HYBRID: cross
between two different plant varieties to get the valued attributes of each
variety. Hybrids are developed for disease resistance, size, flowering, color,
taste and any reason a plant might be
FOOD SECURITY: the
state of having reliable access to a sufficient quantity of affordable,
nutritious food
HISTORY OF HYBRID DEVELOPMENT
•
Hayes and Jones (1916) first exploited hybrid
vigor or heterosis in cucumber.
•
Commercial hybridization began in US in middle
of 1920s for Sweet Corn and then in 1940s for Onions.
•
Since that time private seed companies are
putting more emphasis for the development of vegetable hybrids.
•
Now many of the vegetable species have been
changed to hybrid for marketing.
FOOD SCENERIO OF WORLD
•
Globally malnourished people in the world exceed
2-3 billion (FAO, 2009)
•
Consumption of vegetable is less than 200 g/person/day
in most of the countries of world.
•
Required 280 g/person/day. Consumption in
Pakistan is 140 g/person/day.
•
Poor consumption of vegetable is often in
conjunction with poverty and availability of vegetables.
•
There were 392 vegetable crops cultivated
throughout the world.
•
From last few decades slightly over half of them
attracted commercial breeding.
•
Almost half of vegetable growing farmers of the
world are poor and cannot afford to buy expensive hybrid seed every year.
•
Population of world is increasing consistently
and to cope this situation increase in quantity and quality of food is needed.
WHAT ARE HYBRIDS
•
Produced by cross pollinating two inbreds
generally having monoecious, complete or incomplete flowers.
•
The seed produced from cross pollinating plants
are hybrid seeds (F0).
•
The crop raised from hybrid seeds is hybrid
crop(F1).
•
Maximum vigor is exploited due to crossing of
diverse inbreds.
TYPES OF HYBRIDS
•
SINGLE CROSS HYBRID
•
THREE- WAY CROSS HYBRID
•
DOUBLE CROSS HYBRID
•
TOP CROSS HYBRID
MAJOR
VEGETABLE HYBRID PRODUCING COUNTRIES
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•
China
•
India
•
USA
•
Japan
•
Italy
•
Spain
•
Egypt
•
Mexico
•
Thailand
ADVANTAGES OF
HYBRIDS
•
Higher harvests index per unit area.
•
Often hardier, more resistant to pest and
disease.
•
Variety of hybrids available, with unique
properties and uses.
•
Uniform harvest time.
•
Uniform produce
DISADVANTAGES
OF HYBRIDS
- Hybrids (F1)seeds are costly as compared to seed of OPV’S
- Hybrid seed is only for one crop season, if the seed is planted in the next year (F2) different type of plant attained due to maximum segregation by default.
- Hybrids are generally specific to the first producer and have to purchase from same source to get desirable results.
- Hybrids cannot be retained as germplasm as converse to OPV’S.
- Hybrids need to be replaced over short period of time due to competition in the market.
HYBRID VEGETABLE SEED/CROP AND
ITS SIGNIFICANCE IN FOOD SECURITY
- The horizontal space is decreasing throughout the world due to urbanization and competition with other food crops therefore for food security following parameters should be met:
- Healthy, bold, vigorous seed with high germination percentage.
- Crop stand should be high and uniform.
- Highly responsive to inputs.
- The seed should be at affordable level of the farmers for its wider adaptability to successfully fight against hunger.
- The yield should be higher at least 50-75 percent as compared to existing OPV’S.
- 7. Must be competitive in the market for quality.
- Should be of high value for more return to the
- Farmers.
- Should add in the supply period of the existing OPV’S.
- Can fight different abiotic and biotic stresses.
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DIFFERENT STRATEGIES ADOPTED TO ADD IN FOOD SECURITY
STRATEGIES
- Control of Apomixis would enable the fixation of hybrid vigor and the development of true-breeding hybrids in a particular breeding program. Seed could be produced for many generations without loss of vigor or genotype alteration.
2. Apomixis could simply be viewed as a threat
to the current viability of hybrid seed companies because farmers could process
and plant their own seeds
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