Schmidt, Hannelore, and Volker Schmidt Tests of allelism for ms-15, ms-26, and ms-33. (Submitted by R. Hagemann) The male sterile mutants ms-15,  ms-26, and ms-33 can   be   normalized   with   gibberellic   acid   (GA3) (TGC  26:17)  so  that  self-pollination  is  possible. Normalized plants genetically homo- zygous male sterile) were used as the male parents in the following crosses.   It has been reported that ms-15 is localized on chromosome 2 at position 62 (TGC 8:25). The mutant ms-26 has been localized on chromosome 2 without a detailed determination of its position. The results of our crosses now prove that ms-15 and ms-26 are allelic. Although  ms-33  is  on  chromosome  6  and  there  is  no  allelism  with  ms-15  and  ms-26,  in offsprings of (2) (4) (5) and (6), some plants with small and markedly reduced anthers occur. This is not the case in simple heterozygotes of each of the three mutants. Because  in  all  three  mutants  the  reduced  level  of  GA3  seems  to  be  the  cause  of  anther reduction and pollen sterility, we assume that there is some interaction between these non-allelic mutant loci. Schmidt, Volker Test of allelism for ms-38 and ms- 40. (Submitted by R. Hagemann) The mode of meiotic degeneration in the male sterile  mutants  ms-38  and ms-40  is  very  similar. Therefore   they   have   been   crossed   to   test whether they may be allelic.   The segregation in a 1:1 ratio demonstrates allelism between ms-38 and ms-40. Stamova,  L.,  and  M.  Yordanov  A  new  gene  for resistance  to  Cladosporium  fulvum  derived from L. chilense. As   reported   previously   (TGC   25,   1975)   in progenies  of  crosses  with  L.  chilense  we  found resistance    to    races    of    the    group    C    of Cladosporium fulvum. The genetic studies of this resistance showed that it is controlled by a single dominant gene. The factor for resistance originating from L. chilense was compared in tests for allelism with three  other  sources  of  resistance  to  the  same  race  (2.3.4)  -  PI 187002 (gene Cf-5)  and  two  Dutch accessions  (63280  and  64316)  of  L.  cheesmanii  received  from  Miss  I.  Boukema.  The  Dutch  sources often show after inoculation restricted sterile mycelium, while the line 4 of the cross with L. chilense indicates complete resistance. The results from the allelic tests showed that the gene from L. chilense was non-allelic to the gene  Cf-5,  as  well  as  to  the  resistant  factors  originating  from  the  Dutch  accessions  of  L. cheesmanii.

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