From the book
Fruits of Warm Climates
by Julia F. Morton
Guava
Psidium
guajava L.
MYRTACEAE
One of the most gregarious of fruit trees, the guava, Psidium guajava
L., of the myrtle family (Myrtaceae), is almost universally known by
its common English name or its equivalent in other languages. In
Spanish, the tree is guayabo, or guayavo, the fruit guayaba or guyava.
The French call it goyave or goyavier; the Dutch, guyaba, goeajaaba;
the Surinamese, guave or goejaba; and the Portuguese, goiaba or
goaibeira. Hawaiians call it guava or kuawa. In Guam it is abas. In
Malaya, it is generally known either as guava or jambu batu, but has
also numerous dialectal names as it does in India, tropical Africa and
the Philippines where the corruption, bayabas, is often applied.
Various tribal names–pichi, posh, enandi, etc.–are employed
among the Indians of Mexico and Central and South America.
Plate L: GUAVA, Psidium
guajava
Description
A
small tree to 33 ft (10 m) high, with spreading branches, the guava is
easy to recognize because of its smooth, thin, copper-colored bark that
flakes off, showing the greenish layer beneath; and also because of the
attractive, "bony" aspect of its trunk which may in time attain a
diameter of 10 in (25 cm). Young twigs are quadrangular and downy. The
leaves, aromatic when crushed, are evergreen, opposite, short-petioled,
oval or oblong-elliptic, somewhat irregular in outline; 2 3/4 to 6 in
(7-15 cm) long, 1 1/5 to 2 in (3-5 cm) wide, leathery, with conspicuous
parallel veins, and more or less downy on the underside. Faintly
fragrant, the white flowers, borne singly or in small clusters in the
leaf axils, are 1 in (2.5 cm) wide, with 4 or 5 white petals which are
quickly shed, and a prominent tuft of perhaps 250 white stamens tipped
with pale-yellow anthers.
The fruit, exuding a strong, sweet,
musky odor when ripe, may be round, ovoid, or pear-shaped, 2 to 4 in
(5-10 cm) long, with 4 or 5 protruding floral remnants (sepals) at the
apex; and thin, light-yellow skin, frequently blushed with pink. Next
to the skin is a layer of somewhat granular flesh, 1/8 to 1/2 in
(3-12.5 mm) thick, white, yellowish, light- or dark-pink, or near-red,
juicy, acid, subacid, or sweet and flavorful. The central pulp,
concolorous or slightly darker in tone, is juicy and normally filled
with very hard, yellowish seeds, 1/8 in (3 mm) long, though some rare
types have soft, chewable seeds. Actual seed counts have ranged from
112 to 535 but some guavas are seedless or nearly so.
When immature and until a very short time before ripening, the fruit is
green, hard, gummy within and very astringent.
Origin and
Distribution
The
guava has been cultivated and distributed by man, by birds, and sundry
4-footed animals for so long that its place of origin is uncertain, but
it is believed to be an area extending from southern Mexico into or
through Central America. It is common throughout all warm areas of
tropical America and in the West Indies (since 1526), the Bahamas,
Bermuda and southern Florida where it was reportedly introduced in 1847
and was common over more than half the State by 1886. Early Spanish and
Portuguese colonizers were quick to carry it from the New World to the
East Indies and Guam. It was soon adopted as a crop in Asia and in warm
parts of Africa. Egyptians have grown it for a long time and it may
have traveled from Egypt to Palestine. It is occasionally seen in
Algeria and on the Mediterranean coast of France. In India, guava
cultivation has been estimated at 125,327 acres (50,720 ha) yielding
27,319 tons annually.
Apparently it did not arrive in Hawaii
until the early 1800's. Now it occurs throughout the Pacific islands.
Generally, it is a home fruit tree or planted in small groves, except
in India where it is a major commercial resource. A guava research and
improvement program was launched by the government of Colombia in 1961.
In 1968, it was estimated that there were about 10 million wild trees
(around Santander, Boyacá, Antioquia, Palmira, Buga, Cali and
Cartago) bearing, 88 lbs (40 kg) each per year and that only 10% of the
fruit was being utilized in processing. Bogotà absorbs 40% of
the production and preserved products are exported to markets in
Venezuela and Panama.
Brazil's modern guava industry is based on
seeds of an Australian selection grown in the botanical garden of the
Sao Paulo Railway Company at Tatu. Plantations were developed by
Japanese farmers at Itaquera and this has become the leading
guava-producing area in Brazil. The guava is one of the leading fruits
of Mexico where the annual crop from 36,447 acres (14,750 ha) of
seedling trees totals 192,850 tons (175,500 MT). Only in recent years
has there been a research program designed to evaluate and select
superior types for vegetative propagation and large-scale cultivation.
In
Florida, the first commercial guava planting was established around
1912 in Palma Sola. Others appeared at Punta Gorda and Opalocka. A
40-acre (16 ha) guava grove was planted by Miami Fruit Industries at
Indian-town in 1946. There have been more than two dozen guava jelly
manufacturers throughout the state. A Sarasota concern was processing
250 bushels of guavas per day and a Pinellas County processor was
operating a 150-bushel capacity plant in 1946. There has always been a
steady market for guava products in Florida and the demand has
increased in recent years with the influx of Caribbean and Latin
American people.
