G.M. Darrow, The Strawberry: History, Breeding and Physiology

23
Rating Systems for
Strawberries and Sources of
Superior Qualities

THE MATERIAL OF THIS CHAPTER is in two parts. One part describes systems for rating the various qualities of strawberries, both plant and fruit. The other part lists the sources of what are presently considered to be superior qualities. In effect, a possible method of evaluation is described, which is then followed by a list of qualities which experience suggests as deserving high valuation. This does not mean that those plants which are listed as sources of a certain highly rated quality were selected for the list by the rating system which is described. The method of rating is provided as a possible means of evaluation; it is not strictly referable to the sources of superior qualities which follow it.

From ancient times fruit varieties have been compared with each other by growers, consumers, and writers. Comparisons gradually became more objective, and descriptive terms such as poor, fair, very good, and excellent, or small, medium, and large came to express more or less definite concepts. Nursery catalogues and popular descriptions commonly use such terms. But as science developed, still more accurate measures were needed. Some of the relatively accurate measurements that are often used now are: number of fruits per pound or bushel, weight of individual fruits, color names related to wave lengths of light, puncture pressure of epidermis and flesh as a measure of firmness, etc. For physical characters such measurements can often be made, but for some qualitative characters other measures are necessary.

In order to make comparisons as useful and as simple as possible, a numerical rating system has evolved with 1 indicating poorest and 10 indicating best (Morrow, 1949). Where rapid evaluations are necessary, all qualities may be so rated. Where one or more qualities, such as size or weight, are important enough to require a more or less exact figure, actual weights or sizes of samples may be taken, and such physical measurements may be integrated into the tables, or be translated into two numerical systems for use in tables.

In small-fruit research another fruitful approach in comparing varieties, and evaluating selections and seedlings, is the use of a score of 1 to 5 to indicate qualities too low to be commercially acceptable, with scores of 6 to 10 to indicate acceptable qualities. Hence, a score below 6 for any quality would make the variety or seedling unacceptable for commercial usage and those rating 6 or more for all qualities would be acceptable.

If a rating of 6 represents a measurable physical character, the numerical rating can be relatively exact over the years. If, however, a rating of 6 be given the flavor of a strawberry variety, it is based on the scorer's concept of an integration of acid to sugar ratio, tannin content and esters, taken in comparison with other varieties having acceptable flavors. In this case, as varieties with higher flavors are introduced, an acceptable rating of 6 may shift upward and a variety formerly rating 6 may have a rating of 5. There is little doubt that chemical measurements could be made of the components of flavor to establish relatively fixed standards but at present such are not available, at least for reference in the necessarily rapid evaluation of hundreds and thousands of seedlings during a short ripening season.

In the 1947 U.S. Department of Agriculture Yearbook a brief table was given to illustrate the great differences in qualities of strawberry varieties in one locality, as follows:

Variety	Size	Produc- tiveness	Firm- ness	Flavor	Color	Resist- ance to spot	SEASON Earliestt=t1 Latestt=t10
Blakemore	7	8	8	7	9	7	2
Suwannee	7	8	5	10	8	7	3
Midland	10	10	7	9	7	9	2
Fairpeake	8	9	8	9	8	7	9
Redstar	8	7	7	7	8	9	10
Tennessee Shipper	5	8	10	5	7	7	3

These ratings were based on judgments of varieties grown in Maryland eighteen years ago. Our concept of size has changed and for this character each variety in that table would now be rated at least one point lower. For productiveness, too, each might drop one point. For firmness, our present judgment is that Blakemore should rate 9, Tennessee Shipper 9, and the others as given. Flavor, color, and spot resistance would not be changed. In season, Midland has proved to be earlier than Blakemore, perhaps enough to change its rating to 1. New standards based on new varieties are now available. Armore, Jerseybelle, and Midway are usually larger; and Armore, Pocahontas, Dixieland, and Earlidawn are more productive than Midland. Dixieland is as firm as Tennessee Shipper. No new varieties superior in flavor to Suwannee are available, no new variety for Maryland is more resistant to spot than Midland: Earlidawn may be slightly earlier than Midland, but the latter still rates 1.

