Lecture 26: Insects &

Agriculture

Where’s the problem??

Key Points: Insects & Agriculture: Where’s the problem?

• What are the limitations of the wheat, rice and corn paradigms• What is the function of the clonal repositories• How important are pest insects in world food

production• What are the attributes/problems of 1st world ag.?• How will the loss of pesticides affect our economy?

History of human development• Genus Homo - 1.5 to 2 million years B.P.• Homo sapiens - 200,000 years B.P.• Homo sapiens sapiens - 30 to 40,000 years

B.P.– This is “modern” man (human), dating from the

discovery of Cro-Magnon• For 99.5% of our existence as a species we

lived in a hunter/gatherer societal structure.

Most important change in cultural development

• What was it???• Development of AGRICULTURE

– H. Curtis (1983) BIOLOGY

Evolution of Agriculture• 12,000 BP to 18th Century

– Productivity was low but slow upward direction– Thomas Jefferson’s Agrarian Society ideal

• 18th Century to Today– Rapid increase in productivity– Many fewer persons involved in “production”

agriculture in 1st world societies.• 1.8% of U.S. citizens are “farmers”• Ca. 80% in Bangladesh• Worldwide it is ca. 50%

World Diet

• Twenty-Nine major food crops– The BIG Three

• WHEAT - RICE - CORN– plus 15 vegetable species– plus 15 fruit species

• World Diet is 94% plant product & 6% animal product.

World Diet

• Edible Plants– Estimated that there are 80,000 species from which

some edible portion is available– Of this huge assembly, only 50 are actively

cultivated

{germ plasm repositories}

Of this 50 species, only seven provide 75% of the world’s food supply

wheat - rice - corn - potatoes - barley - cassava & sorghum[SCIENCE vol. 257: 1347 (1992)]

The entrance to the underground Svalbard Global Seed Vault juts from a hillside in the Norwegian Arctic. (Credit: John McConnico/Associated Press)

National Clonal Germplasm Repository

• One of about 30 in the U.S.• Specializing in temperate fruit (pears),

nuts,

and Humulus.

World Food Production• Is it sufficient??• Population = 7 BILLION +

– 50% directly involved in food production.– Ca. 20 to 25% inadequately nourished– One-third of world mortality related to poor

nutrition– 40,000 children will die within the next 24

hours [1,666 in this hour]

Are there food production problems?• Not in developed nations

– the irony is too frequently an overproduction of given crops• the political mess of subsidies & production

control targets (economics)• Yes, in developing nations

– famine– political instability

• Paradox of resource utilization vs population (U.S. with 5% of pop. using 30% of world resources)

Famine• Primary Causes

–CLIMATE (weather)–SOIL FERTILITY (erosion)– pests

• Insects are direct competitors for our food• dead last but still accounts for 20% crop losses,

and that is with the use of insecticides

Constraints to agriculture growthBiological

• most important aspect • rice & corn paradigm

Technologicalcan we keep up?resistance to gains (GMOs)

Societaldemographic shift of rural to urbanized, literal loss of our agrarian “roots”we are not reminded on a daily basis of importance of continued investment in Agriculture

Population & the Environment

Natural resource base can optimally sustain 3 billion persons. [From David Pimentel, 1994], (Sustainable future World population hardcover, Amazon.com)

{Note: big debate on the issue of the sustainable human population of earth}

Land degradation will depress world food production 20% in the next 25 yr.

Fundamental attributes/problems of 1st World Agriculture

• Specialization– by individuals & corporations– mega-monocultural development

• Elevated Energy/Production Inputs– fertilizers (Oregon: 1 billion lbs./yr.)

• works out to 55 lbs/agri. acre– pesticides (Oregon: 16 million lbs./yr.)

• works out to 5.3 lbs/capita• Production farmers a minority(we are removed from our food production source and have no idea of food production impact on our economy and environment)

Oregon’s Agriculture• 38,600 (previous 39,300) farms

– Average size = 435 acres– $ output ca. 4.1 billion dollars (annually)

Greenhouse & nursery ($732 m)Cattle & calves ($420 m)Dairy products ($308 m)Grass seed ($322 m)Hay ($464 m)

Top five commodities ($)

U.S. Pesticide Use• 975,000,000 pounds/yr

– ca. 3 pounds per American• U.S. accounts for 20% of world pesticide

use– Ca. $12,000,000,000 per annum

• Pesticide Class Usage– Herbicides 40%– Insecticides 26%– Fungicides 9%– Other 25%

What makes an insect a pest??

It is in conflict with human interests

– In growing plants (our food)– In storing food products– As vectors of disease

• (for both us and our animals.)

What makes an insect a pest??

• Ecosystem simplification– Monoculture:

= reduction in system components = ecological instability.

• Transportation– ease of movement of insects worldwide, both

intentionally and inadvertently. • Human attitudes

– what makes a weed??

Insect Competitors

• Joel 1: 4“What the palmer-worm left, the locust

ate; and that what the locust left, the canker-worm ate, and what the canker-worm left, the caterpillar ate.”

Corn Pests

Putative Amer-Indian homily“One for the bugone for the crow

one to rotand

two to grow”

•That’s 20% insect damage!!! Corn rootworm

Bring on the Insects!!!• How many pest insects are there??• U.S.

–150 to 200 species that frequently cause serious damage

–400 to 500 species that may cause serious damage from time to time

–6,000 species that cause minor damage on an infrequent basis.

• Compare this to the 91,000 insect species known in North America (0.02-0.8% pests)

Corn Pests

• 85,000,000 acres planted in the U.S.– value of about $5,000,000,000– hybrid seed corn market alone is 2 billion $

• Corn Insect Pests– 7 major– 18 minor

• Insect Damage– $900,000,000 per annum– ca. 18% of crop value

Agriculture Pests (the bug kinds)

• Cotton– 125 identified insect pests– FIVE of which are major

• Apples– 400 cataloged pests– Twenty-five of which are

of economic importance.

What does this have to do with the economy?

• V.G. Dethier from his book Man’s Plague– “Farming is ‘big business.’ Its

principal product is money; food is a by-product.”

– “The insect does not compete with our bellies; he competes with our pocketbooks.”

Final Thoughts

• N.E. Borlaug {plant geneticist - founder of the Green Revolution - Nobel laureate}

• “It is as simple a matter as this. We can either use pesticides and fertilizers at our disposal or (we can) starve.”

Final Thoughts

Zilberman et al. (1991) - Science– “Without substitutes, pesticide

bans result in reduced production levels and higher prices;

a substantial loss of discretionary income to consumers and a redistribution of income among agricultural producers.”

Key Points: Insects & Agriculture: Where’s the problem?

• What are the limitations of the wheat, rice and corn paradigms• What is the function of the clonal repositories• How important are pest insects in world food

production• What are the attributes/problems of 1st world ag.?• How will the loss of pesticides affect our economy?