CUTTER CMS, LLC

ACQUIRED BY GRO ALLIANCE

Gary L. Cutter, Ph.D.

Corn Cytoplasmic Male Sterility Conversions Made Genetically Pure in 2-3 Generations

(Web site information updated 11/24/2018)

Service Offered:

Since October 2011, Cutter CMS, LLC has provided a service to the seed corn industry of developing cytoplasmic male sterility conversions of corn inbred lines used as females in seed production by using a unique efficient technique. The use of such male sterile female parents significantly reduces the costs of seed production by (1) reducing or eliminating the costs of detasseling, (2) increasing seed yields from 15 to 30% as compared to mechanically detasseled seed production, (3) reducing the risks of insufficient detasseling labor and weather influences, and (4) decreasing the exposure to safety incidents due to detasseling by hand.

Since beginning the service 7 years ago, a total of 154 projects (inbred/cytoplasm combinations) have been entertained from 11 clients.

In June 2018, Gro Alliance, a seed corn and soybean production company with seed corn nursery services, acquired the assets and intellectual property of Cutter CMS, LLC and began the process with new clients. (See the press release at this link).The agreement allows Cutter CMS, LLC to continue work with its present clients until 2023, after which these clients will be served by Gro Alliance. A two year training of the process is being provided followed by availability for consultation for subsequent years. Any new inquiries will be handled by Jim Schweigert of Gro Alliance at jim.schweigert@groalliance.com.

Technique Used:

The conversion technique used is the “indeterminate gametophyte (ig) system” involving paternal haploids and cytoplasmic male sterility. Significant advantages of the results of this conversion technique include:

Experience of Gary Cutter, Ph.D., Owner and Corn Breeder of Cutter CMS, LLC:

Gary retired in 2011 with over 36 years of experience in the seed corn industry with a major seed company in the areas of corn breeding, research station and regional management, corn seed production research, male sterility conversions and parent seed management. He had been involved with the “ig” male sterility conversion system since the mid 1970’s when Dr. John Laughnan provided the initial genetic stocks to the industry corn breeders during the Illinois Corn Breeders School. There have been inbred conversions from his development programs that have been used significantly in the industry during the past 20 years.

Gary earned a Ph.D. in Plant Breeding and Genetics at the University of Wisconsin-Madison after earning BS and MS degrees in Ag Education and Agronomy, respectively, at Purdue University. He continues to be a student of the “ig” technique and has been developing efficiency improvements to the system. Gary started this business after his corporate retirement because he enjoys the outdoor field nursery work, seeing the value added results of an inbred male sterile conversion going through the paternal haploid stage and adding value as a perfect genetic and phenotypic recovery without using molecular methods.

How the “ig” Male Sterile Conversion System Works:

The system utilizes the effects of the “ig1” gene on the abnormal development of the female gametophyte in the W23 genetic background. Progeny of a cross of an inbred to be converted as a pollinator on the ig stock will include a low percentage of haploid plants, about 2/3 of which are of paternal origin genetically. The stock used as the female in the cross includes the male sterile cytoplasm which will be inherited maternally by the paternal haploids; thus these paternal haploid plants will carry 100% of the pollen donor’s nuclear genome along with the male sterile cytoplasm. These haploid plants are then backcrossed as the female to the donor inbred and due to chance a few kernels are generally produced. Nearly all these kernels originate from a few “unreduced female gametes” that occur by chance during meiosis in the haploid plant. Nearly all of these kernels are viable and grow as diploid plants and are identical phenotypically and genetically to the donor inbred with the desired exception of being male sterile due to the cytoplasm genetic effects if the donor inbred does not carry restoring genes. These are the plants that are increased during the 3rd generation of the process, where the phenotype and male sterility is verified. Of course the increase of the male sterile plants is done by crossing with the original inbred being used as the “maintainer”.

Service History and Success Rate (as of 11/23/2018):

Since beginning the service in 2011, a total of 154 projects (inbred/cytoplasm combinations) have been completed or are in progress from 11 clients. A total of 33 of these projects are presently active, undergoing either the first, second or third generation of the process. Clients have the option of dropping a project before the planting date. Of those projects that have not been dropped, 97% have been completed; 81% were completed during the 3 generations planned. Delays of completion have been primarily due to no paternal haploids being produced or failure to set viable seed on the paternal haploids due to silking, insect or disease problems.

Options, Timelines and Fees of the “ig” CMS Conversion Service

The conversion process may be started either in the off-season or summer nursery. However, the second generation of the process must be done during the home summer nursery because of the attention to detail necessary in identification, pollination and care of the paternal haploid plants. If the process is begun in the off-season nursery, then it can be finished in three consecutive growing seasons (off-season, home, and off-season) with seed of the completed conversion provided for a spring planted increase by the client. If the first generation of the project is done during the summer, the second generation will still be done the following summer. This would result in two years to completion instead of 1 ½ years. As noted earlier, over 80% of the time seed of the conversion is generally provided after 3 generations. The remaining projects may need to have the second generation repeated due to lack of seed set on the paternal haploid plant or insect or disease damage to the seed set on the haploid plant.

Following is a description of each of the 3 generations of the process:

First Generation: For each inbred the client will provide the following by November 15 (or April 15 for summer nursery):

Second Generation:

Third Generation:

Summary of Fees: New conversion projects will be handled by Gro Alliance. Their total charge for the conversion of an inbred is $10,000, of which $2,500 is for initiation, $3,500 for the second generation planting, and $4000 before the return of seed increase after the third generation. This includes one or both cytoplasm conversions (C and SD) of the same inbred where it does not have residual restorer genes identified by the testcross grow-out. If the conversion is not completed due to the choice of the client or the presence of restorer genes, only the first and/or second generation charges are applied.

Additional Considerations:

Contact Information:

Cutter CMS, LLC
Gary L. Cutter, Ph.D.
Cell phone: 1 (309) 825-5149
Email: gary@cuttercms.com

Gro Alliance Jim Schweigert
Cell Phone: 1 (608) 732-8459
Email: jim.schweigert@groalliance.com