application of radiation sources in agriculture

IAEA International Atomic Energy Agency

Application of Radiation Sources in

Agriculture

Day 6 – Lecture 6

IAEA 2

To learn about the use of ionization radiation in

Agriculture to improve the quality and yield of

crops and fruits and their preservation

Objective

IAEA 3

Contents

Crop Improvement by Mutation

Insect Control

Food Preservation

Fertilizers

Water Resources

Animal Production and Health

.

IAEA 4

Food & Agriculture

A billion people go to bed hungry every night and tens of

thousands die daily from hunger and hunger related

causes. Radioisotopes and radiation used in food and

agriculture are helping to reduce these tragic figures.

IAEA 5

Crop improvement by mutation

techniques

• Ionising radiation is used in plant breeding to produce

new genetic lines. Some examples have been sorghum,

garlic, wheat, bananas, beans, avocado and peppers.

The new lines are more resistant to pests and more

adaptable to harsh climatic conditions.

Genetic Variability

IAEA 6


techniques (Cont.)

• Radiation can cause genetic changes in living organisms

and increase mutation rate up to 1×10-5 ~ 1×10-2

• Induced mutation is useful for crop improvement

Induced Mutation: mutation that is produced by treatment

with a physical or chemical agent that affects the

deoxyribonucleic acid molecules of a living organism.

• Induced mutants are not GMOs (Genetically Modified

Food), as there is no introduction of foreign hereditary

material into induced mutants.

Technical basis

IAEA 7

- Higher yielding

- Disease-resistance

- Well-adapted

- Better nutrition

Mutant cultivars


techniques (Cont.)

no mutation

negative

mutation

IAEA 8

- Improving crop cultivars

- Enhancing biodiversity

- Increasing farmer’s income

Crop improvement by

mutation techniques (Cont.)

IAEA International Atomic Energy Agency

VND99-3

High quality for export

Short duration (100 days)

3 rice harvests per year in the

Mekong Delta

8 new high quality rice mutant

varieties have been developed

and adopted by farmers in

Vietnam, where rice export is one

of their main revenues.

VND95-20

High quality

Tolerance to salinity

Key rice variety for export

“National Prize of Science and

Technology of Viet Nam 2005” for

its “significant socio-economic

contribution”

IAEA 10

• While some insects are important for maintaining

the natural ecological balance, others destroy

valuable food crops. Some insects such as the

mosquito and tsetse fly are vectors of infectious

diseases. It has been estimated that, for the world

as a whole, crop losses caused by insects may

amount to as much as 10 per cent of the total

harvest, an amount equal to the total harvest of a

country such as the USA or the USSR.

Insect Pest Control by Sterile Insect

Techniques (SIT)

IAEA 11

• The Sterile Insect Technique (SIT) consists of

irradiating laboratory-reared male insects before

hatching to sterilise them then releasing them in

large numbers in the infested areas. When they

mate with females, no offspring are produced.

With repeated releases of sterilised males, the

population of the insect pest in a given area is

drastically reduced.


Techniques (Cont.)

IAEA 12

• Radiation is used to induce lethal mutations in chromosomes of insect pests to cause sterility.

• Sterile males are released into the wild where they compete with wild males for matings with wild females.

• SIT relies on: • mass production of the target pest

• sterilization and shipment

• In-undative releases mostly by air

• matings result in no offspring

• SIT integrated with other pest control methods is applied for suppression, containment, or even eradication.


Techniques (Cont.)

Technical basis

Gamma Radiation

No

Offspring

(BIRTH CONTROL)

Insect Pest Control by SIT

Sterile

Sterile

Wild

IAEA 14


Techniques (Cont.)

Few Examples:

• The first successful SIT application was made on the

screw-worm fly, a troublesome pest that lives in the wounds

of warm-bodied animals, particularly livestock. Male screw-

worm flies were reared and sterilized by radiation and

released on the Caribbean island of Curacao. Within a few

breeding cycles, the pest virtually disappeared from this

island.

• Later SIT used to control the screw-worm fly in Florida,

where cattle losses due to that fly had reached a figure of

more than 25 million US dollars a year.

IAEA 15


Techniques (Cont.)

• A great research effort was made into the

Mediterranean fruit fly, which proved to be another

success in Capri and other islands Recently, an

isolated pocket of Mediterranean fruit fly infestation

was eradicated in California by first using

insecticides followed by SIT and the method is now

being used in Central America on a large scale

with support from the Joint FAO/IAEA Division and

its Laboratory. The melon fruit fly was similarly

eradicated from the island of Rota in the South

Pacific.

IAEA 16

Food and Irradiation

• In a hungry world, it is too great a luxury to lose 25 to 30

per cent of the harvested foods to spoilage by microbes

and pests. What is even more regrettable is that these

losses are largest in developing countries. Often an

extension of shelf life of certain foods (i.e. fish and fruit) of a

few days is enough to save them from spoiling.

• More than 25 years have passed since radiation was found

to be applicable to extend the shelf life of certain foods.

