Bright Future for Sorghum Hybrids

Sorghum growers can expect more choices in grain sorghum hybrids in 2020 than in previous years. There are many new grain sorghum hybrids that have been released by seed companies this year, and that is on top of several new hybrids released in 2019.

Article by Brent Bean, Sorghum Checkoff

Sorghum growers can expect more choices in grain sorghum hybrids in 2020 than in previous years. There are many new grain sorghum hybrids that have been released by seed companies this year, and that is on top of several new hybrids released in 2019.  These new hybrids are not limited to certain regions, but most growers around the U.S. will have access to a new hybrid or two to try on their farm.  Generally, in the first year of release, seed supply will be limited, but growers should take the opportunity to plant a few acres of new hybrids to compare to what they have been planting.

Seed companies spend a lot of time evaluating sorghum hybrids before they are made commercially available and will not bring them to the market unless they have some significant advantage over other hybrids that they sell. Higher yield is always the goal and can be accomplished in basically two ways. The first is through parent selection and heterosis that results in better yield potential under optimum conditions.  The second way is through better defensive traits.  These defensive traits equip the hybrid to better withstand abiotic (nonliving) and biotic (living) stress.

Abiotic stress is typically caused by drought and high temperatures. Since sorghum tends to be grown in dry environments, sorghum breeders spend a large portion of their efforts in developing hybrids that can withstand periods of drought and still maintain yield potential. Often overlooked by growers is the importance of heat stress. Much of the Sorghum Belt has experienced elevated temperatures the last few years, and this is not expected to change any time soon.  More effort is going into breeding for heat stress than in the past.

Biotic stress is usually from insects, diseases or weeds. Since the infestation of U.S. sorghum with the sugarcane aphid in 2013, seed companies have worked to identify hybrids and parent lines with sugarcane aphid tolerance. Many of the new hybrids being released in 2020 have superior sugarcane aphid tolerance while maintaining or even increasing yield potential.

For those regions where diseases are an issue, better anthracnose resistance has been incorporated in some of the new hybrids.

Although we will not see any new hybrids with herbicide tolerance on the market in 2020, sorghum growers in 2021 and 2022 may very well have three different herbicide traits to choose. Hybrids are in the pipeline with ACCase, sulfonylurea and imidazolinone tolerance to aid in weed control. Field demonstrations are being planned with these technologies in 2020.

The rate at which new sorghum hybrids have come to the market has lagged behind many of the other crops. For example, it is not unusual for a corn grower to make a hybrid change every 3-4 years. One of the reasons for this is that corn and some of the other crops have greatly benefited from what is called double haploid technology.

This technology was discussed in detail in the Summer 2019 edition of the Sorghum Grower magazine and can be accessed at SorghumGrowers.com. Due to a large investment of grower dollars, through the United Sorghum Checkoff Program, sorghum is well on its way to having this technology. The result for growers will be that breeders will soon be able to reduce the time in half that it takes to develop new hybrids. And just as importantly, breeders will be able to screen many more parent line combinations for hybrids than they currently are able to screen.

Research the last few years has brought a wealth of knowledge of the DNA of sorghum. The entire DNA of an organism is called its ‘genome.’  Breeders working with molecular biologists now have a much better map of where key genes are located in a sorghum plant’s genome.  By using this knowledge, along with computers and statistics, breeders are able to make better predictions on the outcome of crossing two parent lines.  The term given to this technology is called genome-wide association studies (GWAS).  In other words, GWAS should take a lot of the guess work out of developing new hybrids.  This in turn should lead to not only better, but faster, development of sorghum hybrids.

Although all of the new technologies that are coming to sorghum are not going to be implemented over night,  because of them, the future looks bright for new and better sorghum hybrids this growing season and in the coming years.

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