Yellow seedling and its response to some environmental conditionsin rice

Abstract

In a variegated rice variety, "Fukuijima", a mutant strain was found which assumed yellw colour on the stem and leaf at the seedling stage. The expression of this character was strongly affected by varying temperatures. Some other effects on the expression of the mutant character were as follows : 1. The sparser it was sown, the clearer the colour appeared on the seedling. 2. Unscreened direct sun-light brought about more marked development of the colour than that screened with a covering of bleached white cotton cloth. 3. Generally speaking, the seedlings in the fertilized plots showed a clearer expression cf yellow character. No ccnsiderable difference wels usuallly observable between completely and incompletely fertilized plots, but sometimes a higher grade of yellow character was observed in the former. 4. The seedlings treated with a gibberellin solution (10 ppm) became yellower in colour than those untreated. 5. Measurements of plant height were conducted in the plots with various densities, with difierent amounts of fertilizer, and with or without gibberellin treatment, respectively, with the results that plants excelling in height were distinctively yellow whereas shorter ones were dark green in colour 6. In view of the above results some considerations are given on the appearance of the yellow character cr leaf pigment in relation to intensity of light, amount of fertilizer, etc., as well as partly on the plant growth.