Question

To obtain disease resistant strains, hybridisation programmers are carried out with

• A. Mutant varieties
• B. Wild varieties
• C. Emasculated plants
• D. Cultivated plants

Answer 1

Answer: (B)

In biology a hybrid is mix of two animals or plants of different breeds, varieties, species or genera. Hybrids are genetically superior varieties of the existing wild varieties. Many hybrids are created by humans, but natural hybrids occur as well.

Some host genotypes possess the ability to prevent a pathogen strain from producing disease. Such host lines are called resistant, and this ability is called resistance or disease resistance. The term strain has a similar meaning for the pathogen as line has for the host.

Those lines of a host that are not resistant to the pathogen are called as susceptible.

A successful breeding for disease resistance depends mainly on the following two factors: (i) a good source of resistance, and (ii) a dependable disease test.

Sources of resistance genes may be cultivated varieties, germplasm collections of the crop or wild relatives of the crop.