Tropical Horticulture: Overview

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Lecture 39Lecture 39OverviewOverview

Salubrious and balmy vs. Hot and steamy

There are dramatically apposing attitudes towards the tropics, both anti- and pro-tropic sentiments

Cruise ships, waving palms vs. Poisonous snakes & crocs

Tropical Horticulture: Overview

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Resorts & retirement havens vs. Slums & shacks

Birth of civilization vs. Uncivilized

Green and bountiful vs. Starvation & malnutrition

Tropical Horticulture: Overview

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Rich in flora vs. Monotonously green

Tea

Cacao

Coffee

Beverage Crops

Avocado

Date

Citrus Banana & Plantain

Papaya Pineapple

Fruits and Nuts

Tropical Horticulture: Overview

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Cassava

Taro Yam

Sweetpotato

Starchy Vegetables

CoconutRubber tree

Industrial Crops

Rice Sugarcane

Grasses

Tropical Horticulture: Overview

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Ginger

Nutmeg

Clove PepperVanilla

Cinnamon

Spices

Bougenvillia

Orchids

Philodendron

Plumeria Poinsettia

Streletzia

Ornamentals

Revolution is the movement of the earth in an elliptical orbit around the sun whose average distance is 93 million miles away. The time to travel 1 orbit = 1 year. During this time there are 365.25 rotations of the earth.

Theory of the Tropics

Celestial Mechanics

Tropical Horticulture: Overview

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ET, tundraEF, icecap

Warmest month below 10°C (50°F)

PolarE

Da, humid continental, warm summerDaw, with dry winterDaf, with no dry season

Db, humid continental, cool summerDc, Dd, subarctic

Coldest month below 0°C (32°F); warmest above 10°C (50°F)

Humid, severe-winter temperate

D

Cs, Mediterranean (dry-summer subtropical)Csa, hot-summer MediterraneanCsb, cool-summer Mediterranean

Ca, humid subtropical (warm summer)Caw, with dry winterCaf, with no dry season

Cb, Cc, marine west coast (cool summer)

Coldest month between 18°C (64.4°F) and 0°C (32°F)

Humid, mild-winter temperate

C

BS, steppeBSh, tropical and subtropical steppeBSk, middle latitude steppe

BW, desertBWh, tropical and subtropical desert

Evaporation exceeds precipitation

DryB

Af, tropical rainforestAm, monsoon rainforestAw, tropical savannah

Coolest month above 18°C (64.4°F)

Tropical rainyASubclimates (incomplete)Chief characteristicMajor climateSymbol

Forests are stratified, typically 3 layers or strata

Tropical Horticulture: Overview

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Clays are the “life blood” of the soil due to the active exchange mechanism of bases.

Clays differ in tropics and temperate climatesTemperate clays: Montmorillonite (2:1 layer)Tropical clays: Kaolinite (1:1 layer)

Clays

Nutrient Recycling

Tropical Horticulture: Overview

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1521331361091004 months(May–Aug)

1011231271061008 months(March–Oct)

6891117105100Entire Year

D(Severe winter)

Ca(Mild

temperate)Cs

(Medit)AwAfTime

Net Photosynthesis as a Percent of Af Climate

Agriculture in Tropical Systems

Upland rice clearing in forest for rice, Maranhao

Tropical Horticulture: Overview

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Cerrado Burning, Brazil

Themes in Tropical Agriculture

Demographic Transition

Tropical Horticulture: Overview

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Norman E. Borlaug, 1970 recipient of theNobel Prize for Peace, working with hybrid

wheats at the CIMMYT Toluca station, Mexico

Lodging susceptible and resistant rice

Coffee Cherry

Tropical Horticulture: Overview

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Cacao,Orthotropic Tree

Cacao,Plagiotropic

Tree

Cacao fruit and dry beans

Tropical Horticulture: Overview

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Through fermentation and drying, the cacao

pod’s pulp-surrounded seeds are converted into nibs ready for

roasting and grinding into chocolate liquor

Rice paddy near Bandung, West Java, Indonesia

Sugar Mill, Ponte Nova, Brazil, 1963

Tropical Horticulture: Overview

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Tapping Rubber Trees

Originated in west and central Africa

TreeAn unbranchedmoneocious palm; 40–50 leaves (24/year), 10–11m at 25 to 35 years.

FruitA drupe with fleshy mesocarp and hard endocarp which surround 1, usually 2, and occasionally 3 seeds.

Oil palm, Elaeis guineensis

Cassava

Tropical Horticulture: Overview

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Edible Aroids

Banana

Pineapple

Tropical Horticulture: Overview

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I II III IV V

The flower type shows a relationship to fruit shape.

Papaya Flower Type

Valencia Orange, Israel

Nucellar polyembryony in Citrus

Tropical Horticulture: Overview

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Avocado varieties, Israel

Bird of Paradise

Anthurium, Hawaii

Tropical Horticulture: Overview

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Elephant pod

Double Poinsettia