Hybrid agricultural and horticultural crops can play an important role in supporting global food security. They produce higher yields and are often more resistant than non-hybrid varieties to diseases and climate stress. Maize is a globally very important crop and the use of hybrid varieties is routine. The first type was introduced as far back as 1930. But that hasn’t happened for other major crops such as wheat and cassava. A comprehensive study has been done of all the factors that determine whether commercial plant breeders can come up with a hybrid variety. Sometimes there are biological challenges.
It’s a uniquely comprehensive survey published in the journal Nature Plants. The authors of the article are associated with hybrid potato breeding company Solynta and Wageningen University & Research. The lead author is Emily ter Steeg who is a Ph.D. candidate in development economics.
Generating inbred lines
There are many obstacles to overcome. It needs to be biologically possible to produce those homozygous parental lines. A self-pollinating plant is ideal. It is much harder for plants that always cross-pollinate with another plant. Some crops also have multiple sets of chromosomes which makes it even harder to produce inbred parent lines. The potato grown on our fields have four sets of chromosomes with hereditary material. That’s an important reason why there have been so few attempts to generate inbred lines. It makes potato breeding particularly difficult and that’s why we still have ancient varieties like the Bintje or Russet Burbank.
But we’re making progress. There are in fact also diploid potatoes that have just a single set of genes. These varieties did not support inbreeding. But scientists at Solynta and Wageningen University & Research have recently managed to get around that obstacle. The Sli gene is the key to that. Now the path is clear to develop potatoes from hybrid seeds rather than from tubers.