Species

B. viscida

Photos

3 photos

Identity

Genus: Begonia
Name: B. viscida
Author: Rudolf Ziesenhenne, Begonian
Publication Date: 1969
Place: Oaxaca
Habitat: On a dry bank at Lapajuia, district of Miahuatlan, Oaxaca, Mexico, Mr. Thomas MacDougall on January 21, 1964
Country: Mexico
Region: America
Section: Knesebeckia
Chr 2n: 28
Plant Type: Rhizomatous
Reference: Begonian 36:83, pl. 1969; JGSL9/08;
Photo References: JBS, Begonias :70. 1980; The Begonian, Apr 1969; Begonias, Misono 1974: 173 (2985);

Plant

Description: BEGONIA VISCIDA ZIES. On a dry bank at Lapajuia, district of Miahuatlan, Oaxaca, Mexico, Mr. Thomas MacDougall on January 21, 1964 collected a most unusual Begonia which he numbered C251. He routinely brought in tubers and seeds but apparently was not aware of the significance of this Begonia which because of its unique characteristics I am naming Begonia viscida (vis-kee-da). The entire plant (except the petals, front side of the sepals and the inside of the bracts and stipules) is covered with hairs which are thin and of various lengths from one-sixteenth to one-quarter inch (one to six mm.) long and intermixed. In working with the plants and staking them, I found they produced a disagreeable sensation to the touch, the first Begonia ever to feel unpleasant to me. The plant felt sticky but left no residue on my fingers. Examining some of the leaves under the microscope, I discovered that the hairs (Figure 1) were clear or pale green but the tip of each hair has a minute ball which is colored red from within. The little red balls apparently break on touch and the substance which is exposed produces the viscous sensation, this sticky characteristic unique to this plant being the reason I name it Begonia viscida. This plant is different from the usual tuber-producing plant in which normally the lowest joint or section of the stem of' the first-year plant swells up and stores in a tuber the essential material sufficient to send up a new flowering plant the next year, the tuber being classified as perennial as it usually increases in size and lasts for years. (I planted seed of a tuberous Begonia hybrid in 1940 and the same tuber it produced was doing nicely in 1965.) B. viscida is not a plant of this type, being most unusual in that the top and the tuber both are annual. When the tuber (Figure 2) is planted, the smallest end is placed up and will send up one or more stems. This tuber remains in the soil all season until its substance is used up, shriveling during the dry months after the top of the plant is lost. As the stems produced from this tuber grow, however, each one sends down into the soil a growth which, gradually develops into a new tuber to produce a new plant the following' year. I have studied this tuber formation in a closely related Begonia palmaris A. DC. which has the same habit. As an experiment, I planted the tuber with the top one inch above the soil. A stem was produced, and when it was about six inches tall, a peculiar growth developed from the' stem bud at a joint nearest the soil. This growth entered the soil and grew right on down to the bottom of the pot, and at the end of the growing season I found the new tuber. I have also learned that if the tuber is planted deeply and the new stem has to grow some distance to reach the surface, each stem bud below the soil can develop into a tuber, the tubers produced altemately on opposite sides of the stem just like a branch would be produced above ground. When the stem is fully grown and the tuber is. produced, one can see that' the tuber is affixed to the stem at a node, the side shoot of the previous year actually producing a main plant this year. The next node above and below this point have buds on the opposite side of the stem which may also produce tubers. The tuber produces fine, thin roots all over its surface. The use of a tall flower pot instead of. a shallow fern pan is almost mandatory as the swelling of this tuber resting against the pot bottom will" lift the entire soil ball an inch or more off the bottom of the pot. In a shallow pot, this growth sometimes goes out. the hole in the bottom of the pot, the tuber swelling on both sides of the hole and being necessarily damaged when one tries to harvest it. The tubers are of various shapes influenced by hard materials such as sticks and stones in the soil but are mostly as pictured in the illustration (Fig. 2). Because each stem which arises from the planted tuber produces its own new tuber, the plant increases its number naturally. I have even observed the formation of small tubers on the base of the old tubers from the base of the few larger roots. Besides B. palmaris A. DC., B. ignea Warz. has similar tuber production, both Begonias being closely related to B. viscida. I am increasingly convinced that it is necessary to study growing Begonias in order to really understand them and properly describe the plants. The dried plant resembles little of the living plant but in the past, has been the only means of obtaining the plants. The study of the plants technically should now be done with living material to present the species in a clear and correct manner. Begonias are so similar that only through modern methods can the whole Begonia confusion be cleared up. It was by growing B. viscida that it was possible to discover that this plant is dioecious. This means that a plant is either a producer of male flowers or female flowers but not both. We have been taught that all Begonias are monecious, producing both male and female flowers on the same plant, but the male flowers are usually gone before the female flowers mature, thus preventing the female flowers from being self-pollinated. I have grown dioecious Begonias for many years. Begonia palmaris A. DC. is a dioecious plant which Mr. Mac- Dougal collected in Mexico and as I mentioned is closely related to B. viscida. I have grown another dioecious tuberous Begonia which is not closely related to B. viscida, a plant collected in Argentina and sent to the University of California at Berkeley where I obtained it with the designated number 1456 U. C. I learned through growing