Physiological and Ecological Studies on Barnyard Grass (Echinochloa crus-galli Beauv. var. oryzicola Ohwi) : VI. On the elongation of plumule through soils after germination.

[摘要] The present report deals with the elongation of plumule through soils after germination. 1) The maximum elongation length of plumule was about 10 cm in a dark germinator. Relation between temperature and the elongation of plumule in a dark germinator was similar at the germination. However, minimum temperature in the elongation of plumule was slightly lower than at germination. 2) Elongation of plumule was inhibited under the low oxygen tension (below 5 per cent), especially in nitrogen gas, plumule stopped to elongate at 0.5 to 3 cm, and seedling died prematurely. 3) Elongation length of plumule in the submerged soils differed from Eh value of the soil. The maximum elongation length of plumule in the submerged soils with below 300 mV of Eh6 were about 2 cm long. 4) In the storaged seeds in the submerged soil for 8 years, the plumule of about a quater of germinated seeds elongated abnormally. Moreover, even normal plumules were below about 40 per cent in length compared with storaged seeds in the submerged soil for a year. 5) As the results of these findings, it was clarified that effects of environmental factors on the elongation of plumule through soils after the germination are the same in the case of germination. Accordingly, emergence rate of germinated seeds was the highest in the optimum soil condition for germination.

[学科分类] 农业科学（综合）