From the book
Fruits of Warm Climates
by Julia F. Morton
Mexican Husk Tomato
Physalis ixocarpa Brot. Physalis aequata Jacq. SOLANACEAE
Somewhat suggesting a miniature tomato, the Mexican, or Mayan, husk tomato, Physalis ixocarpa Brot. (syn. P. aequata
Jacq.), is also called tomate de cáscara, tomate verde, tomate
Mexicano, tomate de fresadilla, tomate de culebra, tomatillo, miltomate
and farolito.
Description The plant, which
is a semi-woody annual, may attain a height of 4 to 5 ft (1.2-1.5 m),
but is often prostrate and spreading. Its branches and leaves are
smooth, not downy. The leaves are ovate, pointed at apex, wedge-shaped
at base, sometimes wavy-margined; 2 1/2 in (6.25 cm) long, 1 1/4 in
(3.2 cm) wide. Borne singly in the leaf axils, the flowers, clasped
halfway by a 5-toothed, green calyx, are 1/2 to 3/4 in (1.25-2 cm) long
and wide; yellow with dark-brown spots in the throat. As the fruit
develops, the calyx enlarges to more or less enclose it and finally
becomes straw-colored and papery. It is so tight-fitting that it often
bursts. The berry is slightly oblate, 1 to 2 1/2 in (2.5-6.25 cm) wide.
When ripe, its thin skin may be yellow, purple, or, more rarely
reddish, or still green. The flesh is pale-yellow, crisp or soft, and
acid, subacid, sweet, or insipid, and contains many tiny seeds.
| Fig. 116: The Mexican husk tomato, (Physalis ixocarpa), page-green, yellow, purple or reddish when ripe, is a staple food in Mexico and Guatemala and commonly marketed. |
Origin and
Distribution The
Mexican husk tomato was a prominent staple in Aztec and Mayan economy.
The plant abounds in Mexico and the highlands of Guatemala and the
fruits are commonly seen in native markets. Nevertheless, this species
has not been as widely distributed abroad as the Cape gooseberry. It
was introduced into India in the 1950's and is cultivated in the
northwest desert region of Rajasthan. In Queensland, Australia, and in
South Africa it has fruited prolifically. There is some commercial
cultivation in Pietersburg, South Africa, for processing. It was
too-successfully introduced into East Africa, for, in 1967, it was
reported to be the most important weed of agricultural fields in the
highlands of Kenya.
Before 1863, it was thoroughly naturalized
and commonly growing in abundance in the far west of the United States.
Mr. Sun Jue cultivated some 20 acres (8 ha) of Mexican husk tomatoes
near Los Angeles, California, from 1930 to about 1939, supplying the
fruits to Mexican and Italian markets. In 1945, the American Fruit
Grower publicized this species under the concocted name "Jamberry", as
a new fruit introduced by scientists at Iowa State College. Dr. I.E.
Melhus, Director of the Iowa State College Guatemala Tropical Research
Center reported in 1953 that, as a result of 6 years' testing of
hundreds of selections, only a few were found suitable for the American
Midwest. They were then sending out a strain to which they had given
the name "Mayan husk tomato"; 4,000 packets of seed were distributed in
Iowa and adjoining states. Sampling data from 200 people that grew the
plant showed that over 60% were successful and liked the fruit. Later,
that strain was offered by the Earl May Seed Company of Shenandoah,
Iowa. An apparently independent introduction was made by Glecklers,
Seedsmen, of Metamora, Ohio, and first offered by them as "Jumbo husk
tomato" in 1952. Seeds obtained from these sources and from fruits
purchased in the Mexican markets were given by the writer to
experimenters in the Bahamas, Puerto Rico, Jamaica and Florida.
