Plant genetics and cross breeding

Plant genetics and cross breeding

Introduction

The aim of today's plant breeders is different from that in the broad sense are not the first farmers 10,000 years ago. Then as now, the farmer wants resistant and high yielding crops. The breeding methods, however, were expanded.

In the genetic material of all living things - including plants in - it always comes back to natural changes (mutations). These mutations lead to lose that plant will also, over time, new or old properties. Since time immemorial man uses these naturally occurring mutations and breeding new varieties by plants with desired characteristics chooses, and increasingly crosses with other plants. For example, all our crops originate from wild grasses or the plum from a cross between the wild plum and cherry plum.

The natural variation of the genome is a very slow process. To speed it up, the plant seed is treated with chemicals or some radioactivity. This increases the frequency of mutations and thus the likelihood that the plants acquire new desirable properties (Janick, 2010).

Discussion

Genetic Engineering

Using genetic engineering it is now possible to target gene transfer to modify and beneficial properties of plants (for example, to make it to a particular insect resistant).The transferred gene must not necessarily be a gene from another plant, it can also consist of a bacterium, fungus, virus or animal derived. This insertion of alien genes differs genetically engineered crops by conventional breeding methods.

1983 succeeded in breeding the first genetically modified (or transgenic) plant. Today, almost thirty years later, there are many important crops and transgenic varieties that are grown in some large scale. These include corn, potatoes, canola, soybeans and cotton.

In U.S., however, may for the time being no GM crops are grown. This was decided by the Swiss people in a referendum in 2005. The moratorium was extended until 2013. Meanwhile, studies the National Research Program "Benefits and risks of genetically modified crops" (NRP 59), the pros and cons of genetically modified plants. In addition to the risks, there are also ethical concerns about genetically modified crops (Sleper & Poehlman, 2006). 

Resistance to harmful organisms

Plants can be genetically modified so that pests can harm them less. The aim is to increase the yield of the crop. One thing is clear: If plants can defend themselves against harmful organisms, must inject the farmer less pesticide.

Example:

Corn with insect resistance to the bacterium Bacillus thuringiensis (Bt) produces a toxic protein that is lethal to certain insect larvae. When the larvae eat the bacteria that poison holes drilled into the gut of the larvae - which makes them starve. Genetic engineers have succeeded in transferring the Bt gene in these plants and thereby confer protection against insect larvae. Thus, for example, corn plants can protect against the European corn borer. Critics voiced their doubt that the toxin could also act on other, non-dangerous animals to the plant. The so-called Bt corn is grown over a large area in the Americas and Africa. In Europe there are large areas under cultivation, particularly in Spain.

Following a similar principle as presented here, Bt corn have been as potatoes or sugar beet fungal resistance to viral resistance developed by genetic engineering methods, and especially ...