Panruti Cashews: ♥ General Information..!!

Anacardium occidentale

FAMILY : Anacardiaceae
LATIN NAME : Anacardium occidentale L.
SYNONYM(S) :
ENGLISH : Cashew, Cashew nut
FRENCH : Pomme d'Acajou, Pommier Cajou, Acajou à Pomme, Anacardier

DESCRIPTION:
Particularities for easier identification: It is most easily recognised by its obovate coriaceous leaves and also its fruits that consist of a kidney shaped nut attached to a swollen pedicel (cashew apple).Cashew nuts are the true fruit, while the cashew apple, about eight to ten times as heavy as the nut, is the swollen stalk, or peduncle, which supports the flower. The nut shell is smooth, oily and about one-eighth of an inch thick. Its honeycombed, cellular, inner portion contains the cashew nut. The cashew nut kernel is approximately seven-eighths of an inch in length, and is wrapped in a testa or thin brown skin. This is the cashew nut of commerce. The nut shell with its side indentation pointed upward, looks like a heart. The generic name Anacardium means “shaped like a heart.” Cashew trees start bearing fruit usually in the third or fourth year and under favorable conditions reach maximum production in about seven years. Although yields vary considerably, a fair, average annual yield from a mature cashew tree is about one hundred to one hundred-fifty pounds of apples and nuts from which twenty pounds of un-hulled nuts and six pounds of kernels can be obtained. Cashew nuts have been called the poor man’s crop but a rich man’s food. The World Bank has estimated that at least 97% of world cashew production comes from wild growth and small peasant holdings.Cashews are more widely used in confectionery nut candies and chocolate bars than in bakery products. Cashews have become one of the most popular dessert nuts behind almonds. They are delicious in their natural state, or in a variety of candied varieties including chocolate covered and honey roasted cashews. Approximately 60% of cashew kernels are consumed as salted nuts.

Habit: A medium sized evergreen tree that can reach up to 12m in height with a diameter to 25cm.

Bark & Branches: It has a short stout bole surmounted by a rounded trunk that is characteristically grey and smooth or lightly fissured, slash pale red and exuding a brown coconut scented resinous gum. The branches are heavy and crooked; twigs are greyish stout and glabrous.

Leaves: are alternate, petiolate (1-2cm), simple, obovate, 6-20cm long by 4-15cm wide, have a recurved margin and are often crowed towards the ends of the branches. They are coriaceous, glabrous and bear prominent abaxial veins.

Inflorescences: arise as terminal panicles of about 5-20cm with large bracts enclosing the many flowers.

Flowers: are (male or hermaphrodite), small (5-10mm), star shaped and sweetly scented. They consist of a 5 lobed greenishwhite corolla; 5 (6) linear-lanceolate, red striped, petals, a long protruding stigma and 7-10 stamens shorter then the flower cup.
Fruits: are greyish-brown and approx. 3cm long, they consist of kidney shaped nuts (the cashew nut) which are encased in a hard shell (pericarp). The nut is attached to a swollen pedicel (cashew apple when ripe). The “Cashew Apple” is shaped slightly like a doum palm nut (Hypheane thebaica), measures 10-20cm long by 4-8cm wide, and is shiny red or yellow with a characteristic smell. Flowers November to May; fruits February to April.

DISTRIBUTION:
Originates from the American tropics but has been widely spread throughout the tropics since the 16th century. It has become naturalised in numerous parts of Africa and is particularly common in coastal regions.

TREE REQUIREMENTS:
Rainfall : 500-4,000mm; 900+mm for good results; tolerates and requires a 4-6 month dry season for good fruiting.
Soil Type : Tolerates a wide variety of soils, except saline soils and indurated soil horizons. Prefers sandy soils with good drainage. Its resistance to drought is directly in proportion to the amount of soil available to the roots.
Altitude : 0 - 1,100 metres; best adapted to lower elevations (0-500m).
Temperature : Reported mean min. and max . monthly temperatures are as follows: 19 and 35° C. Tolerates high temperatures; frost sensitive.
Propagation : 150-300 seeds/kg. The seed is only viable for about a month. Seedlings can be grown in the nursery but are most commonly planted on site since this tree produces a taproot and is susceptible to root damage. Seeds do not need pretreatment but germination is rather poor and slow (starts after about 10 days). Seeds can be planted with or without the shell but taking the shell off requires great care and experience in avoiding the blistering juices. If shells have been removed then the nuts can be put in water and planted if they sink. Usually 3 seeds are planted (convex side up) per hole and this is later thinned out to 1 plant. Daily watering is required until established after about 6 months. After that watering can be reduced gradually. If planting in the nursery then long polythene pots are recommended. This tree can also be propagated vegetatively if certain characteristics are desired; however, further information should be sought on how to do this.