it that the plant is dioecious and that the flower of the male plant has four tepals while the female plant produces flowers with six tepals and a four-celled seed pod, occasionally producing a pod with three cells. This dioecious plant, which produces a tuber similar to the Andean Begonias and is perennial, was named B. micranthera Grisebach var. foliosa by Drs. Smith & Schubert. Another plant, which I have grown for over thirty years, was identified as B. micranthera Griesbach var. fimbriata Smith & Schubert but in my opinion, is B. cinnabarina Hooker. It is monecious, producing a tuber similar to the tuberous hybrids of the gardens. To the best of my knowledge the original B. micranthera Griesbach and its other varieties are monecious. Other possible cases of dioeciousness in Begonia are B. extranae Smith & Schubert, and B. nemoralis Smith & Sohubert, listed in. the description as "perhaps dioecious." A characteristic of B. viscida which needs further investigation is a growth (Figure 3) on the stem of the female plant just above and to one side of the leaf stem and opposite the flower stem which produces a stipule or bract at its base with two green stipules on the tip. The largest growth I have seen is about an inch long. Study of this immature growth has given me no clue as to what it will be when mature but I will try during the year to develop these growths to maturity. The new Begonia is described below: Begonia (Section Begoniastrum (A.DC.) Irmscher) viscida Ziesenhenne, new species. Herbaceous annual; stem base an annual tuber (Figure 2); stem annual, erect, round, fleshy, 36 inches long, one-quarter inch in diameter, not branched, distance between stem joints about two inches, thickly covered with long, slender hairs up to one-quarter .inch long, each capped with a small round, red gland; stipule (Figure 4) remaining, papery, egg-shaped, blunt tip, margin even, ciliated with glandular hairs, outside thickly hairy with thin, long hairs with a red gland on the tip, to three-eighths inch long: petioles round, to three inches long, dull, light green, covered with long to one-quarter of an inch thin hairs topped with a red glandular ball: leaf blade (Figure 5) thin, papery, light green with a brownish cast in the center of the leaf and along the nerves, entire surface uniformly covered with glandular hairs spaced about one-sixteenth inch apart up to one-sixteenth inch long, the base of these hairs clear and impressing one that the leaf is covered with minute, silver spots, dull; below pale, reddish in the leaf center and along the nerves, becoming light green between the nerves, entire surface uniformly covered with glandular hairs. spaced about one – sixteenth inch apart, up to one-sixteenth inch long; unsymmetrical egg-shaped, coming quickly to a point which tapers out gradually to a thin point and ending in a hair, margin with teeth and smaller teeth each tipped with a hair up to one-sixteenth inch long and capped with a red ball-like gland, five and three-quarters inches long and three and three-quarters inches wide; palmately eight-nerved: inflorescence axillary, dioecious, male flowers seven to an inflorescence, females mostly in twos, summer - flowering; peduncle male plants one to one and a half inches long, female plants about one inch long, round, dull, light green, covered with thin almost one-eighth inch long, greenish hairs tipped with a red, ball-like gland; pedicels male one-half inch long, female one-half inch long, covered with hairs; bracts (Figure 6) egg-shaped with the tip blunt, the margin slashed variously and fringed with glandular hairs, outside covered with glandular hairs, three-sixteenths of an inch long, one quarter inch wide; male flower (Figure 7) tepals four, white, outer two egg-shaped, tip blunt, margin (Figure 8) fimbriated, three-eighths inch long, five-sixteenths inch wide; outside covered with glandular hairs, inner two narrow inverted egg-shaped, tip coming to a point abruptly, five-sixteenth~ inch long, one-eighth inch wide; stamens about 48, filaments free, much longer than the anthers, anthers (Figure 9) ball-like; female flower (Figure 10) tepals five, white, exterior two: egg-shaped, blunt, margin minutely toothed and ciliated, back covered with glandular hairs, one-half inch long, five-sixteenths inch wide; interior three, long egg-shaped, tip coming sharply to a point, three-eighths inch long, three-sixteenths inch wide; styles (Figure 11) three, shallowly two-divided, fan-shaped, stigma papillae are along the edge and make only one twist; capsule (Figure 12) about one-half inch long, three-eighths inch wide, oblong, ends blunt, green, thickly covered with glandular hairs; wings (Figures 12 & 13) three, largest uneven depressed ovate, other two narrow crescent shaped; ovary (Figure 14) three-celled, placenta axial, two-divided, carrying seed on all surfaces. Type specimen T. MacDougal' C. 251. Lapajuia, district of Miahuatlan, Oaxaca, Mexico. On dry banks. January 21, 1964. The closest relative of B. viscida that I have been able to locate is B. nemoralis Smith & Schubert which is very likely dioecious. A study of the photograph of the type specimen of B. nemoralis Smith and Schubert and the written text reveal the following differences between these two plants: Begonia nemoralis Smith and Schubert has leaves which are angular in shape, the hairs are of uniform length, the sepals of both the male and female flowers are deeply toothed, the filaments are united and the largest wing on the seed pod is low and symmetrically rounded. Begonia viscida has leaves with no angles on the margin, glandular hairs of various lengths intermixed all over the plant, sepals of both male and female flowers which are slightly serrate, filaments free, an~ the largest wing on the seed pod unsymmetrical depressed ovate.
Plant Height: Tall

Lineage

1 descendants

Parents

No parentage recorded.

Descendants

1 recorded children

As female parent

No children recorded with this plant as the female parent.

As male parent

B. ‘Fifi Florrie’

Female parent: B. ‘Lenore Olivier’

Culture

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