Dissolve corn is to release a body that produces an immature pollen, fringe, from the top of the corn crop (corn) and place it on the ground. It is a form of pollination control, used for crosslinking, or hybridization, two varieties of maize.
The cornfield to be dismantled is planted with two varieties of maize. Each corn plant has a male and female portion, so if both corn varieties are left intact, some of the seeds produced will have a non-hybrid parent. Removing the tufts from all the plants of one variety leaves the grains growing on the plant to be fertilized by another tassel, producing a hybrid.
In addition to being more physically uniform, hybrid corn produces much higher yields than corn produced by open pollination, as well as other desirable properties, such as disease, drought, and weather resistance. With modern corn seed varieties for hybridisation are carefully selected so that new varieties will show the special features found in both parent plants. The process of detasseling usually involves the use of specialized machines and human labor.
Video Detasseling
Muffle engine
Almost all detasseling is done in two steps; field was first unloaded by machine and then dismantled manually. The hacking machine itself is usually a two-step process. Originally a detasseling machine called a "cutters" passed the corn line to be dismantled and cut off the top of the plant. This is done to make the fields more uniform so that the "towing machine" can then come through the cornfield as the tassels begin to appear past the cut leaves and pull the fringes out of the plant. It usually takes 24 to 48 hours to get the tip of the tassel enough to get a good pull without holding the leaves of the plant after the initial cut. The towing works by capturing the top of the tassel between two rollers moving at high speed. This eliminates most of the tassels.
The detasseling machine typically removes 30 to 90 percent of the tassels in the seed corn field. This is much smaller than the 99.7 percent that need to be removed to produce the uniformity of seeds desired by farmers. The main problem for machines is that they can not adapt quickly to plant height differences and they throw a tassel into the air where they can get caught in other corn crops and inadvertently allow pollination. It is desirable that the retractable tassels end up on the ground to prevent this problem.
Maps Detasseling
Manual cleaning
Whether or not a field of corn seeds was initially dismantled by the machine, people were eventually hired to overhaul the plants that the machines missed and to remove the tufts left by the machines in the leaves of other corn crops. This is done either by having "detasselers" running through cornfields removing tassels or by having the detasselers ride through the cornfields on the carrier detasseler. The detasseler carrier is usually used when corn is too high to be dismantled from the ground. Each operator can withstand eight to twelve detachers.
Detection work is usually done by adolescents; thus, it serves as a typical rite of passage in the countryside of the Corn Belt of the Midwestern United States. (Byron 2002) (Gustafson 2003) For many teenagers in this field, this is their first job. The exact start date depends on the country-specific region and growth conditions of any given year. The "seasons" that typically last from two to four weeks on weekdays vary from just a few hours to more than 10 hours depending on the growing season. Wages for detasseler vary greatly; some detasselers get a minimum wage while others earn more than $ 12.00 per hour. Individual wages depend on corn seed companies, detachment contractors, detachment experiences and even individual field conditions such as number of plants per acre, percentage of tassels pulled by a detasseling machine or corn elevation.
The way in which wages are determined can also vary greatly between contractors who do extermination. Some pay hourly wages instantly, others pay in units per piece in which the detasselers are paid a sum for each row, panel or acre dismantled. Other contractors use a ranking system to determine the wage of a detachor for a given day.
In addition to employing large teenagers, some areas of the country employ migrant workers as detasselers. Wages of migrant workers are usually paid on the basis of wage per unit. During the 1980s in some areas the US detection work shifted from being a local teenager especially to a migrant farm worker.
History
The beginning of the 20th century
Detasseling was used in the late 19th and early 20th centuries in the "ear-row" method of corn breeding. In this method the rows of corn alternated and the seeds of the dismantled row are stored for planting the following season. However, ear-line breeding does not result in a large increase in yield and is largely abandoned after a few years. (Wallace 1925, pp. 223)
Around 1910 experimental maize farmers became energized by the possibility of increasing the yield of corn by traversing two superior varieties. Again, this is done by planting varieties in alternating rows and removing any of the varieties. This seed production method also proved disappointing and also abandoned. (Wallace 1925, pp.Ã, 224)
However, a modern hybridization process, in which one inbred path of maize is crossed with another, developed from early work in cross-breeding. In 1908, George Harrison Shull described heterosis, also known as hybrid power. Heterosis describes the descent of a specific cross to outperform both parents. In 1917, a process was developed that would make this hybridization commercially viable. In 1933 less than 1% of maize produced in the United States was produced from hybrid seeds; in 1944 more than 83% were. (Copeland 1995, pp. 236) This hybrid seed is produced by crossing two congenital lines by planting a single line of inbred varieties followed by several lines of second variety. The tufts of the second varieties are removed by hand so that the second variety can be pollinated by the first.
End of the 20th century
Hybrid corn was dismantled manually until the mid-1950s when the cytoplasm was discovered which would cause one of the inbred lines to become sterile males while the hybrid corn seeds produced would regain male fertility. This gene allows corn seed companies to reduce their labor costs by producing corn seeds without the need for manual detasseling. In the mid-1960s almost all corn kernels were produced with this gene. (Basra 1999, pp.Ã, 52)
This situation changed in 1971 with the outbreak of southern corn leaves. The cytoplasm used to produce male sterility is highly susceptible to this fungus. At that time about 90% of the hybrid corn used in the United States contained this gene. (Smith 2004, pp. 601) About 15% of corn crops are lost due to infection and over the next few years male sterility is abandoned and almost all corn seeds are again dismantled manually. (Copeland 1995, pp.Ã, 238)
In the mid-1970s, machines were developed to help reduce large manpower costs associated with manual blurring and in response to the declining workforce of rural youth. In the 1980s the sterile male varieties were reintroduced that were not susceptible to southern corn blight, but the dependence on single sterile varieties seen in 1960 has not been repeated. (Basra 1999, pp.Ã, 51-52)
Currently corn hybridization is achieved with a combination of decadent engine and manual as well as sterile male genes.
Field of corn seed
The cornfield seeds are planted in a repeating pattern known as "panel", "block", "frame", "bay" or "set" depending on the area of ​​the country. There are two main cropping patterns for this panel. A panel can be planted in a 6: 2 pattern in which six "female" lines, lines to be disassembled, followed by two "male" or "bull" lines, lines that will be used to pollinate the damaged lines. Panels are also usually planted in a 4: 1 ratio with four female lines followed by one male line. Other less commonly used patterns also include 4: 2 and 4: 1: 6: 1. In all cases, the pattern continues throughout the cornfield. (Smith 2004, pp.Ã, 584)
Source of the article : Wikipedia
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