Effect of a press wheel and depth of sowing on the establishment of semidwarf and tall wheats

1986 ◽  
Vol 26 (6) ◽  
pp. 697 ◽  
Author(s):  
BJ Radford

The effects of sowing with a press wheel on the seedling establishment of semidwarf (Banks, Cook, Shortim, 7605) and tall (Gatcher, Spica) wheats at various sowing depths (3.5-13 cm) were studied in factorial experiments in 14 sowings at 7 sites in Queensland. Establishment was generally lower with the semidwarf cultivars. A sowing depth of about 5.5 cm was optimum for wheat establishment when no rain fell between sowing and emergence. However, consistent placement of seed at the optimum depth requires level seedbeds or planting machinery with accurate depth control. Sowing with a press wheel increased the establishment of both semidwarf and tall cultivars at all depths of sowing. Semidwarf cultivars sown using the press wheel gave establishment equal to or better than tall cultivars sown without press wheel pressure. Highest establishment was obtained when tall cultivars were sown using a press wheel. The fitting of press wheels to wheat planters is recommended.

1987 ◽  
Vol 27 (4) ◽  
pp. 579 ◽  
Author(s):  
BJ Radford ◽  
GB Wildermuth

A factorial field experiment was carried out to determine the effects on barley establishment of 3 depths of sowing (45, 65 and 85 mm), 2 fungicide seed dressings (carboxin and triadimefon), a press wheel compared with a chain harrow, 2 cultivars (Prior and Grimmett), and the pre-emergence herbicide trifluralin incorporated prior to sowing. A laboratory experiment was also conducted to determine the effect of the 2 seed dressings on the coleoptile length of Prior and Grimmett at 20�C. The press wheel increased seedling establishment from 74 to 88% at a sowing depth of 45 mm, but from 55 to 89% at 85 mm. Carboxin seed dressing increased coleoptile length by 10-17 mm and triadimefon reduced it by 13-1 8 mm. Carboxin also gave better establishment than triadimefon when seed was sown deep. The cultivar Grimmett had shorter coleoptiles than Prior but slightly faster seedling emergence. The shortstatured cultivars now being bred for lodging resistance may also have short coleoptiles and hence poor establishment from deep sowings. The use of a press wheel improved establishment from a depth of 85 mm on a black earth soil. Incorporation of the herbicide trifluralin in the black earth soil 1 week before sowing did not affect establishment. A general lack of significant interactions meant that the main effects were usually additive, establishment increasing from 38% in the worst treatment (85 mm, triadimefon, chain harrow, Grimmett, no trifluralin) to 98% in the best (65 mm, carboxin, press wheel, Grimmett, trifluralin).


2015 ◽  
Vol 47 (1) ◽  
pp. 5-17
Author(s):  
Jolanta Korycka-Skorupa

Abstract The author discuss effectiveness of cartographic presentations. The article includes opinions of cartographers regarding effectiveness, readability and efficiency of a map. It reminds the principles of map graphic design in order to verify them using examples of small-scale thematic maps. The following questions have been asked: Is the map effective? Why is the map effective? How do cartographic presentation methods affect effectiveness of the cartographic message? What else can influence effectiveness of a map? Each graphic presentation should be effective, as its purpose is to complete written word, draw the recipients’ attention, make text more readable, expose the most important information. Such a significant role of graphics results in the fact that graphic presentations (maps, diagrams) require proper preparation. Users need to have a chance to understand the graphics language in order to draw correct conclusions about the presented phenomenon. Graphics should demonstrate the most important elements, some tendencies, and directions of changes. It should generalize and present a given subject from a slightly different perspective. There are numerous examples of well-edited and poorly edited small-scale thematic maps. They include maps, which are impossible to interpret correctly. They are burdened with methodological defects and they cannot fulfill their task. Cartography practice indicates that the principles related to graphic design of cartographic presentation are frequently omitted during the process of developing small-scale thematic maps used – among others – in the press and on the Internet. The purpose of such presentations is to quickly interpret them. On such maps editors’ problems with the selection of an appropriate symbol and graphic variable (fig. 1A, 9B) are visible. Sometimes they use symbols which are not sufficiently distinguishable nor demonstrative (fig. 11), it does not increase their readability. Sometime authors try too hard to reflect presented phenomenon and therefore the map becomes more difficult to interpret (fig. 4A,B). The lack of graphic sense resulting in the lack of graphic balance and aesthetics constitutes a weak point of numerous cartographic presentations (fig. 13). Effectiveness of cartographic presentations consists of knowledge and skills of the map editor, as well as the recipients’ perception capabilities and their readiness to read and interpret maps. The qualifications of the map editor should include methodological qualifications supported by the knowledge of the principles for cartographic symbol design, as well as relevant technical qualifications, which allow to properly use the tools to edit a map. Maps facilitate the understanding of texts they accompany and they present relationships between phenomenon better than texts, appealing to the senses.


