scholarly journals Effects of UV-B Radiation on Oxalate Content of Silver Beet Leaves

2012 ◽  
Vol 1 (4) ◽  
pp. 1 ◽  
Author(s):  
H. A. Presswood ◽  
R. Hofmann ◽  
G. P. Savage
Keyword(s):  
New Zealand ◽  
Photosynthetically Active Radiation ◽  
Dry Matter ◽  
Active Radiation ◽  
Silver Beet

Silver beet (<em>Beta vulgaricus </em>var. <em>cicla</em>) a common vegetable in New Zealand is known to contain high levels of oxalates in the leaves. Silver beet plants were grown in afield trial under glass and perspex sheets which filtered sunlight reaching the plants. After eight weeks of growth, the plants were harvested and the total, soluble and insoluble oxalate content of the leaves of the plants grown under the two filter treatments and a no-frame control were measured. Perspex allowed the transmission of UV-A, UV-B and photosynthetically active radiation (PAR), whereas glass excluded UV-B radiation. No significant differences between the perspex treatment and the no-frame control were observed when the data was compared on a wet matter (WM) or dry matter (DM) basis Shielding the growing plants with glass significantly reduced the total oxalate and soluble oxalates to 83 and 84% respectively when compared to the perspexand no-frame treatments.

A Pear and Vegetable Interculture System: Land Equivalent Ratio, Light Use Efficiency and Productivity

1986 ◽  
Vol 22 (4) ◽  
pp. 383-392 ◽  
Author(s):  
S. M. Newman
Keyword(s):  
Photosynthetically Active Radiation ◽  
Dry Matter ◽  
Spatial Arrangement ◽  
Yield Reduction ◽  
Light Use Efficiency ◽  
Land Equivalent Ratio ◽  
Active Radiation ◽  
Use Efficiency ◽  
Pear Trees ◽  
Efficiency And Productivity

SUMMARYThe productivity, land equivalent ratios (LERs) and light use efficiency of a pear and radish interculture system were assessed. Pear yield was unaffected by intercropping. Relative yields for the radish component varied between 0.5–1.01 depending upon the yield index and spatial arrangement employed. This gave LER values for the system of 1.5–2.01. The overall trans-missivity of the pear canopy was 73%. A 47% reduction in photosynthetically active radiation (PAR) gave a yield reduction of 65% in terms of number of saleable radish, but did not affect total dry matter productivity. Reductions in radish yield directly beneath pear trees was thought to be due to other factors besides PAR. The total dry matter productivity of a system containing five successive radish crops was estimated at 26.25 tonnes ha−1 yr−1.

scholarly journals Emerald zoyzia grass development regarding photosynthetically active radiation in different slopes

2012 ◽  
Vol 32 (3) ◽  
pp. 501-509 ◽  
Author(s):  
Ruchele M. Coan ◽  
José E. P. Turco ◽  
Kathia F. L. Pivetta ◽  
Madson N. da Costa ◽  
Caroline de M. D'A. Mateus
Keyword(s):  
Photosynthetically Active Radiation ◽  
Dry Matter ◽  
Global Radiation ◽  
Global Solar Radiation ◽  
State University ◽  
Active Radiation ◽  
Agricultural Engineering ◽  
Paulo State ◽  
Tukey Test ◽  
Engineering Department

With this study, the objective was to estimate the photosynthetically active radiation (PAR) and to correlate it with the dry matter (MMSPA) of the emerald zoysia (Zoysia japonica Steud.) on surfaces with different expositions and slopes. The research was conducted at the Experimental Watershed of the Agricultural Engineering Department, School of Agriculture and Veterinary Sciences of São Paulo State University (FCAV/UNESP), Brazil, where the surfaces (H, 10 N, 30 N, 50 N, 10 S, 30 S, 50 S, 10 L, 30 L, 50 L, 10 O, 30 O and 50 O) were used. To obtain the global solar radiation, it was installed an automated weather station where the PAR (dependent variable) was obtained by the equation y = a + bx, and the global radiation was independent. To compare means of MMSPA, it was used the Tukey test at 5% probability, and to assess the relation PAR/MMSPA, the simple linear correlation coefficient. The result showed that the accumulation of these effects in the PAR increases with North exposure and decreases with the South, and exposure to 50N is most suitable for slopes, not having correlation between the PAR and the MMSPA for the surfaces evaluated for the study period.