Plantings
were successful in the Bahamas and Puerto Rico but did not arouse
enough interest to cause further cultivation. Florida and Jamaica
trials were failures. In recent years, test plantings have been made in
Trinidad and Taiwan, and plants have fruited well in greenhouse culture
in England. The principal areas of production in Mexico are the States
of Morelos and Hidalgo. The former has about 32,000 acres (13,000 ha)
with a total production of 101,366 tons.
Varieties There
is great variation, not only in color and flavor of the numerous
strains of Mexican husk tomato. Some require long days and others short
days. Some mature early, others late. The husk may be long or short.
The flesh may be soft and spongy or firm and crisp. A large number of
selections has been made at the Campo Agricola Experimental de
Zacatepec, in the State of Morelos, Mexico. The most promising,
'Rendidora', is more erect than the common type, the fruit is large,
green, ripens 15 days earlier than others and gives 80% greater yield.
Horticulturists at the Universidad de San Simón in Bolivia have long
maintained a collection of various types received from Mexico.
The
"Mayan husk tomato" selection at Iowa is semi-prostrate, vigorous,
branching at a height of 4 to 6 in (10-15 cm); the stems are
pale-green, smooth and succulent when young. The fruit is round,
yellow, with light-yellow, firm flesh and mild-acid flavor. According
to Dr. Margaret Menzel, an authority on the genus, the so-called
Physalis macrocarpa, or "Golden Nugget Cape Gooseberry", offered by
seedsmen in Australia, is really a yellow-fruited form of the Mexican
husk tomato, P. ixocarpa.
Pollination The
Mexican husk tomato is highly self-incompatible. When the flowering
plants are bagged, no fruits are set. K.K. Pandey, while at the
University of Ohio, studied this problem. He reported that only a few
seedlings in a group produce rare fruits by natural-selfing and such
fruits usually contain no seeds or only a small number. An occasional
fruit may have 100 or more.
Climate and Soil This
species is not ultra-tropical but tropical and, like the tomato, is
grown in summer in temperate regions. The plant needs full sun. It will
grow in any soil suitable for tomatoes but not in wet situations.
Propagation The
Mexican husk tomato is usually raised from seed and it takes about 2
1/4 oz (60 g) to plant an acre; 5 1/4 oz (150 g) to plant a hectare. In
Puerto Rico, seeds saved from the first crop and kept for 6 months
without refrigeration were planted and 80% germinated.
Cuttings
should root easily. Heavy rains cause the plants to bend down to the
ground and it has been observed that tips that touch the soil take root
and the new shoots grow vigorously.
Culture Ideal spacing for cv. 'Rendidora' is 16 in (40 cm) between plants and 4 ft (1.25 m) between rows.
From
4 to 6 seeds are planted 1/2 in (1.25 cm) deep in hills 2 ft (60 cm)
apart in rows 5 ft (1.5 m) apart. When 4 to 5 in (10-12.5 cm) high, the
seedlings are thinned to 1 plant per hill. In the midwestern United
States, seedlings are raised in greenhouses and are transplanted when
about 3 weeks old as soon as all likelihood of spring frosts is past.
They will begin to bear 6 to 18 weeks later and continue for about 1
1/2 months.
In Bahamian trials, seeds were planted in mid-April.
By mid-September, the plants were fruiting heavily. They reseeded
themselves and a healthy clump of "volunteers" sprang up on the site.
In Puerto Rico, seeds planted at Mayaguez produced an abundant crop in
the winter of 1953-54. The plot was fertilized at the rate of 2 oz (56
g) per plant, side dressing, of 9-8-8 fertilizer. The plants were
staked and tied twice and grew to a height of 5 ft (1.5 m).
Season Wild
plants in Mexico flower from June to October. In the midwestern United
States, flowering takes place in mid-June and fruits start to ripen in
late July and fruiting continues until fall frosts. The plants bear
during the summer months in South Africa; in northern India, both
summer and winter.
Harvesting With
the Mexican husk tomato, falling of fruits before ripening is not
uncommon, and, according to Dr. Melhus, they may be allowed to remain
on the ground until fully colored. Collecting must be done every day.
