Transcript cotton - Bakersfield College

COTTON
Cotton Statistics
o Most important textile crop in world at over 70
million acres. Top acreages (2001 approx.):
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U.S. = 14 million
China = 9 million
India = 9 million
Pakistan = 3 million
o China top producer at 4 million metric tons
(18 million bales), U.S. close second at 3.8
million metric tons (17 million bales).
o Israel highest yields at over 1,800 lbs/acre
(3.75 bales/acre).
Cotton Statistics
o States with most acreage are (2001 approx.):
o Texas = 4.5 million
o Mississippi, Georgia = 1.5 million
o North Carolina,California, Louisiana = 1 million
o California has highest yields at 1,400 lbs/acre
(2.9 bales/acre).
o Texas has highest gross income at $975
million, California second at $733 million.
o Third highest grossing income crop in Kern
County at $226 million, behind grapes and
citrus.
Cotton Economics
o Cotton prices have declined dramatically over
the years.
o Some causes:
o Overseas competition
o Worldwide overproduction
o Use of synthetics and synthetic mixtures in textiles
History
o Evolved in Eurasia
o Many species, only four cultivated:
o Asian
o African
o Central American
o South American
o Cotton boll fragments from Central Mexico
found to be 7,000 years old.
o Cotton fabric made in India and Pakistan
5,000 years ago, and in Peru 4,500 years ago.
o Cotton grown as a perennial shrub or tree, with
each family owning a few “trees”.
o Columbus believed he landed in India partly
because he found cotton being cultivated.
Ancient Cotton Blanket
(Vietnam)
History
o American Indians observed raising cotton in Arizona
and New Mexico in 1500s.
o Commercial production began in U.S. when power
looms for fast spinning developed in England in
1700s.
o Eli Whitney invented the cotton gin to quickly
separate seed from cotton in 1793. Allowed for global
mass production of cotton.
o Led to development of much larger slave trade in U.S. to
supply huge need of English textile industry.
o Before Civil War, total U.S. production was ~5 million
bales = greater value than all other crops combined =
2/3 of U.S. treasury funds.
Mississippi Cotton Plantation
History in California
o By 1917, various varieties introduced to
California, including Acala and Pima varieties.
o Acala from Acala, Mexico.
o Bill Camp established variety trials in Central
Valley in 1917 – 1918.
o Acala became the only “legal” varieties that
were accepted by gins by San Joaquin Cotton
Board.
o Now can grow any cotton that meets
standards, but Acala gets premium.
Types of Cotton
o Acala types – discovered in Acala, Mexico in
early 1900s when hunting for boll weevil resistant
varieties. Medium to high quality and thread length.
Good yield, especially in California.
o Pima types – Egyptian long staple.
Very high
quality and fine fiber. Lower yields in California.
o Upland types – relatively thick fiber, short
thread length. Grow fast in short season. Good to
high yields in California.
o Sea Island – highest quality of all types.
Not
much grown because of low yield, very long season.
Basic Cotton Morphology
o Belongs to Mallow Family.
o Mostly self-pollinated. Can be crossed.
o Perennial treated as an annual.
o Flowers form at leaf axils. Unopened flower
buds have a typical shape and are called
“squares”.
o After pollination, five parted flower gives rise
to seeds covered with “lint” fibers in five
bunches called “locks” in each “boll” or fruit.
Cotton Morphology
Cotton Morphology
Open Boll With 5 Locks
Developing Boll Inside Square
Cultural Practices
Ground Preparation
o Best grown in rotation after legume, but
may be after corn, grains, etc.
o Laser level for flood/furrow irrigation.
o Rip or chisel ground with hardpans.
o Plow (if needed)
o Harrow to smooth
o Furrow and pre-irrigate (if irrigated)
o Form beds (if bedded)
Planting
o Can not legally plant here until after March
10th for control of pink bollworm.
o Use row seeders that plant 10 or 12 rows at a
time here.
o Usually planted here on 30 – 40” beds at
spacing of 3 – 6” in the row and ¾ to 2” deep.
o Many times use a soil mulch on top and seed
planted into moisture of pre-irrigation = good
weed control.
o Dryland cotton planted in March through
April, planted thinner and do not always use
beds.
Six Row Cotton Planter
Fertilization
o In irrigated areas, growers add about
130, 60, and 20 lbs/acre of N, P2O5, and
K2O, respectively, per season.
o Nitrogen applied as a split application,
usually during first and last cultivation,
or at seeding and last cultivation.
o Phosphorus and potassium usually
applied as a band during seeding.
o In the dryland areas of Texas and
Oklahoma, only 50% of the cotton is
fertilized.
Irrigation
o Most irrigation here is row irrigation,
most in deserts is via sprinkler.
o Cotton needs a minimum of 20 to 42” of
water, depending on temperatures, for
commercial production.
o It is grown only under irrigation from the
middle of Texas westward.
o Needs frequent, light irrigations until
after bolls are set; every 8 to 16 days.
o Soil moisture content should not drop
below 50% of field capacity.
