Botánica tropical


Flora de relevancia de África del oeste
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Mango

Mangifera indica


Anacardiaceae
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Nombre vernacular:

Manguier (fr), Mango tree (eng)

Origen y distribución geográfica
 El mango es supustamente originario de la región Indo-burmesa. Ha sido cultivado en la India desde hace miles de años pero se ha dispersado por el sudeste asiático hace unos 1500 años y en la costa este de África hace unos 1000 años aproximadamente. La expansión hacia Australia, América, el oeste africano y el resto del mundo se produjo en los últimos cientos de años. El mango es una planta simbólica del hinduismo.

Usos
 Alimento: El mango se cultiva principalmente por su fruto, que se puede comer inmaduro, muy popular en Tailandia y Filipinas para dar sabor a pescado; madura, la manera más común de disfrutar de esta deliciosa fruta o procesada; siropes, mermeladas, conservas agridulces, rodajas secas, encurtidos, zumos...La fruta tiene una forma ovalada, dorada, carnosa y rica en vitaminas A y C. El hueso del mango es usado como alimento en épocas de hambruna, se debe de cocer y tostar antes de comer para eliminar la astringencia. Las hojas de mango se usan como forraje para ganado pero en grandes cantidades pueden causar la muerte.
Apicultura: Es una planta muy importante para la producción apícola, sus flores, de finales de noviembre a finales de diciembre, secretan grandes cantidades de nectar.
Combustible: El valor calorífico de la madera del mango es  4200 kcal/kg lo cual hace una excelente madera para la producción de carbón y leña.
Medicina: Las hojas carbonizadas sirven para hacer un emplasto para sacar verrugas. Las semillas se usan para tratar catarros, diarrea y almorranas sangrantes. La corteza es homeostática, astringente y
antireumática.
La madera del mango se puede utilizar para construcción ligera, cajas, suelos o construcción de canoas. Pero la importancia estratégica de este árbol hace que muy raramente sea cortado para estos fines.
Descripción
El mango es un árbol de hoja perenne de hasta 20 metros de altura, con una copa en forma de paraguas. El tronco llega hasta casi un metro de diámetro en algunos casos. En el Sahel la altura raramente supera los 10 metros. El tronco es marrón con muchas fisuras finas, volviendose más oscuro, surcado. Un latex blancuzco se exuda desde el tronco.

Las variedades de mango difieren mucho en la calidad de la fruta. Desde las variedades de alta calidad (clones habitualmente) que tienen una carne amarilla/naranja, sin apenas fibras, muy dulce y jugosa a las variedades silvestres, que tienen un sabor a trementina y son muy fibrosas
Crecimiento y desarrollo
Growth and development  
The mango seedling (or seedlings in the case of polyembryonic seeds) emerges in 2 weeks and grows rhythmically from the start: a flush brings out the new shoot which extends in about 1 month time, after which the buds remain quiescent for shorter or longer periods. In a mature tree many twigs produce no extension growth for a year or longer, but in saplings most twigs flush up to 4 times per year if there is enough moisture. Flushes occur more or less synchronously depending upon the climate; during a long wet season the synchronization is gradually weakened. Leaves can remain functional for several years. The tree roots to a considerable depth, enabling it to find the moisture necessary for flowering/flushing during the dry season. Normally only the buds at the compressed shoot tip partake in extension growth and flowering. Vigour finds expression in shoots of larger size and in the leafing out of more — often up to 5 — lateral buds at the shoot tip. A seedling mango comes into bearing after 5—7 years, some terminal buds producing an inflorescence whereas other terminals extend a flush of shoots. With the onset of bearing, the number of flushes is reduced to 2 or 3, including the dry-season flush which coincides with flowering. Studies of several mango cultivars have revealed biennial flowering at the twig level, which means that shoots emerging from twigs which have flowered are unlikely to flower in their turn, even where flowering did not result in fruiting. Also, shoots of the last flush before flowering are less likely to break into bloom than twigs of previous flushes which have gone through much longer quiescent periods. In many Indian cultivars these tendencies are so strong that prolific bloom or late flushing necessarily lead to failure of the following bloom, thus leading to biennial bearing. It remains to be shown whether or not similar extremes occur in South-East Asian cultivars. The inflorescence can reach full bloom from the time of flower initiation in as little as 25—30 days. Considering that each flower is a transformed shoot, an inflorescence is essentially as complex as a sizeable tree; hence the rate of organogenesis leading to bloom is astounding. Presumably the preceding quiescent period somehow paves the way for this explosive floral development. The fruits also grow fast: they ripen after 3—4 months, some late cultivars after 5 months. Pollination is largely effected by insects (flies, bees); wind pollination is not very effective. Stigmas remain receptive for a short period only, mainly during the night and morning. Cross-pollination is recommended but polyembryonic cultivars in particular are often planted without pollinators. Fruit set is rather poor and variable, and losses due to premature drop occur right up to the harvest. Hence only about 1 out of 1000 perfect flowers can be expected to yield a fruit.
Ecology
The mango thrives both in the subtropics and the tropics. In the subtropics the cold months ensure excellent floral induction, but late frosts are a major risk: tender parts of the tree are killed by frost. In the tropics the mango grows almost anywhere up to 1200 m elevation, but for fruit production a prominent dry season lasting more than 3 months is necessary. A flowering flush is produced during the dry season, but — contrary to the subtropics — flowering is erratic and a yield-limiting factor. At elevations above 600 m in the tropics the climate becomes too cool for the commercial cultivars, the optimum temperature being around 24—27°C. Rainfall ranges from 750 to 2500 mm per year in tropical centres of production. Mangoes grow in a wide range of soils and moisture regimes. The trees are drought-tolerant, and on the other hand do not seem to suffer from occasional flooding. A deep (rooting depth 2.5 m) but rather poor soil is preferred; easy access to water and nutrients tends to stimulate growth at the expense of flowering. A high pH is less detrimental than acid soils, the preferred range being 5.5—7.


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