In the same Yearbook article important differences between the same varieties grown in different areas were emphasized. Three varieties were rated for six characters, each variety in two locations as follows:

Variety	Location	Production	Firmness	Flavor	Color	RESISTANCEttTO Spotajlfj;f;fjdScorch
Howardt17 (Premier)	Md.	9	4	6	7	9lahj;fjdff;f'f''fd'fjf9
"	Mass.	10	6	8	8	9lahj;fjdff;f'f''fd'fjf9
Missionary	Fla.	10	8	6-9	8	7lahj;fjdff;f'f''fd'fjf7
"	No. Car.	8	5	6-9	7	6lahj;fjdff;f'f''fd'fjf6
Marshall	Oreg.	9	6	9	8	7lahj;fjdff;f'f''fd'fjf9
"	Md.	1-3	3	3-5	5	3lahj;fjdff;f'f''fd'fjf7

Differences in climate in these different regions caused important differences in the varieties-berries of Howard 17 (Premier) were considerably firmer and higher flavored in Massachusetts as compared with those Howard 17 produced in Maryland, while Marshall showed even greater differences between Oregon and Maryland grown berries.

The strawberry in general has better flavor in northern parts of the United States, or at higher elevations, where the finer flavor is due to lower night temperatures and more sunshine (longer photoperiods with moderately warm days). However, the strawberry is an extremely heterozygous octoploid, and breeding in many localities has resulted in the selection of varieties with high flavor in many areas-Albritton in North Carolina, Midland from Maryland to Massachusetts, Suwannee from Mississippi to New York, and Sparkle from New Jersey to Maine. Florida Ninety is large-fruited in Florida, but small in Maryland. Weather and climate are important, but breeding for high flavor and other characters in any given section can give varieties with high ratings there. The principal varieties of strawberries may be rated, for areas to which each is adapted, on the basis of eight characteristics considered commercially important, as follows:

Variety	1962% of Com. acreage	Size	Produc- tivity	Firm- ness	Flavor	Color	Res. to spot	SEASON Res.ttot1t=tEarliest Vertic.tt10t=tLatest
Northwest	18	8	9	8	7	8	7	6lah;fjdff;f'''fd'fjf5
Blakemore	14	6	8	8	7	9	8	8lahj;fjdff;f'f''fd'f2
Robinson	8	8	9	5-6	6	8	5	9lahjj;fjdff;f'f''fd'7
Shasta	6	9	7	7	7	9	6	6lahj;fjdff;f'f''fd'f6
Headliner	5	-7	8	--	--	--	--	8lahj;fjdff;f'f''fd'--
Tenn.tBeauty	5	7	8	7	7	8	7	8lahj;fjdff;f'f''fd' 6
Dixieland	4	8+	8	10	6	9	7	1lahj;fjdff;f'f''fd' 2
Marshall	4	8	6	5	9	7	4	4lahj;fjdff;f'f''fd'f4
Sparkle	4	7	9	6	9	9+	7	5lahj;fjdff;f'f''fd'f6
Catskill	3	8	9	6	7	7+	8	10lahj;fjdff;f'f''fd5
Fla. Ninety	3	9	9	7	7	8	9	--lahj;fjdff;f'f''fd--
Lassen	3	8	10	5-6	6	9	--	7lahj;fjdff;f'f''fd'f6
Pocahontas	3	8+	9	7	8	9	6	4lahj;fjdff;f'f''fd'f3
Albritton	2	8	8	8	9	9	9	6lahj;fjdff;f'f''fd'f6
Earlidawn	2	7-8	10	7	8	8	8	1lahj;fjdff;f'f''fd'f1
Howard 17	2	6+	9	5-6	6	6+	9	9lahj;fjdff;f'f''fd'f2
Siletz	2	6	9	8	7	8	10	8 Or lessjfip[a[-8
Goldsmith	1	9	9	--	--	--	--	--ahj;fjdff;f'f''fd'--
Jerseybelle	2	9	7	6	6	10	6	3ahj;fjdff;f'f''fd'10
Surecrop	2	7	7	--	--	--	--	10ahj;fjdff;f'f''fd4
Armore	1	9	9-10	6	8+	7	6	4ahj;fjdff;f'f''fd6-7
Dabreak	1	8	8	--	--	--	--	--ahj;fjdff;f'f''fd'--
Klonmore	1	6	7	8	7	8	10	--ahj;fjdff;f'f''fd'--
Midland		7	8	7	9	7	8+	3ahj;fjdff;f'f''fd' 1
Fairfax		7	7	7	10	7	9	6ahj;fjdff;f'f''fd' 4
Klondike		6	6	6	7	7	7	?ahj;fahj;fjdff;ff'3d'
Missionary		6	6	6	7	7	7	4ahj;fjd ff;f'f''fd'2
SengatSengana (N.Y.)		8	8	6	7-8	9	--	--ahj;fjdff;f'f''fd'6

This table gives individual values for each character. An overall score is often desires and ia sometimes useful. It involves rating for other characters, or adjusting the values for the more important qualities. Earliness or lateness may sometimes have twice the importance of some other qualities. Size or flavor may be of unusual importance. Thus, for Glenn Dale, Maryland, the relative values for several qualities may be scored as follows:

