Starchy Roots

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Starchy Roots
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New test speeds search for resistant bananas
12 March 2004
In recent years, Panama disease has had a major
impact on banana yields in Africa, Asia and
Australia, and is expected to spread to Latin
America and the Caribbean. .The fungus that
causes the disease, known as Fusarium oxysporum,
establishes itself in the soil and is virtually
impossible to control with chemicals.The current
method of detecting which banana strains are
susceptible to the disease is time-consuming and
laborious. It involves infecting soil with the
fungus, waiting for the plant to grow, and then
cutting the plant at the base of the stem to
evaluate the extent of internal damage. . The
new test takes just a few days to get results,
and can be carried out on a single leaf. The
fungus is grown in the laboratory and applied to
tiny perforations in harvested banana leaves.
After 48 hours, lesions of around 18 mm in length
can be seen in the leaves of susceptible plants,
while leaves from resistant plants have much
smaller lesions of less than 7 mm. . Ninety nine
per cent of bananas found in Western supermarkets
belong to a single variety, Cavendish, a sterile
clone that is propagated by cuttings. The variety
was initially adopted in the 1960s, when Panama
disease forced banana growers around the world to
abandon previous varieties. But now Cavendish
bananas are being infected with a new virulent
strain of the fungus, called race 4, making it
essential that new resistant strains are
developed.
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BananaMusaceae

• Common Names Banana, Bananier Nain, Canbur,
  Curro, Plantain
• Origin Indo-Malaysian region reaching to
  northern Australia.
• Fruits (technically a berry) ovaries develop
  parthenocarpically (without pollination) into
  clusters of fruits, called hands.
• cultivated types are seedless with just vestiges
  of ovules visible as brown specks. Occasionally,
  cross-pollination with wild types will result in
  a number of seeds in a normally seedless variety.
  
• Propagated vegetatively, genetic uniformity

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Jerusalem artichoke

• sunchoke, Helianthus tuberosus
• Pilgrims named this staple with regard to the
  New Jerusalem they were carving out of the
  wilderness
• Italians added name of girasole (turning to the
  sun because flowering heads follow path of sun
  during course of day
• English corrupted girasole artichoke to Jeruselum
  artichoke
• 10 protein, 76 carbohydrate inulin, no oil, no
  starch
• Inulin is digested into fructose, which is 1.5 x
  sweeter than sucrose
• folk remedy of diabetes
• Eat fresh, cooked or pickled

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Hidden virtues of root vegetables

• celery root, parsnips and turnips
• sweetest after the first frost, when the starch
  is converted into sugar
• Always begin cooking in cold water

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Starch properties

• plant's energy storage molecule, is found in
  seeds and roots
• Polysaccharides long chains of sugar units
• Salivary enzymes begins the breakdown of starch
  in the mouth, giving a slightly sweet taste
• In traditional diets, provides 85 of the total
  carbohydrates consumed and sugars only 15
• In higher socioeconomic countries, provides only
  62 of the total carbohydrates consumed and
  sugars provide 38.

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Iodine test

• Starch grains have recognizable shapes and other
  distinguishing properties.
• iodine solution to find and examine starch grains

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Starch makes a stand

• USA Today.com 25 Feb 2004
• Potatoes, pasta, rice and bread-once the
  high-carb heroes of dieters and marathon runners
  are being snubbed by consumers caught up in the
  low-carbohydrate craze
• Potato 100 calories for 1 medium size, 45 RDA
  Vitamin C 21 Calcium
• good carbohydrates nutrient-rich complex ones,
  found in plant food such as fruits, vegetables,
  whole grains, beans
• bad carbohydrates highly processed refined
  foods
• most of the world bases their diets on
  carbohydrates, and they dont have the obesity
  rates we do because they eat less exercise more

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Modified stems and roots

• Stems
• Stolons or runners
• horizontal stems, long internodes, found above
  ground
• Rhizome
• Horizontal underground stems
• Bulb
• vertical underground stem food reserves in
  leaves
• Corm
• vertical underground stem store food reserved in
  stem
• Storage Roots
• Tuber
• enlarged storage tips of rhizome
• Tuberous root
• fleshy fibrous roots, enlarged with food reserves
• Taproot
• biennial plants

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Botany of desire

• By Michael Pollan
• 4 desires sweetness, beauty, intoxication,
  control
• history of people manipulating plants - or is it
  a history of plants manipulating people?
• Web sites
• http//www.mapinc.org/drugnews/v02/n2042/a07.html
• http//www.salmonriver.com/Books/desirebotany.html
  
• Jim Leher News Hour interview (8 min)
• http//www.pbs.org/newshour/conversation/jan-june0
  1/botany_06-29.html

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Johnny Appleseed

• The apples which populated America in the 1800's
  by virtue of " Johnny Appleseed" were not the
  luscious, shiny and red ones we see today in the
  supermarket.  They were small and green and
  sour.  John Chapman, who later became known as "
  Johnny Appleseed" was an eccentric who wore a
  burlap sack, and tin pot for a hat.  He was an
  eccentric, but a very smart eccentric. He
  managed to precede settlers moving west planting
  apple orchards along riverbanks one or two years
  in advance from Pennsylvania westward.  When
  settlers arrived, he sold them small apple trees
  for their farms and ranches, thus populating a
  great portion of North America.  The irony here,
  of course, is that those apples were too sour to
  eat--but that was not their intended use--green
  apples made great apple cider. This could be
  made into a mild alcoholic beverage in great
  demand for thirsty settlers.  During the early
  1900's the apple industry began to polish its
  image, fearful of the propaganda from the
  temperance movement.  "An Apple a day, keeps the
  doctor away." was developed just for that
  purpose.

