scholarly journals Efisiensi Penggunaan Cahaya Matahari oleh Tebu pada Berbagai Tingkat Pemupukan Nitrogen dan Fosfor

1970 ◽  
Vol 40 (3) ◽  
Author(s):  
Wawan Pembengo ◽  
, Handoko ◽  
, Suwarto
Keyword(s):  
Dry Matter ◽  
Phosphorus Deficiency ◽  
Block Design ◽  
Canopy Structure ◽  
Leaf Nitrogen ◽  
Light Use Efficiency ◽  
Nitrogen And Phosphorus ◽  
Area Index ◽  
P Fertilizer ◽  
Use Efficiency

Light use efficiency is a crucial parameter in plant growth associated with accumulation of energy interception. Nitrogen and phosphorus deficiency reduce leaf area index (LAI) and specific leaf nitrogen and phosphorus (SLN and SLP) content and reduce efficiency of light intercepted by plant canopy structure. This research was conducted in Kebun Bunga Mayang PTPN VII, North Lampung Regency, Lampung Province (04050’S, 104052’E, 38 m above sea level) from July 2008 to September 2009. Treatments were distributed in the field under a randomized complete block design factorial with three replications. The increase in nitrogen fertilizer (N) improved sugarcane light use efficiency. The light use efficiency of the sugarcane plants fertilized with 225 kg N ha-1 was 2.29 g MJ-1 at maximum stem phase. On the contrary, the increasing of phosphor (P) fertilizer did not affect light use efficiency but increased stem dry matter at maximum seedling phase or about 3 month after planting (3 MAP), at maximum stem phase (9 MAP), and at harvest (11 MAP); total dry matter at seedling phase (5 MAP) and at maximum stem phase (9 MAP). Nitrogen did not interact with P in affecting light use efficiency. Keywords: fertilization N and P, interception radiation, light use efficiency, sugarcane

Photosynthetic attributes and seed yield of sunflower (Helianthus annuus L.) as influenced by different levels and ratios of nitrogen and phosphorus fertilizers

2003 ◽  
Vol 51 (2) ◽  
pp. 149-155 ◽  
Author(s):  
N. Thavaprakash ◽  
G. Senthilkumar ◽  
S. D. Sivakumar ◽  
M. Raju
Keyword(s):  
Leaf Area ◽  
Seed Yield ◽  
Dry Matter ◽  
Block Design ◽  
Research Station ◽  
Dry Matter Accumulation ◽  
Nitrogen And Phosphorus ◽  
Area Index ◽  
Green Leaves ◽  
Photosynthetic Attributes

A field experiment was conducted at the Main Research Station, University of Agricultural Sciences, Dharwad, India, on medium black soils during the kharif (wet) season of 1999. The experiment was laid out in a randomized complete block design with varying N/P ratios (0.67 to 2.00) along with a control with a constant level of potassium (60 kg ha-1). The results revealed that the number of green leaves plant-1, the dry matter accumulation in the leaves, leaf area (dm2 plant-1) and leaf area index (LAI) increased up to the flowering stage (65 DAS) and thereafter declined. In the early stages (seedling and button stages) there was no significant variation with respect to the number of green leaves plant-1 among the treatments except in the control. Similarly, leaf area and LAI did not vary at the seedling stage. Treatments receiving N/P ratios of ?1.0 or 1.0 with higher doses of nitrogen (120 kg N ha-1) gave a significantly higher number of green leaves plant-1, leaf area and LAI as compared to N/P ratios of <1.0 and the control in later stages. The dry matter accumulation in the leaves (g plant-1) differed in all the stages, but higher values were recorded in these same treatments. Thus, due to the higher number of green leaves, higher LAI and greater dry matter accumulation in the leaves, the treatments with an N/P ratio of ?1.0 or 1.0 with 120 kg N ha-1 produced higher seed yields (3188 to 3554 kg ha-1) than other N/P ratios (2761 to 3009 kg ha-1). The highest yield (3554 kg ha-1) was recorded with an N/P ratio of 1.0 in the treatment receiving 120 kg N and 120 kg P2O5 ha-1. The correlation coefficients between these photosynthetic attributes and seed yield were also positive and significant.