Variety	Size (1-20)	Produc- tiveness (1-20)	Firm- ness (1-10)	Flavor (1-10)	Color (1-10)	Resist- ance to spot (1-10)	SEASON 20t=tEarliest 10t=tMid 20t=tLatest	Total Score
Earlidawn	15	19	7	8	8	8	20	85
Midland	15	16	7	9+	7	8+	19	81
Dixieland	15	17	10	7	9	7	16	81
Pocahontas	16	18	7	8	9	6	12	76
Armore	19	19	6	9	7	6	14	79
Vesper	19	17	7	6	8	4	20	81

The score indicates that Vesper may be of value if leaf spot can be controlled; if not, Vesper has no value at Glenn Dale. Its estimated productiveness, its size, and its lateness indicate that extra care and expense to control leaf spot may be warranted. Earlidawn may be the most profitable variety, especially on good soil where a good stand of plants can be obtained. Midland may be the third most profitable though its higher flavor may not return a higher price to compensate for lower yield. Ratings such as the above for a few qualities that are often important may have worth in showing potential values. However, the annual cycle of weather, soil fertility, insect and disease, weed or labor factors may have sufficient impact on many other genetic qualities to change the values by limiting plant stands, vigor, flower bud formation, fruit set and fruit development. For full evaluation of varieties, it would be necessary to interrelate number and time of runner production, leaf growth and flower-bud formation and development, response to temperature, to soil moisture, and to soil fertility, resistance to Verticillium, to mildew, to leaf scorch, to many kinds of nematodes and of root fungi, to fruit rots, to bud and root weevils, to spittle-bug and to other insects, as well as response to competition by various weeds and to cultural operations. For areas other than Glenn Dale, Maryland, other qualities will be rated as most important and the qualities in Maryland may be given different values.

Though the strawberry is a highly variable octoploid and most varieties may contain both desirable and undesirable characters, if a quality is represented by a single gene in a single chromosome, it may never or very rarely be expressed. But among the millions of seedlings that have been grown, some seedlings may have the desirable character in enough chromosomes for it to be apparent, and if these are used in breeding such qualities may be bred into cultivated varieties. Thus, tests in Illinois indicated that Aberdeen had resistance to the red stele root disease. Through breeding, this reststance is now in enough chromosomes in many varieties to be useful. In the same way the continuous fruiting of Nich Ohmer under the day length and cool temperatures along the coast of California has been utilized in obtaining Shasta, Lassen, Solana, Fresno, Torrey and Tioga. Recognition of such qualities and the recording of them for breeders is essential for the improvement of the strawberry. In the 1937 Yearbook of the U.S. Department of Agriculture, a listing of sources of many qualities was given and such a listing is continued here. When a certain quality, such as red stele resistance, becomes important an intensive search may indicate a surprising number of sources. Thus, resistance to some strains of the red stele fungus may be fairly common while resistance to other strains, rare in cultivated varieties, may yet be found in wild strawberries. Hence a listing of sources is to be used as a starting point, not as the sole source of a quality.

In some instances, listed varietal characters such as disease resistance may not hold true in certain regions, for strains of a disease may have developed that can affect an otherwise notably resistant variety. Such is the case of leaf spot resistance in Howard 17 and of red-stele resistance in all varieties. In like manner, Redcoat is firm enough in Canada to be the leading commercial variety, but it is not firm enough in the United States. Catskill and Sparkle are firm enough in New York and New England, but not in Maryland. Many characters must be so interpreted. In general, with an octoploid like the strawberry, if valuable qualities are noted in two varieties, then their desired combination can be obtained if enough seedlings are grown by the cross between the two varieties.