The guava succumbs to frost in California
except in a few favorable locations. Even if summers are too
cool–a mean of 60° F (15.56° C)–in the coastal
southern part of the state, the tree will die back and it cannot stand
the intense daytime heat of interior valleys.
In many parts of
the world, the guava runs wild and forms extensive
thickets–called "guayabales" in Spanish–and it overruns
pastures, fields and roadsides so vigorously in Hawaii, Malaysia, New
Caledonia, Fiji, the U.S. Virgin Islands, Puerto Rico, Cuba and
southern Florida that it is classed as a noxious weed subject to
eradication. Nevertheless, wild guavas have constituted the bulk of the
commercial supply. In 1972, Hawaii processed, for domestic use and
export, more than 2,500 tons (2,274 MT) of guavas, over 90% from wild
trees. During the period of high demand in World War II, the wild guava
crop in Cuba was said to be 10,000 tons (9,000 MT), and over 6,500 tons
(6,000 MT) of guava products were exported.
Cultivars
Formerly,
round and pear-shaped guavas were considered separate species–P.
pomiferum L. and P. pyriferum L.–but they are now recognized as
mere variations. Small, sour guavas predominate in the wild and are
valued for processing.
'Redland',
the first named cultivar in Florida, was developed at the University of
Florida Agricultural Research and Education Center, Homestead, and
described in 1941. Very large, with little odor, white-fleshed and with
relatively few seeds, it was at first considered promising but because
of its excessively mild flavor, low ascorbic acid content, and
susceptibility to algal spotting, it was abandoned in favor of better
selections.
'Supreme'
came next, of faint odor, thick, white flesh, relatively few, small
seeds, high ascorbic acid content and ability to produce heavy crops
over a period of 8 months from late fall to early spring.
'Red Indian',
of strong odor, medium to large size, round but slightly flattened at
the base and apex, yellow skin often with pink blush; with medium
thick, red flesh of sweet flavor; numerous but small seeds; agreeable
for eating fresh; fairly productive in fall and early winter.
'Ruby',
with pungent odor, medium to large size; ovate; with thick, red flesh,
sweet flavor, relatively few seeds. An excellent guava for eating fresh
and for canning; fairly productive, mainly in fall and early winter.
'Blitch'
(a seedling which originated in West Palm Beach and was planted at
Homestead)–of strong odor, medium size, oval, with light-pink
flesh, numerous, small seeds; tart, pleasant flavor; good for jelly.
'Patillo'
(a seedling selection at DeLand propagated by a root sucker and from
that by air-layer and planted at Homestead)–of very mild odor,
medium size, ovate to obovate, with pink flesh, moderate number of
small seeds; subacid, agreeable flavor; good for general cooking. (As
grown in Hawaii it is highly acid and best used for processing).
'Miami Red'
and 'Miami White',
large, nearly odorless and thick-fleshed, were released by the
University of Miami's Experimental Farm in 1954.
In
early 1952, Dr. J. J. Ochse imported into Florida air-layers of a
seedless guava from Java. All died. In September 1953, the writer
received air-layers from Saharanpur, India. One survived and was turned
over to the Agricultural Research and Education Center, Homestead. Four
more were ordered from Coimbatore but arrived dead. William Whitman
brought in a grafted plant from Java in 1954 which grew well, fruited
and was the source of propagating material. In 1955, Whitman obtained a
plant of a seedless guava from Cuba and it bore its first fruit in
1957. Seedless guavas are the result of low fertility of pollen grains
and self-incompatibility. The fruits tend to be malformed and the trees
are scant bearers. Applications of gibberellic acid increase fruit
size, weight and ascorbic acid content but induce prominent ridges on
the surface.
Among early California cultivars were:
'Webber'
(formerly 'Riverside'), of medium-large size, pale-yellowish flesh,
good flavor and 9.5% sugar.
'Rolfs', of
medium size with pink flesh; of good quality and containing 9% sugar.
'Hart',
fairly large, with pale-yellow flesh, and 8% sugar content.
Currently, some rare fruit fanciers grow the Florida-developed 'Red Indian' and 'White Indian'; also 'Detwiler' and 'Turnbull'.
In
1975, a guava trial project was undertaken at the Maroochy
Horticultural Research Station in southeastern Queensland, beginning
with 5 strains from Hawaii. By 1981, 4 selections (GA9-39R1T2',
'GA11-56T7', GA11-56R5T2' and 'GA11-564T1') seemed to hold promise for
processing and 2 selections ('GA11-56T3' and 'GA11-56R1T1') for
marketing fresh. They were all vegetatively propagated and tested as to
performance. The green-skinned, acid, 'GA11-56' and another Hawaiian
selection, '1050', yellow-skinned and mild in flavor and odor, are
being grown commercially for processing in New South Wales.
In
India much attention is given the characteristics of local and
introduced guava cultivars and their suitability for various purposes.