Author(s):  
Beth Knobel

Perhaps no other function of a free press is as important as the watchdog role. It is easier for politicians to get away with abusing power, wasting public funds, and making poor decisions if the press is not shining its light with what is termed “accountability reporting.” This need has become especially clear as the American press has come under direct attack for carrying out its watchdog duties. This book presents a study of how this most important form of journalism came of age in the digital era at American newspapers. The book examines the front pages of nine newspapers, located across the United States, for clues on how papers addressed the watchdog role as the advent of the Internet transformed journalism. It shows how papers of varying sizes and ownership structures around the country marshaled resources for accountability reporting despite significant financial and technological challenges. Although the American newspaper industry contracted significantly during the 1990s and 2000s due to the digital transformation, the data collected in this book shows that the papers held fast to the watchdog role. The newspapers all endured budget and staff cuts during the 20 years studied as paid circulation and advertising dropped, but the amount of deep watchdog reporting on their front pages generally increased over this time. The book contains interviews with editors of the newspapers studied, who explain why they are staking their papers' futures on the one thing that American newspapers still do better than any other segment of the media—watchdog and investigative reporting.


1983 ◽  
Vol 101 (2) ◽  
pp. 435-440 ◽  
Author(s):  
T. O. Tayo

SUMMARYThe seeds of a dwarf variety of pigeon pea (cv. Cita-1) were sown at 2, 4, 6 or 8 cm depths in three field trials in 1981 and 1982, in order to evaluate the effect of sowing depth on seedling emergence and the subsequent growth, development and yield of the crop.In all trials, sowing pigeon-pea seeds deeper than 4 cm led to 1–2 days delay in seedling emergence, resulted in only 40–68% seedling emergence, reduced the development of the various growth and yield characters of the plant and significantly reduced seed yield. In two trials, plants from 4 cm sowing performed better than those from 2cm sowing in terms of development of growth and yield characters indicating that shallow sowing of pigeon pea prevents rapid and proper plant establishment.The results therefore indicate that the optimum sowing depth for pigeon pea is 4 cm under the prevailing lowland humid tropical conditions.


Author(s):  
Rui Zhang ◽  
Jiantao Wei ◽  
Tao Cui, Bingxin Yan, Xiantao He, Dandan Han, Li Yang

No-till planting can promote soil and water conservation and has gradually been adopted on the North China Plain where an annual wheat–corn double cropping system serves as the main cropping system. Corn is planted in June immediately after the winter wheat harvest so that fields are covered with wheat residues. The presence of wheat straw makes it difficult to maintain uniform corn seed spacing and sowing depth. To overcome these problems, a new seeder unit has been developed with a depth-control mechanism on a single-sided gauge wheel. A study was conducted to compare the performance of this seeder unit with two conventional seeder units (with depth-control mechanisms using double-sided gauge wheels and a rear gauge wheel) by testing in fields with two different amounts of residue (0.78 kg/m2 and 0.64 kg/m2). Seed spacing, sowing depth, and emergence time were measured after planting. The results indicate that the newly designed seeder unit with a single-sided gauge wheel performs better on seed spacing, sowing depth and emergence time uniformity, particularly in fields with a small amount of residue, with the quality of feed index, quality of sowing depth index and quality of emergence time index of 91.90%, 95.45% and 87.87%, respectively. The new seeder unit can meet the requirements of no-till planting for corn.


