Horticultural and hybrid crops could play an important role to support global food security. The yield is higher and are often more resistant to climate fluctuations and diseases than non-hybrid varieties.
But, hybrids are not available for many crops. What could be the reason?
Globally, maize is an important crop for which hybrid varieties is routinely used. The first hybrid variety of maize was introduced in 1930. But major crops such as cassava and wheat have not witnessed a range of hybrid varieties.
For the first time, a comprehensive study has now been undertaken covering all factors that determine if commercial plant breeders can come up with a hybrid variety. Economic factors often come into play. Biological challenges are there sometimes.
The uniquely comprehensive survey is published in Nature Plants.
Scientifically, a hybrid variety is obtained by combining two parental plants that complement each other perfectly. The hybrid includes the best qualities of the parents.
Nonetheless, this requires parents to be genetically uniform as much as possible. With the process called ‘selfing’ this can be done by crossing parents.
Meanwhile, to develop strong parent lines in cost and time intensive. This requires the plant breeder to be confident of handsome return on investment.
Importantly, this requires many obstacles to be overcome. First, biologically it needs to be possible to produce homozygous parental lines. This makes self-pollinating plants to be ideal, and is much harder for plants that always need cross-pollination with another plant. Besides this, some crops also have multiple sets of chromosomes, which makes it even harder, or nearly impossible to generate inbred parent lines. For example, the potato that grows in fields has four sets of chromosomes with genetic material.