Nitrogen-limited light use efficiency in wheat crop simulators: comparing three model approaches

2015 ◽  
Vol 154 (6) ◽  
pp. 1090-1101 ◽  
Author(s):  
A. M. RATJEN ◽  
H. KAGE
Keyword(s):  
Dry Matter ◽  
Dry Matter Production ◽  
Wheat Crop ◽  
Light Use Efficiency ◽  
Data Set ◽  
Area Index ◽  
N Concentration ◽  
Matter Production ◽  
Use Efficiency ◽  
Critical N Concentration

SUMMARYThree different explanatory indicators for reduced light use efficiency (LUE) under limited nitrogen (N) supply were evaluated. The indicators can be used to adapt dry matter production of crop simulators to N-limited growth conditions. The first indicator, nitrogen factor (NFAC), originates from the CERES-Wheat model and calculates the critical N concentration of the shoot as a function of phenological development. The second indicator, N nutrition index (NNI), calculates a critical N concentration as a function of shoot dry matter. The third indicator, specific leaf nitrogen (SLN) index (SLNI), has been newly developed. It compares the actual SLN with the maximum SLN (SLNmax). The latter is calculated as a function of the green area index (GAI). The comparison was based on growth curves and fitted to empirical data, and was carried out independently from a dynamic crop model. The data set included four growing seasons (2004–2006, 2012) in Northern Germany and seven modern bread wheat cultivars with varying N fertilization levels (0–320 kg N/ha). The influence of N shortage on LUE was evaluated from the beginning of stem elongation until flowering. With the exception of 2005, the highest productivity was observed for the highest N level. A moderate N shortage primarily reduced GAI and therefore light interception, while LUE remained stable under moderate N shortage. The relative LUE (rLUE) of a specific day was defined as the ratio of actual to maximal LUE. None of the indicators was proportional to rLUE, but the relationships were described well by quadratic plateau curves. The correlation between simulated and measured rLUE was significant for all explanatory indicators, but different in terms of mean absolute error and coefficient of determination (R2). The performance of SLNI and NNI was similar, but the goodness of prediction was much lower for NFAC. Compared with NNI and NFAC, SLNI corresponded to leaf N and was therefore sensitive to N translocation from leaves to growing grains during the reproductive stage. For this reason, SLNI may have the potential to improve simulation of dry matter production in wheat crop simulators.

scholarly journals Effect of nitrogen and phosphorus on growth and seed yield of French bean

2016 ◽  
Vol 41 (4) ◽  
pp. 759-772
Author(s):  
SS Kakon ◽  
MSU Bhuiya ◽  
SMA Hossain ◽  
Q Naher ◽  
Md DH Bhuiyan
Keyword(s):  
Seed Yield ◽  
Dry Matter ◽  
Field Experiments ◽  
Agricultural Research ◽  
Block Design ◽  
French Bean ◽  
Dry Matter Production ◽  
Nitrogen And Phosphorus ◽  
Area Index ◽  
Matter Production

Field experiments were conducted during rabi (winter) seasons of 2010-11 and 2011-12 at the Bangladesh Agricultural Research Institute (BARI), Joydebpur, Gazipur to study the effects of nitrogen and phosphorus on growth, dry matter production and yield of French bean. A randomized complete block design was followed with 10 combinations of N (0,50, 100, 150 and 200) and P (0,22, 33, 44 and 55) kg ha-1 along with a blanket dose of control. All the treatments showed the maximum leaf area index (LAI) at 65 days after sowing (DAS). All the treatments showed the maximum total dry matter production, crop growth rate and net assimilation rate at harvest and at 55-65 DAS, respectively in both the years. LAI, dry matter production, CGR, NAR and seed yield significantly increased with the increase in nitrogen and phosphorus level upto 150 kg N and 44 P kg ha-1 , respectively. Similar trend was followed in maximum number of pods (9.45) and seed yield (1563.33 kg ha-1). The treatment comprises with 150 kg N and 44 P Kg ha-1 gave the highest seed yield which was 51.40 and 54.30 % higher than control plots.Bangladesh J. Agril. Res. 41(4): 759-772, December 2016

scholarly journals Relationship between Light Use Efficiency and Photochemical Reflectance Index Corrected Using a BRDF Model at a Subtropical Mixed Forest