2010 ◽  
Vol 61 (11) ◽  
pp. 911 ◽  
Author(s):  
Nam-Jin Chung

Direct-seeding of rice on dry paddy soil could enable large-scale cultivation and cost-savings, but still has some problems including poor seedling establishment caused by low temperature and varied sowing depth. This research was performed to identify weedy rice genetic resources that may help to eliminate the problem of poor seedling establishment in direct-seeded rice on dry paddy soil in temperate regions. The genetic resources screened in this study were 128 genotypes consisting of 92 japonica weedy rices, 24 indica weedy rices, and 12 Korean bred cultivars. On average, weedy rice germplasm had superior abilities to emerge from greater depths than cultivated rices. Coleoptile and mesocotyl lengths were highly positively correlated with the emergence rate. Among the weedy rice germplasm, the japonica weedy rice WD-3 showed the highest level of emergence with the longest coleoptile and mesocotyl. The emergence ability of WD-3 was confirmed in both phytotron and field conditions. In the emerged plants in the field, the mesocotyl elongation increased with increasing burial depth in a logarithmic fashion, and coleoptile extension increased exponentially. The mesocotyl and coleoptile elongated to a length of seed burial depth, indicating that the mesocotyl and coleoptile of WD-3 could induce the safe development of the first leaf of the seedling at the soil surface. Therefore, the elongation habit of the mesocotyl and coleoptile of WD-3 could be one of the most important characteristics for the development of direct-seeding cultivars.


Author(s):  
John R. Dorrington ◽  
David G. Bogard ◽  
Ronald S. Bunker

Film cooling adiabatic effectiveness was investigated for various configurations of coolant holes embedded in shallow transverse trenches or circular and elliptical shaped depressions. As a basis of comparison, a shaped hole configuration was also tested. Tests were conducted on the suction side of a simulated vane at a downstream location where pressure gradient and curvature effects were small. For the transverse trench, effects of the trench width with varying depths, the trench wall angle, and the pitch between holes within the trench were investigated with trench depths that ranged from 0.5d to 1d. The crater depressions were tested at a depth of 0.5d. The film effectiveness for the crater depressions was not as good as the best performing trench configuration at that depth, but they all performed better than the baseline configuration of cylindrical holes. The trench configurations were found to have an optimum depth of 0.75d, with little improvement in performance for trench depths greater than this. Comparison of the trench performance with a typical shaped hole configuration showed that film effectiveness for the trench was similar to that of the shaped holes.


2011 ◽  
Vol 101-102 ◽  
pp. 551-555
Author(s):  
Fu Lan Wang ◽  
Hong Lei Jia ◽  
Dan Dan Liu

Pressing is an important part of precision seeding operation, which has an important effect on crushing soil. In order to enhancing the effect of soil crushing, some press wheels with flange rim are used. But further research is needed to evaluate whether the use of these press wheels affect the actual seeding depth that will affect precision seeding quality. Three kinds of press wheels, with the smooth rim, circular flange rim and rib rim respectively were designed, and the PFC3D discrete element method (DEM) software was used to simulate the pressing processes of these press wheels, and the contact force between the rim and soil, soil displacement and porosity were analyzed. It was concluded that the press wheel with the smooth rim is better than others in precision seeding operation.


Author(s):  
Berry Craig

The secessionists and their allies in the press chafed under neutrality. They charged that the unionists were using neutrality as a cover to build support for entering the war on the Union side. The secessionists suffered another hard blow at the polls on June 20, when unionist candidates won nine of Kentucky’s ten seats in the congressional elections. The Southern sympathizers and their newspaper friends pinned their last hopes on the August elections for the state legislature, in which all 100 house seats and half of the 38 senate seats were on the line. Meanwhile, as chances for a Confederate Kentucky melted in the summer heat, some Confederate papers cooled their secessionist ardor and seemed to acquiesce in neutrality, at least for the time being. Neutrality, they reasoned, was better than fighting for the North. But the secessionists stuck to their argument that the “Black Republicans” would destroy slavery and make African Americans and whites equal in Kentucky. The Union Party won its biggest victory yet in the state elections. Thus emboldened, the unionists supported Camp Dick Robinson, a recruiting station for Union army volunteers in central Kentucky. The state was on the verge of abandoning neutrality and fully embracing the Union war effort.


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