Among common white-fleshed cultivars are:
'Apple Colour'–of
medium size, slightly oblate; deep-pink skin, creamy-white flesh,
moderate amount of seeds, very sweet flavor (0.34-2.12% acid, 9 to
11.36% sugar); heavy bearer; good keeping quality; good for canning.
'Behat Coconut'–large,
with thick white flesh, few seeds; poor for canning.
'Chittidar'–medium
to large, round-ovate, white-fleshed, mild acid-sweet flavor; bears
moderately well; keeps well; good for canning.
'Habshi'–of
medium size with thick, white flesh, few seeds; halves good for canning.
'Lucknow 42'–of
medium size, roundish, with creamy-white, soft flesh; sweet, pleasant
flavor; very few seeds; good quality; bears heavily; keeps fairly well;
not suitable for canning.
'Lucknow 49'–medium-large
with cream-white, thick flesh, few seeds; acid-sweet; good quality;
heavy bearer; high in pectin and good for jelly; halves good for
canning.
'Safeda'–of
medium size, with very thin skin, thick, white flesh, few seeds.
Outstanding quality for canning. A famous guava, widely planted, but
susceptible to wilt and branches are brittle and break readily.
'Smooth Green'–of
medium size, with thick white flesh, few, small, hard seeds. Halves are
firm, good for canning.
'Allahabad'–large,
white-fleshed, with few, medium-sized, fairly hard seeds.
'Karela'–medium-large,
pear-shaped, furrowed, rough-skinned, with soft, granular, white flesh;
sweet, rich, pleasant flavor. Poor bearer. Not popular.
'Nagpur Seedless'–small
to medium, often irregular in shape; white-fleshed.
'Seedless'
(from Allahabad)–medium to large, pear-shaped to ovoid; with
thick white flesh, firm to soft, sweet. Light bearer; poor keeper.
A seedless type at Poona, India, was found to be a triploid with 33
chromosomes in place of the usual 22.
Other white-fleshed guavas with poor canning qualities are: 'Dharwar', 'Mirzapuri', 'Nasik', 'Sindh', and 'White Supreme X Ruby'.
Among red-fleshed cultivars in India there are:
'Anakapalle'–small,
with thin, red flesh, many seeds; not suitable for canning.
'Florida Seedling'–small,
with thin, red, acid flesh; many seeds; not suitable for canning.
'Hapi'–medium
to large, with red flesh.
'Hybrid Red Supreme'–large,
with thin, red, acid flesh; moderate amount of seeds; not suitable for
canning.
'Kothrud'–of
medium size with medium thick, red flesh; moderate amount of seeds; not
suitable for canning.
'Red-fleshed'–of
medium size with many (about 567) fairly soft seeds; high in pectin and
good for jelly; not suitable for canning.
Among other Indian cultivars are: 'Banaras',
'Dholka', 'Hasijka', 'Kaffree', and 'Wickramasekara'. The
latter is a small fruit and poor bearer.
Indian
breeders have crossed the guava with its dwarf, small-fruited relative,
P. guineense Sw., with a view to reducing tree size and enhancing
hardiness and yield.
In Egypt, a cultivar named 'Bassateen
El Sabahia'
has long been the standard commercial guava. Efforts have been made to
improve quality and yield and to this end selections were made from 300
seedlings. The most promising selection was tested and introduced into
cultivation in 1975 under the name 'Bassateen
Edfina'.
It is pear-shaped, of medium size, sometimes pink-blushed, with thick,
white flesh, few seeds, good flavor and higher ascorbic acid content
than the parent. It bears well over a long season.
In Puerto Rico, over 100 promising selections were under observation in
1963.
Numerous
cultivated clones identified only by number have been evaluated for
processing characters. Others have been tested and rated for rated for
resistance to Glomerella disease. Among the few named cultivars are 'Corozal Mixta', 'Corriente', and 'Seedling 57-6-79'.
In Trinidad, a large, white-fleshed type is known as 'Cayenne'.
In 1967, French horticulturists made a detailed evaluation of 11 guava
cultivars grown at the Neufchateau Station in Guadeloupe:
'Elisabeth'–large,
round, pink-fleshed, very acid; good for processing.
'Red' X 'Supreme'
X 'Ruby'–large,
ovoid, with deep-pink flesh; agreeable for eating fresh.
'Large White'–large,
round, white-fleshed; low sugar content, astringent; can be useful as
filler in preserves.
'Acid Speer'–large,
round, with pale-yellow flesh; acid; recommended only as source of
pectin.
'Red' X 'Supreme'
X 'Ruby' X 'White'–large to very
large, pear-shaped, with creamy-white flesh; good for eating fresh and
for juice and nectar.
'Pink Indian'–of
medium size, red-fleshed; agreeably acid; good for eating fresh and for
processing.
'Red Hybrid'–medium,
sub-ovoid, red-fleshed; medium quality.
'Supreme' X 'Ruby'–medium,
sub-ovoid, white-fleshed; unremarkable except for high productivity.
'Stone'–small,
ovoid, with deep-pink flesh; attractive and of agreeable flavor for
eating fresh.
