I was searching for a comparison of Rosa laevigata, R. banksiae and R. x fortuniana as rootstocks under varying conditions. I wasn’t able to find the info I wanted, but I did find something else that is just as interesting.
Communications in Soil Science and Plant Analysis (1979)
Effect of rootstocks on greenhouse rose flower yield and leaf nutrient levels
‘Carina’ rose was grown on seven different rootstock clones. These combinations were tested for effect on flower production and mineral content of the leaves when grown in fumigated ground beds in an evaporatively cooled plastic greenhouse. Plants growing on R. odorata ISU 5710-2 produced the highest flower yields followed by R. fortuniana and R. manetti while R. multiflora ISDU 62-5 produced the lowest number of blooms. Rootstocks caused large differences in the levels of some minerals in the leaves._ R. fortuniana_ caused a Mn accumulation that was five times the quantity developed by R. odorata but this did not seem to be related to flower production. However, R. odorata was a superior accumulator of K and under conditions of relatively low supply. R. fortuniana and R. odorata were good accumulators of N and K. These factors were related to flower yield.
http://bulbnrose.x10.mx/Roses/breeding/GammonRootstocks1979.html
I promptly remembered another note regarding nutrients and flower color.
American Rose Magazine 1(9): 14-15 (May-June 1934)
Fertilizer and Color
Dr. W. H. Brundige, TN
Four years ago I had a bed of forty-eight Red Radiances. From these I selected two bushes and used a commercial fertilizer—blood, bone, and potash in a ratio of 5-8-7. I used one pint to each bush on May 1, and such roses as they produced—dark red, with petals like velvet. The two bushes were entirely different from the others and bore the most beautiful flowers I ever saw.
http://bulbnrose.x10.mx/Roses/Rose_Pictures/R/redradiance.html
It seems reasonable to suppose that a rootstock capable of providing the relevant nutrient might serve as well as fertilizer, which could explain (at least in part) the following:
American Gardening 14(9): 519 (1893)
Influence of Different Stocks on Marechal Niel Rose
JOHN DALLAS, Connecticut
Some years ago, in experimenting with different stocks in an endeavor to find the most suitable whereon to bud Marechal Niel, I was surprised at the different results attained, showing conclusively that the stock influences the color of the flowers. … The flowers of Marechal Niel were lighter in color on this stock [America] than on Cloth of Gold, which, but for one fault, is much the best stock of those under consideration. This fault is the inability of the stock to keep pace in growth with the Marechal Niel, causing a protuberance at the point of union, and finally resulting in a cankerous disease. The flowers from this stock were a very deep yellow, remarkably so when placed beside those from the Lamarque stock. … Ophier [Ophirie] is an old rose of a tan or copper color, short dumpy buds, but a fine cup shape when nearly open. … The petals of the Marechal Niel were deeply tinted with copper color half their length, the base of the flower a deep yellow, and the form of the flower was almost identical with Ophier. All the stocks under consideration had the same soil, equal light advantages, but yet produced decidedly different shades of yellow, and each retained these characteristics until they were destroyed.
http://bulbnrose.x10.mx/Roses/Rose_Pictures/M/marechalniel.html