Meiotic studies of spontaneous hybrids of Amaranthus: genome analysis

E. J. GREIZERSTEIN, L. POGGIO

PLANT BREEDING

WILEY-BLACKWELL PUBLISHING, INC

Lugar: Berlin; Año: 1995 vol. 114 p. 448 - 450

0179-9541

The meiolic behaviour of 13 spontaneous interspecific F1 hybrids of Amaranthus was studied. The hybrids between species with n=16 chro­mosomes had 16 bivalents but varied considerably in pollen stainability (0- 55%). These results suggest the existence of cryptic structural hybridity. The hybrids involving A. cruentus (n=17) and species with n=16 (A. caudatus and A. quitensis) always farmed 15II+ 1III with very low pollen stainability (5-7%) Further observations indicated that Amaranthus species are allotetraploids with basic numbers X-8 and X-9 but exhibit X= 16 and X=17 as secondary basic numbers as demonstrated by (a) the frequent presence of 8II+17I in the meiosis of the hybrid A. spinosus (n=17) x A. hybridus (n = 16); and the occur­rence of secondary associations between bivalenls in Ml Genomic formulae are proposed for each species, on the basis of the meiotic behaviour of the hybrids studied. Key    words:    Amaranhus - basic chromosome number genome  analysis – homeology – hybrids meiotic - behav­iour polyploidy -     pseudocereal