scholarly journals Ecofisiologia da cana-de-açúcar no sub-bosque de canafístula em arranjos de sistema agroflorestal

2017 ◽  
Vol 7 (4) ◽  
pp. 464 ◽  
Author(s):  
Elvis Felipe Elli ◽  
Braulio Otomar Caron ◽  
Gizelli Moiano De Paula ◽  
Elder Eloy ◽  
Felipe Schwerz ◽  
...  
Keyword(s):  
Experimental Design ◽  
Analysis Of Variance ◽  
Photosynthetically Active Radiation ◽  
Thermal Characteristics ◽  
Agroforestry System ◽  
Agroforestry Systems ◽  
Leaf Temperature ◽  
Line System ◽  
Active Radiation ◽  
North And South

The objective of this study was to evaluate physiological and thermal aspects of sugarcane, in North and South oriented lines, in ‘canafístula’ understory under two plant arrangements in an agroforestry system. The experimental design was a completely randomized block in a 2x2x6 factorial, with two agroforestry systems (strip and line), two evaluation lines (North and South) and at six times a day (9am, 10am, 12pm, 2pm, 3pm and 4pm) with three repetitions. The evaluated characteristics were: incident photosynthetically active radiation (RFA), leaf temperature (TF), resistance to vapor diffusion (RS) and transpiration (E) using a digital porometer LI-1600 LI-COR. Analysis of variance revealed differences for the interaction of agroforestry system x evaluation line x time, for all variables. The physiological and thermal characteristics of sugarcane are influenced by plant arrangement, agroforestry system and the local evaluation within the system. The strip system lead to a higher available amount of RFA in its understory, which reflects in increased RS values and reduced E of sugarcane. The South line presented higher E for sugarcane in the morning period in strip system and lower during the afternoon for the line system, due to higher TF values.

scholarly journals Performance of Aroid under Jackfruit-Based Agroforestry System in Terrace Ecosystem of Bangladesh

2019 ◽  
Vol 23 (2) ◽  
pp. 79-87
Author(s):  
ZA Riyadh ◽  
MA Rahman ◽  
MG Miah ◽  
SR Saha ◽  
MA Hoque ◽  
...  
Keyword(s):  
Agroforestry System ◽  
Agroforestry Systems ◽  
Yield Reduction ◽  
Cost Ratio ◽  
Land Equivalent Ratio ◽  
Artocarpus Heterophyllus ◽  
Active Radiation ◽  
Benefit Cost Ratio ◽  
Sole Cropping ◽  
Benefit Cost

The terrace ecosystem is considered as hotspot of jackfruit tree (Artocarpus heterophyllus Lam) in Bangladesh having potential for understory cropping. However, most of the jackfruit orchards are often found utilized or underutilized. A field experiment was conducted under the jackfruit orchard to study the performance of aroids (Colocasia esculenta L.) from April to October, 2017 in Belabo upazila of Narsingdi district. Four distances (1, 2, 3 and 4 m) from the base of jackfruit tree were considered for aroid planting to evaluate its performance as agroforestry crop in comparison to sole aroid. Land use and economic performances of agroforestry and sole systems were also evaluated. The results indicated that the production of jackfruit increased by 62.73%, while the yield of aroid reduced by 33.48% in agroforestry systems as compared to the yields of sole (non-agroforestry) systems. In agroforestry system, the photosynthetically active radiation (PAR) was severely reduced by 85-77% on aroid crop that caused yield reduction. It was also observed that soil temperature was lower in agroforestry system as compared to sole cropping of aroid, while soil moisture showed inverse trend in sole jackfruit. Economic analysis in terms of benefit cost ratio (BCR) was 2.60 in agroforestry, while the BCR of sole aroid was only 1.83. The land equivalent ratio (LER) was 2.31 in agroforestry system. The present results indicate that aroid cultivation in jackfruit-based agroforestry system under terrace ecosystem can ensure overall higher production and improve economic return. Ann. Bangladesh Agric. (2019) 23(2) : 79-87

scholarly journals Farmers' perceptions towards agroforestry systems in North and South Kordofanstates, Sudan

2015 ◽  
Vol 4 (2) ◽  
pp. 53-67
Author(s):  
Kamal Eldin Mohammed Fadl ◽  
Salah E Mahmoud ◽  
Zainab M Hamad
Keyword(s):  
Tree Species ◽  
Family Income ◽  
Gum Arabic ◽  
Crop Productivity ◽  
Agroforestry System ◽  
Agroforestry Systems ◽  
Environmental Benefits ◽  
Current Status ◽  
Acacia Senegal ◽  
North And South