Irrigation in Texas
Pest Control
Weeds
o Common area troublesome weeds are
Morninglory, Nightshade, Nutsedges,
Johnsongrass.
o Most grasses and some annual
broadleaves controlled pre-plant with
Treflan, Prowl, Caparol.
o Post-emergent herbicides mostly
applied as basal directed sprays such
as Goal, Bladex, Carmex, Caparol.
Morningglory
Johnsongrass
Herbicide Resistant Cotton
o Several cotton varieties
have gene for herbicide
resistance, so can be
applied over the top.
o Examples are Roundup
Ready (RR) or Buctril
Resistant (BXN).
o Roundup for almost all
grasses and
broadleaves, Buctril for
many broadleaves.
Weeds
o Up to Laybye, most weed control still
done via cultivation.
o Four or five cultivations between April and
July here.
o Last cultivation (Laybye) in early July here.
o Many growers have hydraulic
automated cultivator guides that can
get within one inch of each side of the
cotton plants.
Cotton Cultivation
Insects and Mites
o Cotton has about 25 common Arthropod
pests in the U.S. alone.
o Probably the most serious in the U.S. as
a whole are the bollworms; Lygus in
California.
o Arthropod control is via IPM, with
emphasis still on chemicals, although
cultural control and biocontrol
programs have been very effective for
some pests.
o Important Arthropod pests include:
Bollworms
o Also called the Heliothine Complex, the most
destructive of Arthropods.
o Larvae (worms) chew holes into bolls and
squares and hollow out locks.
o Thick, green, rank cotton most susceptible.
Keep cotton at recommended density and
moisture content.
o For untreated fields, economic threshold is 20
bollworms per 100 plants in early August.
o Insecticides include Bt, Monitor, Lanate.
Bollworm Egg, Larvae, Moths
Lygus spp.
o Second most damaging in U.S., first in
California.
o Damage from squaring through boll set.
o Pierce and suck juice from squares, bolls,
apical meristems, etc.
o Cotton is secondary host, alfalfa much
preferred. If numbers high, do not cut all
alfalfa fields around cotton at same time.
o Lygus resistance to insecticides is building,
so treatment should be just as needed.
o Insecticides include Temik, Dimethoate,
Monitor, Capture, many others.
Lygus Bug Adult and Nymphs
Thrips
o Not important in California, but early
season thrips cause big losses in
Southeast.
o In fact, some are beneficial in California as
mite predators.
o Feed on leaves, buds, apical meristems,
and squares.
o Early season control in Southeast with
Orthene and Monitor.
Western Flower Thrip
Aphids
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Fifth most damaging pest of U.S. cotton.
Significant losses in California.
Aphids live on many different hosts.
Cotton aphid highly variable in appearance; small
yellow to large black.
o Cause cupped, crinkled leaves, honeydew with
associated mold on leaves and/or lint.
o Cultural controls include avoiding thick, rank cotton,
planting earlier varieties, planting smooth leaved
varieties.
o Chemical controls initiated at about 50 aphids per
mainstem node for one week; 10 or less after boll
opening.
o Lorsban, Temik, Lannate, Furadan.
Cotton Aphids, Crinkled Leaf,
and Boll Mold
Silverleaf Whitefly
o Big problem in Imperial Valley, increasing problem
here in Southern San Joaquin.
o Overwinter on cole crops, ornamentals, weeds.
o As temperatures warm during summer, more and
more generations are produced. By early
September, numbers can be very high.
o Most whiteflies found underneath leaves sucking out
plant juices.
o Control:
o Keep fields away from major host crops like Melons.
o Plant early season varieties, so dry down before numbers
increase.
o Use insect growth regulators and non-pyrethroids early in
the season.
o Pyrethroids, like Capture, only used later in season, after
bolls open.
Whitefly Adult and Immature Stages
Boll Weevil
o Was by far most damaging pest in East.
o Control program has cut damage to < 1% of U.S. crop.
o Not damaging where < 25” precipitation, like here.
o Females deposit eggs in squares and bolls. Larvae
hatch and destroy bolls and lint.
o U.S.D.A Boll Weevil Eradication Program:
o Cultural control includes: 1) mandatory plowdown dates to
inhibit weevil feeding for overwintering, and 2) planting of
trap crops of cotton on field margins 2 weeks earlier than
rest of field.
o Economic thresholds depend on % square damage and vary
from state to state.
o Chemical controls include organophosphates (Malathion)
and organochlorines. Resistance has developed to
organochlorines.
Boll Weevil Larva, Pupae, Adult
Spider Mites
o Group of arachnids that cause significant
damage in California.
o Cause leaves to turn yellow or red and drop.
o Water stressed plants most susceptible and
mites suppressed by sprinkler irrigation.
o Chemical control with miticides like Kelthane,
Comite, Zephyr.
o Resistance has developed in many cases.
o Specific chemical depends on species of mite and
stage of infestation.
