Effects of Rootstock and Length of Interstem on Growth of One-Year-Old Apple Plants in Sand Culture1
in Journal of the American Society for Horticultural ScienceAbstract
Comparisons were made of MM.111, MM.106 and EM.IX as rootstocks and ‘Red Delicious’ (RD), MM.106 and EM.IX as 1-, 3-, 5- and 7-inch interstems. The dwarfing effects of the rootstocks were greater than those of the interstems. Interstems reduced the growth of most plant parts in direct proportion to the degree of dwarfing of the interstem and there were few significant differences among plants with different interstem lengths. However, plants with interstems of 1 and 3 inches had higher percentage increases in root weight than those with 5 and 7 inch interstems. Plants with EM.IX interstems showed similar patterns of total plant, leaf and new growth weights. Weight increases of RD interstems were lower than those of MM. 106 and EM.IX interstems. The EM.IX rootstock weights were 101 percent of the weights of the plant tops, whereas rootstock weights were approximately 50 percent of the weights of plant tops for all other treatments.
Contributor Notes
Received for publication April 23, 1970. The investigation reported in this paper (No. 70-10-41) is part of a project of the Kentucky Agricultural Experiment Station and is published with approval of the Director.
Associate Professor of Horticulture.
The authors wish to thank Dr. R. F. Carlson, Horticultural Department, Michigan State University, East Lansing, for advice given when this experiment was started. Thanks are also due to Dr. J. C. Williams, Agronomy Department, University of Kentucky, for statistical and computing advice and to Mrs. E. Duff for technical assistance.
Private communication.