The green-skinned variety grown commercially by Mr. Jue was harvested
as soon as it burst its husk, and the crop was then kept on hand 2 to 4
weeks for the husk to dry before the fruit was considered acceptable to
the consumer. If left too long on the plant, there is much loss of
flavor.
Yield Individual
plants may produce 64 to 200 fruits in a season. In test plantings at
Ames, Iowa, the fruit yield averaged 2 12 lbs (1.1 kg) per plant; equal
to approximately 9 tons per acre (20.2 MT/ha). In Mexico and India,
yields of 7.5 to 10 tons per acre (17-22.5 MT/ha) have been reported.
Keeping Quality The
unhusked fresh fruits can be stored in single layers in a cool, dry
atmosphere for several months. Mexican and Central American people may
pull up the entire plant with fruits attached and hang it upside-down
in a dry place until the fruits are needed.
Pests and Diseases The
Mexican husk tomato is subject to few pests and diseases. In Mexico,
the main pest is the so-called mosquita blanca (see below). The larvae
of Heliothis virescens attack the fruits. It has been found that various species of Trichogramma
parasitize the eggs, found mainly on the underside of the leaves,
though only in certain localities at certain seasons. In India, fruit
and stem borers are troublesome during the rainy season but not in the
winter. No insects attacked the plant in Puerto Rico. The two trials in
Florida were at first promising, the plants flowering and setting fruit
satisfactorily. However, as the fruits began to mature, they were
attacked within the husk by a species of cutworm and only a few mature
fruits were harvested. In Jamaica, seeds planted in late January
produced vigorous and precocious plants which flowered when only 4 in
(10 cm) high. Fruit-setting began in May and a high yield was expected
but nearly all of the fruits were damaged by caterpillars before
reaching maturity.
In Puerto Rico, no diseases were evident. In
the Bahamas, only a slight incidence of leaf spot was observed. In
Mexico, the husk tomato and the common tomato are both subject to a
disease called chino or chahuixtle which occurs in irrigated plantings
in Morelos. It is transmitted by the mosquita blanca, Trialeurodes vaporariorum.
Food Uses This
species, in contrast with the cape gooseberry, is used more largely as
a vegetable than as a dessert fruit, though it is often consumed ripe,
raw, out-of-hand. In Mexico, it is generally made into a sauce, salsa
verde, for meats, alone or together with green chili peppers.
Suggestions for use distributed by Iowa State College include recipes
for stewing, frying, baking, cooking with chopped meat, making into
soup, marmalade and dessert sauce. The fruit is an excellent addition
to salads and curries. It has been utilized commercially for jam in
Australia but the product is there considered inferior to that made
from the cape gooseberry. The fruits, canned whole in Mexico, are sold
domestically and in the western United States.
Food Value
Food
Value Per
100 g of Edible Portion* |
Moisture | 90.4-91.7 g |
Protein
|
0.171-0.7 g |
Fat |
0.6 g |
Carbohydrates |
5.8 g |
Fiber |
0.6-1.7 g |
Ash |
0.6-0.69 g |
Calcium |
6.3-10.9 mg |
Magnesium |
23 mg |
Phosphorus |
21.9-40 mg |
Phytin Phosphorus |
7 mg |
Iron |
0.57-1.4 mg |
Ionisable Iron |
1.0 mg |
Sodium |
0.4 mg |
Potassium | 243 mg | Copper | 0.09 mg | Sulfur | 27 mg | Chloride | 14 mg | Carotene (Vitamin A) | 80 I.U. or 0.061-0.074 mg | Thiamine | 0.054-0.106 mg | Riboflavin | 0.023-0.057 mg | Niacin | 2.1-2.7 mg | Ascorbic Acid | 2-4.8 mg |
*According
to analyses of the husked fruit made in Guatemala and India. |
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Medicinal
Uses It is said in Mexico that a decoction of the calyces will cure diabetes.
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