APPLE PRODUCTION:
Apples come in all shades of red, green and yellow.
There are 7,500 varieties, or cultivars, of apples grown throughout the world.
There are 2,500 varieties of apples grown in the United States.
Apples are grown in all 50 states.
The world's top apple producers are China, the United States, Turkey, Poland and Italy.
In 2006-2007, commercial world production of apples was at 44,119,244 metric tons.
In 2006-2007, China led the world in commercial apple production with 24,480,000 metric tons, followed by the United States with 4,460,544 metric tons.
Total apple production in the United States in 2005 was 234.9 million cartons, valued at $1.9 billion.
In 2006, 58 percent of the apples produced in the United States were grown in Washington state, 11 percent in New York, 8 percent in Michigan, 5 percent in Pennsylvania, 4 percent in California and 2 percent in Virginia.
In 2005, 35.7 million bushels of fresh market apples were exported from the United States. That was 24 percent of the total U.S. fresh-market crop that year.
The Red Delicious variety is the most widely grown apple in the United States, with 62 million bushels harvested in 2005.
Commercial grade wax is applied to many apples after they are harvested and cleaned. These waxes are made from natural ingredients.
APPLE HEALTH BENEFITS :-
Apples are loaded with vitamin C. Almost half of an apple's vitamin C content is just under the skin, so it's a good idea to eat apples with their skins. Flores said that this is also where apples' fiber is found. Apples contain insoluble fiber, which provides bulk in the intestinal tract. The bulk holds water that cleanses and moves food quickly through the digestive system.
According to Flores, "Regular intake of apples has been shown to have cardiovascular benefits. [This is due to] two properties of apples: the fiber that they contain and the polyphenols that are found in high amounts."
In addition to digestion-aiding insoluble fiber, apples have soluble fiber, such as pectin. This nutrient helps prevent cholesterol from building up in the lining of blood vessels, which in turn helps prevent atherosclerosis and heart disease. In a 2011 study, women who ate 75 grams of dried apples every day for six months had a 23 percent decrease in bad LDL cholesterol, said study researcher Bahram H. Arjmandi, professor at and chair of the department of nutrition at Florida State University. Additionally, the women's levels of good HDL cholesterol increased by about 4 percent, according to the study.
When it comes to polyphenols and antioxidants, Flores explained that they "work in the cell lining to decrease oxidation resulting in lowering risk of cardiovascular disease."
Another study tracked food consumption among 9,208 people for 28 years. Those who ate more apples had a lower risk of stroke. Researchers attributed the results to quercetin, an antioxidant in apples.
There are respiratory benefits to eating apples, as well. "Apples' antioxidant benefits can help lower the risk of asthma,” Flores told Live Science. Also, a study of 2,500 middle-aged men in Wales found improved lung function among those who ate an apple a day, according to the University of California, Davis. A study in Brazil showed that adding three apples a day to women's diets helped lower their calorie intake and contributed to weight reduction.
APPLE AND CANCER
The American Institute for Cancer Research recommends eating lots of fruits and vegetables, including apples. The antioxidant content of apples ranks among the highest for fruits, and research shows that antioxidants help prevent cancer.
Lung cancer risk can especially be lowered through apples' antioxidants, according to Flores. A study in Hawaii found that people who regularly eat apples, onions and white grapefruit cut their lung cancer risk in half.
HEALTH RISK
"Eating apples in excess will not cause many side effects," said Flores. "But as with anything eaten in excess, apples may contribute to weight gain."
Furthermore, apples are acidic, and the juice may damage tooth enamel. A study published in 2011 in the Journal of Dentistry found that eating apples might be up to four times more damaging to teeth than carbonated drinks.
However, according to the lead researcher, Professor David Bartlett, head of prosthodontics at the Dental Institute at King's College in London, "It is not only about what we eat, but how we eat it." Many people eat apples slowly, which increases the likelihood that acids will damage tooth enamel.
