Effect of Limited Oxygen Supply on Activities of Catalase, Peroxidase and Cytochrome Oxidase in Germinating Rice Seeds.

Abstract

Catalase, peroxidase and cytochrome oxidase activities were investigated quantitatively and histologically on germinating seeds and seedlings of rice plants, upland (Norin No. 24) and lowland (Norin No. 41) varieties, germinated under three germinating conditions: on the water blotted filter paper, immersed in 5 cm depth of water and in vacuum. 1) Catalase activity increased in accompanied with the elapsing of germinating time, and those were very higher under aerobic condition than in anaerobic. Catalase activitiv of the elongated coleoptile submerging in 5 cm depth of water for 4 days were remarkably lower than that of the water blotted filter paper plot, and on the contrary, that of coleoptile and root grown in the latter condition was higher in the former. 2) Peroxidase activity affecting not throughout progression of germination of seeds being even supplied limited oxygen was differed from case of catalase. That is, any germinating conditions for seeds were not promoted its activity. However, on the histological investigations for this enzymatic activity in colouring by means of tetraguajacol, it was high in dermatogen, plerome and hypocotyl tissues of embryoo, in root cap and epidermis of seminal root, especially root hair, and in the tip portion of coleoptile and young leaves of seedlings. 3) Cytochrone oxidase was shown the same tendency to catalase, namely its activity was more lower in seeds germinated under anaerobic conditions than other conditions, and in the coleoptile than in root of seedlings. On histological investigations by Nadi reagent, the activity of cytochrome oxidase was high in dermatogen, periblem and plerome of radicle, and in hypocotyl, cotyledon and plumule, moreover it was high in the root tip portion of seedling. However, activities of enzyme being obtained from coleoptile and young leaves were all over. 4) From above mentioned results, it is considered that catalase and cytochrome oxidase have some connection with elongation after germination of rice seeds, and especially in the latter.