IV. MAIZE GENETICS COOPERATION STOCK CENTER

The Maize Genetic Stock Center would like to have some feedback concerning the needs of the cooperator community and our ability to satisfy them in the past few years. We have distributed over 2,300 packets this past year in response to over 150 different requests. We try to provide the materials as close to the requested material as we have on hand.

On 10 December 1985 we sent out approximately 180 letters to Cooperators asking them for specific information concerning the service that the Stock Center has provided in the past. Approximately 20 percent have already responded. For this we are grateful and many very useful suggestions have been made that we will attempt to incorporate in our future operations. The main concern mentioned is the furnishing of homozygous materials. This is a tough nut to crack.

One clarification is important. The items listed in the stocklist in the past have only indicated that we have stocks that contain the mutants indicated. It has never meant that all of those items were available in a homozygous condition nor in a variety of inbred backgrounds. Many of the mutants such as the viviparous group can not of course be provided in a homozygous condition. Others such as brittle are difficult to maintain in a homozygous state. The best results in general are obtained by crossing the stocks to a vigorous and suitable hybrid and then selfing this to get a segregating stock that provides reasonable quantities of more robust plants. Recently the needs of physiologists and genetic engineers have put a premium on providing known homozygous mutants in known inbred backgrounds. At present about the only stocks available in particular inbred backgrounds are endosperm traits, male steriles, virescents and glossies. We are underway with the project discussed at the March 1984 meeting of developing pairs of good markers in both arms of all 10 chromosomes. This summer was the second one in this program and progress has been good thus far.

In order to meet the needs of these specialized researchers we are attempting to expand the numbers of stocks that are available in the homozygous condition and in known backgrounds. This is an enormous project which makes our work more difficult as well since the known homozygotes often produce very poor ears. We will publish two stock lists this year, the major one listing, as in the past, all stocks that we can furnish which will contain the desired mutant and if it is in a segregating material we will insure that you should get at least 12 kernels that carry the desired trait or traits (in a 1:1 ratio we will send at least 24K, in a 3:1 at least 48). The other stocklist will list those stocks that we can furnish in a known homozygous condition. In future years we will attempt to expand the listing and provide information on inbred backgrounds where this can be done. This project will run parallel to the selected pairs of markers in selected inbreds mentioned earlier.

At the present time we are updating the entire computerized inventory to enable us to extract information on the homozygous condition and backcrossing information on all of the stocks. This should be a big project.

We have received some new stocks from Missouri this year and we are anxious to add any and all genetic materials that wuold be of use to the cooperators in general.

As Ed Coe has mentioned in his annual notice, we are trying to do the best job possible here at the Coop. If you have been dissatisfied with the materials please let us know. Both Jerry Chandler and I are anxious to improve the performance and the utility of the Coop stocks and to ameliorate the administrative procedures.

Gilbert B. Fletcher, Director MGCSC, Department of Agronomy, University of Illinois, S-123 Turner Hall, 1102 S. Goodwin Avenue, Urbana, IL 61801, Phone (217) 333-9644, Lab (217) 333-6631