Disease Resistance-Plants
RED-STELE RESISTANCE TO ONE OR MORE RACES:
In the United States: Aberdeen, Temple, Sparkle, Stelemaster, Sunrise, Surecrop, Fairland, Redglow, Midway, Siletz, Mollala, Maine 55, Monmouth, Orland, Md-US-683, Vermilion, Columbia, Marshall, (slight). Resistant Fragaria chiloensis selections: Yaquina, Del Norte, Nelscott, Newport, and others; of F. virginiana selections: N-3953, Sheldon; of F. ovalis: Helmick.
In Great Britain: Frith, Auchincruive seedlings, Climax, Redgauntlet, Templar, Talisman, Cambridge Vigour, Oberschlesien (German), Cambridge Rival, Perle de Prague (French).
In Canada: Guardsman;
General resistance (lower level) may be in Little Scarlet and Marshall.
MILDEW RESISTANCE:
Columbia, Catskill, Dunlap (reported susceptible in Canada), Empire, Jerseybelle, Sunrise, Klondike, Konvoy, Solana, Puget Beauty, Siletz, Sparkle, Surecrop, Tennessee Shipper, Aroma, Marshall, Orland, Florida Ninety, Albritton; in F. chiloensis,ovalls, and virginiana species.
Europe: Merton Princess, Freya, Indra, Senga Sengana, Ettersburg 80 (Huxley), Cambridge Favourite, Gorella, Lassen, Valentine.
LEAF SPOT RESISTANCE:
Aroma, Howard 17, Fairfax, Midland, Blakemore, Surecrop, Redstar, Klonmore, Dorsett, Rockhill, Temple, Albritton, Headliner, Dabreak, British Sovereign, Dresden, Tennessee Beauty, Cyclone, Empire, Earlibelle.
Sweden: Lassen, Valentine.
LEAF SCORCH RESISTANCE:
Howard 17, Midland, Surecrop, Albritton, Dorsett, Blakemore, Fairfax, Rockhill, Suwannee, Redstar, Fairpeake, Aroma, Empire, Catskill, British Sovereign, Dixieland, Dabreak, Fletcher, Geneva, Trumpeter, Sunrise, Earlibelle, Valentine.
DENDROPHOMA RESISTANCE:
Earlidawn, Howard 17.
VERICILLIUM RESISTANCE:
Vermilion, Catskill, Cavalier, Siletz, Surecrop, Sunrise, Sierra, Wiltguard, Robinson, Howard 17, Aberdeen, Marshall, Grenadier, Gem, Blakemore, (Aberdeen, Howard 17, and Temple have been reported both resistant and susceptible); in selections of F. chiloensis from North and South America.
Europe: Senga Sengana, Deutsch Evern (somewhat), Juspa, Talisman, Red gauntlet.
SALINE (ALKALINE) TOLERANCE:
Solana.
VIRUS TOLERANCE:
Northwest, Howard 17, Fairland, Blakemore, Tennessee Beauty, Siletz, Klondike, Missionary, Robinson, Columbia, Shasta, Lassen, Temple, Puget Beauty, Tioga, Mollala, F. chiloensis selections.
Europe: Madame Lafabre
FREEDOM FROM FASCIATION:
Blakemore, Missionary, Klondike, and all other southern varieties.
FREEDOM FROM VARIEGATION:
Marshall, Klondike, Lassen, Suwannee.
RESISTANCE TO ROOT-KNOT NEMATODE:
F. ovalis (platypetala, Canada #5157), Fresno, Torrey.
RESISTANCE To BLACK ROOT:
Siletz.

RESISTANCE TO VERY LOW TEMPERATURES:
F. ovalis, F. virginiana selections (No. Dak.) Cheyenne 1, 2, 3, Sioux, Radiance, Arapahoe, Ogallala, Sparta; Alaska selections; Dunlap, Glenmore, Glenheart, jubilee, Parkland, Gem.Europe: Senga Sengana, Abundance, Deutsch Evern (somewhat). (See under Russia)
RESISTANCE TO FROSTS (SPECIES):
F. virginiana"Sheldon," N. Dak., selections of F. chiloensis Chile.
RESISTANCE TO FROSTS (VARIETIES):
Earlidawn, Howard 17.
RESISTANCE TO HEAT:
Missionary, Florida Ninety, Klondike, Klonmore, Headliner, Dabreak, Blakemore, Ranger, Torrey, Lassen.
RESISTANCE TO DROUGHT:
F. ovalls, F. chiloensis, Blakemore, Marshall, Surecrop. (See under Russia, pp. 296, 298)
LOW CHILLING REQUIREMENT:
Dabreak, Headliner, Benizuru Uapan), Lassen, Klondike, Florida Ninety, Missionary, Torrey, Fresno, Tioga, Klonmore, Fukuba (Japan).

Photoperiods:
SHORT DAYS:
Ambato (Ecuador), Benizuru (Japan), Dabreak, Missionary, Florida Ninety, Fukuba Uapan), Cambridge Favourite.
FEW RUNNERS:
Earlidawn, Midland.
SUMMER FRUITING, COAST OF CALIFORNIA:
Tioga, Lassen, Goldsmith, Torrey, Fresno, Solana, Shasta, Marshall.
EVERBEARING:
Gem, Rockhill, Red Rich, Arapahoe, Radiance, Ogallala, Geneva, Ozark Beauty, Twentieth Century, Streamliner, Sparta (Canada).
Europe: Sans Rivale, Revada, Revita, Saint Claude, Saint jean, Record, Profusion, selections of F. ovalis, F. virginiana and the following varieties of F. vesca semperflorens, Montrueuse Caennaise, Belle de Meaux, Gaillons (rouge et blanc), Rugen, Baron Solemacher, Reine de Valles.
Germany: Macherauchs Dauerernte, Hertsbergs Triumph, Hummi Trisca, Ada Herzberg.
FALL CROPPING:
In favorable conditions; Redgauntlet, Talisman, Abundance, Precosa.
GOOD POLLEN PRODUCERS:
Fairfax, Empire, Midway, Puget Beauty.
Europe: Cambridge Prizewinner, Deutsch Evern, Georg Soltwedel, Maprieva, Regina, Senga Gigana, Vola.

