164 CORRELATION OF COLOUR CHARACTERS IN RICE 
Ill. Band C. B segregates 9: 7, C 9: 7, so if segregating indepen- 
dently the expected ratio is— 
9 B ;: 7b 
9C AC 
8IBC: ‘63'Be : 63 bC = -49 be 
Observed ie. | 16253 att > 394 : 976 (4 families of 3,016 
plants) 
Expect ay 954°3 2 742:206 9 (742221 3 577-27 
Here the expected combinations are all present, though not in the 
expected ratios. There are too many of the parental types, BC and be, and 
too few of the cross-over types. The actual ratios obtained in the four 
different families were as follows :— 
BC : Be :- bC : be 
il 92 OO Sy Path : 90 
Ds 196 : 58 : 48 alge) 
ae 834 : 266 : 296 : 714 
4, 13] oo Bs) : 54 
MomAT ee eeleZoo : 393 : 394 : 976 
The figures are somewhat irregular, but on examination some of the 
ratios obtained are found to be a fairly close approximation to expectation 
on a basis of a 7: 1 coupling of the parental gametes. On this basis the 
expected ratios are— 
I 122 Se o0;050e te mo 0:95) sie OOo3 
2. WNG25e 9 DoW 4e sos 4 cl03°39 
By 1057°69 : 266°-44 : 26644 : 519-42 
4. 120°80 : 3044 : 30°44 : 59°32 
To definitely prove the gametic constitution of the F, it would be neces- 
sary to backcross it with the recessive parent, a very laborious undertaking 
in the case of a cereal like rice, as each cross results only in the production of 
one fertilized seed, and to obtain only 100 plants would require 100 crossings, 
and that assuming all were successful and all seeds germinated and reached 
maturity. 
5. Variety Surjamukhi x Variety Pookhi. 
(A) The combination “leaf-sheath, internode and stigma ”’ sticks 
together absolutely, giving 3 coloured : 1 colourless (992 plants 
gave 2°83: 1). 