2020 ◽  
Vol 12 (3) ◽  
pp. 550
Author(s):  
Li Ma ◽  
Shaoqiang Wang ◽  
Jinghua Chen ◽  
Bin Chen ◽  
Leiming Zhang ◽  
...  
Keyword(s):  
Laser Scanning ◽  
Mixed Forest ◽  
Canopy Structure ◽  
Terrestrial Laser Scanning ◽  
Light Use Efficiency ◽  
Vegetation Canopy ◽  
Area Index ◽  
Photochemical Reflectance Index ◽  
Use Efficiency ◽  
Point Data

Light use efficiency (LUE) is a key indicator of vegetation photosynthesis, which provides important insights into how vegetation productivity responds to environmental conditions. The photochemical reflectance index (PRI) is based on reflectance at 531 and 570 nm, which reflects the xanthophyll cycle process of plants under different radiation conditions, and makes LUE related to plant optical characteristics. In this study, tower-based PRI and eddy covariance (EC) based LUEs were used to explore the ability of PRI to track LUE variations in a subtropical, evergreen mixed forest in South China. The results indicate that there is a stronger relationship between PRI and LUE, corrected by the bidirectional reflectance distribution function (BRDF), where R2 = 0.46 before correction and R2 = 0.60 after correction. Generally, PRI is able to capture diurnal and seasonal changes in LUE. Simultaneously, this study highlights a significant correlation between LUE and PRI, but there is also a large seasonal difference in its correlation. The correlation in winter was significantly stronger than summer. The strongest correlation is found in November (R2 = 0.91) and the weakest is in July (R2 = 0.34). Photosynthetically active radiation (PAR) had a strong influence on the LUE-PRI relationship, while vapor pressure deficit (VPD) and air temperature (Ta) had negative influences on the relationship between LUE and PRI. Terrestrial laser scanning is used to retrieve the vertical structure of forest crown. Our results show that the vegetation canopy structure (i.e., effective leaf area index, LAIe), extracted from terrestrial laser scanning (TLS) point data in subtropical mixed forests, had a weak influence on LUE. Our research suggests that environmental factors and vegetation canopy structures should be considered when using PRI to accurately estimate LUE.

scholarly journals Contrasting Development of Canopy Structure and Primary Production in Planted and Naturally Regenerated Red Pine Forests

Forests ◽  
2019 ◽  
Vol 10 (7) ◽  
pp. 566 ◽  
Author(s):  
Laura J. Hickey ◽  
Jeff Atkins ◽  
Robert T. Fahey ◽  
Mark T. Kreider ◽  
Shea B. Wales ◽  
...  
Keyword(s):  
Primary Production ◽  
Canopy Structure ◽  
Structural Complexity ◽  
Red Pine ◽  
Stem Density ◽  
Light Use Efficiency ◽  
Planted Forests ◽  
Area Index ◽  
Use Efficiency ◽  
Naturally Regenerated Stands

Globally, planted forests are rapidly replacing naturally regenerated stands but the implications for canopy structure, carbon (C) storage, and the linkages between the two are unclear. We investigated the successional dynamics, interlinkages and mechanistic relationships between wood net primary production (NPPw) and canopy structure in planted and naturally regenerated red pine (Pinus resinosa Sol. ex Aiton) stands spanning ≥ 45 years of development. We focused our canopy structural analysis on leaf area index (LAI) and a spatially integrative, terrestrial LiDAR-based complexity measure, canopy rugosity, which is positively correlated with NPPw in several naturally regenerated forests, but which has not been investigated in planted stands. We estimated stand NPPw using a dendrochronological approach and examined whether canopy rugosity relates to light absorption and light–use efficiency. We found that canopy rugosity increased similarly with age in planted and naturally regenerated stands, despite differences in other structural features including LAI and stem density. However, the relationship between canopy rugosity and NPPw was negative in planted and not significant in naturally regenerated stands, indicating structural complexity is not a globally positive driver of NPPw. Underlying the negative NPPw-canopy rugosity relationship in planted stands was a corresponding decline in light-use efficiency, which peaked in the youngest, densely stocked stand with high LAI and low structural complexity. Even with significant differences in the developmental trajectories of canopy structure, NPPw, and light use, planted and naturally regenerated stands stored similar amounts of C in wood over a 45-year period. We conclude that widespread increases in planted forests are likely to affect age-related patterns in canopy structure and NPPw, but planted and naturally regenerated forests may function as comparable long-term C sinks via different structural and mechanistic pathways.

