Studies on the Coleorhiza of Cereals. : VII. On the coleorhiza hair of rice-plant.

[摘要] A research was made on the development of coleorhiza hairs. Four varieties, a drought resistant upland rice, Sensho, a non-resistant upland rice, Shindai Okoshi, a non-resistant paddy rice Norin no. 10, and intermediate resistant paddy rice, Shuho were used. The results obtained were as follows: 1) In a moist chamber, a large number of coleorhiza hair was formed at the germination. The diameter of coleorhiza hair exceeded that of root hair in all the varieties. However, as for the length, coleorhiza hair exceeded root hair in the two varieties of upland rice. The former fell behind the latter in Shuho variety, and the two were on a same level in Norin no. 10. 2) As for the germination rate, the seed of Sensho sprouted faster on dry soil than in paddy condition. On the contrary, Norin no. 10 sprouted faster in paddy condition. On dry soil, starch was translocated to the coleorhiza and to the tip of seminal roots faster in Sensho than in Norin No. 10. Many coleorhiza hairs were noticed in dry soil condition, but did not in paddy condition. 3) The coleorhiza hairs did not develop under a little supply of air nor in a paddy water of reduced oxygen content. The lower limit of air supply necessary for the development of coleorhiza hair seemed to lie near 2.5 % of normal condition.

[学科分类] 农业科学（综合）