BARBADOS CHERRY AND THE IMPOR

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1 LEDIN: BARBADOS CHERRY SELECTIONS 293 A COMPARISON OF THREE CLONES OF BARBADOS CHERRY AND THE IMPOR TANCE OF IMPROVED SELECTIONS FOR COMMERCIAL PLANTINGS R. Bruce Ledin Sub-Tropical Experiment Station Homestead The Barbados or West Indian cherry*, grown as a dooryard plant in South and Cen tral Florida for many years, is prized for its unusual cherry-like fruits. In some countries it is known as Acerola and Cereza. In recent years, this plant has received considerable at tention after Asenjo and Guzman in Puerto Rico (4) and Mustard in Florida (12) dis covered and confirmed the extremely high vitamin C content of the fruit. A number of publications in both Puerto Rico and Florida have described the plant, its culture, propa gation, uses and vitamin C content (1, 2, 3, 5, 6, 7, 9, 10, 11, 13, 14, 16, 17). Barbados cherry grown from seed shows considerable variation in growth habit, flow ering and fruiting, fruit size, quality and flav or, vitamin C content and yields. Therefore, in order to establish desirable clones, it is necessary to select seedlings which have su perior qualities. Plants selected for vegetative propagation year. should: 1. Produce heavy yields that increase every 2. Yield large fruit with large amounts of juice. 3. Bear fruit with relatively thick skin and firm flesh to aid in reducing bruising and me chanical injury during harvests. 4. Bear fruit with a desirable flavor, either tart or sweet, depending on personal prefer ence and use. For eating out-or-hand, a sweet fruit is usually most popular. For processing, tart varieties may be preferred. For general purposes, the semi-sweet seems satisfactory. Taxonomic studies are being made to determine whether the correct scientific name is Malpighia punicifolia L. or Malpighia glabra L. Florida Agricultural Experiment Station Journal Series No Grow erect and open rather than spreading and thick. 6. Be easily propagated from cuttings. Plants that bear fruit with high vitamin C content are most desirable. But because most seedlings will produce fruit with more vitamin C than other fruits, this may not be so im portant. Any fruit that yields more than 1,000 mg. of ascorbic acid per 100 grams of juice would be satisfactory. However, if the vitamin C were to be extracted or used to enrich other fruit juices, those clones bearing fruit with most vitamin C would be preferred. Sweetness in the Barbados cherry is not correlated with ascorbic acid content. The acidity may be re lated to the malic acid because the sweet selection lacks malic acid but it is present in the tart varieties (15, 18). Considerable work on variety selection has been done in Puerto Rico where a number of clones have been tested for several years. One variety, B17, described in 1954 (1), has been most outstanding. However, according to Arostegui and Pennock (2), this clone, as well as others, apparently has not been suf ficiently tested in the field to recommend as a replacement for seedlings in commercial plantings.. The Sub-Tropical Experiment Station has been interested in the Barbados cherry for many years as a fruit plant for Florida. During the 1930's, a number of plants were grown in the tropical fruit collection here and many seedlings were distributed for trial in Florida. In view of the recent commercial interest in this fruit, emphasis has been placed on selec tions of clones which show the characteristics described above. Three desirable clones were selected for field testing. One produced a semi-sweet fruit. The others bear tart fruits. Ten plants of each of these selections were planted in the field in Records on growth and yields have been kept since 1952.

2 294 FLORIDA STATE HORTICULTURAL SOCIETY, 1956 One of the tart varieties was designated as SES The original plant was located on the Page homestead in the Redlands area of Dade County. Cuttings were made in 1936 and one plant was set in the field. It grew well, produced large, pale red fruits which were juicy, tart and good-flavored. In 1947, SES 1000 was selected as a tart variety to be field-tested. Ten rooted cuttings were set out in The skin of the fruit is extremely thin much thinner than fruit from other clones. Bruising, therefore, is a problem. The flowers are unusual; that is, they are almost pure white. The plants, somewhat dwarf, have thick heads, with spreading branches that tend to break when the fruit set is heavy. Yields have been consistently lower than other selec tions. The ascorbic acid content of a sample of juice was 1,050 mg. per 100 grams of juice. Because of the low yields, low ascorbic acid content, thin skin, and undesirable growth habits, this selection is not recom mended for field planting, The other tart variety grew at the home of Mr. S. Younghans of Miami. Cuttings were made in 1947 and 10 plants were set in the test block in The plants are bushy, spreading, and have numerous thick branches that form a dense head. The leaves are uni formly small and the flowers, rosy red. The dark-red fruit tastes tart but is pleasant. The ascorbic acid content of a sample of juice was 1,900 mg. per 100 grams of puice. The plants, bear heavily from May to October and No vember, which is much later than the other selections. Yields have been satisfactory, but not as high as the sweet variety. The main fault of this selection is its marked tendency to produce small fruit, even when treated the same as the other clones. Quite often, fruit of an entire harvest will average one-half inch or less in diameter. Because of this trait and the poor habit of growth, this clone is not desir able. The third selection was designated as the "sweet" variety. In 1940, 200 seeds from a plant at the Sub-Tropical Experiment Station were planted. Twenty-five germinated and 9 plants were set in the field in The rest were distributed, some to the Dade County Nursery. One of the plants grown at this Nursery produced much sweeter fruit than any grown in Florida so far. Three cuttings ob tained from this plant were set in the field at the Sub-Tropical Experiment Station in The next year these plants were killed by a flood but not before 16 cuttings were obtained. In 1949, 10 of these rooted cuttings were planted in the test block. The sweet variety is best in vigor, habit of growth, cold tolerance, ease of propagation, yields, size of fruit, high juice content, flavor, skin thickness, and resistance to stink bugs. It also has a satisfactory ascorbic acid content. "Florida Sweet Barbados cherry" is proposed as a name for this selection. Description The Florida Sweet Barbados cherry grows upright and produces branches which grad ually spread, forming an erect and open bush (Fig. 1). At six years of age plants are about eight feet in height. This variety is more vigorous and faster growing than the other clones on test. The branches are thick and woody and have conspicuous, raised, white lenticels. Fig. 1. Florida Sweet Barbados cherry 6 years in the field. Notice the characteristic upright and open type of growth. The leaves are opposite and simple, and when young are clothed with white, silky, appressed, two-branched hairs. Typical of the species, these hairs are somewhat irritating and rub off easily on contact. The herbaceous