"Snacking on acidic foods throughout the day is the most damaging, while eating them at meal times is much safer," Bartlett said in a press release from King's College. "An apple a day is good, but taking all day to eat the apple can damage teeth."
Dentists recommend cutting up apples and chewing them with the back teeth. They also recommend rinsing the mouth with water to help wash away the acid and sugars.
APPLES AND PESTICIDES
"Most apples will have pesticides on them, unless they are certified organic," Flores said. Results analyzed by the Environmental Working Group showed that 98 percent of conventional apples had pesticide residue on their peels. The group also said in its report, however, that "the health benefits of a diet rich in fruits and vegetables outweigh the risks of pesticide exposure." [Infographic: Guide to Pesticides in Produce]
Washing apples well helps remove pesticides, according to the Colorado State University Extension Service. "It's fairly easy… Washing apples and making sure you rub the skin in some way will do the trick," Flores said. "You can do this with your hands or a fruit scrubber." However, using chemical rinses and other treatments for washing fresh produce is not recommended because the Food and Drug Administration has not evaluated then for safety or effectiveness.
Some researchers say not to worry about pesticides. Dr. Dianne Hyson, a research dietitian at the University of California, Davis, writes that laboratory tests have shown very low levels of pesticide residue on apple skins.
ARE APPLE SEEDS POISONOUS?
Apple seeds, also called pips, contain a substance called amygdalin, which can release cyanide, a powerful poison, when it comes into contact with digestive enzymes. Whole seeds will pass through your digestive system relatively untouched, but if you chew the seeds you may be exposed to the toxins. One or two will not be harmful, as the body can handle small doses of cyanide, but if you or a child chews and swallows a lot of seeds, you should seek medical attention immediately. A very large helping of apple seeds may be fatal.
How many seeds are harmful? According to John Fry, a consultant in food science, about 1 milligram of cyanide per kilogram of body weight will kill an adult person. Apples seeds contain about 700 mg of cyanide per kilogram; so about 100 grams of apple seeds would be enough to kill a 70-kg (154-pound) adult. However, a seed weighs 0.7 grams, so you would have to munch on 143 seeds to get that amount of cyanide. Apples typically have about eight pips, so you'd have to eat the seeds of 18 apples in one sitting to get a fatal dose.
COMMON PEST AND DISEASE
Apple scab (Venturia insequalis):-
SYMPTOMS
Yellow or chlorotic spots on leaves; dark olive green spots on leaves and fruit; may be a velvety growth on spots on undersides of leaves; twisting of leaves; distorted leaves; severely infected leaves turn yellow and drop from tree
CAUSE
Fungus
COMMENT
Fungus overwinters on dead foliage on ground; spores dispersed by wind; high moisture encourages fungal growth
MANAGEMENT
Remove all leaves dropped from tree in the fall and compost to prevent any diseases surviving in debris; application of zinc and fertilizer grade urea in the Fall may be necessary to speed leaf drop, lime should then be added to fallen leaves; fungicide application may be necessary in areas where leaves remain wet for periods in excess of 9 hours; fungicides such as copper soaps and Bordeaux mixture should be applied if there is a chance of wet period as soon as leaf tips emerge.
Powdery mildew (Podosphaera leucotricha):-
SYMPTOMS
White velvety patches on underside of leaves; chlorotic spots on top side of the leaves
CAUSE
Fungus
COMMENTS
Fungal spores overwinter in buds; spread by wind
MANAGEMENT
Prune out infected shoots while dormant in early spring; apply sprays at pink bud stage to reduce build up; organic treatments include application of lime and sulfur.
Black rot (Botryospaeria obtusa) :-
SYMPTOMS
Purple flecks or circular lesions which are brown in the centre and purple at margin; red flecks, purple lesions and/or brown black rings on fruit
CAUSE
Fungus
COMMENTS
Spores can overwinter in twigs or fruit remaining on the tree and spread during rainfall
MANAGEMENT
Remove dead wood, mummified fruit and cankers from trees to reduce spread of disease; burn any prunings that have been made from the tree; disease can be controlled by applying fungicides from silver tip to harvest.