scholarly journals MORPHOLOGICAL AND PRODUCTIVE CHARACTERIZATION OF FORAGE CACTUS VARIETIES

2015 ◽  
Vol 28 (3) ◽  
pp. 230-238 ◽  
Author(s):  
PHILIPE LIMA DE AMORIM ◽  
JANAINA AZEVEDO MARTUSCELLO ◽  
JOSÉ TEODORICO DE ARAÚJO FILHO ◽  
DANIEL DE NORONHA FIGUEIREDO VIEIRA DA CUNHA ◽  
LIANA JANK
Keyword(s):  
Block Design ◽  
Morphological Characteristics ◽  
Correlation Coefficients ◽  
Dry Mass ◽  
Negative Effects ◽  
Breeding Programs ◽  
Area Index ◽  
Promising Alternative ◽  
Randomized Block Design ◽  
Use Efficiency

ABSTRACT: Cultivars of the genus Nopalea are known in Brazil for being tolerant to cochineal carmine attacks, thus making the cultivation of this genus a promising alternative for mitigating the negative effects of this insect on the production of biomass. With the objectives of characterizing morphologically spineless forage cactus varieties and identify morphological characteristics that may be the focus in spineless forage cactus breeding programs, an experiment was conducted in a completely randomized block design with 11 treatments and four replications. The variety Alagoas showed the highest values of weight, area and volume of cladodes. The varieties Negro Michoacan F7 and V7, Tamazunchale V12 showed the highest values of the cladode area index, the total volume of cladodes and total fresh mass production. The varieties Negro Michoacan V7 and F7 presented the highest water use efficiency and dry mass yield. Cladode volume showed the highest correlation coefficients with the fresh weight of cladodes. Aiming the release of varieties for biomass production, varieties Negro Michoacan F7, V7 and Tamazunchale V12 may substitute the Miúda variety. The number and cladode area index may be used as criteria for selection of superior varieties in breeding programs.

scholarly journals Growth and yield of wheat at different dates of sowing under chrland ecosystem of Bangladesh

2017 ◽  
Vol 14 (2) ◽  
pp. 147-154 ◽  
Author(s):  
MM Kamrozzaman ◽  
MAH Khan ◽  
S Ahmed ◽  
N Sultana
Keyword(s):  
Growth Rate ◽  
Leaf Area Index ◽  
Leaf Area ◽  
Dry Matter ◽  
Block Design ◽  
Grain Filling ◽  
Crop Growth ◽  
Growth And Yield ◽  
Area Index ◽  
Crop Growth Rate

An experiment was conducted at Sadipur charland under Farming System Research and Development Site, Hatgobindapur, Faridpur, during rabi season of 2012-13 and 2013-14 to study the growth and yield performance of cv. BARI Gom-24 as affected by different dates of sowing under Agro-ecological Zone-12 (AEZ-12) of Bangladesh. The experiment was laid out in randomized complete block design with six replications, comprising five different dates of sowing viz. November 5, November 15, November 25, December 5 and December 15. Results reveal that the tallest plant, leaf area index, total dry matter, and crop growth rate were observed in November 25 sown crop and leaf area index, total dry matter and crop growth rate were higher at booting, grain filling, and tillering stages of the crop. Maximum effective tillers hill-1 (3.49), spikes m-2, (311), number of grains spike-1 (42.20) and 1000-grain weight (52.10 g) were produced by November 25 sown crop exhibited the highest grain (4.30 t ha-1) and straw yield (4.94 t ha-1) as well as harvest index (46.88%) of the crop. Lowest performance was observed both in early (November 5) and late sown crop (December 15). The overall results indicated that November 25 sown crop showed better performance in respect of growth and yield of wheat under charland ecosystem of Bangladesh.J. Bangladesh Agril. Univ. 14(2): 147-154, December 2016

scholarly journals Effect of Zinc and Boron on Growth and Yield of Okra (Abelmoschus esculentus L.)

