Cotton!AGRO 1033

HistoryCultivated for the past 6000+ years in Egypt, India, Asia and the Americas.Used primarily as a fiber crop.Very profitable crop in the early 1800s in the U.S. due to world demand.Almost devastated in the late 1800s by the boll weevil.A prestigious, expensive and difficult crop to grow.

BotanyWarm seasonPerennial (grown as an annual though)Woody shrubC3IndeterminateDicot with cotyledonary leavesMalvaceae family

Botany Two main groups. - Old World cotton - diploids (2n) - G. arboreum - G. herbaceum

- New World cotton - allo tetraploids (4n) - G. hirsutum - G. barbadense

Botany Six main cultivated types in U.S.1. Eastern - Bred for eastern U.S. (Carolinas, GA, FL)- Fusarium wilt resistant.2. Delta - MS alluvial areas- Heat, humidity tolerant.

Botany Six main cultivated types.3. Plains - Bred for SW plains, TX, OK, NM- Short, stocky, compact bolls.4. Acala - CA, AZ, NM arid regions, most irrigated. - High quality fiber

Botany Six main cultivated types.5. Pima - Separate class- Long growing season- Very high quality and long fiber6. Sea Island - G. barbadense species - High quality fiber - Long growing season

Cotton LintElongated epidermal cells off seed coat.Hollow, twisted.Cellulose.No artificial fiber like it.

The cotton plantSeedling

The cotton plantGeneral growth cycle

The cotton plantFlowering

The cotton plantFlowering

The cotton plantFruit (boll) development

Two types of cotton branches.MONOPODIUM.Vegetative 1st 4-6 nodesSYMPODIUM.Fruiting.Nodes 5-7+

The cotton plantBranches grow at 3/8 turn to give a twist shape. This is the phyllotaxy.

The cotton plantBeing an indeterminate, cotton growsBoth upward, and outward on fruitingBranches.

The cotton plantMapping cotton positionsPosition 10.2Main node 10Fruit position no. 2710123The cotyledon node is 0, the next main Branch node is 1 and so forth.Main nodeBranch nodeexample

The cotton plantThe nodes above white flower (NAWF) Decreases with maturity. This is usedTo monitor the crop growth and to Time late season management practices.

Cotton productionMid-April to mid-May30 38 in rowsAbout 44000 seeds/acreWell-drained loamy soil bestSeed fungicide treatments standardInsecticides, nematicides, and other fungicides sometimes added.planting

Cotton productionOptions:- conventional- Bt insect resistance transgenics (eg., BG, BGII). - Herbicide resistant transgenics (eg., RR).Look at University yield trials, company literature.Use good agronomic practices.Variety selection

Cotton productionCutworms- soil larvae- cut down seedlings- insecticides Thrips- very tiny insects- suck sap - control with in-furrow or foliar insecticides.Insect management early season

Cotton productionPlant bugs- three species- feed on squares- careful scouting- insecticides Insect management mid seasonTarnished CloudedCotton fleahopper

Cotton productionHeliothis larvae- two species - cotton bollworm - tobacco budworm- Bt transgenics (eg., BG, BGII)- insecticides Insect management late seasonCotton bollwormTobacco budworm

Cotton productionStinkbug- three species - green - brown - Southern- careful scouting- insecticides Insect management late seasonGreenBrownSouthern Green

Cotton productionOther insects: - spider mite - cotton aphid - whitefly - armyworm - looper

- careful scouting- insecticides Insect management late seasonSpider mitesCotton aphidswhitefliesFall armywormLooper

Where is the boll weevil?The state and regional Boll Weevil Eradication Programhas just about eliminated this problem. It is a grower/government financed program that involves aggressivemonitoring and spraying insecticides. However.

There are a few sub-species of this pestout there that are proving to be HIGHLYresistant to all control efforts. They are extremely ornery, tough and elusive. Ifyou see any, call the authorities!

Cotton ProductionSoil managementSoil test! Best pH 5.8 7.0P, K applied pre-plantN management:- rates vary by variety, soil, range 90-150 lbs N/acre- 50-60 lbs N/bale needed- apply N pre-plant, at first bloom

Cotton ProductionSoil managementExamples of tillage systems:Conventional, 38 in rows, raised beds.Flat planted.Narrow row = 30 in.No-till.Fallow seed bed planting.Cotton prefers a well-drained loamy soil.

Cotton: harvestingPre-harvest management DefoliationDefoliants are applied to cotton to improve harvest andfiber quality. Boll OpenersBoll openers are ethylenereleasing PGRs that allowmature bolls to open up, thereby improving harvestefficiency.

Cotton harvesting:Types of harvest equipment.6-row cotton pickerCotton stripperCotton module

Ginning cottonFrom Eli Whitneysgin to ..The modern high speed gin of today.

Fiber quality Color main one.Trash content.Fiber length. Measured in 32nds of an inch, eg., a 34 is 1 1/16 in.Length uniformity. Measured in %.

Fiber quality Micronaire. A measure of fiber fineness and maturity.

Premium range: 37-42 Base ranges: 35-36, 43-49

Fiber quality Fiber strength. Measured in g/texx.

Cotton classification 12 USDA classification offices in U.S.Every bale classed!HVI = High Volume Instrumentation.Two Classes:

American UplandPima

Cotton classification Example grades:

SLM White strict low middlingGM Lt Sp Light spotted good middlingSM TgTinged strictmiddling

About 25 grades in all.

Cotton mouth!Dont pick this one!

Cotton : from planting ..

to harvest - always a challenge!Any questions?