RA 00110.pdf - OAR@ICRISAT

genome male-sterile lines, and A A ' genome malefertile
plants are produced from certain crosses
(Hanna 1983).
The latter group of A A ' plants are of interest (Fig.
1). The production of diploid plants without B
genome chromosomes with at least part of the A'
genome from napiergrass has opened access to the
vast storehouse of germplasm that has accumulated
on the A' genome since the beginning of the species.
The A A ' plants apparently result from an occasional
Pearl m i l l e t
(2n = 14, AA genome)
X
N a p i e r g r a s s
(2n = 4x = 28, A'A'BB genomes)
F 1 t r i p l o i d
(2n = 3x = 2 1 , AA'B)
Male and female s t e r i l e
C o l c h i c i n e
X
Pearl m i l l e t 1
(2n = 14, AA)
H e x a p l o i d
(2n = 6x = 42, AAA'A'BB)
Male and female f e r t i l e
X
Pearl m i l l e t 2
(2n = 4x = 28, AAAA)
X
C y t o p l a s m i c 3
male s t e r i l e
p e a r l m i l l e t
(2n = 14, AA)
BC 1 X Pearl m i l l e t
(2n = 21 t o 35) (2n = 14, AA)
A and B genomes
BC 2 X Pearl m i l l e t
(2n = 18 t o 33) (2n = 14, AA)
A and B genomes
BC 1
(2n = 5x = 35, AAAA'B)
Range 2n = 28 to 46
Male and female s t e r i l e
BC 1
1. 2n = 4x = 28, AAA'B
Male and female
s t e r i l e
2. 2n = 14, AA
Male s t e r i l e , female
f e r t i l e
3. 2n = 14, AA'
Male s t e r i l e , female
f e r t i l e
4. 2n = 14, AA'
Male and female
f e r t i l e
BC 3
1. 2n = 14, AA
Male and female f e r t i l e
2. 2n = 15, A and B genomes
High s t e r i l i t y
3. 2n = 16 or 17, A genomes
High s t e r i l i t y
1. Guildenhuys and B r i x (1969)
2. Hanna ( 1 9 8 4 ) , Personal communication
3. Hanna (1983)
Figure 1. Pearl millet x napiergrass hybrids and backcross progenies with pearl millet.
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