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Beauty and Survival

• Let's move on to the tulip, a flower much prized
  by humans for primarily one desirable feature
  its beauty.  In fact, from the years 1634 to
  1637, it was the subject of a speculative frenzy
  in Holland that was almost disastrous to its
  economy. The decorative aspect of flowers has a
  very practical benefit humans were attracted to
  food plants that produce memorable flowers,
  allowing them to remember this site, and
  eventually to collect, plant, and harvest them. 
  So, in a sense, a flowers attractiveness is a
  survival mechanism--and in the case of the tulip,
  a highly successful one.

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Smoking Rope

• Marijuana, known by several names, including
  cannabis has been much desired because of its
  ability to intoxicate the user.  It was first no
  less a good source of fibrous material to produce
  rope but then some inquisitive experimenter
  discovered it had other interesting qualities.
  "When the natural history of cannabis is
  written, the American drug war will loom as one
  of its most important chapters, on a par with the
  introduction of cannabis to the Americas by
  African slaves say, or the ancient Scythians
  discovery that hemp could be smoked." The
  modern war on marijuana during the Carter
  Administration produced a reaction--a revolution
  in the culture of the plant which led to its
  development into a much more powerful version. 
  Today the plant is cultivated in closed rooms
  under bright lights with other special treatment
  which produces highly potent flower buds.  The
  author reports that today Class A marijuana goes
  for 500 an ounce, as opposed to 40 years ago
  when it had a street price it of 100 per kilo.
  Pollan also discusses the effects of marijuana
  intoxication, and whether it intoxication comes
  directly from the substance, or rather
  facilitates that capability already present in
  the brain.  More about that in another column.

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Fries with that?

• Finally, we come to the lowly potato, and an
  interesting discussion about genetic modification
  ( GM ) of food.  McDonald's food chain is the
  largest purchaser of potatoes in the world.  And
  McDonald's only buys the best, to produce those
  very attractive fries that look like a bundle of
  yellow flowers in a bouquet. But producing such
  a potato is difficult and using conventional
  wisdom requires spraying potato fields with some
  of the most toxic chemicals now in use. One of
  those chemicals, called "Monitor" is a deadly
  chemical, known to damage the human nervous
  system.  "I won't go into a field for five days
  after it's been sprayed--not even to fix a broken
  pivot." said one grower.  Conversely, an organic
  farmer said he could eat any potato in his field
  "right now". Consequently producing the perfect
  potato for sale to McDonald's and other large
  industry is a prime mover behind GM.  For
  example the Monsanto Corporation has produced a
  potato, the "NewLeaf" which contains a gene and
  that makes the potato poisonous to its
  traditional enemy and pest the Colorado potato
  beetle.

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Is a newLeaf potato food or a pesticide?

• So, GM may reduce the need for some poisonous
  chemicals.  But fooling "Mother Nature" usually
  has its reaction--development of counter
  measures--and Monsanto admits that this product
  may only be good for 20 years or so. What is
  even more interesting--if not outright disturbing
  is the fact that these GM plants are not studied
  or tested by the FDA for their effects on
  humans.  Why" Because the FDA does not consider
  them "food" but a pesticide, and therefore under
  the jurisdiction of the EPA. The EPA says that
  since the pesticide (Bt) has always been safe,
  and the potato is a safe food, "you've got
  something that should be safe both to eat and to
  kill bugs with."

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Solanaceae(Nightshade or Potato family)

• simple, alternate leaves,
• flowers 5-merous and actinomorphic
• sepals and petals fused into a tube
• Fruit a berry or capsule
• 85 genera, 2800 species
• Includes tomato, potato, tobacco, eggplant,
  peppers, petunia

http//www.csdl.tamu.edu/FLORA/328Fall98/Solcopy/S
ol.html
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Market in Peru farmers in the Andes cultivate up
to 3,000 potato varieties.
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eye of the potato

• Buds located at the nodes
• Each bud can give rise to a new plant
• Sweet potato
• slips are adventitious shoots

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The Potato
Im just a dacent boy just landed from Ballyfad I
want a situation yes, I want it mighty bad I
seen employment advertised Tis just the thing
says I, But the dirty spalpeen ended with No
Irish need apply. American Balled of 1855
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POTATO

• scarcely innocent underground stem of one of a
  tribe set aside for evil
• could be used for exciting Venus
• could cause leprosy
• the English or Irish potato increaseth thy seed
  and provoketh lust in both sexes