2020 ◽  
pp. 41-47
Author(s):  
Nusrat Jahan ◽  
Md. Ashabul Hoque ◽  
Md. Rasal-Monir ◽  
Sumya Fatima ◽  
Mohammad Nurul Islam ◽  
...  
Keyword(s):  
Dry Matter ◽  
Block Design ◽  
Fruit Weight ◽  
Fruit Yield ◽  
Growth And Yield ◽  
Area Index ◽  
Spad Value ◽  
Randomized Complete Block Design ◽  
Number Of Leaves ◽  
Fruit Diameter

The study was carried out to find out the effect of zinc (Zn) and boron (B) on growth and yield of okra (BARI Dherosh 1). The experiment was laid out in Randomized Complete Block Design (RCBD) with three replications. The treatments of the experiment were, T0 (without Zn or B), T1 (20 kg Zn ha-1), T2 (30 kg Zn ha-1), T3 (10 kg B ha-1), T4 (20 kg B ha-1), T5 (20 kg Zn ha-1 + 10 kg B ha-1), T6 (20 kg Zn ha-1 + 20 kg B ha-1), T7 (30 kg Zn ha-1 + 10 kg B ha-1) and T8 (30 kg Zn ha-1 + 20 kg B ha-1) were undertaken to evaluate the best results of the study. The highest plant height was found in T8 (30 kg Zn ha-1 + 20 kg B ha-1) but the highest number of leaves plant-1 was recorded from T7 (30 kg Zn ha-1 + 10 kg B ha-1). On the other hand, the maximum leaf area index, SPAD value, mean fruit weight, fruit length, fruit diameter, fruit dry matter (%), number of fruits plant-1, fresh fruit weight plant-1 , fruit yield plot-1 and fruit yield ha-1 were found in T7 (30 kg Zn ha-1 + 10 kg B ha-1), while the control (T0) showed lowest performance for the respected parameters. It is strongly concluded that 30 kg Zn ha-1 with 10 kg B ha-1 combination may be helpful for okra cultivation in the field level to increase okra production.

scholarly journals Yield and vegetative growth of cactus pear at different spacings and under chemical fertilizations

2016 ◽  
Vol 20 (6) ◽  
pp. 564-569 ◽  
Author(s):  
João A. da Silva ◽  
Sérgio L. R. Donato ◽  
Paulo E. R. Donato ◽  
Evilasio dos S. Souza ◽  
Milton C. Padilha Júnior ◽  
...  
Keyword(s):  
Plant Growth ◽  
Plant Height ◽  
Vegetative Growth ◽  
Dry Matter ◽  
Block Design ◽  
Plant Age ◽  
Cactus Pear ◽  
Area Index ◽  
Randomized Block Design

ABSTRACT The objective was to evaluate the effect of different spacings and mineral fertilizations on cactus pear growth and production in a randomized block design, with three replicates, in a 3 x 4 factorial scheme: three spacings, 1.00 x 0.50 m, 2.00 x 0.25 m and 3.00 x 1.00 x 0.25 m, and four fertilizations, 000-000-000, 000-150-000, 200-150-000 and 200-150-100 kg ha-1 of N, P2O5 and K2O, respectively. Plant growth was evaluated between 90 and 390 days and production and growth were evaluated at 620 days after planting. There were significant interactions between spacing and fertilization for plant height, number of cladodes and cladode area index from 90 to 390 days and for production of fresh and dry matter at 620 days after planting. Spacing influenced cladode area index, while fertilization influenced plant height, number of cladodes and cladode area index at 620 days after planting. Plant height showed cubic effect for the days after planting. Number of cladodes and cladode area index were dependent on spacing, fertilization and plant age, and fitted to cubic models. The best results of growth and production of fresh and dry matter are associated with NPK and NP fertilizations and the spacing of 1.00 x 0.50 m.

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