Chiku or Sapota (Manilka zapota)

Name and botany

Sapota (Manilkara zapota van Royen) or bully tree is commonly called sapota in India is a delicious fruit, long-lived, evergreen tree native to southern Mexico, Central America and the West Indies. It is mainly grown for its fruits, while in south east Mexico, Guatemala, British Honduras and other countries chickle is commercially produced. The unripe fruit and bark yield milky white latex which solidifies on exposure to air and this forms the base for making chickle. Immature fruits are astringent, while ripe fruits are sweet smelling and delicious. The mature fruits are used for making mixed jams and they provide a valuable source of raw material for the manufacture of industrial glucose, pectin and natural fruit jellies. They are also canned as slices. It is grown in huge quantities in India, Mexico and was introduced to the Philippines during Spanish colonisation.

a) Taxonomy:

Manikara zapota or chiku is classified in the division Magnoliophyta, class Magnoliopsida, order Ebanales and family Sapotaceae or the 'naseberry family'. Sapotaceae includes trees or shrubs comprising about 70 genera and 800 species. The genus Manilkara comprises some 85 species of tropical and warm-temperate, fruit-bearing plants. The basic chromosome number (x) = 7, but ranges between 9 and 13 in the Sapottaceae family.

b) Common names:

Chikoo or "chiku - Pakistan & India
Sapota - some parts of India (Tamil Nadu, Karnataka)
sobeda/sofeda - Eastern India and Bangladesh
Sabudheli - Maldives
Sawo - Indonesia
lng mt or xa po che - Vietnam
lamoot - Thailand, Laos and Cambodia
sapodilla - Guyana and Trinidad & Tobago
naseberry - Jamaica
sapathilla or rata-mi - Sri Lanka
zapote - Colombia, El Salvador
nispero - Costa Rica, Cuba, Puerto Rico, Nicaragua and Dominican Republic
dilly - The Bahamas
naseberry - the rest of the Caribbean
sapoti - Brazil and Haiti
chico or tsiko - Philippines
chico sapote - Mexico, Hawaii, southern California and southern Florida
ciku - Malaysia 

c) Synonyms:

Achras sapota Fosb.; Manilkara zapotilla Gilly; Manilkara achras (Mill) Fosberg; Achras zapota L.; Sapota achras Mill

d) Botanical description

Tree: Sapota grows to 3-4 m tall. It is wind-resistant and the bark is rich in white, gummy latex called chickle. The trees can only survive in warm, typically tropical environments, dying easily if the temperature drops below freezing. From germination, the sapota tree will usually take anywhere from 5-8 years to bear fruit. The sapota trees yield fruit twice a year, though flowering may continue year round.

In Vietnam, the most famous varieties of sapota are grown in Xuan Dinh village, Hanoi.

Tree of 'Silas Woods' sapodilla		A whorl of sapodilla leaves

Leaves: The ornamental leaves are light green to pinkish when newly emerged, turning dark green and glossy at maturity. They are alternate, elliptic to ovate, spirally clustered at the tips of the forked twigs, 7-15 cm long, with an entire margin .

Flower: The off-white hermaphrodite flowers with three brown, hairy outer sepals and three inner sepals are inconspicuous and bell-like borne on slender stalks at the leaf bases with a six-lobed pale green corolla.The whorl of six functional stamens is attached to the corolla opposite the corolla lobes. The ovary is superior, contains a 10-lobes ovule and has a single style.The floral formula is .

The flowers are borne in the leaf axils and 9.5 mm in diameter. The flowers are usually aggregated in inflorescences or panicles and the majority of them anthesises during later part of the morning. Flowers located at he base of the panicles are older and open earlier than those younger ones at the apical ends (Sarip, 2008).

Chiku or sapota flowers

Flowering and fruit production:

Flowering: Grafted sapotas usually begin flowering at 3-4 years of age. The tree has a free but multi-cyclical flowering habit with two annual peak blooms. Time and intensity of peak blooms are influenced by both genetic and agro-climatic factors as such there are wide variations in flowering behavior among cultivars as observed in Malaysia. Flowering and fruiting can occur concurrently since sapotas do not exhibit biennial flowering. In Malaysia, two peaks of prolific flowering occur annually in overlapping fasfion over the months of February-May and September-December. A season of peak flowering in sapotas usually lasts 2-3 months or longer.

