STUDIES IN INHERITANCE IN SUGAR CANE. 



By II. B. ('owyiLL. Plant Breeder, insular Expevinient Station. 



INTRODUCTION. 



Although only a few experiuieiits liavc Inn-n conduL'tcHl in the 

 breeding work with sugar eane at this Station, for tlie soh' purpose 

 of studying inheritance and related subjects, it has bei'u tlie pur- 

 pose, as the work progressed, to secure as many useful data as pos- 

 sible from the seedlings which were ])eing propagated and selected. 

 Points which are of interest are the extent to wliich characters are 

 inherited from the parent varieties wiien the latter are self-pollin- 

 ated : whether new types are produced in the natui-e of mutations : 

 and in what manner and to what degree varieties can be expected 

 to transmit their characters to seedlings when crossed. Various cane 

 varieties have been tried as seed-producers, and it has become evident 

 that, in general, when cross-pollination has not been attempted, there 

 is clearly a difference in the appearance and apparent value of seed- 

 lings produced from the different varieties, and that there is also 

 consideral)le difference in the amount of I'esemblance to the |)arent 

 varieties. In many cases this reseinblancc is i)lain, and in others 

 there is very little similarity. The reason for this may l)c that all 

 cane varieties arc probably more or less heterozygous. Ilic cases of 

 <'losei' resemblance l)eing due to more homozygous parentage. It is 

 also jiossible that accidental intercrossing sometimes takes place be- 

 tween varieties growing in the same locality, and that this affects 

 the appearance of the resulting seedlings. Resemblance to both par- 

 ents has also been observed, when cross-pollination has been affected 

 between varieties, and it is worthy of note that in some cases simil- 

 arity to the pollinating parent is very plain. 



SKEDLLNGS SHOWING UESEMBI..\X("K I'O SEEP I'ARENT.' 



A very close resemblance of seedlings to parent cane, as to visual 

 characters, has been observed everv vear since l*)l:i in seedlings pi-o- 



^ For descriptions of i-aiie varii-lics sec "A Method of IdiiUiflciitioii and Deseription of 

 Sugar Cane Varieties and its Application to Types Orown.in Porto Kioo" ; H. B. CowRill. 

 Plant Breeder, Insular Experiment Station, Porta Ujeo : .lournal of tlie Department of Agri- 

 ettUure, Vol. 1. No. 3, .luly. 1917. 



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