3 LEDIN: BARBADOS CHERRY SELECTIONS 295 stems also have these hairs. As the leaves and stems mature, they become glabrous. Branch ing is characteristically opposite or 4-ranked, especially noticeable on the new growth. The leaves and manner of branching are of two types, which seems to be characteristic of most large-fruited forms of Barbados cherry (Fig. 2). These are: 1) New terminal growth Inflorescences are also of two types (Fig 2). Those produced in the axils of the lower leaves of the terminal growth are definitely stalked and with 2 to 4 flowers. The inflores cences on the short spinescent, lateral shoots are invariably sessile with 1 to 6 flowers. The flowers, up to an inch across, are a bright rosy-pink in color, but fade with age. The fruit (Fig. 2) is depressed-globular, a little wider than long, shallowly 3-lobed, and a bright-to dark-red in color. The diameter averages one inch but fruit often grows to lm inches, and the weight is one-half ounce or slightly more. The fruit has a thicker skin than some of the other selections. It also ap pears to be less susceptible to stink bug at tacks. The ascorbic acid content varied from 1,500 to 2,000 mg. per 100 grams of juice, averaging 1,700 (18). The fruits are so juicy that with normal pressure two-thirds of their weight can be extracted as liquid. The juice is an attractive red color with a semi-sweet, but agreeable taste. This selection is called "sweet" because, when eaten out-of-hand, it lacks the characteristic tartness of most Bar bados cherries. P I M.! I M M H! J S Fig. 2. Florida Sweet Barbados cherry. Notice the large fruit and the contrast between the large leaves on the terminal branch (left) and the small leaves on the short lateral shoot (right). Both are borne on the same plant. 6 inches to 2 feet or more in length with long internodes. The leaves on this growth are quite large, ovate to ovate-elliptical and with a short, acute, mucronate apex. 2) Short shoots or lateral spurs with very short inter nodes and usually ending in a blunt spur. These shoots develop from the axils of the lower leaves on the new terminal growth, as well as on mature wood. The leaves on the short shoots are mostly elliptical or obovateelliptical and usually have an obtuse or notched, mucronate apex. Later in the season, or in the following years, terminals may rise from the lower nodes and terminal buds of these short shoots. With proper cultivation, fertilizing, and watering during dry periods (7), the fruit develops to maximum size. Flowering begins in April or May, depending on the weather conditions. Fruits will mature within a few weeks. Heavy crops continue to be produced, off and on, throughout May, June and July, but crops in August to October or November are generally lighter. The Florida Sweet has out-produced the other selection in every year that yield records have been kept. Comparison of the yields of the Sweet with the other clones from 1952 through 1955 are given in Table 1. Estimates were made for the yields per acre of the Florida Sweet Barbados cherry planted 12 by 12 feet apart, or 300 plants per acre. These figures are given in Table 2. In 1955, an average of 69 pounds of fruit per plant were produced. This would amount to over 20,000 pounds of fruit per acre. The harvest dates and the number of pounds of fruit harvested from ten plants in 1955 are given in Table 3.

4 296 FLORIDA STATE HORTICULTURAL SOCIETY, 1956 Table 1. Average yields per plant of the three clones of Barbados cherry. Year Sweet SES 1000 Younghans U Table 2. Yields of the Florida Sweet Barbados cherry from 1952 to in Age field Year Average per plant (ibs.; Yield per acre (300 plants) i lbsv 3 k ^ ,700 3,000 6,300 20,700 39,300 Table 3. Yields of the Florida Sweet Barbados cherry from 10 plants 6 years in the field* Date Yield in pounds Date Yield in pounds 5 a 5/7 5/10 5/13 5/16 5/20 5/23 5/27 6/2 6/7 6/14 6/22 7/1 7/ /15 8/3O 9/5 9/9 9/17 9/24 9/26 10/3 10/10 / TOTAL

