American Rose Annual 48: 160-165 (1963)
The Rose Gene Pool
Raymond C. Fisher, Rochester, N.Y.
Dr. Dennison Morey, Pleasanton, California

COMMERCIAL rose breeders and growers agree that new germ plasm must be introduced into garden roses. Unless this is done, improvement in garden roses will gradually diminish. Moreover, areas of possible improvement usually involve quantitative effects: e.g., greater hardiness, more fragrance, less susceptible to disease — rather than qualitative, i.e., entirely different shape of flower, color, etc.

One hundred fifty years and about a dozen species roses have gone into the making of our present garden varieties. Today out of five to ten thousand seedlings, one may be selected for commerce. The reason lies mainly in the narrow range of quantitative effects still inherent in modern roses.

Now there is much wishful thinking that all that is necessary to improve the rose is to return to the old roses or the species, make a few crosses and introduce some of their ("blood") genes into our garden beauties. If that were all that was required the task would be easy. Unfortunately, this simply doesn't work. Such offspring do not possess remontance or free flowering and if they do, all semblance of hardiness is lost. In addition, due to genetic incompatibility, it is often quite difficult to mate the wild with the tame and this difficulty ordinarily diminishes but little in the immediate subsequent generations (F1, F2, F3). The time interval for three such generations can take up to twenty years of effort. Even at the end of this time the offspring may still be sterile or at best, poor parents. As a species breeding program proceeds and some of the problems are solved one often discovers that with the dilution of a hardy species for three generations with garden blood some offspring will be remontant.

 The purpose of this article is to point out that commercial hybridizing can only enter the quest for better roses at this later stage and that the only immediately feasible chance of reaching this stage is by arousing the interest of enough amateurs to produce species derivatives with essential characteristics.

In order to accomplish this it has seemed desirable to more or less formally establish a "gene pool" program by means of which critical species and varieties, not necessarily of commercial or immediate garden interest could be made available to interested amateur hybridizers. Moreover, this program would necessarily provide technical advice of all types, data, supplies, etc. An example of what can be done is illustrated by the following chart. The chart also summarizes twenty years of fundamental and potentially significant work on the part of the senior author.

It is intended to pinpoint the potential hardiness that can be expected of tomorrow's roses and how it can be attained. It is called the dilution theory and assumes a highly multifactorial quantitative effect, which may not be strictly true in all cases. However, as a workable approximation it merits careful consideration. Of course, actual hardiness must be evaluated with field tests. Similar charts can undoubtedly be prepared for other characteristics such as floriferousness, vigor, etc.

The preparation of such charts depends upon actual results and the evaluation of them. This means testing and for best results, field testing. This aspect of the gene pool program requires facilities for moderate production of promising or inherently interesting seedlings. This would require the cooperation of a commercial enterprise. While the full importance of the proposed program is certainly not generally appreciated by the trade, it is by the junior author.

In addition to reproduction of selected seedlings the pool could serve as an integrating agency. For example: a friend of the senior author with a garden of 500 bushes permitted him to cross some. The swelling seed pods took his fancy. Being in on the idea of the pool he remarked that he would be willing to pollinate with furnished pollen but not willing to germinate the seeds. This indicates that our quest or "operation improvement" can be broken down into many small parts. It is important, however, that any and every such participant should be accredited, else errors in labeling crosses and similar oversights could be costly in time, testing, future programming and money and might even discredit the pool.

Participants who elect to serve as amateur hybridizers will find that much of the hardiness research that has already been accomplished has been in the area of F1 offspring such as "hardy species A" x "hardy species B." While of ultimate value, especially in connection with "gene bridges," such work is less pressing than hybridizations to introduce remontant garden rose blood into hardy material already one or two steps along the way. A tentative list of varieties suitable for initial crossing to garden varieties might include the following:

  Harison Lemon (29): All harisonii seedling (F1)
  Harison Salmon (29): See Modern Roses V and
  Harison's Profuse 36): Shepherd's History of the Rose
  Hillcrest Pillar (30): Page 189
P. H. Wright  
  Harison's Hardy (43): All R. spinosissima altaica by
  Golden Altai (43): Harison's Yellow (F1)
  Yellow Altai (50): See Modern Roses V and Shepherd's
  Loch Lomond (46): History of the Rose, page 188
  Hazeldean (48):  

However, far more suitable starting points are available.

At this point special attention should be called to Dr. Griffith J. Buck's article "Cold Hardiness of Rose Varieties" in 1959 American Rose Annual, p 133, which contributes the useful idea of cane injury to the dilution theory chart, and also to J. H. Nicolas' A Rose Odyssey, chapter XXIV, which gives actual winter temperature (i.e., Arcticness) tolerances of many groups of roses.