'Supreme'–small,
ovoid, with pale-yellow, pink-tinged flesh; sweet; good for sherbet and
paste; very productive.
'Patricia'–very
small, ovoid, salmon-fleshed; attractive; good to eat fresh but quickly
loses its distinct strawberry flavor; good for sirup; very productive.
Between
1948 and 1969, 21 guava cultivars from 7 countries were introduced into
Hawaii. Some have been test planted and evaluated at the Waimanalo
Experimental Farm. Four sweet, white-fleshed, thick-walled cultivars
were rated as commercially desirable: 'Indonesian White', 'Indonesian Seedless',
'Lucknow 49',
and 'No. 6363'
(a 'Ruby' X 'Supreme'
hybrid from Florida). Lower ratings were given four others of this
group: 'Apple'
(too musky and seedy); 'Allahabad
Safeda' (too bumpy of surface); 'Burma' (too seedy)
and 'Hong Kong White'
(too seedy). Of the sweet, pink-fleshed, thick-walled cultivars
examined, 'Hong Kong Pink'
was preferred. Second choice was 'No.
6362' (a seedling of a 'Ruby' X' Supreme' cross in
Florida). 'No. 7199',
a seedling of a 'Stone Acid' X 'Ruby' cross in Florida, was considered
too musky. Among acid, non-musky, thick-walled guavas, 'Beaumont', a
Hawaiian selection, is large and pink-fleshed. 'Pink Acid'
(#7198), from a Florida cross of 'Speer' and 'Stone Acid', has
dark-pink flesh and few seeds. These cultivars are employed in breeding
programs in Hawaii. In 1978, a new cultivar, 'Ka Hua Kula',
selected from 1,200 seedlings of 'Beaumont', was released and
recommended for commercial guava puree. The fruit is large, with thick,
deep-pink flesh, and fewer seeds than 'Beaumont', and is less acid. It
is also a heavier bearer.
In Colombia, the cultivars 'Puerto
Rico', 'Rojo
Africano', and 'Agrio',
all yield over 2,200 fruits annually. Other high-yielding cultivars
being evaluated are 'White',
'Red', 'D-13', 'D-14', and 'Trujillo 2'.
Collecting
guava cultivars is a hobby of Mr. Arthur Stockdale, Finca Catalina,
Zitacuaro, Mexico. He is said to have some very superior selections in
his grove.
Pollination
The chief pollinator of guavas is the honeybee (Apis mellifera).
The amount of cross-pollination ranges from 25.7 to 41.3%.
Climate
The
guava thrives in both humid and dry climates. In India, it flourishes
up to an altitude of 3,280 ft (1,000 m); in Jamaica, up to 3,906 ft
(1,200 m); in Costa Rica, to 4,590 ft (1,400 m); in Ecuador, to 7,540
ft (2,300 m). It can survive only a few degrees of frost. Young trees
have been damaged or killed in cold spells at Allahabad, India, in
California and in Florida. Older trees, killed to the ground, have sent
up new shoots which fruited 2 years later. The guava requires an annual
rainfall between 40 and 80 in (1,000-2,000 mm); is said to bear more
heavily in areas with a distinct winter season than in the deep Tropics.
Soil
The
guava seems indiscriminate as to soil, doing equally well on heavy
clay, marl, light sand, gravel bars near streams, or on limestone; and
tolerating a pH range from 4.5 to 9.4. It is somewhat salt-resistant.
Good drainage is recommended but guavas are seen growing spontaneously
on land with a high water table–too wet for most other fruit
trees.
Propagation
Guava
seeds remain viable for many months. They often germinate in 2 to 3
weeks but may take as long as 8 weeks. Pretreatment with sulfuric acid,
or boiling for 5 minutes, or soaking for 2 weeks, will hasten
germination. Seedlings are transplanted when 2 to 30 in (5-75 cm) high
and set out in the field when 1 or 2 years old. Inasmuch as guava trees
cannot be depended upon to come true from seed, vegetative propagation
is widely practiced.
In Hawaii, India and elsewhere, the tree
has been grown from root cuttings. Pieces of any roots except the
smallest and the very large, cut into 5 to 10 in (12.5-20 cm) lengths,
are placed flat in a prepared bed and covered with 2 to 4 in (5-10 cm)
of soil which must be kept moist. Or one can merely cut through roots
in the ground 2 to 3 ft (0.6-0.9 m) away from the tree trunk; the cut
ends will sprout and can be dug up and transplanted.
By another
method, air-layers of selected clones are allowed to grow 3 to 5 years
and are then sawn off close to the ground. Then a ring of bark is
removed from each new shoot; root-inducing chemical is applied. Ten
days later, the shoots are banked with soil to a height 4 to 5 in
(10-12.5 cm) above the ring. After 2 months, the shoots are separated
and planted out.
