Further investigations on the inheritance of a variegated strain in rice.

Abstract

The authors reported previously that the inheritance of a variegated strain in rice plays due to mutable plastids. Further investigations of some lines were continued after generations, with the results mentioned below. ( 1 ) The reciprocal crosses were made among common green rice, variegated strain in question, ajo:d green, and yellow lines from the var.iegated one. Thus F1 and F2 genefations were investigated, and all of those behaved as maternal inheritance (Tab. 1). Then( 2 ) three special variegated lines from the original variegated strain were tested (Tab. 2) and they were idehtifiod on the basis of the occurrence of albinotic and mosaic seedlings as well as the degree of variegation and developmental feature of it. M )reover ( 3 ) a mutated line showing yellowseedlings was obtained (Tab. 3) and this line denoted somewhat lower growth than the usual one (Tab. 4). Gradually the yellow seedlings became green from near the vein of leaf on 5 - 6, days after germination. Thus after 8-9 days they beca-me almost usual green leaves. The feature of yellow seedlings was indistinct in some year. and it seemed to be clear when sowed in a season of low temperature. Therefore ( 4 ) a preliminary test for temperature was done at the stage of gen:nination. In late July, matterials treated for 2 days with water were maintained 3 - 5 days at temperatures 5, lO, 15, 18, 21, 25 and 40 'C respectively. Then they were removed to the usual room (ca. 30'C) and the colour of seedling leaves was obsereved. From this result (Tab. 5) the 2nd leaf of seedlings maintained at 15'C showed yellow clearly, but no reaction around 30'C (room temperature). Moreover, at a temperature as low as 5 'C the change of colour was indistinct, perhaps depending upon almost stoppage of growth. At a high temperature as 40'C, the leaf also became somewhat yellow due to inhibition of chlorophyil formation.