Fruit set and yield: The fruit set is the most important factor which determines the yield. Problems of shedding of flowers and fruits and low fertility in sapota really affects the yield.The great variability in fruit set may be due to differences in flower abortion or fruit drop. Fruit set is highly variable, even within a cultivar. The fruit drop during the course of fruit development is quite small. However, flowers situated at the base of inflorescence opened and set into fruits earlier. Such early fruits developed rapidly and the remaining, which set relatively late, often dropped down which can be a very serious problem in sapota. The major period of fruit drop occurs in the first five weeks following fruit set and as little as 1.6% of the flowers produced by a tree may develop into fruit (Relekar et al. 1991). Evidently, fruit set and yield vary between clones occur in Malaysian clones such as, 'Betawi', 'Subang' and 'Mega'; Floridian cultivar 'Prolific', the Philippine's cultivar 'Ponderosa' and the Indian's cultivar 'Kalipatti' (Sarip,2002 c; Gonzalez and Feliciano, 1953; Mulla and Desle, 1990).

Cross-pollination with pollen from 'Subang' resulted in a high fruit set of 55-80% in 'Mega' cultivar, whereas only 10.2% fruit set when it is self-pollinated (Sarip, 2008). Gonzalez and Feliciano (1953) suggested that tree vigor may be related to flower production and fruit set .

Use of growth regulators has been found to be beneficial. Several growth regulators such as GA3, etherel, cycocel, and planofix (a NAA preparation) and SADH have been tried as spray solutions on the inflorescence before and again at the pea stage on sapotas. Of all the regulators, SADH at 100 ppm resulted in the highest fruit set and planofix at 300 ppm resulted in the highest fruit retention and largest fruits on cultivar 'Cricket Ball' (Das and Mahapatra, 1975). Spraying with GA 3 @ 50-100 ppm at the time of flowering is quite effective for getting better fruit set and also preventing fruit drop.

Self-incompatibility: Sapotas are largely self-compatible and cross-pollination is essential for high fruit set which basically depends on tree vigor (Piatos and Knight, 1975).

Pollination: Reddi's study (1989) showed several traits which indicated that wind is not an important pollinating agent, nor are large insects. This study also shows that sapodilla flowers are not self-pollinating, although pollen transfer is generally limited to a single tree unless trees are closely spaced. This information would provide evidence that sapodilla is not self-incompatible as previously suggested. Pollen size and viability are quite variable between cultivars, possibly causing the varied results in fruit set (Minhas and Sandhu 1985).

Thrips (Thrips hawaiiensis Morgan and Haplothrips tenuipennis Bagnall) has been reported to be the principal pollinator for spotas in India (Reddi, 1989). They collect and live on pollen grains, nectar and stigmatic exudations. They transfer the pollens while feeding them to other flowers when food reserves are exhausted. Bees also pollinate sapotas but they considered inefficient since they carry very little pollen. Trigona thoracia, ants (Componotus sp.) and Apis florae are reported to be casual visitors of sapota flowers in Malaysia (Sarip and Badri, 2005).

Thrips hawaiiensis		Trigona thoracia

Apis florae		Red ants (Componotus sp.)

Fruit: The fruit is variously described as 'a small potato', 'a small tomato', 'a round kiwi fruit', or 'a soft elongated tan egg'. Fruit development follows a sigmoidal pattern (Abdul-Karim et al. 1987). The initial growth phase is due to cell division and involves maturation of the embryo within the fruit. A phase of greatly reduced growth follows, until a second rapid growth phase occurs, during which time growth is due to cell enlargement. This second growth phase is the time when maximum growth occurs, between 5 and 7.5 months from fruit set (Lakshminarayana and Subramanyam 1966). The fruit are suitable for harvesting after the first growth phase, although higher quality fruit are obtained if they are harvested following the second growth phase, when there is a dramatic increase in sugar content of the fruit.

The fruit is a large ellipsoid berry, 4-8 cm in diameter, very much resembles a smooth-skinned potato and containing 2-5 seeds. The fleshy fruit has rough yellow, brown or reddish skin with brown scaly covering. Inside, its flesh ranges from a pale yellow to an earthy brown color with a grainy texture (caused by occurrence of hard stone-cells or sclerids among the parenchymatous tissues) akin to that of a well-ripened pear (Sarip, 1991). The fruit is best eaten when the flesh is ripe and. it is exceptionally sweet and very tasty, with what can be described as a malty flavor, the scent of honey, jasmine, lily of the valley and that of brown sugar, texture of cinnanmon, apple and pear.

Sapota fruit showing seeds

Many believe the flavor bears a striking resemblance to caramel. The fruits are a good source of sugar which ranges from 12-14%. The unripe fruit is hard to the touch and contains high amounts of saponin, which has astringent properties similar to tannin, drying out the mouth. The fruit has a high latex content and does not ripen until picked.

Seeds: The seeds are black and resemble beans, with a hook at one end that can catch in the throat if swallowed. Unlike most of tropical fruit, sapodilla seeds remain viable for several years if kept dry. The seed number per unit fruit ranges from 1 to 9 and the round fruits have more seeds than the oval. The fruit shape may also be influenced by the way of distribution of seeds aroung the placenta compared with oval fruits.

Sapota seeds

-- Top --