Higher yields are always a top priority for plant breeders developing new crop varieties, but yield itself is the result of a combination of different factors, including resistance to disease threats, maturity timing, and harvestability.
These characteristics are all taken into consideration when screening and developing new edible bean varieties, explains Anfu Hou, bean breeder at Agriculture and Agri-Food Canada’s Research and Development Centre at Morden, Man., in this Edible Bean School episode.
When it comes to increasing disease resistance, bacterial blight, anthracnose, sclerotinia (or white mould), and root rots are the main targets for Hou’s team in Manitoba.
“When we talk about the genetics, some traits are controlled by single genes. It’s one gene, you’re good with it. Anthracnose resistance, you introduce that gene, you’re good. But there are traits, like a root rot, like quality traits, they are controlled by multiple genes, and they are often affected by environment. So those, like white mould resistance, are very difficult to to work with,” he explains.
For bacterial blight, which was a common challenge for edible beans in Manitoba in 2022, there were no good sources of resistance in domesticated bean genetics, so breeders turned to wild species to develop a navy bean variety with bacterial blight resistance and bring it to market several years ago, he notes.
“It’s a very good addition to production, and it’s very good breeding material now that many people are using,” says Hou.
At the end of the growing season, pods that are on the ground or difficult to harvest also hurt yield potential, so breeders have focused on developing more upright varieties that can be direct harvested. This also results in savings on labour cost, not having to cut or windrow beans in separate field passes.
“If you look at varieties today in the bean trials, they are more upright than they used to be. There are still very bushy varieties, but for direct harvest, for help with managing the cost, we pay a lot of attention to selecting those more upright types,” says Hou.
Check out the video below for more on what edible bean breeders and researchers like Anfu Hou are focused on (filmed during the Manitoba Pulse and Soybean Growers’ 2022 edible bean tour at AAFC Morden):
Find more Edible Bean School episodes here.