Plant breeding is the method of crossing two different plants to obtain specific phenotypes from the offspring. This is done through controlled pollination or open pollination. Controlled pollination is done by harvesting pollen from male flowers with the use of tools such as paint brush. The harvested pollen is then delivered to specific female flowers. This method is best when you want to use multiple male plants to a single female plant. Each female flower is labeled with from which male plant was dusted.
Open Pollination is having one male plant to flower in a room full of female plants. This method has greater chance for the female plants to be seeded. In order to create different variety, multiple female plants are introduced.
The goal of crossing plan breeds is to introduce a traits from variety to new genetic pool. For example one plant have high quality of crop but has very low yield and another plant variety has high yield but with a low quality of crop. We cross the two plants in the hopes of achieving a variety with high quality of crop with high yield. Although this is not easy to achieve. The outcome of this cross breed are called F1 hybrids. This means that they are first generation of the cross. If a hybrid shows promising results then it will be further breed to stabilize and enhance the genetic trait.
F1 hybrids are known to be more vigorous than the parent plants. F1 hybrids also show little variance from seed to seed and will usually share a common dominant trait. Crossing F1 hybrids will results in an F2 hybrid that will then show more variance from seed to seed. Cross breeds after the F2 hybrids is the time where more and more recessive weak traits show up. Careful selection of F2 hybrids is necessary to get the desired result.