Eriobotrya japonica (Thunb.) Lindley

Eriobotrya japonica (Thunb.) Lindley

Family

Rosaceae

Synonyms

None

Vernacular Names

Malaysia, Indonesia Lokwat, papalaan (Sundanese).
English Loquat.
Cambodia Tôn leap.
Thailand Lokhwot, pee-pae.
Vietnam Ti ba diêp, so’n trà nhatban’, nhót tây.
French Neflier du Japon.

Geographical Distributions

Eriobotrya japonica is most probably originated in south-eastern China and has been cultivated there and also in Japan since antiquity. It is now found throughout the subtropics and tropics and grown commercially not only in China and Japan, but also in the Mediterranean region, Australia, South Africa, South America, California (United States) and India. In Southeast Asia, it is only grown in home gardens at higher altitudes.

Description

E. japonica is an evergreen shrub or small tree that can grow up to 5-10 m tall, with a straight low-branched trunk, a dense rounded crown and rusty-hairy branchlets.

The leaves are arranged alternately, oblong-lance-shaped, measuring 12-30 cm x 3-8 cm, remotely dentate, dark glossy green above, rusty hairy beneath, stiff and with prominent lateral veins that run to sharp teeth on the wavy margins. The petiole measures up to 5 mm long. The stipules are subulate and persistent.

The inflorescences are in panicles, measure 10-20 cm long, with 80-150-flowered and rusty pubescent. The flowers are sessile, measuring 15-20 mm in  and fragrant. The ovate sepal lobes are 5 densely woolly and persistent on top of the fruit. There are 5 white to creamy petals and obovate. There are about 20 stamens, with 2-5 styles, inferior ovary and with 2-5-celled.

The fruit is a spherical ovoid pome, measuring 3-8 cm x 2-5 cm, pale yellow to deep orange and with densely pubescent. The pericarp is fleshy. There are 1-5 dark brown seeds and measure about 2 cm long.

Ecology / Cultivation

The ecology of E. japonica is unusual as the natural cropping season and summer is the season of rest. Hence, mild humid winters are necessary, although flowers and fruits can stand light frost and the tree survives at temperatures as low as -10°C. When insolation is strong, the fruit clusters are bagged to prevent sunburn (purple stains on the fruit in Brazil). On the other hand, the fruit remains sour where sunshine is lacking (northern Tanzania). There should be sufficient moisture for a good post-harvest flush, but thereafter limiting factors (low moisture and nutrient levels, competition from a cover crop) should impose quiescence until the time has come for the flush that carries the flowers for the next crop. It is not known what triggers bloom at the right time, but it seems likely that progressive leaf fall during the quiescent period plays an important role. The suitable seasons with mild humid conditions are generally found in the tropical highlands at elevations of 700-2000 m. E. japonica grows well in these highlands, in fact often too well, leading to poor flowering and fruiting. It is not clear what distinguishes the highlands where the crop is grown successfully; even in the prominent monsoon climate of East Java, the growth rhythm tends to become asynchronous.

E. japonica also grows well in a wide range of soils, preferring acid over alkaline soils growth is poor in saline soils. The trees require a good drainage and protection from the sun for the surface roots. The trees are sometimes planted to mark the borders of fields, but sheltered locations are important for fruit production.

Line Drawing / Photograph

Eriobotrya_japonica

References

  1. Plant Resources of South-East Asia No. 2: Edible fruits and nuts.