During calendar 1991, 2985 seed samples were provided in response to 229 requests. As part of these totals, 535 samples were supplied in response to 44 requests from 21 foreign countries.

There were periods of severe drought during the summer that, in spite of irrigation, prevented adequate seed increase of numerous genetic stocks that lack vigor or ability to withstand stress conditions. Significant portions of all plantings will need to be repeated.

An important component of the summer's plantings consisted of selected stocks that are in low supply. In addition, there were plantings of newly submitted symbolized stocks and of newly acquired untested stocks. There were specific efforts to increase and improve stocks of chromosomes 2, 3, 7 and 8. There was a special increase of goldens, pale greens and yellow-stripes.

There were greenhouse sandbench plantings to determine or confirm genotypes relative to seedling traits. Observation field plantings were also grown to derive similar information relative to mature plant traits.

Catalog items change from year to year, so requests should be based on the latest listing. In making requests, you should indicate both the code number and the genotype of each stock. This information allows us to recognize typographical errors in some cases, or to seek verification of intent when these two types of information are in conflict.

It is sometimes necessary to discontinue supplying samples of particular listed items because of insufficient seed supply or because of detected pedigree errors. In these cases, we attempt to substitute stocks with closely similar genotypes.

We wish to re-emphasize that if you submit genetic stocks to our collection that involve traits that require special techniques, facilities or skills for classification (e.g., isozyme variants), the stocks should be homozygous for the designated alleles. In that way, the samples may be propagated by selfing, sibbing or intercrossing without the necessity for classifying segregating progenies. We hope that greater diagnostic capabilities may become available to us in the future.

We expect that during the next several months a Research Geneticist will be employed by USDA-ARS who will, as part of assigned responsibilities, serve as the future Director of the Maize Genetics Stock Center. This individual has not yet been selected. In the interim, it will be helpful in identifying and channeling inquiries relating to the Stock Center if inquiries are directed in the following way:

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