Fruit Characters:
EARLY:
Earlidawn, Midland, Cyclone, Redglow, Torrey, Wiltguard, Dabreak, Sunrise, Ogallala, Cavalier, Grenadier,Valentine; Fukuba and Benizuri (Japan); F. virginiana and F. ovalis selections.
Europe: Glasa, Senga Precosa, Macherauchs Friihermte, Deutsch Evern, Regina, Surprise des Halles, Lihama,Valentine.
LATE:
Redstar, Vesper, Mollala, Jerseybelle, Louise, F. chiloensis.
Europe: Talisman, jucunda, Ydun, Tardive de Leopold, Souvenir de Charles Machiroux, Prof. Dr. Settegast, Dir. Paul Wallbaum, Mieze Shindler, Macherauchs Spdternte.
FIRM:
Blakemore, Dixieland, Tennessee Shipper, Albritton, Fulton, Citation, Earlibelle, Earlidawn, Florida Ninety (in Florida in winter only); Fresno, Shasta and Goldsmith, Tioga (in California); Mollala.
Europe: Merveilleuse de Tihange, Gorella, Asieta, Vigerla, Senga 29, Senga Sengana.
LARGE:
Shasta, Goldsmith, Solana, Tioga, Florida Ninety (in Florida), Dabreak (in Louisiana), Jerseybelle, Robinson, Marshall, Cyclone, Albritton, Earlidawn, Armore, Vesper, Ambato, Trumpeter.
Japan: Fukuba.
Europe: Madame Moutot, Souvenir de Charles Machiroux, Sengana Gigana, Gorella, Merton Princess, Asieta, Finn.
LIGHT SCARLET:
Blakerylore, Dixieland, Empire.
HIGH GLOSS:
Jerseybelle, Vesper, Albritton, Sparkle, Earlidawn, Tioga, Redcoat, Empire.
Europe: Glasa, Senga Gigana, Vola, Senga Precosa, Redgauntlet.
SUPERIOR FOR FREEZING:
Northwest, Midland, Earlidawn, Blakemore, Pocahontas, Redcoat, Dixieland, Klondike, Fletcher.
Europe: Senga Sengana, Senga 29.
EXCELLENT FLAVOR:
Fairfax, Suwannee, Midland, Dorsett, Marshall, Fletcher, Atmore, Albritton, Solana.
Europe: Frau Mieze Schindler, Sieger, Macherauchs Marieva, Senga Precosa, Carolina Superba, Royal Sovereign, Cambridge Favourite, Talisman, Viscountesse Hericart de Thury, Regina, Cambridge Vigour, Deutsch Evern.
RESISTANCE TO FRUIT ROTS:
Possibly Solana, Cascade, Columbia, Mollala.
Europe: Possibly jucunda, juspa, and Senga Precosa, Taskent, Redgauntlet, Valentine, Xenion.
HIGH ASCORBIC ACID:
Catskill, Suwannee, Tennessee Beauty, Marshall, Sparkle, Fairpeake,
Northwest.
Europe: Widenswil 4, Georg Soltwedel, Valentine, Konigin Luise, Senga 54, Record, Ambrosia Late, Purpuratka.
EASIEST CAPPING:
Europe: Jucunda, juspa, Gorella, Senga Precosa, Abundance.
GOOD CAPPING:
Tennessee Beauty, Fresno, Torrey, Tioga.
Europe: Cambridge Favourite, Regina, Senga Sengana, Wiidensvil 4.
PROCESSING:
Midland, Pocahontas, Earlidawn, Fresno, Tioga, Torrey, Mollala, Dixieland, Marshall, Tennessee Beauty, Sparkle, Catskill, Dabreak, Blakemore.
Europe: Marzcynka (Afrika), Abundance, Senga Sengana.
CONCENTRATED HARVEST:
Redglow, Dixieland, Pocahontas, Stelemaster, Fairland, Sunrise, Earlidawn, Surecrop.