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Modeling Grain Yield And Straw Yield Of Wheat Using Back Propagation And Genetic Algorithm, Omar Maghawri Ibrahim Hassan Dr. Dec 2014

Modeling Grain Yield And Straw Yield Of Wheat Using Back Propagation And Genetic Algorithm, Omar Maghawri Ibrahim Hassan Dr.

Dr. Omar Maghawri Ibrahim

The first objective of this study was to model the effect of yield components, number of grain/spike, number of spikes/m2, and 1000 kernels weight on the grain yield and straw yield of wheat. An artificial neural network (ANN), multilayer perceptron feed forward neural network (MLP) was used for developing the predictive model. Two different training algorithms: back propagation (BP) and genetic algorithm (GA) were used to train the MLP which structured of three neurons in the input layer, one hidden layer of six neurons, and two neurons in the output layer. The second objective of the current study was to …


Influence Of Nitrogen Fertilizer And Foliar Application Of Salicylic Acid On Wheat, Omar Maghawri Ibrahim Hassan Dr. Nov 2014

Influence Of Nitrogen Fertilizer And Foliar Application Of Salicylic Acid On Wheat, Omar Maghawri Ibrahim Hassan Dr.

Dr. Omar Maghawri Ibrahim

Two cemented plots experiments were carried out during the winter seasons of 2012/2013 and 2013/2014, Soil Salinity Laboratory, Alexandria, Egypt, to study the effect of three levels of salicylic acid (SA) (0, 50, 100 ppm) and three rates of nitrogen fertilizer (75, 100, 125 kg N/feddan) on yield and yield components of wheat (Sakha 93). The experimental design was split plot with four replicates. The results indicated that increasing nitrogen fertilizer rates resulted in significant increase in plant height (cm), number of grain/spike, number of spikes/m2, 1000 grain weight (gm), grain yield (gm/plot), straw yield (gm/plot), and biological yield (gm/plot). …


Performance Assessment Of Some Flax (Linum Usitatissimum L.) Varieties Using Cluster Analysis Under Sandy Soil Conditions, Omar Maghawri Ibrahim Hassan Dr. Jul 2014

Performance Assessment Of Some Flax (Linum Usitatissimum L.) Varieties Using Cluster Analysis Under Sandy Soil Conditions, Omar Maghawri Ibrahim Hassan Dr.

Dr. Omar Maghawri Ibrahim

To assess the performance and the variability of 49 flax varieties based on agronomic parameters using cluster analysis, a field experiment was conducted in 2011/2012 and 2012/2013 winter seasons at the farm of the National Research Center at Nubria district, Albehira Governorate, Egypt. The results revealed high significant difference among all flax varieties in all the studied characters. Letwania-9 and Evelen cultivars surpassed all other varieties in seed and oil yields/ fed. On the other hand, D variety gave the lowest value of seed yield/fed and F variety gave the lowest values of oil% and oil yield/fed. While, G Variety …


Lichens Of Six Vernal Pools In Acadia National Park, Maine, Usa, Jason Barton, Brett Ciccotelli, Jillian E. Gall, Fred C. Olday, Bruce Connery, Tanner B. Harris, Alan M. Fryday, Nishanta Rajakaruna Mar 2014

Lichens Of Six Vernal Pools In Acadia National Park, Maine, Usa, Jason Barton, Brett Ciccotelli, Jillian E. Gall, Fred C. Olday, Bruce Connery, Tanner B. Harris, Alan M. Fryday, Nishanta Rajakaruna

Nishanta Rajakaruna

Whereas lichen-habitat relations have been well-documented globally, literature on lichens of vernal pools is scant. We surveyed six vernal pools at Acadia National Park on Mount Desert Island, Maine, USA for their lichen diversity. Sixty-seven species were identified, including seven species that are new reports for Acadia National Park: Fuscidea arboricola, Hypogymnia incurvoides, Lepraria finkii, Phaeographis inusta, Ropalospora viridis, Usnea flammea, and Violella fucata. Five species are considered uncommon or only locally common in New England: Everniastrum catawbiense, Hypogymnia krogiae, Pseudevernia cladonia, Usnea flammea, and Usnea merrillii. This …


