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XXV. 



THE PIGMENTS OF FRUITS IN RELATION TO SOME 

 GENETIC EXPERIMENTS ON CAPSICUM ANNUUM. 



By W. R. G. ATKINS, Sc.D., F.I.C, 

 Assistant to the Professor of Botany, Trinity College, Dublin, 



AND 



G. 0. SHERRARD, A.R.C.Sc.I., 

 John Innes Horticultural Institution, Merton. 



[communicated by professor H. H. DIXON, F.R.S.] 



[Read November 24, 1914. Published January 6, 1915.] 



For some time past experiments upon the genetic relationships of varieties 

 of Capsicum liave been in progress at the Innes Horticultural Institution. 

 Through the kindness of Professor Bateson we have been provided with 

 material for the following research. The results presented here are only of 

 a preliminary nature, and in a later paper we hope to give a more complete 

 account of tlie pigments together with their absorption spectra. 



Genetics of Capsicum Fruits. 



Omitting from consideration the differences in the shapes of the fruits 

 which have at one extreme slender elongated forms and at the other almost 

 spherical ones, we shall confine ourselves to their behaviour with regard to 

 colour only. 



Tlie unripe fruits are green as a rule, but pale yellow in one family. In 

 four varieties employed they ripen to red, chocolate, orange, and yellow 

 respectively. In crossing these, red is certainly dominant to yellow,' and 

 from results obtained last year appears to be a simple dominant to chocolate 

 and orange. Chocolate and yellow, yellow and orange, and chocolate and 

 orange liave not yet been fully examined. 



The pigments are located in plastids, but beyond this no further informa- 

 tion is to hand up to the present. Ikeno (1913) thinks that yellow is the first 

 stage in the formation of the red pigment, but does not go into the chemistry 

 of the question. In tlie cross, red x chocolate, a few plants occur with 

 reddish chocolate fruits in Fo. 



1 This was first proved by Ikeno (loc. cit.). 