Pruned branches may serve as propagating
material. Cuttings of half-ripened wood, 1/4 to 1/2 in (6-12.5 mm)
thick will root with bottom heat or rooting-hormone treatment. Using
both, 87% success has been achieved. Treated softwood cuttings will
also root well in intermittent mist. In Trinidad, softwood, treated
cuttings have been rooted in 18 days in coconut fiber dust or sand in
shaded bins sprayed 2 or 3 times daily to keep humidity above 90%. Over
100,000 plants were produced by this method over a 2-year period. Under
tropical conditions (high heat and high humidity), mature wood 3/4 to 1
in (2-2.5 cm) thick and 1 1/2 to 2 ft (45-60 cm) long, stuck into 1-ft
(30-cm) high black plastic bags filled with soil, readily roots without
chemical treatment.
In India, air-layering and inarching have
been practiced for many years. However, trees grown from cuttings or
air-layers have no taproot and are apt to be blown down in the first 2
or 3 years. For this reason, budding and grafting are preferred.
Approach
grafting yields 85 to 95% success. Trials have been made of the shield,
patch and Forkert methods of budding. The latter always gives the best
results (88 to 100%). Vigorous seedlings 1/2 to 1 in (1.25-2.5 cm)
thick are used as rootstocks.
The bark should slip easily to
facilitate insertion of the bud, which is then tightly bound in place
with a plastic strip and the rootstock is beheaded, leaving only 6 to 8
leaves above the bud. About a month later, an incision is made halfway
through 2 or 3 in (5-7.5 cm) above the bud and the plant is bent over
to force the bud to grow. When the bud has put up several inches of
growth, the top of the rootstock is cut off immediately above the bud.
Sprouting of the bud is expedited in the rainy season.
At the
Horticultural Experiment and Training Center, Basti, India, a system of
patch budding has been demonstrated as commercially feasible. A swollen
but unsprouted, dormant bud is taken as a 3/4 x 3/8 in (2 x l cm) patch
from a leaf axil of previous season's growth and taped onto a space of
the same size cut 6 to 8 in (15-20 cm) above the ground on a
1-year-old, pencil-thick seedling during the period April-June. After
the bud has "taken", 1/3 is cut from the top of the seedling; 2-3 weeks
later, the rest of the top is cut off leaving only 3/4 to 1 1/4 in
(2-3.2 cm) of stem above the bud. This method gives 80 to 90% success.
If done in July, only 70%. In Hawaii, old seedling orchards have been
topworked to superior selections by patch budding on stump shoots.
Culture
Guava
trees are frequently planted too close. Optimum distance between the
trees should be at least 33 ft (10 m). Planting 16 1/2 ft (5 m) apart
is possible if the trees are "hedged". The yield per tree will be less
but the total yield per land area will be higher than at the wider
spacing. Some recommend setting the trees 8 ft (2.4 m) apart in rows 24
ft (7.3 m) apart and removing every other tree as soon as there is
overcrowding. Where mass production is not desired and space is
limited, guava trees can be grown as cordons on a wire fence. Rows
should always run north and south so that each tree receives the
maximum sunlight. Exudates from the roots of guava trees tend to
inhibit the growth of weeds over the root system.
Light pruning
is always recommended to develop a strong framework, and suckers should
also be eliminated around the base. Experimental heading-back has
increased yield in some cultivars in Puerto Rico. In Palestine, the
trees are cut back to 6 1/2 ft (2 m) every other spring to facilitate
harvesting without ladders. Fruits are borne by new shoots from mature
wood. If trees bear too heavily, the branches may break. Therefore,
thinning is recommended and results in larger fruits.
Guava
trees grow rapidly and fruit in 2 to 4 years from seed. They live 30 to
40 years but productivity declines after the 15th year. Orchards may be
rejuvenated by drastic pruning.
The tree is drought-tolerant but
in dry regions lack of irrigation during the period of fruit
development will cause the fruits to be deficient in size. In areas
receiving only 15 to 20 in (38-50 cm) rainfall annually, the guava will
benefit from an additional 2,460 cm (2 acre feet) applied by means of 8
to 10 irrigations, one every 15-20 days in summer and one each month in
winter.
Guava trees respond to a complete fertilizer mix applied
once a month during the first year and every other month the second
year (except from mid-November to mid-January) at the rate of 8 oz (227
g) per tree initially with a gradual increase to 24 oz (680 g) by the
end of the second year. Nutritional sprays providing copper and zinc
are recommended thrice annually for the first 2 years and once a year
thereafter. In India, flavor and quality of guavas has been somewhat
improved by spraying the foliage with an aqueous solution of potassium
sulfate weekly for 7 weeks after fruit set.
Control of
Wild Trees
Large trees that have overrun pastures are killed in Fiji with 2,4-D
dicamba or 2,4,5-T in diesel fuel or old engine oil.
Extensive wild stands of young trees are best burned. Cutting results
in regrowth with multiple stems.
Cropping and
Yield
The
fruit matures 90 to 150 days after flowering. Generally, there are 2
crops per year in southern Puerto Rico; the heaviest, with small
fruits, in late summer and early fall; another, with larger fruits, in
late winter and early spring. In northern India, the main crop ripens
in mid-winter and the fruits are of the best quality. A second crop is
home in the rainy season but the fruits are less abundant and watery.
