Will coconut grow in artificial medium eg.MS?

Question

Will coconut grow in artificial medium eg.MS?

Answer 1

The Coconut Palm in Florida1

Timothy K. Broschat and Jonathan H. Crane2

· Scientific Name: Cocos nucifera Linn.

· Family: Arecaceae

ORIGIN

Comparatively little is known about the origin and early distribution of the coconut palm, probably because it was so widely spread throughout the tropical areas of the world so many years ago. It is believed to be native to the Malay Archipelago or the South Pacific.

DISTRIBUTION

The coconut is widespread throughout the tropics, typically being found along sandy shorelines. It has been spread largely by man but also by natural means. The fruit can float for long distance and still germinate to form new trees after being washed ashore. Commercial plantings are confined to the tropical lowlands, but it will also fruit in a few warmer subtropical areas. In Florida it is successfully grown from Stuart on the east coast and Punta Gorda on the west coast, south to Key West.

IMPORTANCE

The coconut is the most extensively grown and used nut in the world and the most important palm. It is an important commercial crop in many tropical countries, contributing significantly to their economies. The chief product is copra, the source of coconut oil used for making soap, shampoo, cosmetics, cooking oils and margarine. Much of the fruit is consumed locally for food. The coconut palm more than any other plant, gives a tropical effect to the Florida landscape. It is highly valued as an ornamental but is also grown on a limited commercial basis in Florida for coco frio, a refreshing drink made from the water inside green coconuts.

DESCRIPTION

Tree. Large single-trunked palm tree with a smooth, columnar, light grayish brown trunk, and topped with a terminal crown of leaves. Tall varieties may attain a height of 80 to 100 feet (24 to 31 m) while dwarf varieties are shorter in stature. The trunk is slender and often swollen at the base. It is typically curved or leaning, but is erect in some cultivars.

Leaves. The pinnate leaves are feather-shaped, up to 18 feet (5.5 m) long and 6 feet (1.8 m) wide. The leaf stalks are 3 to 5 feet (0.9 to 1.5 m) in length and spineless.

Flowers. Male and female flowers are borne on the same inflorescence. The inflorescences emerge from canoe-shaped sheaths among the leaves and may be 2 to 3 feet (0.6 to 0.9 m) long and have 10 to 50 branchlets. Male flowers are small, light yellow, and are found at the ends of the branchlets. Female flowers are larger than male flowers, light yellow in color, and are found towards the base of the branchlets. Coconut palms begin to flower at about 4 to 6 years of age.

Fruit. Roughly ovoid, up to 15 inches (38 cm) long and 12 inches (30 cm) wide, composed of a thick, fibrous husk surrounding a somewhat spherical nut with a hard, brittle hairy shell. The nut is 6 to 8 inches 15 to 20 cm) in diameter and 10 to 12 inches 25 to 30 cm) long. Three sunken holes of softer tissue called "eyes" are at one end of the nut. Inside the shell is a thin, white, fleshy layer, about one inch thick at maturity, known as the "meat" or copra. The interior of the nut is hollow but partially filled with a watery liquid called "coconut milk". The meat is soft and jelly-like when immature but it becomes firm at maturity. The coconut milk is abundant in unripe fruits but it is gradually absorbed as ripening proceeds. The fruits are green at first turning brownish as they mature. Yellow varieties go from yellow to brown.

PRODUCTION

The coconut palm starts fruiting 6 to 10 years after the seed germinates and reaches full production at 15 to 20 years of age. It continues to fruit until it is about 80 years old with an annual production of 50 to 200 fruits per tree, depending on cultivar and climate. The fruits require about a year to develop and are generally produced regularly throughout the year.

CULTIVARS

Several cultivars of coconut palms are grown in Florida (Table 1 ). They differ in their petiole and fruit color, straightness (or crookedness) of the trunk, leaflet and leaf width, growth rates, presence or absence of a swollen trunk base or bole, adaptibility to Florida's soil conditions, and resistance to lethal yellowing disease. The 'Jamaican Tall' (='Atlantic Tall') is a rapid-growing variety with a swollen trunk base and crooked trunk. It is well-adapted to Florida. The 'Malayan Dwarf' cultivar has three color forms that differ in the color of the immature fruits and petioles (green, yellow, or gold). It is smaller and slower-growing than the 'Jamaican Tall' and has a narrow straight, non-swollen trunk. The 'Panama Tall' (='Pacific Tall') is a large, robust palm with a large diameter crooked and swollen trunk, rapid growth rate, and either green or bronze-colored fruits and petioles. The 'Maypan' is a hybrid between the 'Malayan Dwarf' and the 'Panama Tall' and resembles the 'Jamaican Tall' in appearance.

