In plant breeding programmes, the entire collection (of plants/seeds) having all the diverse alleles for all genes in a given crop is called :

1. cross-hybridisation among the selected parents.
2. evaluation and selection of parents.
3. germplasm collection.
4. selection of superior recombinants.

The reason why vegetatively reproducing crop plants are best suited for maintaining hybrid vigor is that          (CBSE-PMT 1998)
1. They can be easily propagated.
2. They have a longer life pan.
3. They are more resistant to diseases.
4. Once a desired hybrid is produced, there are no chances of losing it.

 

The world’s highly prized wool yielding Pashmina breed is  
1. Kashmir sheep - Afgan sheep cross.
2. Goat
3. Sheep
4. Goat - sheep cross 

The name of Norman Borlaug is associated with  
1. Green revolution
2. White revolution
3. Yellow revolution
4. Blue revolution 

Three crops that contribute maximum to global food grain production are                  
1. wheat , rice and maize
2. Rice, maize and sorghum
3. Wheat, maize and sorghum
4. Wheat, rice and barley 

Why is vivipary an undesirable character for annual crop plants
1. It reduces the vigor of the plant.
2. The seeds exhibit long dormancy.
3. It adversely affects the fertility of the plant.
4. The seeds cannot be stored under normal conditions for next season.

 

Triticale, the first man-made cereal, has been obtained by crossing wheat with        
1. Rye
2. Pearl millet
3. Sugarcane
4. Barley 

Crop plants grown in monoculture are 

1. Low in yield.
2. Free from intraspecific competition.
3. Characterized by poor root system.
4. Highly prone to pests.

In order to obtain virus-free plants through tissue culture the best method is                  
1. protoplast culture
2. embryo rescue
3. anther culture
4. meristem culture 

In maize, hybrid vigor is exploited by      
1. bombarding the protoplast with DNA
2. crossing of two inbred parental lines
3. harvesting seeds from the most productive plants
4. inducing mutations