Growers usually withhold irrigation after December or January or
root-prune the trees in order to avoid a second crop. The trees will
shed many leaves and any fruits set will drop. An average winter crop
in northern India is about 450 fruits per tree. Trees may bear only
100-300 fruits in the rainy season but the price is higher because of
relative scarcity despite the lower quality. Of course, yields vary
with the cultivar and cultural treatment.
Experiments have shown
that spraying young guava trees with 25% urea plus a wetting agent will
bring them into production early and shorten the harvest period from
the usual 15 weeks to 4 weeks.
Handling and
Keeping Quality
Ripe
guavas bruise easily and are highly perishable. Fruits for processing
may be harvested by mechanical tree-shakers and plastic nets. For fresh
marketing and shipping, the fruits must be clipped when full grown but
underripe, and handled with great care. After grading for size, the
fruits should be wrapped individually in tissue and packed in 1 to 4
padded layers with extra padding on top before the cover is put on.
They have been successully shipped from Miami to wholesalers in major
northern cities in refrigerated trucks at temperatures of 45° to
55° F (7.22°-12.78° C). It is commonly said that guavas
must be tree-ripened to attain prime quality, but the cost of
protecting the crop from birds makes early picking necessary. It has
been demonstrated that fruits picked when yellow-green and artificially
ripened for 6 days in straw at room temperature developed superior
color and sugar content.
Guavas kept at room temperature in
India are normally overripe and mealy by the 6th day, but if wrapped in
pliofilm will keep in good condition for 9 days. In cold storage,
pliofilm-wrapped fruits remain unchanged for more than 12 days.
Wrapping
checks weight loss and preserves glossiness. Unwrapped 'Safeda' guavas,
just turned yellow, have kept well for 4 weeks in cold storage at
47° to 50° F (8.33°-10° C) and relative humidity of
85-95%, and were in good condition for 3 days thereafter at room
temperature of 76° to 87° F (24°-44° C).
Fruits
coated with a 3% wax emulsion will keep well for 8 days at 72° to
86° F (22.2°-30° C) and 40 to 60% relative humidity, and
for 21 days at 47° to 50° F (8.3°-10° C) and
relative humidity of 85-90%. Storage life of mature green guavas is
prolonged at 68° F (20° C), relative humidity of 85%, less
than 10% carbon dioxide, and complete removal of ethylene.
Researchers
at Kurukshetra University, India, have shown that treatment of
harvested guavas with 100 ppm morphactin (chlorflurenol methyl ester
74050) increases the storage life of guavas by controlling fungal
decay, and reducing loss of color, weight, sugars, ascorbic acid and
non-volatile organic acids. Combined fungicidal and double-wax coating
has increased marketability by 30 days.
Australian workers
report prolonged life and reduced rotting in storage after a hot water
dip, but better results were achieved by dipping in an aqueous benomyl
suspension at 122° F (50° C). Higher temperatures cause some
skin injury, as does a guazatine dip which is also a less effective
fungicide.
Fruits sprayed on the tree with gibberellic acid
20-35 days before normal ripening, were retarded nearly a week as
compared with the untreated fruits. Also, mature guavas soaked in
gibberellic acid off the tree showed a prolonged storage life.
Trials
at Haryana Agricultural University, Hissar, India, showed that weekly
spraying with 1.0% potassium sulfate–1.6 gals (6 liters) per
tree–beginning 7 days after fruit set and ending just before
harvesting at the pale-green stage, delays yellowing, retains firmness
and flavor beyond normal storage life.
Food technologists in
India found that bottled guava juice (strained from sliced guavas
boiled 35 minutes), preserved with 700 ppm SO2, lost much ascorbic acid
but little pectin when stored for 3 months without refrigeration, and
it made perfectly set jelly.
Pests and
Diseases
Guava trees are seriously damaged by the citrus flat mite, Brevipalpus californicus
in Egypt. In India, the tree is attacked by 80 insect species,
including 3 bark-eating caterpillars (Indarbella
spp.) and the guava scale, but this and other scale insects are
generally kept under control by their natural enemies. The green shield
scale, Pulvinaria psidii,
requires chemical measures in Florida, as does the guava white fly,
Trialeurodes floridensis, and a weevil, Anthonomus irroratus,
which bores holes in the newly forming fruits.
The
red-banded thrips feed on leaves and the fruit surface. In India,
cockchafer beetles feed on the leaves at the end of the rainy season
and their grubs, hatched in the soil, attack the roots. The larvae of
the guava shoot borer penetrates the tender twigs, killing the shoots.
Sometimes aphids are prevalent, sucking the sap from the underside of
the leaves of new shoots and excreting honeydew on which sooty mold
develops.
The guava fruit worm, Argyresthia
eugeniella, invisibly infiltrates hard green fruits, and
the citron plant bug, Theognis
gonagia, the yellow beetle, Costalimaita ferruginea,
and the fruit-sucking bug, Helopeltis
antonii, feed on ripe fruits. A false spider mite, Brevipalpus phoenicis,
causes surface russeting beginning when the fruits are half-grown.