The 'Malayan Dwarf' cultivar and the hybrid 'Maypan' have been widely planted in Florida because of their reported resistance to lethal yellowing (LY), a fatal disease of coconut palms in Florida and parts of the Caribbean region. Although these varieties were originally believed to be highly resistant to this disease, long-term trials in Florida have revealed that they are only slightly less susceptible than the 'Jamaican Talls' they were intended to replace. The only cultivar in the United States that has been demonstrated in long-term studies to be resistant to LY is the 'Fiji Dwarf' (Niu Leka), a slow-growing variety with very broad leaves and leaflets. It can have either bronze or green fruits and petioles and has a very thick crooked trunk. It is well-adapted to Florida soils, but unfortunately is not yet commercially available.

PROPAGATION

Propagation is entirely from seed which are ready for planting if they produce an audible "sloshing" sound when shaken. The nuts are placed on their sides and buried to about one-half their thickness with sand or mulch. They may be planted in closely spaced rows in well-drained seedbeds or they may be planted directly into large pots. Germination is best under high temperatures (90 to 100 degrees F). Upon germination, the shoot and root emerge through the side or one end of the nut. Young palms, about 6 months old, can be transplanted directly into the field or be grown in pots in the nursery for a few more years.

CLIMATE AND SOILS

The coconut palm is typically found along tropical, sandy shorelines since it can tolerate brackish soils and salt spray. However, salt is not required for the growth of healthy plants and they can be successfully grown well inland. Coconut palms grow well in a wide range of soil types, provided they are well-drained, and a wide pH range, from 5.0 to 8.0. Successful growth requires a minimum average temperature of 72°F and an annual rainfall of 30 to 50 inches or more. The trees may be injured by cold when the temperature falls below 32°F (0°C). They require full sunlight and are tolerant to wind and temporary flooding.

PLANTING AND SPACING

Coconut palms may be planted at any time of the year but the warm, rainy summer months are best. The trees can be successfully transplanted at any period in their growth, provided they are properly handled. Preplanting soil preparation depends upon soil type and depth of the water table. In low lying areas, beds several feet high and wide should be constructed to prevent waterlogging of the root zone during wet periods. In some areas a hardpan in the soil profile may need to be broken up and mixed with topsoil prior to planting. In the rocky calcareous soils of Miami-Dade County, rock plowing to a depth of 6 to 8 inches (15 to 20 cm) and trenching about 16 to 24 inches (41 to 60 cm) wide and 18 to 24 inches (45 to 60 cm) deep is recommended.

The tree should be set at the same depth at which it was growing in the container. The new tree should be watered immediately after planting and frequently thereafter until it is well established. A mulch applied to the soil surface around the tree will help retain soil moisture and restrict weed growth. Commercially, the trees are planted at spacings of 18 to 30 feet (5.5 to 9.1 m) apart. In home gardens, they should be planted where they will receive full sun and not be crowded. At least 1 inch of water should be supplied weekly by rainfall or by irrigation, especially during the first year following transplanting..

ENVIRONMENTAL STRESSES

Drought: Coconut palms are tolerant of dry soil conditions. However, for optimum fruit production and quality, regular irrigation is recommended during dry periods.

Flooding: Coconut palms are tolerant of waterlogged or flooded soil conditions for a few days. However, trees may decline and die when exposed to prolonged flooding or waterlogged soils.

Cold temperatures: Coconut palms are injured by temperatures of 32 degrees F (0 degrees C), with desiccated foliage as the primary symptom. More severe freezes can also result in death of the bud. Coconut palms are not suitable for areas that regularly experience freezing temperatures.

Wind: Coconut palms are quite tolerant of windy sites and generally survive hurricane force winds. The most common damage from hurricane winds is loss of leaves and toppling over. If uprooted palms are righted promptly and adequately watered, survival of these palms is usually quite good.

Salt: Coconut palms are tolerant of saline water and soils, as well as salt spray.

Lightning: Lightning occasionally strikes tall coconut palms. Symptoms of lightning strikes include sudden collapse of the canopy, trunk splitting, and bleeding.

NUTRITIONAL PROBLEMS AND FERTILIZATION

Coconut palms in the landscape are susceptible to several nutritional deficiencies. Nitrogen (N) deficiency appears as a uniform yellowing of the oldest leaves