5 WHITMAN, ET AL: RARE FRUIT COUNCIL 297 The Florida Sweet Barbados cherry seems to be hardier than the other clones. It was not injured when the temperature fell below 33 F. for 8 hours on January 15, 1956, yet some defoliation and twig burn occurred in the other selections, especially on branches near the ground. The Florida Sweet also can be propagated more readily from cuttings. Al though slow in rooting, cuttings of the Sweet selection consistently root better than the other clones. A number of new selections are being tested in the field. These include tart selec tions originating at the Experiment Station and Puerto Rico. Also, a number of seedlings planted out in 1954 are under observation. Summary. The Barbados cherry shows con siderable variation when grown from seed. The desired characters to be looked for in selecting seedlings for clonal propagation are outlined. Of the three clones of Barbados cherry under field observation since 1949 at the Sub-Tropical Experiment Station, the semi-rsweet clone has been most outstanding and it is considered superior in many respects. It is proposed to name this selection the "Florida Sweet Barbados cherry." REFERENCES 1. Arostegui, F., C. F. Asenjo, A. I. Muniz, and L. Alemany Studies on the West Indian cherry, Malpighia punicifolia L.; Observation and data on a promising selection. Proc. Fla. State Hort. Soc. 67: (Also in Jour. Agric. Univ. Puerto Rico 39 (2) : 51-56, 1955, as "Observations and data on a promising selection of the West Indian cherry, Malpighia punicifolia L.") 2. Arostegui, F., and W. Pennock The Acerola. Univ. Puerto Rico Agr. Exp. Sta. Misc. Publ. No. 15, 10 pages. 3. Asenjo, C. F. and C. G. Moscoso Ascorbic acid content and other characteristics of the West Indian Cherry. Food Research 15 (2) : Asenjo, C. F. and A. R. F. de Guzman The high ascorbic acid content of the West Indian cherry. Science 103: Asenjo, C. F The story of the West In dian cherry (Malpighia punicifolia L.) Boletin del Colegio de Quimicos de Puerto Rico. 10: Gobin, M The Barbados or West Indian cherry in Florida. Univ. of Fla. Sub-Tropical Exp. Sta. Mimeographed report No. 14, 3 pages. 7. Ledin, R. B The West Indian or Barbados cherry. Univ. of Fla. Sub-Tropical Exp. Sta. Mimeo graphed report No. 56-1, 6 pages. Also in Citrus In dustry 36 (ll):26-27 and 36 (12) : Ledin, R. B A report on improvement of subtropical fruits at the Sub-Tropical Experiment Station, Homestead, Florida. Ceiba 4 (5): Levy, R. A Acerola, a new source of Vitamin C. La Hacienda, June 10, p Morton, K. and Julia Morton Fifty tropical fruits of Nassau. Text House, Jnc. Coral Gables, Fla. p Moscoso, C. G West Indian cherries and the production of ascorbic acid. Univ. of Puerto Rico Agr. Exp. Sta. Misc. Publ. No pages. 12. Mustard, M. J The ascorbic acid con tent of some Malpighia fruits and jellies. Science 104: Ruehle, G. D Miscellaneous tropical and subtropical Florida fruits. Univ. Fla. Agr. Ext. Ser., Bui. 156, p Revision of H. Mowery, L. R. Toy. and H. S. Wolfe's Bui. 109, Salazar, C. G Propagacion de la Acero la. Re vista del Cafe, Puerto Rico. Sept. p. 11, 13, Santini, R. Jr Identification and deter mination of polybasic organic acids present in West Indian cherries (Malpighia punicifolia L.) and in three varieties of guava (Psidium guajava). Jour. Agr. Univ. Puerto Rico 37(3): Stahl, A. L., M. Kaplow, and R. Nelson The present status and future possibilities of Bar bados cherries. Proc. Fla. State Hort. Soc. 68: Sturrock. D Tropical fruits for Southern Florida and Cuba and their uses. Arnold Arboretum Harvard University, Jamaica Plain, Mass. p Univ. of Fla. Agricultural Experiment Stations Annual Reports. 1948, p , p RARE FRUIT COUNCIL ACTIVITIES William F. Whitman, President Salvatore Mauro, Recording Secretary Seymour W. Younghans, Corresponding Secretary The activities of the Rare Fruit Council of South Florida were introduced to the Krome Memorial Section on November 2, 1955, when a paper entitled, "The Rare Fruit Council, A Tropical Fruit Study Group," was delivered at the annual meeting of the Florida State Horti cultural Society in Clearwater, Florida. On that occasion Dr. Bruce Ledin, Kendal and Julia F. Morton and William Whitman, mem bers of the Rare Fruit Council, attended the meeting as a group. Mr. Whitman delivered the paper cited, Dr. Ledin presented "Rubus Trials in South Florida" and Julia Morton, "The Emblic (Phyllanthus emhlica L.), A Rich But Neglected Source of Vitamin C." The first meeting of the Council following the Clearwater convention was held Friday evening, November 11, 1955, in the Botany Building of the University of Miami. A Flori da-grown fruit of the Indonesian "seedless"