Fruit russeting and defoliation result also from infestations of
red-banded thrips, Selenothrips
rubrocinctus. The coconut mealybug, Pseudococcus nipae,
has been a serious problem in Puerto Rico but has been effectively
combatted by the introduction of its parasitic enemy, Pseudaphycus utilis.
Soil-inhabiting white grubs require plowing-in of an approved and
effective pesticide during field preparation in Puerto Rico.
There are other minor pests, but the great problems wherever the guava
is grown are fruit flies.
The guava is a prime host of the Mediterranean, Oriental, Mexican, and
Caribbean fruit flies, and the melon fly–Ceratitis capitata,
Dacus
dorsalis, Anastrepha
ludens, A.
suspensa, and Dacus
cucurbitae.
Ripe fruits will be found infested with the larvae and totally unusable
except as feed for cattle and swine. To avoid fruit fly damage, fruits
must be picked before full maturity and this requires harvesting at
least 3 times a week. In Brazil, choice, undamaged guavas are produced
by covering the fruits with paper sacks when young (the size of an
olive). Infested fruits should be burned or otherwise destroyed. In
recent years, the Cooperative Extension Service in Dade County,
Florida, has distributed wasps that attack the larvae and pupae of the
Caribbean fruit fly and have somewhat reduced the menace.
In Puerto Rico, up to 50% of the guava crop (mainly from wild trees)
may be ruined by the uncontrollable fungus, Glomerella cingulata,
which mummifies and blackens immature fruits and rots mature fruits. Diplodia natalensis may
similarly affect 40% of the crop on some trees in South India.
Fruits punctured by insects are subject to mucor rot (caused by the
fungus, Mucor hiemalis)
in Hawaii. On some trees, 80% of the mature green fruits may be ruined.
Algal spotting of leaves and fruits (caused by Cephaleuros virescens)
occurs in some cultivars in humid southern Florida but can be
controlled with copper fungicides. During the rainy season in India,
and the Province of Sancti Spiritus, Cuba, the fungus, Phytophthora parasitica,
is responsible for much infectious fruit rot. Botryodiplodia sp.
and Dothiorella
sp. cause stem-end rot in fruits damaged during harvesting. Macrophomina sp.
has been linked to fruit rot in Venezuela and Gliocladium roseum
has been identified on rotting fruits on the market in India.
In
Bahia, Brazil, severe deficiency symptoms of guava trees was attributed
to nematodes and nematicide treatment of the soil in a circle 3 ft (0.9
in) out from the base restored the trees to normal in 5 months. Zinc
deficiency may be conspicuous when the guava is grown on light soils.
It is corrected by two summer sprayings 60 days apart with zinc
sulphate.
Wilt, associated with the fungi Fusarium
solani and Macrophomina
phaseoli,
brings about gradual decline and death of undernourished 1-to
5-year-old guava trees in West Bengal. A wilt disease brought about by
the wound parasite, Myxosporium
psidii, causes the death of many guava trees, especially
in summer, throughout Taiwan. Wilt is also caused by Fusarium oxysporum
f. psidii
which invades the trunk and roots through tunnels bored by the larvae
of Coelosterna beetles. Anthracnose (Colletotrichum gloeosporioides)
may attack the fruits in the rainy season. Pestalotia psidii
sometimes causes canker on green guavas in India and rots fruits in
storage.
Severe losses are occasioned in India by birds and bats and some
efforts are made to protect the crop by nets or noisemakers.
Food Uses
Raw
guavas are eaten out-of-hand, but are preferred seeded and served
sliced as dessert or in salads. More commonly, the fruit is cooked and
cooking eliminates the strong odor. A standard dessert throughout Latin
America and the Spanish-speaking islands of the West Indies is stewed
guava shells (cascos de guayaba), that is, guava halves with the
central seed pulp removed, strained and added to the shells while
cooking to enrich the sirup. The canned product is widely sold and the
shells can also be quick-frozen. They are often served with cream
cheese. Sometimes guavas are canned whole or cut in half without seed
removal.
Bars of thick, rich guava paste and guava cheese are
staple sweets, and guava jelly is almost universally marketed. Guava
juice, made by boiling sliced, unseeded guavas and straining, is much
used in Hawaii in punch and ice cream sodas. A clear guava juice with
all the ascorbic acid and other properties undamaged by excessive heat,
is made in South Africa by trimming and mincing guavas, mixing with a
natural fungal enzyme (now available under various trade names),
letting stand for 18 hours at 120° to 130° F
(49°-54° C) and filtering. It is made into sirup for use on
waffles, ice cream, puddings and in milkshakes. Guava juice and nectar
are among the numerous popular canned or bottled fruit beverages of the
Caribbean area. After washing and trimming of the floral remnants,
whole guavas in sirup or merely sprinkled with sugar can be put into
plastic bags and quick-frozen.
There are innumerable recipes for
utilizing guavas in pies, cakes, puddings, sauce, ice cream, jam,
butter, marmalade, chutney, relish, catsup, and other products. In
India, discoloration in canned guavas has been overcome by adding 0.06%
citric acid and 0.125% ascorbic acid to the sirup. For pink sherbet,
French researchers recommend 2 parts of the cultivar 'Acid Speer' and 6
parts 'Stone'. For white or pale-yellow sherbet, 2 parts 'Supreme' and
4 parts 'Large White'. In South Africa, a baby-food manufacturer
markets a guava-tapioca product, and a guava extract prepared from
small and overripe fruits is used as an ascorbic-acid enrichment for
soft drinks and various foods.
