◽  
Significant Difference ◽  
Treated Municipal Wastewater

The effect of primary-treated municipal wastewater (TMWW) on the leaf area index (LAI) and quality of maize (Zea mays) was studied in comparison to the clean irrigation water (control). The experiment was based on a randomized block design with four replicates, and it was conducted in a field experiment in Aligoudarz (Iran). Irrigation was applied with five different methods as treatments: T1: irrigation with clean water during whole growing period (control); T2: 75% clean water and 25% TMWW; T3: 50% clean water and 50% TMWW; T4: 25% clean water and 75% TMWW; T5: irrigation with TMWW during whole growing period. Results showed that irrigation with TMWW had a significant positive impact on all characters compared with the control. Maximum LAI was yielded on the 80th day after emergence in T4. Use of TMWW increased seed oil to 5.85%, which was 29.2% more than that in the control. Maximum values for percentage of protein, total dry matter and phosphorus concentration were obtained in T5. Maximum zinc concentration (15.93 mg kg−1) was obtained in T4; it was 8% more than the control. According to the results there was no significant difference in treatment T4 and T5.

Biomass and leaf-area index maps derived from SPOT images for Toolik Lake and Imnavait Creek areas, Alaska

Polar Record ◽  
1995 ◽  
Vol 31 (177) ◽  
pp. 147-154 ◽  
Author(s):  
Margaret M. Shippert ◽  
Donald A. Walker ◽  
Nancy A. Auerbach ◽  
Brad E. Lewis
Keyword(s):  
Leaf Area Index ◽  
Leaf Area ◽  
Vegetation Index ◽  
Near Infrared ◽  
Normalized Difference Vegetation Index ◽  
Spatial Scales ◽  
Regression Equations ◽  
Area Index ◽  
Tundra Ecosystem ◽  
Toolik Lake

AbstractA new emphasis on understanding natural systems at large spatial scales has led to an interest in deriving ecological variables from satellite reflectance images. The normalized difference vegetation index (NDVI) is a measure of canopy greenness that can be derived from reflectances at near-infrared and red wavelengths. For this study we investigated the relationships between NDVI and leaf-area index (LAI), intercepted photosynthetically active radiation (IPAR), and biomass in an Arctic tundra ecosystem. Reflectance spectra from a portable field spectrometer, LAI, IPAR, and biomass data were collected for 180 vegetation samples near Toolik Lake and Imnavait Creek, Alaska, during July and August 1993. NDVI values were calculated from red and near-infrared reflectances of the field spectrometer spectra. Strong linear relationships are seen between mean NDVI for major vegetation categories and mean LAI and biomass. The relationship between mean NDVI and mean IPAR for these categories is not significant. Average NDVI values for major vegetation categories calculated from a SPOT image of the study area were found to be highly linearly correlated to average field NDVI measurements for the same categories. This indicates that in this case it is appropriate to apply equations derived for field-based NDVI measurements to NDVI images. Using the regression equations for those relationships, biomass and LAI images were calculated from the SPOT NDVI image. The resulting images show expected trends in LAI and biomass across the landscape.

scholarly journals Leaf area index assessment for tomato and cucumber growing period under different water treatments

2017 ◽  
Vol 63 (No. 10) ◽  
pp. 461-467 ◽  
Author(s):  
Hossain Shaikh Abdullah Al Mamun ◽  
Wang Lixue ◽  
Chen Taotao ◽  
Li Zhenhua
Keyword(s):  
Leaf Area Index ◽  
Leaf Area ◽  
North China ◽  
Block Design ◽  
Area Index ◽  
Water Capacity ◽  
Growing Period ◽  
Randomized Block Design ◽  
Best Fitting ◽  
Water Treatments

The aim of this study was to assess the leaf area index (LAI) of tomato and cucumber using an AccuPAR-LP-80-ceptometer to find the influence of irrigation. LAI was also determined by destructive sampling for comparison. The research was conducted at the Liaoning Water Conservancy Institute, North China in 2016. A randomized block design was used to test the influence of four treatments corresponding to field water capacity. Full irrigation (W<sub>1.0</sub>), 15% (W<sub>0.85</sub>), 25% (W<sub>0.75</sub>) and 35% (W<sub>0.65</sub>) water deficit were applied using the drip system. Regression model was developed to estimate LAI in response to irrigation. The results show that there is no difference between the two methods. The highest LAI obtained for tomato and cucumber was 5.21 and 3.21 m<sup>2</sup>/m<sup>2</sup>, respectively, with W<sub>0.85</sub> at 70-days after transplanting, which corresponds with destructive results. This result was found 11% higher and equal compared with W<sub>1.0</sub> for tomato (4.62) and cucumber (3.21), respectively. For both crops, LAI was found significantly influenced at 50-days after transplanting. It also indicated that LAI significantly influenced (by 15%) deficit irrigation for both crops and methods that achieved the highest yield. The predicted LAI was obtained best-fitting with the observed values, which indicated that the AccuPAR-ceptometer is suitable to be used.

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