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Potatoes are for peasants

• wanted peasants to eat potatoes and save wheat
  for nobility
• No tools are needed to cultivate
• Matures in 4 months
• High production
• Easy to prepare (just boil)

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Late blight in potato

• Introduced into Europe (Isle of Wight) in 1845
  from Americas
• Quick dispersal in the British islands and the
  continent in Ireland, major epidemics in
  1845-46 island-wide potato failure
• Control measures known at that time plant only
  every 6th year, use clean seed tubers not
  connected to diseased field do not feed diseased
  tubers to stock w/o boiling
• Ireland agricultural colony of Great Britain
• absentee (foreign) landlords - Irish serfs
• potato major staple wheat export crop
• no major industries elimination of competition
  with GB high unemployment
• 9 million people before epidemic 1 million
  deaths starvation, diseases (cholera, typhus,
  etc.)
• 1.5 million emigrants after epidemic 5.5 million
  emigrants until WWI, many to U.S. East Coast
  (Boston!)

The Potato A cautionary tale
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Pathogen

• DeBary disproves spontaneous generation
• Demonstrates blight caused by biological origin
• Phytophthora infestans
• Phyto plant
• Phthora devourer

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Sweet potato

• Species Ipomoea batatas (L.) Lam.Family
  Convolvulaceae
• Tropical perennial cultivated as an annual in
  temperate climates
• Enlarged edible storage roots
• 80 world production in China, US accounts for
  1 production
• Two types
• White to cream colored flesh, bland, non-sweet
  flavor, dry texture
• Yellow or deep orange, moist texture, distinct
  flavor, high sugar content
• http//www.hort.purdue.edu/newcrop/cropfactsheets/
  sweetpotato.html

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Sweet potato storage

• cure (30-35C, 90RH)
• Promotes wound healing provides a barrier to
  prevent bacteria and fungi from entering wounds
  received during harvest and handling
• stored (10-15C 85-90RH)
• Properly cured roots will store for 12 months or
  longer with 15-25 losses under the best
  conditions.

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Health benefits of yams

• Tubers contain saponins, type of steroid
• Used to make human sex hormones and cortisone
• progesterone

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Taro

• potato of the humid tropics
• Poi, traditional dish of native Hawaiians
• 1-2 m leaves
• Corms are steamed, crushed, made into a dough,
  and allowed to ferment naturally by microbes.
  Doughy paste eaten with fingers or rolled into
  small balls main staple in the traditional diet.
  
• Can be cooked similar to potatoes (baked,
  steamed, roasted, boiled) or processed into
  flour, chips, breakfast foods

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Manioc legend

• Mandioca is the indian name for manioc. This
  indian name is derived from
• Mandi Mani, name of the white indian child
• oca aca, similar to a horn.
• http//www.sumauma.net/amazonian/legends/legends-m
  ani.html

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Manioc Euphorbiaceae Manihot esculenta

• starchy staple in Africa, S. America
• Other names cassava, yuca
• large herbaceous shrub up to 10 feet
• fleshy roots contain poisonous compounds
  (cyanogenic glycosides - compounds that liberate
  cyanide) that must be removed. 
• resulting flour, called farofa
• purified starch for thickening agent
• tapioca are gelatinized pellets
• Cassava cultivation
• http//www.bio.ilstu.edu/armstrong/syllabi/cassava
  /cassava.htm

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detoxification

• peeling and grating the flesh, which causes the
  enzymatic reaction to occur,
• squeeze the contents and get the maximum surface
  area exposed to enzymes and to squeeze out some
  of the toxic leachate.
• pulp standsovernight and the remaining toxins are
  removed by the heat of cooking the pulp or meal
  into cakes.
• Other methods
• Sometimes drying in the sun is enough to remove
  the cyanide gas, it will disperse into the air as
  the manioc dries in the heat.
• sweet manioc is less toxic can be merely boiled
  or baked but is more pest disease susceptible
  to more toxic varieties

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Lotus (Nelumbo nucifera in Asia, N. lutea in N.
America)Family Nymphaeaceae

• Water Lily family
• Lotus roots are good stir-fried or steamed but
  they can also be boiled, baked, or braised
• Chinese traditionally serve them candied as a New
  Year treat.
• Japanese like them fried in oil, then cooked in
  lemon water. In India, hot pickles are made with
  them
• leaves and the flowers are also used as food,
  seeds are peeled and eaten
• husk leaves are used as the basis of medicinal
  teas in China

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Arrow rootMaranta arundinacea Family Marantaceae

• Name Arawak also used arrowroot tubers to draw
  poison from wounds inflicted by poisoned arrows
• starchy product of a tropical tuber
• arrowroot starch you can find in health food
  stores may actually be almost anything from
  bananas, rice, potatoes, to starch from almost
  any tropical root
• Used for thickening sauces makes very delicate
  sauces, and that it thickens at a lower
  temperature than corn starch
• http//www.specialfoods.com/arrowroot.html