6. The following list of mutants is submitted as a sample of the types of mutant observed following treatment of pollen with ultra-violet radiation. The list includes the seed and seedling character mutations observed in experiments recently reported (Proc. Nat. Acad. Sci. 22:572-578) in which unfiltered radiation from a commercial quartz mercury vapor arc was used. Similar mutants have been observed in later experiments.

Many of the mutants listed are of little value for general genetic purposes, because of lethality or low viability, or in a few cases, because of overlapping the normal type. In (2), (15), and (33) the parent F1 plant had defective pollen, but the mutant appeared to be unrelated to the factor causing the pollen defect. In all other cases the parent F1 plant had normal pollen so far as could be determined by pollen examination. It is possible that among the mutant seed characters reported there may be included instances of small seed due to heterozygous deficiencies not manifested by defective pollen development. Tests against this possibility have not yet been completed.

Mutant Description
(seedling character)		 Notes
(1) red leaf dark to faint red coloration in seedling leaves not distinct on mature plants
(2) virescent yellow-green-a some seedlings virescent yellow green, others near white possibly two separate mutants; may be associated with small seed
(3) glossy-a glossy seedling with possibly some normal overlap occurred with a small seed, unlinked
(4) yellow green-a clear yellow green, later develops necrotic areas and dies  
(5) virescent yellow green-b nearly pure yellow at emergence; turns green probably a usable mutant
(6) rolled early seedling leaves tightly rolled and adherent many die but a few survive to produce normal mature plants
(7) dwarf dwarf seedling and plant not induced; possibly a recurrence of dwarf 3; closely linked with wx
(8) corrugated leaves narrow with well marked corrugation occurred with aleurone spot; original material showed complete association with aleurone spot
(9) virescent yellow green-c nearly pure yellow on emergence, gradually turns a greenish yellow probably a usable mutant
(10) speckled seedling leaves prominently speckled and semi dwarf  
(11) yellow green-b seedlings distinct yellow green; do not green up in seedling stage may be viable
(12) glossy-b clear glossy indication of linkage with pr; tentatively designated as gl8
(13) virescent yellow seedlings appear luteus with slight greening lethal
(14) yellow green-c segregates for yellow green and white seedlings occurred with a germless, unlinked
(15) white tip seedling leaves have a distinct white tip; present also on some mature plants occurred with an unassociated pollen segregation
(16) germless-a    
(17) small-a 1/8-1/4 normal size deficiency of small seeds
(18) small-b 1/10-3/4 normal size; very irregular shape occurred with a virescent yellow green, unlinked
(19) aborted very small and poorly developed all aborted seeds are germless, but some normal size germless seeds present
(20) small-c clear separation, approximately 25% recessive type many small seeds are germless
(21) small-d seeds normal in height and width, reduced in thickness occurred with a glossy seedling, unlinked
(22) miniature-a seeds reduced in size and characteristically scarred  
(23) miniature-b variable in size with probable normal overlap  
(24) miniature-c seed size reduced but with probable normal overlap occurred in check, not induced
(25) aleurone spot aleurone layer absent in scattered areas over the seed occurred with seedling character corrugated
(26) small-e seeds normal width and 1/4-3/4 normal height and thickness only slight deficiency of small
(27) germless-b seeds normal in size marked deficiency of germless seeds
(28) miniature-d seeds about 1/2 normal size, some normal overlap all miniature seeds are germless
(29) small-f seed reduced in size small seeds are germless
(30) gnarled seeds small and variously mis-shapen  
31) shriveled seeds poorly developed and shriveled shriveled are also germless
(32) miniature-e seeds 1/2-3/4 normal size apparently clear separation small seeds not germless
(33) miniature-f seeds reduced in size not germless
(34) germless-b seeds nearly normal size  
(35) scar scarred seeds range from 1/8 to normal size  
(36) miniature-g seeds 1/8-1/2 normal thickness and 3/4 height and width  
(37) germless-c many seed also scar occurred with virescent yellow and white seedlings, unlinked

Further information regarding these mutants will be included in a research bulletin of the Missouri Agricultural Experiment Station.

C. F. Sprague and L. J. Stadler.