Dehydrated guavas may be reduced
to a powder which can be used to flavor ice cream, confections and
fruit juices, or boiled with sugar to make jelly, or utilized as pectin
to make jelly of low-pectin fruits. India finds it practical to
dehydrate guavas during the seasonal glut for jelly-manufacture in the
off-season. In 1947, Hawaii began sea shipment of frozen guava juice
and puree in 5-gallon cans to processors on the mainland of the United
States. Since 1975, Brazil has been exporting large quantities of guava
paste, concentrated guava pulp, and guava shells not only to the United
States but to Europe, the Middle East, Africa and Japan.
Canned,
frozen guava nectar is an important product in Hawaii and Puerto Rico
but may be excessively gritty unless stone cells from the outer flesh
and skin are reduced by use of a stone mill or removed by centrifuging.
In South Africa, guavas are mixed with cornmeal and other ingredients
to make breakfast-food flakes.
Green mature guavas can be utilized as a source of pectin, yielding
somewhat more and higher quality pectin than ripe fruits.
| Food
Value Per
100 g of Edible Portion* |
| Calories |
36-50 |
| Moisture |
77-86 g |
| Crude Fiber |
2.8-5.5 g |
| Protein |
0.9-1.0 g |
| Fat |
0.1-0.5 g |
| Ash |
0.43-0.7 g |
| Carbohydrates |
9.5-10 g |
| Calcium |
9.1-17 mg |
| Phosphorus |
17.8-30 mg |
| Iron |
0.30-0.70 mg |
| Carotene (Vitamin A) |
200-400 I.U. |
| Thiamine |
0.046 mg |
| Riboflavin |
0.03-0.04 mg |
| Niacin |
0.6-1.068 mg |
| Vitamin B3 |
40 I.U. |
| Vitamin G4 |
35 I.U. |
*Analyses of whole ripe guavas. | |
|
Ascorbic
acid–mainly in the skin, secondly in the firm flesh, and little
in the central pulp–varies from 56 to 600 mg. It may range up to
350-450 mg in nearly ripe fruit. When specimens of the same lot of
fruits are fully ripe and soft, it may decline to 50-100 mg. Canning or
other heat processing destroys about 50% of the ascorbic acid. Guava
powder containing 2,500-3,000 mg ascorbic acid was commonly added to
military rations in World War II. Guava seeds contain 14% of an
aromatic oil, 15% protein and 13% starch. The strong odor of the fruit
is attributed to carbonyl compounds.
Other Uses
Wood:
The wood is yellow to reddish, fine-grained, compact, moderately
strong, weighs 650-750 kg per cubic meter; is durable indoors; used in
carpentry and turnery. Though it may warp on seasoning, it is much in
demand in Malaya for handles; in India, it is valued for engravings.
Guatemalans use guava wood to make spinning tops, and in El Salvador it
is fashioned into hair combs which are perishable when wet. It is good
fuelwood, and also a source of charcoal.
Leaves and
bark:
The leaves and bark are rich in tannin (10% in the leaves on a dry
weight basis, 11-30% in the bark). The bark is used in Central America
for tanning hides. Malayans use the leaves with other plant materials
to make a black dye for silk. In southeast Asia, the leaves are
employed to give a black color to cotton; and in Indonesia, they serve
to dye matting.
Wood flowers:
In Mexico, the tree may be parasitized
by the mistletoe, Psittacanthus
calyculatus Don, producing the
rosette-like malformations called "wood flowers" which are sold as
ornamental curiosities.
Medicinal Uses:
The roots, bark, leaves and immature fruits, because of their
astringency, are commonly employed to halt gastroenteritis, diarrhea
and dysentery, throughout the tropics. Crushed leaves are applied on
wounds, ulcers and rheumatic places, and leaves are chewed to relieve
toothache. The leaf decoction is taken as a remedy for coughs, throat
and chest ailments, gargled to relieve oral ulcers and inflamed gums;
and also taken as an emmenagogue and vermifuge, and treatment for
leucorrhea. It has been effective in halting vomiting and diarrhea in
cholera patients. It is also applied on skin diseases. A decoction of
the new shoots is taken as a febrifuge. The leaf infusion is prescribed
in India in cerebral ailments, nephritis and cachexia. An extract is
given in epilepsy and chorea and a tincture is rubbed on the spine of
children in convulsions. A combined decoction of leaves and bark is
given to expel the placenta after childbirth.
The leaves, in
addition to tannin, possess essential oil containing the sesquiterpene
hydrocarbons caryophyllene, b-bisabolene, aromadendrene, b-selinene,
nerolidiol, caryophyllene oxide and sel-11-en-4x -ol, also some
triterpenoids and b-sitosterol. The bark contains tannin, crystals of
calcium oxalate, ellagic acid and starch. The young fruits are rich in
tannin.
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