Since then, great efforts have been made to test the

wholesome-ness of radiation-processed food In the 25

years of testing such foods, no harmful effects to animals or

humans have been found.

IAEA 17

Food and Irradiation (Cont.)

Food Preservation

25-30% of food lost due to spoilage and pests

irradiation technology can be used to preserve food

More than 40 countries have approved food irradiation

(spices, grains, grain products, fruit, vegetables and meat)

IAEA 18


Food Preservation

astronauts eat foods preserved by irradiation

worldwide standard adopted in 1983

concerns about food-borne diseases and international

trade in foodstuffs

Radiation also used to sterilise food packaging (milk

cartons)

IAEA 19


• Food irradiation is the

treatment of food by

ionizing radiation

• Radiation at appropriate

doses can kill harmful

pests, bacteria, or

parasites, and extend

shelf-life of foods

Technical basis

IAEA 20

Several energy sources

can be used to irradiate

food

• Gamma Rays

• Electron Beams

• X-rays


IAEA 21


• The choice of a irradiator facility and radiation source depends on some practical aspects of the treatment process viz. required absorbed dose, material thickness (bulk product), processing rate etc.

• Capital and Operating costs and also the availability of the technology/ back up etc.

Choice

IAEA 22

Effects of various doses on food

Dosage level

• Low dose(1kGy)

• Medium dose(1-10kGy)

• High dose(10-50kGy)

Effects

• Sprout inhibition

• Delay ripening

• Insect disinfestations

• Reduction of pathogenic

microorganisms

• Reduction of spoilage

microorganisms

• Delay ripening

• Sterilization

• Functional modification

IAEA 23

Food Irradiation

Codex General Standard for

Irradiated Foods

ENSURE FOOD

HYGIENE

OVERCOME

QUARANTINE

BARRIERS

FOOD

SAFETY TRADE

MEAT SHRIMP

CHICKEN

GRAPES

MANGOS

ORANGES CUT FLOWERS SPICES

IAEA 24

'labeled' with a radioactive isotope, such as 15N and 32P, provide a means of finding out how much is taken

up by the plant and how much is lost.

Fertilizers

IAEA 25

31P

14N

32P

15N

31P

14N

13CO2

12CO2

13C 12C

18O 16O

31P

32P

13CO2

12CO2

16O

18O

Fertilizers (Cont.)

IAEA 26

Fertilizers (Cont.)

Few Examples: In one country that took part in a research programme on

nitrogen fertilization of maize, which was organized by the

Joint FAO/IAEA Division, it was estimated that the benefit to

that country amounted to 36 million US dollars per year after

its farmers had adopted the findings of the research

programme for the most efficient placement of fertilizer.

In a similar programme involving coconut palms in Sri

Lanka, it was found that the efficient use of fertilizer not only

yielded direct savings in the cost of fertilizer but also an

estimated potential saving in production cost.

IAEA 27

Fertilizers (Cont.)

Similar programmes on crops such as rice

have yielded savings of millions of dollars in

decreased fertilizer costs. Additional savings

are also possible.

A group of experts recently estimated that

up to 50 per cent of the fertilizer used at

present in all countries could be saved by

improved fertilizer, better water management

and better cropping methods.

IAEA 28

Water Resources

radioactive liquid tracers injected into water supply

underground - trace and measure the extent of

underground water, provide information about origin, age

and distribution and the interconnections between

ground/surface water and renewal systems

surface - evaluate leakage through dams, dynamics of

lakes and reservoirs, flow rates, river discharge

measurements, sedimentation rates

IAEA 29

Animal Production And Health

• In many regions of the world animal production is

limited by poor growth, reproductive performance

and milk output of livestock, which limits the

availability of animal products such as meat, milk,

eggs, fibres, leather, etc. for use by man. Reduced

animal production results from inadequate or

unbalanced nutrition, lack of adaptation to the

prevailing climatic conditions, and parasitic and

other diseases.

IAEA 30

Animal Production And Health (Cont.)

• Coordinated research programmes on the study of non-

protein nitrogen metabolism using N-15 and the utilization

of low quality roughages and agro-industrial by-products in

ruminants, together with studies on mineral imbalances, are

helping to devise alternative feeding practices in countries

where traditional feeds for ruminants are in short supply.

• A programme in which radio-immunoassay techniques are

used to measure the hormonal changes during the

reproductive cycle of cattle and buffalo is leading to

enhanced reproductive efficiency through better

management practices and more efficient use of artificial

breeding techniques

IAEA 31

Animal Production And Health (Cont.)

• A major limitation to increased production is that caused by

parasitic and other diseases. Isotope techniques are not

only providing a well-defined picture of the effect that

parasites have on hosts but are also illustrating how

management and genotypes (breeds and species) can be

modified to reduce the effect of the parasite or disease on

production. Ionizing radiation has been successfully used to

produce an attenuated vaccine against lungworm in cattle

and sheep and this technology is being transferred to those

areas of the world where control of this parasitic disease is

of economic importance, e.g. Brazil, India, Ethiopia.

application of radiation sources in agriculture

Documents