Inheritance of Gelatinization Temperature in Rice*

The present study relates to qualitative genetic characterisation of one of the major indices of cooking quality namely gelatinization temperature as measured by KOH degradation. All possible cross combinations of five parents were analyzed in F₂ and F₃ seed generations alongwith parents.

The qualitative analysis of the F₂ data through χ^s testing suggested continuous variation with unimodal distribution in crosses involving medium × medium and low × low GT types while in the crosses of medium × low GT types the distribution pattern was bimodal. The phenotypic classes did not fit into any of the mendelian ratios even at tetragenic level. Occurrence of low and high GT segregants in the F₂ populations of medium × low and low x low crosses was quite interesting while in medium × medium the direction of trans-gressive segregation varied with the cross. From the present finding and other indirect evidences the inheritance of this character appeared to be as complex as that of amylose content.