The guava (Psidium guajava Linn.) is one of the distributed fruit tree crop in the tropics (like the Philippines) and subtropics and found to be indigenous to the American tropics. It has a great potential for extensive commercial production because of its ease of culture, high nutritional value and popularity of processed products. Most common areas where guavas are grown in abundance are: open areas, second-growth forests, backyard or as a part of a mixed orchard. However, at present, there are no existing records for big planting and production of guava in the Philippines.
The fruit of guava is very rich in Vitamin C, which is substantially higher than what is found in citrus. It is also a good source of Vitamin A and other important elements. The fruit contains a large amount of citric, lactic, malic, oxalic and acetic acids and trace amount of formic acid.
The ripe fruit is usually eaten as dessert. It can also be utilized in many ways for making jellies, jam, paste, juice, baby foods, puree, beverage base, syrup, wine and other processed products. It may be eaten sliced with cream and sugar and as ingredient in cakes and pies. It is also used in dishes like “sinigang”.
Some parts of guava tree have medicinal and commercial usefulness. The bark and leaves are used in childbirth to expel the placenta. The leaves can be made into tea and astringent decoction can cure stomachache and act as vermifuge. When crushed or chewed, it is used for toothache treatment; pounded leaves may also be applied locally for rheumatism; can also be used for dyeing and tanning. The bark is sometimes used in complex cosmetics for hystero-epilepsy. Its wood is moderately strong and durable indoor and useful for handle and in carpentry and turnery.
Varieties / Strains
Supreme – The Supreme varieties from Florida. It is generally high yielding and produces a thick white flesh fruit of good quality for preserving or eating fresh. Fruit shape is ovate with distinct corrugation, 6.3 cm long, 5.5 cm in diameter and weighing 65 grams. The three is moderately prolific and regular bearing. When fully ripe, the fruit is bright yellow in color. The flavor in the inner pulp is sweet but the outer skin is slightly bitter and possesses a distinct strawberry wine odor, which is slightly astringent. It is moderately resistant to anthracnose and fruitfly but susceptible to leaf folder and aphids.
Red Indian Rolfs and Ruby – the fruit is ovate, 6.5 cm long, 5 cm in diameter with thin, smooth, medium green skin, weighing 75 grams. The fruit pulp is about 10 mm deep and red when fully ripe and has less pronounced corrugation. It is large seeded, sparsely populated but very sweet, juicy, crunchy and possesses a strong aroma. The tree is very prolific, regular bearing but easily attack by bats, moderately to anthracnose and oriental fruitfly.
Crosses between Ruby and Supreme – a large, white flesh variety from California, U.S.A.
Seedless variety – this variety has a fleshy layer, thick, that almost no seed cavity remained.
Goyena Quezo de Bola (NSIC 02 Gv-01) – this is NSIC guava variety approved in 2002, being a prolific yielder possessing yellowish green color of skin, finely smooth texture with pleasant aroma and weigh 575 g/fruit.
The other outstanding varieties grown in the Philippines are Bangkok, Java, Vietnamese and Hawaiian.
Soil and Climatic Requirement
Soil – guava does well on different soils from open sand to rather compact clay; from strongly acid (pH 4.5) to medium alkaline (pH 8.2) For good fruit production, guava should be grown in
rich, deep, well drained soils high in organic matter.
Climate – a rather dry climate is favorable for guava production. It may thrive best in the tropics at elevation from sea level to 5,000 feet with a tropical or near tropical temperature requirements.
Seed germination and care of seedlings – guava seeds should be thoroughly cleaned soon after extraction from the fruits. It is necessary to treat the seeds with fungicides to prevent damping off.
They should be planted early to ensure high germination. Germinated seeds in beds or boxes with a medium of fine sand or an equal mixture of sand and topsoil. Sow them evenly in the furrows 2-3 cm apart and lightly cover with soil 0.5 ? 1.0 cm deep. Water regularly to keep the soil moist.
Protect the seedlings against insect pests and diseases by spraying insecticides and/or fungicides. A month after emergence or when the first true leaves have formed transplant them in individual containers, like polybags using medium clay loam soil mixed with compost. Partial shading is necessary until the plant has recovered its growth. The plant is ready for planting or as rootstocks after one year
Propagation – guava is usually propagated by seeds. It can be propagated asexually through root suckers, root cutting, grafting, marcotting, budding, grafting and inarching.
Seed Propagation – propagation of guava is nearly always by seeds. Guavas are open-pollinated producing seedlings, which are highly variable in character. Variability in seedlings can be minimized by hand self-pollination or individual flowers.
Root suckers and root cuttings – the use of root suckers is probably the oldest method of asexually propagating guava. Root suckers are induced by severing roots to a few feet from the base of the plants and these are transferred when roots and shoots are established. Root cutting is done by cutting about 12-20 cm long parts of any butt very small or very large roots. These can be induced to sprout and form new plants provided it is placed in a suitable medium in a well-drained propagating bed. Both the use of root suckers and root cuttings are relatively slow methods of propagating guava.
Budding – an efficient vegetative propagation is by budding selected variety on seedling rootstock. Both the patch bud and forkert techniques are recommended onto seedling rootstock. The diameter of seedling stock and budwood should be from 15-25 mm. Budwood should be mature, bark no longer green. Condition the budwood by cutting off the leaves of selected branches 10-14 days before removing the branches for budwood. During this period the buds become more enlarged and grow more readily after budding.
Air layering – for this method, low branches of guava are bent down, about 12 – 15 cm of the branch is covered with soil and kept damp to induce root formation.
Stem cuttings – propagation by stem cuttings is made from the young wood at the end of the branches. These are rooted in sandy loam soil in propagating bed in a nursery house or shed. Guava stem cuttings treated with Indole Butyric Acid (IBA) or Napthalene Acetic Acid (NAA) proved to be successful for rooting and produce numerous and vigorous roots.
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