The effects of root exudates of two sunflower cultivars (Shumoose and Sin
Altheeb) were studied on companion weeds during the growing season of 2012.
Results showed the ability of both cultivars to affect weed population and growth
with the superiority of cultivar Shumoose in suppression of weed density at 60 and
120 days after sowing compared to Sin Altheeb. Weed biomass was significantly
reduced up to 90 and 71% by Shumoose and Sin Altheeb cultivars, respectively.
Stair case experiment indicated that root exudates of Shumoose cultivar showed
more suppression to weeds than Sin Altheeb giving additional evidence for the
superiority of Shumoose cultivar in its allelopathic weed suppression. Chemical
analysis by High performance liquid chromatography indicate the presence of nine
compounds in root exudates of Sin Altheeb and eight compounds in Shumoose, and
all are Phenolic in nature with differential concentrations between these cultivars Most of the isolated chemicals known for their inhibiting ability for germination and
growth of plants, including weeds. Total of the isolated phenolics was doubled in
Shumoose than in Sin Altheeb.
The experiment was conducted at the period from 20th Dec. 2015 to 30th Mar. 2016 to know the effect of growth medium and nodes number on the acclimatization success of tissue propagated potatoes seedlings (Burrin class) and study some plant physiological properties. The first experiment involved testing growth media: loam, peat moss, and perlite with different portions (1:1) to plant tissue propagated potato tubers, while the second experiment involved testing the nodes number where 9, 8, 7, 6, and 5 plant nodes were chosen. Results of the first experiment showed the superiority of the culture media of peat moss + perlite to other culture media by giving the higher values of shoot system studied properties: plant height, branches number, le
... Show MoreThis study investigated the effect of using brainstorming as a teaching technique on the students’ performance in writing different kinds of essays and self regulation among the secondary students. The total population of this study, consisted of (51) female students of the 5th Secondary grade in Al –kawarzmi School in Erbil during the academic year 2015-2016. The chosen sample consisted of 40 female students, has been divided into two groups. Each one consists of (20) students to represent the experimental group and the control one. Brainstorming technique is used to teach the experimental group, and the conventional method is used to teach the control group. The study inst
... Show MoreOne of the most important problems in tablet process is to control the flow of the catalyst through the hopper; Controlling the flow can be done either by changing the size of particles or added the different lubricant (stearic acid, starch, graphite) or blending of different lubricants. The study showed that we can control (increase or decrease) on the flow of the catalyst through the hopper by blending different lubricants for the constant percentage. The flow increasing when particles size (0.6 mm) and then decrease with or without lubricants, no effect on flow when particles size lower than (0.2 mm) with use that lubricants, and good flow on (0.4 mm) when use stearic acid and starch.
Obliquely deposited (70o) Bi, Sb, and Bi-Sb alloy thin films have been prepared by thermal
resistive technique. Structural properties of these films were studied using XRD. Their resistance and
voltage responsivity for Nd:YAG and CO2 laser pulses have been recorded as function of operating
temperature between 10 oC and 120 oC. It was found that the maximum responsivity for these detectors
can be obtained at 75 oC. On the other hand, the dependence of responsivity on the width of detectors was
investigated.
In this experimental and numerical analysis, three varieties of under-reamed piles comprising one bulb were used. The location of the bulb changes from pile to pile, as it is found at the bottom, center, and top of the pile, respectively.
Copper oxide thin films were deposited on glass substrate using Successive Ionic Layer Adsorption and Reaction (SILAR) method at room temperature. The thickness of the thin films was around 0.43?m.Copper oxide thin films were annealed in air at (200, 300 and 400°C for 45min.The film structure properties were characterized by x-ray diffraction (XRD). XRD patterns indicated the presence of polycrystalline CuO. The average grain size is calculated from the X-rays pattern, it is found that the grain size increased with increasing annealing temperature. Optical transmitter microscope (OTM) and atomic force microscope (AFM) was also used. Direct band gap values of 2.2 eV for an annealed sample and (2, 1.5, 1.4) eV at 200, 300,400oC respect
... Show MoreA two-year study (harvest years 2019 and 2020) was conducted to investigate the effect of a commercially available biofertilizer, in combination with variable nitrogen (N) rate, on bread baking quality and agronomic traits in hard winter wheat grown in conventional (CONV) and organic (ORG) farming systems in Kentucky, USA. The hard red winter wheat cultivar ‘Vision 45’ was used with three N rates (44, 89.6 and 134.5 kg/ha as Low, Med and High, respectively) and three biofertilizer spray regimes (no spray, one spray and two sprays). All traits measured were significantly affected by the agricultural production system (CONV or ORG) and N rate, although trends in their interactions were inconsistent between years. In Y2, yield was
... Show MoreIn the present work, the effect of isolated dust particles (FeO) with radius of the grain 0.1μm - 0.5μm of main plasma characteristics are investigated experimentally in direct current system by using magnetic field. The present of dust particle in the air plasma did effect on Paschen minimum and on the plasma properties in low pressure region. The effect of dust particles on discharge voltage, discharge current, plasma potential, floating potential, electron density, electron temperature and Debye length was investigation by using magnetic field. The measurements of parameters are taken by four cylindrical Langmuir probes. The results show the present of dust causes decreasing in discharge voltage with increase pressure while the disc
... Show MoreThe problem of the research lies in finding aiding means that improve and facilitate learning artistic skills during the main part of a teaching sessions due to their great importance in developing the accuracy of forehand and backhand skills in tennis. Players are usually faced with difficulties at the beginning of learning due to lack of coordination in ball striking thus including a teaching aid will have a positive effect on learning some forehand and backhand skills. The research aimed at designing exercises using teaching aid in tennis as well as identifying the effect of these exercises on the accuracy of performing forehand and backhand shots in tennis. The researcher used the experimental method on (38) tennis players from Al Zewra
... Show MoreA pots experiment was conducted in the plastic house of Kalar Horticulture station Province of Sulaimania, by using soil brought from one of Kalar region fields during growing season of 2007-2008, to study the effect of increasing levels of urea fertilizer which is (0, 0.20,0.40,0.80) g/pot which equals to (0,100,200,400) kg urea/ha, and super phosphate fertilizer which is (0,0.24,0.48)gm/pot which is equal (0,120,240) kg sup/ha, in nutrition state of wheat IPA 95 component, clay determining Nitrogen, Phosphor and Potassium content in green part and seeds. The Completely Randomized Design was used with three replication per t
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