Sooty blotch and flyspeck :-
SYMPTOMS
Sooty blotches with an indefinite margin on surface of fruit; blotches may coalesce to cover entire fruit; shiny black fungal fruiting bodies appear as dots arranged in irregular to circular pattern on fruit surface
CAUSE
Fungi
COMMENTS
Infections occur mainly during periods of high rainfall and high humidity
MANAGEMENTS
Plant trees in area with good sunlight and air circulation; prune trees to an open center; blemishes superficial and can be washed off.
Apple maggot (Rhagoletis pomonella) :-
SYMPTOMS
Misshapen, pitted and sunken areas on fruit surface; browning and rotting of apple flesh
CAUSE
Insect
COMMENTS
Surface damage caused to fruit by female laying her eggs; larvae damage flesh by burrowing and feeding
MANAGEMENTS
Use red spherical sticky traps to trap adults, place one trap for every 100 apple fruits; bag apples by tying or stapling polythene bags around fruit to prevent adults laying eggs - cut corners from bags to ensure air supply to fruit; spray fruit with insecticide prior to eggs being laid.
Codling moth (Cydia pomonella) :-
SYMPTOMS
Holes and burrows in fruit; holes may be blocked with crumbly brown frass (insect excrement); wounds may be shallow or may be deep burrows extending to the fruit’s core; adult insect is a dark brown moth; larvae are pink with a brown head and may be up to 1.3 cm (0.5 in) long
CAUSE
Insect
COMMENTS
Insect usually undergoes 2-4 generations per year
MANAGEMENT
Proper pruning methods help to open out tree canopy to ensure treatments penetrate interior of the tree and reach larvae; removal of any wild hosts or trees in abandoned orchards helps remove reservoirs of insect; organically acceptable control methods include application of Entrust and kaolin clay; small scale growers and home gardeners can remove infested fruit by hand before larvae leaves fruit to reduce insect population; successful reduction of insect population in large scale orchards is usually achieved by mating disruption by releasing pheromones over successive years.
PROPAGATION
Apple trees grow best in the tropics and at higher latitudes they require a mild growing season and a cold winter to break their dormancy. At these latitudes, the tree will flower in spring and fruit will ripen in the fall. In the tropics, the leaves will remain on the tree longer so that it is essentially evergreen and flowering and fruiting will happen sporadically throughout the year unless the tree is managed to enforce a uniform cycle across the entire tree by bending shoots to create a wide tree.
The standard method of propagating apple is by budding. When planting an apple nursery or orchard it is highly advisable to plant seedlings budded from root stock to prevent an increase in dormancy of the buds. Budded trees should be pruned in the first year to encourage new shoot growth.
In the tropics, apple trees require careful management in order to make the heavy crop loads sustainable. This includes bending shoots, pruning the tips and also defoliating the trees. Flowers are also removed to promote growth until the first fruit production, generally after 2 years.
Apple trees can also be propagated by grafting and mound layering. Grafting involves joining the lower part of one plant (root stock) with the upper part (scion) of another. Grafting is usually done during the dormant season and must be done on dormant scion and stock wood. Mound layering is used to propagate apple clonal root stocks. Soil is mounded around shoots that have been cut back, thereby stimulating roots to grow at the base of the shoots. A year before propagation begins, 8–10 mm (0.3–0.4 in) diameter stock plants are planted in rows and then cut back to 45–60 cm (17.7–23.6 in). They are then grown for one year. In the spring, the plants are again cut back, this time to 2.5 cm (1 in) above the ground. New shoots gradually form and more soil and bark are added in mounds around the plants. This cycle can continue on through the growing season. Then the shoots are harvested by cutting close to the bases. The mother stool beds are then left exposed until further growth of the new shoots has occurred, and another cycle of hilling begins.
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