マツ類のさし木に関する研究 : (第3報) クロマツのさし木の発根に及ぼすホルモン処理の影響

Abstract

クロマツのさし木の発根に及ぼすインドール-3-酢酸処理の影響を明らかにする目的で当年生の実生苗からとつたさし穂をもちいて実験した｡ その結果の概要を示せば次のとおりである｡ (1) カルスの形成にたいするIAA処理 (25 ~ 200 ppm) の影響はほとんどみとめられなかつた｡ (2) 発根にたいするホルモン処理の影響は採穂時期によつて若干ちがつていたが, IAA (25 ~ 200 ppm) 処理をすれば根の形成は促進せられ, 発根率がたかくなり, 発根根数が増加し, 根の長さが長くなつた｡ とりわけ, 発根根数と根長とはIAA処理の結果著しく大きくなつた｡ このような根の形成作用は 25 ~ 200 ppm の範囲ではIAAの濃度が高ければ高いほど顕著に促進せられた｡ (3) 地上部の伸長はホルモン処理をしてもほとんど促進せられなかつた｡

The following are the results of those experiments, which were conducted in order to make clear what influences the indole-3-acetic acid (IAA) treatment has on the rooting of the cuttings of Pinus Thunbergii. The cuttings were taken from the seedlings about 9 ~ 10 months after sowing. 1, The cuttings, which were treated with solution containing 25 ~ 200 ppm indole-3-acetic acid for 24 hours, formed roots more flourishingly than the non treated cuttings: in treated cuttings, the percentage of rooted cuttings was larger and the number and the length of roots per rooted cutting were greater (the influence on the latter was especially striking). These influences were conditioned in some degree by the collecting time of cuttings and were more remarkable in proportion to the concentration of the IAA solution treating the cuttings. 2, There were no noticeable influences of hormone treatment on the formation of callus tissues and the elongation of shoot.