This study was conducted during 2010 and 2011 in North and South Kordofan States with objectives of to identify and assess the most important agroforestry systems, to characterize major tree species in different agroforestry system, to prioritize major constraints on agroforestry systems in the region, and to study the current status of gum Arabic trees and their contribution on farmers livelihood. Data were collected through community meeting, individual interviews and direct field observation. The common agroforestry systems in the region are scatter trees on farm land, followed by wind breaks and boundary planting. The important trees in the study area are Acacia senegal83%, followed by Fadherbia albida 46%, Ziziphus spina- christia43% and Balanites aegyptiaca 41%. The most important field crops that cultivated in agroforestry system are groundnuts, millet, sorghum, sesame and roselle. The environmental benefits of trees in farm which was identified by the respondents include protection of farm against wind erosion, improvement of the soil properties, improvement of the micro-climate and providing a source for income which was indicated by the majority of respondents. Across all sites 93% of respondents showed that gum Arabic have a significant contribution to their family income. The study recommended that a multi-purpose tree species such as Acacia senegal should be maintained for amelioration of soils fertility and increase crop productivity in the fragile ecosystems such as that of the study sites. DOI: http://dx.doi.org/10.3126/ije.v4i2.12624 International Journal of Environment Vol.4(2) 2015: 53-67

scholarly journals A Model for Net Photosynthesis of Rose Leaves as a Function of Photosynthetically Active Radiation, Leaf Temperature, and Leaf Age

1990 ◽  
Vol 115 (3) ◽  
pp. 486-491 ◽  
Author(s):  
J.H. Lieth ◽  
C.C. Pasian
Keyword(s):  
Photosynthetically Active Radiation ◽  
Mathematical Description ◽  
Leaf Age ◽  
Net Photosynthesis ◽  
Leaf Temperature ◽  
Rosa Hybrida ◽  
Crop Canopy ◽  
Active Radiation ◽  
The Relationship

A mathematical description for the relationship between the rate of rose (Rosa hybrida L.) leaf net photosynthesis and photosynthetically active radiation, leaf temperature, and leaf age is developed. The model provides a tool for the prediction of these rates for leaves growing in a rose crop canopy.

Net photosynthesis and stomatal conductance of red spruce twigs before and after twig detachment

1993 ◽  
Vol 23 (4) ◽  
pp. 716-721 ◽  
Author(s):  
Fan-Rui Meng ◽  
Paul A. Arp
Keyword(s):  
Stomatal Conductance ◽  
Relative Humidity ◽  
New Brunswick ◽  
Photosynthetically Active Radiation ◽  
Regression Models ◽  
Net Photosynthesis ◽  
Leaf Temperature ◽  
Red Spruce ◽  
Active Radiation ◽  
Before And After

Rates of net photosynthesis and stomatal conductance of red spruce (Picearubens Sarg.) twigs were measured in field conditions before and after twig detachment on clear midsummer days in New Brunswick. Although these variables did not change significantly within about 6 min after twig detachment, they did drop continually after detachment. Regression models for the rates of net photosynthesis and stomatal conductance were developed that can be used to simulate this drop. Photosynthetically active radiation, leaf temperature, relative humidity, and CO2 concentration were the principal covariates in these models. The regressions improved by including simulated leaf moisture values in the analysis of data obtained after twig detachment.

scholarly journals Physiological response of cidró to different water replacement levels in two seasons of the year

2017 ◽  
Vol 35 (2) ◽  
pp. 203-209 ◽  
Author(s):  
Denise Schmidt ◽  
Braulio O Caron ◽  
Luciano Schwerz ◽  
Paulo A Manfron ◽  
Elvis F Elli ◽  
...  
Keyword(s):  
Water Availability ◽  
Photosynthetically Active Radiation ◽  
Physiological Response ◽  
Leaf Temperature ◽  
Diffusion Resistance ◽  
Vapor Flow ◽  
Vapor Diffusion ◽  
Active Radiation ◽  
Adverse Weather ◽  
Water Replacement

