Observations of Shoots and Roots from Interspecific Grafted Rosaceous Shrubs

Abstract

Plants with various shoot and root combinations of Cowania mexicana var. stansburiana (Torr.) Jeps. (cliffrose), Purshia glandulosa Curran (desert bitterbrush), and Purchia tridentata (Pursh) DC. (antelope bitterbrush) were relatively easy to produce by grafting. The foreign roots or shoots in multi-shoot or multi-root systems were not as vigorous as the original scion or rootstock. With time the original scion or rootstock became dominant and the foreign portions usually senesced. If growth of the original scion or rootstock was restricted by pruning or removal, satisfactory growth for both shoot or root types occurred. Manipulating grafted systems where Fallugia paradoxa, (D. Don) Endl., Apache plume, (a non-nodulating genus) is combined with any of the above 3 nodulating species was much more difficult. Graft incompatibility occurred in most intergeneric Fallugia systems, but some combinations survived for several years. A large quantity of nodules was produced on 1 very sparsely rooted P. tridentata scion attached to a Fallugia rootstock. Apparently, the plant derived much of its nitrogen from Purshia nodules, and the majority of its other nutrients and water from the Fallugia roots.