Possible options are:-
Grafting: Taking a bud or shoot from a good tree and grafting it onto a seedling.
Air layering: Make a ring cut in a pencil thickness branch towards the end. In this cut place a mixture of sawdust and woodshaving and keep it moist and covered with plastic for 1½ months. Roots should have formed by then. The roots should continue to be kept wet and the branch should be cut halfway through below the plastic. This cut should be slowly deepened until after another 1½ months the rooted tree can be planted out.
After Care : Once the tree is established then little care is required. When young, it needs weeding and some pruning to give it a good shape. When planted, spacing should between 10 and 15 metres apart. Fruit production starts after about 4 years reaching a maximum after 10 years: a maximum of 5-8kg of nuts and 50-60kg of apples can be expected per year.Pollination of the flowers is usually carried out by insects but in India this is sometimes done by hand. If a lot of fruit falls off after flowering then there is no need to be alarmed as this early fruit fall is quite normal with this species.

Uses:

Many parts of the cashew plant are used. The cashew "apple," the enlarged fully ripe, fruit may be eaten raw, or preserved as jam or sweetmeat. The juice is made into a beverage (Brazil cajuado) or fermented into a wine. Fruits or seeds of the cashew are consumed whole, roasted, shelled and salted, in Madeira wine, or mixed in chocolates. Shelling the roasted fruits yields the cashew nut of commerce. Seeds yield about 45% of a pale yellow, bland, edible oil, resembling almond oil. From the shells or hulls is extracted a black, acrid, powerful vesicant oil, used as a preservative and water-proofing agent in insulating varnishes, in manufacture of typewriter rolls, in oil- and acid-proof cements and tiles, in brake-linings, as an excellent lubricant in magneto armatures in airplanes, and for termite proofing timbers. Timber is used in furniture making, boat building, packing cases and in the production of charcoal. Bark used in tanning. Stems exude a clear gum, Cashawa gum, used in pharmaceuticals and as substitute for gum arabic. Juice turns black on exposure to air and provides an indelible ink. Along the coast of Orissa, shelter belts and wind breaks, planted to stabilize sand dunes and protect the adjacent fertile agricultural land from drifting sand, have yielded economic cashew crops 5 years after planting (Patro and Behera, 1979).
Folk MedicineThe fruit bark juice and the nut oil are both said to be folk remedies for calluses, corns, and warts, cancerous ulcers, and even elephantiasis. Anacardol and anacardic acid have shown some activity against Walker carcinosarcoma 256. Decoction of the astringent bark given for severe diarrhea and thrush. Old leaves are applied to skin afflictions and burns (tannin applied to burns is liepatocarcinogenic). Oily substance from pericarp used for cracks on the feet. Cuna Indians used the bark in herb teas for asthma, colds,and congestion. The seed oil is believed to be alexeritic and amebicidal; used to treat gingivitis, malaria, and syphilitic ulcers. Ayurvedic medicin recommends the fruit for anthelmintic, aphrodisiac, ascites, dysentery, fever, inappetence, leucoderma, piles, tumors, and obstinate ulcers. In the Gold Coast, the bark and leaves are used for sore gums and toothache. Juice of the fruit is used for hemoptysis. Sap discutient, fungicidal, repellent. Leaf decoction gargled for sore throat. Cubans use the resin for cold treatments. The plant exhibits hypoglycemic acitivity. In Malaya, the bark decoction is used for diarrhea. In Indonesia, older leaves are poulticed onto burns and skin diseases. Juice from the apple is used to treat quinsy in Indonesia, dysentery in the Philippines.

Toxicity:

He who cuts the wood or eats cashew nuts or stirs his drink with a cashew swizzle stick is possibly subject to a dermatitis.