ABSTRACT We aimed to determine the response of cidró (Aloysia triphylla) submitted to different water replacement levels in summer and winter, in order to understand and relate the plant physiological performance under adverse weather conditions. The research was developed in a protected environment, in the city of Frederico Westphalen, Rio Grande do Sul State, Brazil. The experimental design was completely randomized, arranged in a 2x4x2 factorial scheme, two seasons of the year (summer and winter), four water availability (50, 75, 100, 125% of ETo) and two faces of leaf (abaxial and adaxial), with four replications. There were evaluated stomatal vapor diffusion resistance (s/cm), transpiration (µg/cm2/s) and leaf temperature (°C), on both faces of the leaf from 10 a.m. to 11 a.m., 1 p.m. to 2 p.m. and 4 p.m. to 5 p.m., 45 days after the beginning of the season. We concluded that the physiological response of cidró plants was influenced by water replacement levels, in a different way according to the seasons of the year. The summer season was responsible for the highest values of incident photosynthetically active radiation, leaf temperature, transpiration and stomatal vapor diffusion resistance. The reduction in water availability promoted the increase in values for stomatal resistance to vapor flow, reducing leaf transpiration rate. The incident photosynthetically active radiation, leaf temperature and transpiration showed highest values on the abaxial face of the studied species.

scholarly journals Production and vegetative growth of coffee trees under fertilization and shade levels

2010 ◽  
Vol 67 (6) ◽  
pp. 639-645 ◽  
Author(s):  
Catalina Jaramillo-Botero ◽  
Ricardo Henrique Silva Santos ◽  
Herminia Emilia Prieto Martinez ◽  
Paulo Roberto Cecon ◽  
Merci Pereira Fardin
Keyword(s):  
Leaf Area ◽  
Photosynthetically Active Radiation ◽  
Agroforestry Systems ◽  
Vegetative Development ◽  
Radiation Reduction ◽  
Active Radiation ◽  
Light Reduction ◽  
The Third ◽  
Water Competition ◽  
Number Of Leaves

It is difficult to separate the effects of light reduction versus nutrient and water competition in agroforestry systems. The objective of this experiment was to evaluate the effect of shading and fertilizer supply on the vegetative development and yield of Coffea arabica over six years. The coffee trees were covered with shade screens (photosynthetically active radiation reduction up to 48%) and fertilized from 100 to 40% of the recommended amount from 2001 on. Leaf area, number of leaves, number of nodes, leaf area per branch and, yield were determined. Although no effect of fertilization was found, shading influenced the number of nodes, leaf area and production from the third year on. The number of nodes and yield decreased as shading increased. The effect of the yield bienniallity was more evident in the unshaded trees, which yielded an average of 2,646 kg ha¹. The trees under 48% shading yielded an average of 2,094 kg ha¹. After 2004 the leaf area per branch increased as the shade increased, at the end of both the maximum and minimum growth periods. During the first three years, the coffee trees do not change their vegetative or productive characteristics as a response to shading. The shade effects become more intense after the beginning of the higher yield period. The shaded coffee trees have a larger leaf area and a smaller number of nodes than the coffee trees under full sun. The yield decreases as photosynthetically active radiation limitation increases, and yield bienniallity is less intense in shaded trees.

scholarly journals Reflective material on cultivation benches and rice straw over the substrate in papaya seedling production

2020 ◽  
Vol 11 (8) ◽  
pp. 1713-1723
Author(s):  
Rogério Do Carmo Cabral ◽  
Daniele Ferreira Cavalcante ◽  
Eduardo Pradi Vendruscolo ◽  
Murilo Battistuzzi Martins ◽  
Tiago Zoz ◽  
...  
Keyword(s):  
Experimental Design ◽  
Rice Straw ◽  
Environmental Conditions ◽  
Photosynthetically Active Radiation ◽  
Aluminum Foil ◽  
Joint Analysis ◽  
Seedling Production ◽  
High Quality ◽  
Active Radiation ◽  
Randomized Experimental Design

Improving environmental conditions in the production of seedlings by expanding the distribution of photosynthetically active radiation in abaxial leaves and protecting the substrate with straw can promote the production of higher quality seedlings. This study aimed to evaluate the reflective materials over the cultivation bench and the use of rice straw over the substrate in the formation of papaya seedlings of the group ‘Formosa’. The joint analysis was performed considering a completely randomized experimental design in a 3 x 2 factorial scheme, with five replications and six seedlings per plot. The use of aluminized screen (Aluminet®) and aluminum foil with an area of 1 m x 1.2 m as reflective material on the cultivation bench and treatment without reflective material were evaluated. Also, the presence and absence of a rice straw layer with 5 cm height, as covering over the substrate were evaluated. In the benches with aluminum foil and without reflective material, the seedling production without rice straw over the substrate provided papaya seedlings of higher quality than the rice straw over the substrate. The aluminum foil produced high-quality papaya seedlings in the treatments with rice straw over the substrate. The aluminized screen on the cultivation bench was not favorable for the papaya seedlings production.

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