Simulation of leaf area and dry matter production of tobacco leaves based on product of thermal effectiveness and photosynthetically active radiation

2013 ◽  
Vol 33 (22) ◽  
pp. 7108-7115
Author(s):  
张明达 ZHANG Mingda ◽  
李蒙 LI Meng ◽  
胡雪琼 HU Xueqiong ◽  
李晓燕 LI Xiaoyan ◽  
朱勇 ZHU Yong
Keyword(s):  
Leaf Area ◽  
Photosynthetically Active Radiation ◽  
Dry Matter ◽  
Dry Matter Production ◽  
Tobacco Leaves ◽  
Active Radiation ◽  
Matter Production

scholarly journals Stalk dry mass and industrial yield of 16 varieties of sugar cane cultivated under water restriction

2020 ◽  
pp. 1048-1054
Author(s):  
João Carlos Rocha dos Anjos ◽  
Derblai Casaroli ◽  
José Alves Júnior ◽  
Adão Wagner Pego Evangelista ◽  
Rafael Battisti ◽  
...  
Keyword(s):  
Water Use ◽  
Photosynthetically Active Radiation ◽  
Water Demand ◽  
Dry Matter ◽  
Dry Mass ◽  
Water Restriction ◽  
Alcohol Production ◽  
Active Radiation ◽  
Sugarcane Varieties ◽  
Industrial Yield

The great extension of the cultivated area, associated with the low water availability to supply the sugarcane demand in the periods of drought and the high evapotranspiration demand, requires varieties adapted to these specific conditions. The aim of this study was to assess 16 sugarcane varieties regarding the efficiency in water use (EWU) and in photosynthetically active radiation (PAR), cultivated under a water restriction, in the production of stalks dry matter, sugar and alcohol. The experiment was carried out in the Brazilian savannah biome, Goiás State, during the 2011/2012 crop year, in a randomized blocks design, with four repetitions. The treatments consisted of 16 varieties of sugarcane cultivated on a supply of only 50% of the water demand demanded by the crop. The EWU and EUPAR of the varieties were evaluated for the production of stalk dry mass (SDM), sugar and alcohol. During the crop cycle there was sufficient precipitation to supply the water demand of sugarcane; however, the irregular distribution of rainfall resulted in a water deficit of -697 mm during its cycle. The varieties IAC 91-1099, CTC-15, CTC-11, SP 86-0042 and IAC 87-3396 showed higher EWU and better photosynthetically active radiation for the production of stalks dry matter, sugar and alcohol. IACSP 94-2094 and CTC 09 varieties presented the same efficiency in industrial yield and lower dry matter yield than the five following varieties IAC 91-1099, CTC-15, CTC-11, SP 86-0042 and IAC 87-3396. Therefore, these last varieties are the most efficient in water use and photosynthetically active radiation aiming the stalks dry matter, sugar and alcohol production under water restriction.

Estimating dry-matter accumulation in soybean

1977 ◽  
Vol 55 (16) ◽  
pp. 2196-2201 ◽  
Author(s):  
J. L. Heilman ◽  
E. T. Kanemasu ◽  
G. M. Paulsen
Keyword(s):  
Solar Radiation ◽  
Photosynthetically Active Radiation ◽  
Dry Matter ◽  
Dark Respiration ◽  
Field Measurements ◽  
Dry Matter Accumulation ◽  
Soil Water Depletion ◽  
Area Index ◽  
Active Radiation ◽  
Gross Photosynthesis

Equations to estimate gross photosynthesis, respiration, and dry-matter accumulation for soybean from daily estimates of intercepted, photosynthetically active radiation (PAR) were developed from field measurements. We found that gross photosynthesis was a function of intercepted PAR and that 24-h dark respiration was a function of gross photosynthesis. In addition, we developed equations relating intercepted PAR to leaf area index (LAI) and solar radiation. We assumed that gross photosynthesis was reduced when soil-water depletion was greater than 65%. The growth model predicted accumulated dry matter for soybean in 1974, 1975, and 1976 to within 2.7 mg cm−2 of observed values.

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