Chemistry:

Per 100 g, the mature seed is reported to contain 542 calories, 7.6 g H2O, 17.4 g protein, 43.4 g fat, 29.2 g total carbohydrate, 1.4 g fiber, 2.4 g ash, 76 mg Ca, 578 mg P, 18.0 mg Fe, 0.65 mg thiamine, 0.25 mg riboflavin, 1.6 mg niacin, and 7 mg ascorbic acid. Per 100 g, the mature seed is reported to contain 561 calories, 5.2 g H2O, 17.2 g protein, 45.7 g fat, 29.3 g total carbohydrate, 1.4 g fiber, 2.6 g ash, 38 mg Ca, 373 mg P, 3.8 mg Fe, 15 mg Na, 464 mg K, 60 mg b-carotene equivalent, 0.43 mg thiamine, 0.25 mg riboflavin, and 1.8 mg niacin. Per 100 g, the mature seed is reported to contain 533 calories, 2.7 g H2O, 15.2 g protein, 37.0 g fat, 42.0 g total carbohydrate, 1.4 g fiber, 3.1 g ash, 24 mg Ca, 580 mg P, 1.8 mg Fe, 0.85 mg thiamine, 0.32 mg riboflavin, and 2.1 mg niacin. The apple contains 87.9% water, 0.2% protein, 0.1% fat, 11.6% carbohydrate, 0.2% ash, 0.01% Ca, 0.01% P, .002% Fe, 0.26% vitamin C, and 0.09% carotene. The testa contains a-catechin, b-sitosterol, and 1-epicatechin; also proanthocyanadine leucocyanadine, and leucopelargodonidine. The dark color of the nut is due to an iron-polyphenol complex. The shell oil contains about 90% anacardic acid (C22H32O3 and 10% cardol (C32H27O4). It yields glycerides, linoleic, palmitic, stearic, and lignoceric acids, and sitosterol. Examining 24 different cashews, Murthy and Yadava (1972) reported that the oil content of the shell ranged from 16.6 to 32.9%, of the kernel from 34.5 to 46.8%. Reducing sugars ranged from 0.9 to 3.2%, non-reducing sugars, 1.3 to 5.8%, total sugars from 2.4 to 8.7%, starch from 4.7 to 11.2%. Gum exudates contain arabinose, galactose, rhamnose, and xylose.

Germplasm:

Several varieties have been selected based on yield and nut size. Reported from the South America, and Middle America Centers of Diversity, cashew or cvs thereof is reported to tolerate aluminum, drought, fire, insects, laterite, low pH, poor soil, sand, shade, slope, and savanna. (2n = 42, 40)

Distribution:

Native to tropical America, from Mexico and West Indies to Brazil and Peru. The cashew tree is pantropical, especially in coastal areas.

Ecology:

Ranging from Warm Temperate Moist to Tropical Very Dry to Wet Forest Life Zones, cashew is reported to tolerate annual precipitation of 7 to 42 dm (mean of 32 cases = 19.6), annual temperature of 21 to 28°C (mean of 31 cases 25.2), and pH of 4.3 to 8.7 (mean of 21 cases = 64). Grows on sterile, very shallow and impervious savanna soils, on which few other trees or crops will grow, but is less tolerant of saline soil than most coastal plants. Does not tolerate any frost. In Brazil, Johnson (1973) summarizes "optimal ecological conditions;" annual rainfall 7–20 dm, minimum temperature 17°C, maximum temperature 38°C; average annual temperature 24–28°C, relative humidity 65–80%; insolation 1,500 to 2,000 hours per year, wind velocity 2.25 km/hr, and dry season 2–5 months long. It is recommended that cultivation be limited to nearly level areas of red-yellow podzols, quartziferous sands, and red-yellow latosols.

Cultivation:

Cashew germinates slowly and poorly; several nuts are usually planted to the hole and thinned later. Propagation is generally by seeds, but may be vegetative from grafting, air-layering or inarching. Planting should be done in situ as cashew seedlings do not transplant easily. Recommended spacing is 10 x 10 m, thinned to 20 x 20 m after about 10 years, with maximum planting of 250 trees/ha. Once established, field needs little care. Intercropping may be done the first few years, with cotton, peanut, or yams. Fruits are produced after three years, during which lower branches and suckers are removed. Full production is attained by 10th year and continues to bear until about 30 years old. In dry areas, like Tanzania, flowering occurs in dry season, and fruits mature in 2–3 months. Flowers and fruits in various degrees of development are often present in same panicle.

