Effects of sunflower (Helianthus annuus L.) pollen storage conditions on pollen viability and progeny Mdh1 allelic frequency

Storing pollen for long periods could have advantages in germplasm maintenance because it would allow preservation of a large sample of genetic diversity in a very small area. This study tested different storage conditions on viability and gene frequency changes of progeny of crosses from stored pollen. Pollen was collected into glass vials from 1986 field grown plants. Samples were then dried for four hours and placed into storage in a refrigerator, a refrigerator freezer, and into liquid nitrogen for 220 to 360 days. Heads of C!·!SHA 89 grown in the greenhouse during the winter of 1986 - 1987 and in the field during 1987 were pollinated with pollen from the various storage media. Seed set varied from 140 to O percent of seed set from crosses with fresh pollen. Fresh pollen (check) produced an average 26 percent seed set. Pollen stored in liquid nitrogen produced seed set greater than the check through about 360 days. Refrigerator-stored pollen lost viability over the period from 220 to 360 days in storage (110 to 17 percent of check), as did freezer stored pollen (47 to 0 percent of check). Malate dehydrogenase isozyme locus Mdhl was evaluated for changes in allele frequency of progeny from liquid nitrogen and refrigerator stored pollen. No significant allele frequency changes were observed