Resolution Of Deep Nodes Yields An Improved Backbone Phylogeny And A New Basal Lineage To Study Early Evolution Of Asteraceae, Jose L. Panero, Susana E. Freire, Luis Ariza Espinar, Bonnie S. Crozier, Gloria E. Barboza, Juan J. Cantero Jan 2014

Resolution Of Deep Nodes Yields An Improved Backbone Phylogeny And A New Basal Lineage To Study Early Evolution Of Asteraceae, Jose L. Panero, Susana E. Freire, Luis Ariza Espinar, Bonnie S. Crozier, Gloria E. Barboza, Juan J. Cantero

Jose L. Panero

A backbone phylogeny that fully resolves all subfamily and deeper nodes of Asteraceae was constructed using 14 chloroplast DNA loci. The recently named genus Famatinanthus was found to be sister to the Mutisioideae–Asteroideae clade that represents more than 99% of Asteraceae and was found to have the two chloroplast inversions present in all Asteraceae except the nine genera of Barnadesioideae. A monotypic subfamily Famatinanthoideae and tribe Famatinantheae are named herein as new. Relation- ships among the basal lineages of the family were resolved with strong support in the Bayesian analysis as (Barnadesioideae (Famatinanthoideae (Mutisioideae (Stifftioideae (Wunderlichioideae– Asteroideae))))). Ancestral state reconstruction …


Spatial And Temporal Dynamics Of Root Exudation: How Important Is Heterogeneity In Allelopathic Interactions?, Jeffrey D. Weidenhamer, Brian K. Mohney, Nader Shihada, Maduka Rupasinghe Jan 2014

Spatial And Temporal Dynamics Of Root Exudation: How Important Is Heterogeneity In Allelopathic Interactions?, Jeffrey D. Weidenhamer, Brian K. Mohney, Nader Shihada, Maduka Rupasinghe

Jeffrey D. Weidenhamer

Understanding allelopathy has been hindered by the lack of methods available to monitor the dynamics of allelochemicals in the soil. Previous work has demonstrated the feasibility of using polydimethylsiloxane (PDMS) microtubing (silicone tubing microextraction, or STME) to construct sampling devices to monitor the release of lipophilic allelochemicals from plant roots. The objective of this study was to use such sampling devices to intensively monitor thiophene fluxes beneath marigolds over several weeks to gain insight into the magnitude of temporal and spatial heterogeneity in these fluxes. Marigolds were grown in rhizoboxes (20.5 x 20.5 x 3.0 cm) with 16 individual STME …


Synthesis And Future Directions: What Have Harsh Environments Taught Us About Ecology, Evolution, Conservation, And Restoration?, Nishanta Rajakaruna, Robert S. Boyd, Tanner B. Harris Jan 2014

Synthesis And Future Directions: What Have Harsh Environments Taught Us About Ecology, Evolution, Conservation, And Restoration?, Nishanta Rajakaruna, Robert S. Boyd, Tanner B. Harris

Nishanta Rajakaruna

No abstract provided.


Additional Lichen Records And Minerological Data From Metal-Contaminated Sites In Maine, Ian D. Medeiros, Alan M. Fryday, Nishanta Rajakaruna Jan 2014

Additional Lichen Records And Minerological Data From Metal-Contaminated Sites In Maine, Ian D. Medeiros, Alan M. Fryday, Nishanta Rajakaruna

Nishanta Rajakaruna

Geochemistry and mineralogy of rocks play important roles in the occurrence of individual lichen species and assembly of lichen communities. Whereas lichens of metal-enriched settings have been a focus of study for many decades, only a few such lichen inventories exist for North America. We reexamined the lichen biota of Pine Hill, a serpentine outcrop on Little Deer Isle, Maine and Callahan Mine, a copper- and zinc-enriched Superfund site in Brooksville, Maine by conducting additional field surveys and reexamining unidentified taxa from previous collections. To better characterize the substrates upon which the lichens were found, we conducted elemental analyses via …