1957 Volume 26 Issue 4 Pages 251-260
(1) Cuttings of wild rose (Rosa multiflora) were done on various media, i.e. sand, vermiculite, heavy clay soil, and artificially conditioned mold. This mold contained 3.5% organic matter and, 37.7% clay. The rootings and the further growth after transplanting were compared among among these plots.
(2) The cuttings on sand, vermiculite and heavy soil rooted slowly and produced thick, un-branched and brittle roots. On the conditioned mold, treated with the soil conditioner (0.05% VAMA or 0.1% HPAN ), the cuttings rooted rapidly and produced fine and branched roots. Moreover, after transplanting to the field the new plants from the sand or vermiculite plots were seemed to be stop-ped their growth, while those from the condition-ed mold continued their growth successively.
(3) The advantage of rooting on the conditioned mold was mainly due to the good water-holding and also to the good availability of nutrients of this medium. While the undesirable rooting was probably due to poor available moisture in sand, but to less air-capacity in vermiculite and heavy soil. In vermiculite and heavy soil medium, the cuttings had greater percentage of rooting and more branched roots when they were received a light irrigation.
(4) The water-stable aggregates gained by the treatment with the soil conditioner were sifted into seven fractions, i.e. 6-8mm, 4-6mm 2-4mm, 1-2mm, 0.5-1mm, 0. 22-0.5mm, and smaller than 0.22mm in diameter. Then each fraction was used as a rooting medium to determine the rooting res-ponses of the cuttings to the moisture and aera-tion in each plot. For, in this case, factors such as acidity, presence of nutrients, and size and shape of the particles of the media were seemed to be eliminated.
(5) In the case of the heavy irrigation, the plot of the 0.22-1mm aggregates were most suitable for rooting, namely the highest percentage of rooting, and. the best root-system were obtained; whereas the plot of the larger or smaller aggre-gates were not better media. In the case of the light irrigation, on the plot of the 1-2mm aggre-gates a lower percentage of rooting was shown. But the cuttings on the plot of the smaller aggre-gates than 0.22mm had a higher percentage of rooting than those irrigated heavily. In the plot of the 0.22-0.5mm aggregates, rooting was scarcely-influenced by the light or heavy irrigation. The finner the aggregate, the less air-capacity was given. The medium which have about 10% or more air-capacity was seemed to be suitable for rooting of the cuttings.
(6) Conditioned mold was compared with un-treated mold as a rooting medium. The treatment with the conditioner increased markedly the air-capacity, and subsequently increased the rooting of the cuttings and also the development of their root system.