Harvesting:

From flowering stage to ripe fruit requires about 3 months. Mature fruit falls to the ground where the 'apple' dries away. In wet weather, they are gathered each day and dried for 1–3 days. Mechanical means for shelling have been unsuccessful, so hand labor is required. Cashews are usually roasted in the shell (to make it brittle and oil less blistering), cracked, and nuts removed and vacuum packed. In India part of nuts are harvested from wild trees by people who augment their meager income from other crops grown on poor land. Kernels extracted by people skilled in breaking open the shells with wooden hammers without breaking the kernels. Nuts are separated from the fleshy pedicel and receptacle, seed coat removed by hand, and nuts dried. Fresh green nuts from Africa and the islands off southern India are shipped to precessing plants in Western India.
Yields and EconomicsYields are said to range from 0–48 kg/tree/year, with an average yield of 800–1,000 kg/ha. Heavy bearing trees often produce nuts considered too small for the trade. Indian field trials showed that fertilizers could increase yields of 15-year-old trees from less than 1 kg/tree to >4 and enabled 6 year olds to average 5.7. Regular applications of 250 g N, 150 g P2O5 and 150 g K2O/tree resulted in average yield increases of 700–1600 kg/ha (Nambiar and Haridasan, 1979). In Pernambuco, trees produced 1.5–24.0 kg each/year, averaging 10.3 kg per tree (Johnson, 1973). At Pacajus (Ceara, Brazil) trees average 17.4 kg/yr with one tree bearing 48 kg/yr. Major producers of cashew nuts are India, Tanzania, Mozambique, and Kenya. In 1968 India planted over 224,000 ha in cashews to supply over 200 processing factories operating all year. In 1971 India produced 90,000 MT, the bulk exported to United States and USSR. Export price at US ports was $.33/kg. India imports green nuts from the African countries and processes them for resale. Import prices in 1971 in India was 1730 rupees/MT. Cashawa Gum is obtained from the West Indies, Portuguese East Africa, Tanzania and Kenya.
EnergyA perennial species, the cashew has already, in the past, yielded alcohol from the "apple," oil from the nut, and charcoal from the wood. The "apples" (ca 30–35 kg per tree per annum) yield each 20–25 cc juice, which, rich in sugar, was once fermented in India for alcohol production.
Biotic FactorsCashew tree has few serious diseases or pests. The following are reported disease-causing agents, none of which are considered of economic importance: Aspergillus chevalieri, A. niger, Atelosaccharomyces moachoi, Balladynastrum anacardii, Botryodiplodia theobromae, Cassytha filiformis, Cephaleuros mycoides, Ceratocystis sp., Cercospora anacardii, Colletotrichum capsici, Cytonaema sp., Endomyces anacardii, Fusarium decemcellulare, Gloeosporium sp., Glomerella cingulata, Meliola anacardii, Nematospora corylii, Parasaccharomyces giganteus, Pestaliopsis disseminata, Phyllosticta anacardicola, P. mortoni, Phytophthora palmivora, Pythium spinosum, Schizotrichum indicum, Sclerotium rolfsii, Trichomerium psidii, Trichothecium roseum, Valsa eugeniae. Cuscuta chinensis attacks the tree. In Brazil, high populations of the nematodes Criconemoides, Scutellonema, and Xiphinema are reported around cashew roots (Lima et al, 1975). Of insects, Helopeltis spp. have been reported in Tanzania. Four insects are considered major pests: the white fly (Aleurodicus cocois), a caterpillar (Anthistarcha binoculares), a red beetle (Crimissa sp.), and a thripe (Selenothrips rubrocinctus). Flowers are visited by flies, ants and other insects, which may serve as pollinators. Artificial pollination is practiced in some areas.

OTHER POINTS:
A species that could be tried in lowland areas with a rainfall of more then 700mm. Production with lower rainfall might be possible with suitable water harvesting techniques. Although it grows well vegetatively, constant year round humidity impedes fruit production.

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