Plant Genetic Resources for Food and Agriculture

CHAPTER 4 GENETIC RESOURCES IN AGRICULTURE

GENETIC RESOURCES

• Genetic resources (GRs) refer to genetic material of actual or potential value.
  
• Genetic material is any material of plant, animal, microbial or other origin containing functional units of heredity.
  
• Examples include material of plant, animal or microbial origin, such as  medicinal plants, agriculture crops and animal breeds.

Animals Genetic Resources

Plant Genetic Resources and Seeds

Collection of genetic resources called Germplasm.

Germplasm

• A collection of genetic resources for an organism.
  
• Germplasm is the living genetic resources such as seeds or tissue that is maintained for the purpose of animal and plant breeding, preservation, and other research uses.
  
• Germplasm collections can range from collections of wild species to elite, domesticated breeding lines that have undergone extensive human selection.

The National Germplasm Resources Lab facilitates the acquisition, exchange, and documentation of crop genetic resources important to world food security.

What is Biodiversity?

• Biodiversity is the variety of different types of life found on Earth and the variations within species.
  
• Within species or between species.

• The number and variety of plants, animals and other organisms that exist is known as biodiversity.

• Biodiversity is not evenly distributed; rather it varies greatly across the globe as well as within regions. Among other factors, the diversity of all living things (biota) depends on temperature, precipitation, altitude, soils, geography and the presence of other species. The study of the spatial distribution of organisms, species, and ecosystems, is the science of bio geography.

         There are 3 categories of Biodiversity.
         1. Ecosystem Diversity
         2. Species Diversity
         3. Genetic Diversity

               ECOSYSTEM DIVERSITY

• Different diversity in variety of habitats, topography, elevation, natural vs agro ecosystem.
• Refers to the variety of ecosystems in a given place.
• Within any broader landscape there is a mosaic of interconnected ecosystems.

              SPECIES DIVERSITY

• the number of different species that are represented in a given community (a dataset).
• defined as the number of species and abundance of each species that live in a particular location.
• There are numerous reasons why species diversity is essential. Each species has a role in the ecosystem.

• For example, bees are primary pollinators. Imagine what would happen if bees went extinct. Fruits and vegetables could be next, and subsequently the animals that feed off them - this chain links all the way to humans.
  
• Various species provide us not only with food but also contribute to clean water, breathable air, fertile soils, climate stability, pollution absorption, building materials for our homes, prevention of disease outbreaks, medicinal resources, and more.

               GENETIC DIVERSITY

• Genetic diversity refers to the diversity (or genetic variability) within species.
• Genetic diversity is the sum of genetic information contained in the genes of individual plants, animals, and micro-organisms.
• What is the significance of genetic diversity?
• The huge variety of different gene sets also define an individual or a whole population's ability to tolerate stress from any given environmental factor.

Genetic diversity in a species allows it to adapt to changing environments.

CHAPTER 3 AGRO-ECOLOGICAL SYSTEM

HUMAN RESOURCES

Agriculture cannot operate without workforce:-

scientists - a person who is trained in a science and whose job involves doing scientific research or solving scientific problems

teaching institutions of agriculture - teaching, research and services to find the right balance between agricultural production and long-term environmental sustainability

supporting specialists - scientific research and new knowledge to agricultural practices through farmer education

skilled operators - agriculture involves human labour

IMPACT OF CLIMATIC CHANGE

global warming - almost 100% of the observed temperature increase over the last 50 years has been due to the increase in the atmosphere of greenhouse gas concentrations like water vapour, carbon dioxide (CO2), methane and ozone. Greenhouse gases are those gases that contribute to the greenhouse effect. The largest contributing source of greenhouse gas is the burning of fossil fuels leading to the emission of carbon dioxide

desertification - persistent degradation of dryland ecosystems. It threatens the livelihoods of some of the poorest and most vulnerable populations on the planet. Desertification is largely caused by unsustainable use of scarce resources

IMPACT OF POLLUTION

acid rain - both natural and man-made sources are known to play a role in the formation of acid rain. But, it is mainly caused by combustion of fossil fuels which results in emissions of sulfur dioxide (SO2) and nitrogen oxides (NOx). Aquatic settings are the most clearly impacted by acid deposition though because acidic precipitation falls directly into them. Both dry and wet deposition also runs off of forests, fields, and roads and flows into lakes, rivers, and streams.

heavy metals - heavy metals are natural constituents of the earth's crust, but indiscriminate human activities have drastically altered their geochemical cycles and biochemical balance. This results in accumulation of metals in plant parts having secondary metabolites, which is responsible for a particular pharmacological activity. Prolonged exposure to heavy metals such as cadmium, copper, lead, nickel, and zinc can cause deleterious health effects in humans. Molecular understanding of plant metal accumulation has numerous biotechnological implications also, the long term effects of which might not be yet known

chemical pesticide - pesticides are designed to kill and because their mode of action is not specific to one species, they often kill or harm organisms other than pests, including humans. Pesticide exposure can cause a range of neurological health effects such as memory loss, loss of coordination, reduced speed of response to stimuli, reduced visual ability, altered or uncontrollable mood and general behavior, and reduced motor skills. These symptoms are often very subtle and may not be recognized by the medical community as a clinical effect. Other possible health effects include asthma, allergies, and hypersensitivity, and pesticide exposure is also linked with cancer, hormone disruption and problems with reproduction and fetal development

eutrophication - eutrophication is most often the result of human activity. Farms, golf courses, lawns and other fields tend to be heavily fertilized by people. Eutrophication can have serious, long-term effects. The most notable effect of eutrophication is algal blooms. When a bloom occurs, the stream, river, lake or ocean becomes covered with algae, which is usually bright green. In addition to looking pretty ugly

About GMOs