One year old M.9/seedling rootstocks were planted and mounted after ringing with binding cord above the grafting union to induce rooting on M.9. After grafting ¢¥Tsugaru¢¥ on M.9 let them grow as whiptrees. In the early spring of second year trees were headed 60 §¯ above the ground, allowed to grow from the top bud, and periodically treated with 6-benzylamino purine (BAP) 400 ppm, 600 ppm, and 800 ppm 4 times or 8 times. BAP regardless of concentration and application times induced effectively lateral branching comparing the control, however, no differences in stem diameter and tree height. The 600 ppm and 800 ppm exerted more effect on feathering than 400 ppm and 8 times of spray produced more side branches than 4 times. There was no differences in the shoot number of longer than 30 §¯ between BAP 4 and 8 times sprays, but short shoots were more formed in 8 times sprays than in 4 times. Roots on the interstem M.9 developed so well that it seems possible to plant trees after cut off the seedling part.
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