Nicolas' "Arcticness and Mathematics" 1937 American Rose Annual, p. 166, and Percy H. Wright's "The Arcticness of Various Roses" 1938 American Rose Annual p. 71, also contribute temperature values to the dilution chart.

It will take some careful study to decide how much or how little of the bushes listed in Dr. Buck's article should be carried by the pool. The extremely poor germination of F1 offspring involving the first dilution of hardy species with remontant garden roses, has discouraged many who have made the attempt. Moreover, where good seed (heavier than water) have been excised and high percentages of progeny realized, progeny from embryos that would never have been born otherwise, are often a major portion of the total and must be destroyed. Nonetheless, there will invariably be individuals from even a modest number of crosses that have merit and which will prove to be valuable parents. Fisher's 'Lorelei'* has proven to be such an individual. Its value has been verified by carrying test crosses through F2 and F3 offspring and evaluating them.

Other promising F1 material would seem to be:

  Golden Wings (53): Soeur Thérèse x (R. spinosissima altaica x Ormiston Roy) See Modern Roses V and Shepherd's History of the Rose, page 184
  Frühlingsduft (49): Joanna Hill x R. spinosissima altaica
  Frühlingsgold (37): Joanna Hill x R. spinosissima hispida
  Frühlingsmorgen (40): (E. G. Hill x Cathrine Kordes) x R. spinosissima altaica
  Frühlingszauber (42): (E. G. Hill x Cathrine Kordes) x R. spinosissima altaica
  Frühlingsschnee (54): Golden Glow x R. spinosissima altaica
  Karl Forster (31): Frau Karl Druschki x R. spinosissima altaica See Modern Roses V and Shepherd's History of the Rose, page 185
  Harriet Neese (28): Ophelia x R. x harisonii (See Modern Roses V)
  Rustica (29): Mme. Edouard Herriot x Harison's Yellow
(See Modern Roses V)
  Sonnenlicht (13): Lady Mary Fitzwilliam x Harison's Yellow (See Modern Roses V and 1957 American Rose Annual, page 143)

Fisher has evolved two highly usable F2 parents from 'Lorelei.' They will be carried in the pool inventory as the most promising material for an early attainment of some increased hardiness in commercial roses.

  1952/68/4: Lorelei on Mrs. Sam McGredy (F2)
  1954/23/4: Lorelei on (Better Times on Crimson Glory) (F2)

Kordes also has evolved an F2 parent. It should be evaluated to determine whether it, too, is highly usable.

  Frühlingstag (49): McGredy's Wonder x Frühlingsgold (F2)

Proceeding to the next level, Fisher has evolved a highly usable very free flowering orange F3 parent which has withstood a most damaging 1961-62 winter where all his garden roses were killed and his work for hardiness alone survived. This F3 individual came through with green canes. It will be carried in the pool in 1965. Using this variety it should be possible for professional hybridizers to add another garden rose dilution and come up with a commercial rose of superior hardiness.

  1960/66/6: (Lorelei on Mrs. Sam McGredy) on RMS Queen Mary (F3)

There are, of course, a vast array of other potentially promising varieties available. No attempt has been made to evaluate Skinner's work here. It deserves a good study.

The work of Dr. G. Griffith Buck with R. fedtschenkoana and R. laxa would necessarily be of great concern to those involved in such a cooperative program as is envisioned here. Dr. Glenn Viehmeyer is also involved in very constructive species work as is Dr. E. B. Risley and there are many, many others, both professional and amateur, whose efforts could be immensely enhanced by a cooperative program. Especially to be noted is the pioneer work of Dr. Robert Basye with R. bracteata and R. virginiana.

It is essential that we recognize and overcome the fact that few amateurs have the facilities for testing and propagation. Multiplication, inspection, shipping, sales and contacts so essential to any program for better roses will have to be centralized.

Actually this problem has already been resolved. Since it was probably the largest single impediment to the success of the pool, if amateur response is favorable (and the American Rose Society is able to act as coordinating liaison), progress is nearly assured. It is quite imperative the American Rose Society assume a high level of interest in such a project since it must necessarily be coordinated with the old rose preservation project.

In the initial phases, a modest level of activity will be necessary. Primary emphasis of liaison between all interested persons and groups will have to dictate the eventual nature and development of the pool. However the ultimate value of the effort cannot be denied and the time to begin is now.

*Lorelei (R. C. Fisher '47.) (Joanna Hill x Harison's Yellow) Bud ovoid; fl. Large (3-4 in), semi-dbl., v. frag., peach-pink, center yellow. Fol. Leathery, dark. Vig., upright; non-recurrent bloom. (28) (Modern Roses V)