ROOT INDUCTION IN PINE (PINUS) AND LARCH (LARIX) SPP USING AGROBACTERIUM-RHIZOGENES

Root induction on in vitro adventitious Pinus monticola Doug!. shoots from mature embryos was improved after 8 weeks co-cultivation with Agr obacterium rhizogenes Conn. strain A4 or the pRi transconjugant strain R1000 as compared to controls, and to naphthaleneacetic acid and indo leacetic acid treatments. An improvement in the number and quality of roots induced was observed on co-cultivated shoots as well as co-culti vated Pinus banksiana Lamb and Larix laricina (DuRoi) K. Koch de-roote d seedlings. Changes in substrate nutrient solution did not influence rooting as much as the presence of Agrobacterium in the rhizosphere. R ooting of cuttings from 3-year-old P. monticola trees was improved in two different seedlots with A. rhizogenes A4 strain.