Spider Mites, Colony, Damage
Diseases
o More than 20 diseases affect cotton in
the U.S., but only a few are of great
economic importance.
o Cotton Root Rot in Texas
o Seedling blights found everywhere:
o Pythium
o Rhizoctonia
o Thielaviopsis
o Wilts found everywhere:
o Verticillium
o Fusarium
Cotton Root Rot
o Caused by Phymatotrichum omnivorum.
o Mostly in Southwest with calcareous
soils, especially Texas.
o Fungus lives in soil on living or dead
roots of many taprooted crops.
o No genetic resistance.
o Control via 2 – 3 year rotations with
grasses and turning in large amounts of
organic matter.
Cotton or Texas Root Rot
Seedling Blights
o Cause black or brown watery lesions on roots
and stems of young seedlings that may girdle
stem or root.
o Some seedlings may outgrow infections,
many die causing thin stands.
o Cultural control includes: 1) keeping good soil
drainage, especially during cool spring
weather, and 2) using proper crop rotation to
reduce inoculums.
o Chemical controls include seed fungicide
treatments such as Apron, Baytan, Nu-flow.
Damping Off of Seedlings and Lesion
Cotton Wilts
o Main symptom is wilting caused by
clogged xylem (water uptake tissue).
Leaves turn yellow, mottle, and drop.
o Verticillium wilt by far the most
important here.
o Some varieties of cotton are resistant to
the two major wilts and are the major
source of control.
o Fungicides can work, but are not
economical.
Verticillium and Fusarium Wilts
Nematodes
o Only major nematode pest is Meloidogyne incognita;
one of the root rotting nematodes.
o Attack young tap and lateral roots causing root
galling and stunting of plant.
o Provide infection sites for root rotting fungi such as
Fusarium.
o Cultural control via crop rotation with a grass
species.
o Acala varieties are somewhat resistant and NemX is
one Acala variety with moderate resistance.
o Soil fumigants such as Vapam and Telone II are
registered in cotton, but have not been shown to be
economical.
Nematode Life Cycle and Galls
Growth Regulators
o Many chemicals that mimic natural plant hormones
can be used to curb excessive growth in cotton.
o “PIX” is the chemical used in California.
o Artificial drought stress was used in the past, but PIX
allows for same result without possible yield losses.
o Shortens cotton plant, lessens vegetative growth,
leads to earlier crop, can increase yields.
o Usually applied as a foliar spray before flowering,
sometimes as a repeated application.
Harvest
Timing of Crop Termination
o Crop maturity
calculated using several
methods:
o Percentage of open bolls
(traditional).
o When >=65% open.
o Percentage of mature
bolls.
o Ease of cutting bolls with
knife.
o Seed maturity.
o Number of nodes above
first cracked boll.
Preparation for Harvest
o Because of 100% machine harvest in the U.S., it is
necessary to completely remove or desiccate leaf
material prior to harvest.
o In areas of significant fall frosts, this occurs naturally.
o In most cotton producing areas, like here, this is
accomplished with chemical sprays, usually
combinations of the following:
o Defoliants – most commonly used. Cause leaves to abscise
and drop. Examples are Dropp, Prep, Harvade.
o Desiccants – cause rapid leaf drying and death, but leaves
remain on plant. Examples are Starfire, Acclerate, Bollseye.
o Boll openers – hasten boll cracking and opening. Examples
are ethephon or any paraquat material like Starfire.
Defoliating Cotton
Harvesting Cotton
(see “Harvest” lecture)
o From July 1st in S. Texas to September 15th in
Oklahoma. Mostly September and November here.
o Cotton “Spindle Pickers” – wrap cotton on thousands
of tiny spindles. Very thorough, cleaner lint, slower,
more machine costs and breakdowns. Mostly used
here and where high value cotton.
o Cotton “Strippers” – brushes just strip bolls from
plants. Faster, less machine costs and breakdowns.
Mostly used in Texas for lower value cotton.
Spindle Picker and Brush Stripper
Harvesting Cotton
o Machines blow cotton into holding bins.
o Bins are emptied into “module builders” at
edges of fields being harvested.
o Module builders compact cotton into about
20,000 pound bales (40 traditional bales).
o Modules are covered with tarps and left on
the edge of the field to be picked up by
module trucks and taken to the gin.
o Cotton lint and seed quality decrease with
storage time in modules. Moisture levels
need to be <13% to keep modules from
heating.
Module Builder and Modules
Ginning
o Modules are loaded on “module trucks”, that back
under bales, and taken to gins for seed removal and
cleaning.
o Gins have highly sophisticated machinery that cuts
cotton, removes seeds, and cleans out trash.
o Ginning quality greatly affects final fiber quality.
o The lint and the seed have value:
o Many times the cost of ginning is more than paid for simply
by the value of the seed.
o The seed is a high protein animal feed.
o In California 99% of cotton seed is sold to dairies for animal
feed.
Module LoadingTruck
Modern Gin