Horizontal resistance
Encyclopedia
In genetics
, the term horizontal resistance was first used by J.E. Vanderplank to describe many-gene resistance. This contrasts with the term vertical resistance
which was used to describe single-gene resistance. Raoul A. Robinson
further refined the definition of horizontal resistance. Unlike vertical resistance
and parasitic ability, horizontal resistance and horizontal parasitic ability are entirely independent of each other in genetic terms.
In the first round of breeding for horizontal resistance, plants are exposed to pathogens and selected for partial resistance. Plants unaffected by the pathogen have vertical resistance and are removed. Obviously plants with no resistance die, the remaining plants have partial resistance and their seed is stored and bred back up to sufficient volume for further testing. The hope is that in these remaining plants are multiple types of partially resistant genes, and by crossbreeding this pool back on itself multiple partial resistance genes will be encouraged and provide resistance to a larger variety of pathogens than vertical resistance
.
Successive rounds of breeding for horizontal resistance proceed in a more traditional fashion, selecting plants for disease resistance as measured by yield. These plants are exposed to native regional pathogens, and given minimal assistance in fighting them.
Genetics
Genetics , a discipline of biology, is the science of genes, heredity, and variation in living organisms....
, the term horizontal resistance was first used by J.E. Vanderplank to describe many-gene resistance. This contrasts with the term vertical resistance
Vertical resistance
The term vertical resistance was first used by J.E. Vanderplank to describe single-gene resistance. This contrasted the term horizontal resistance which was used to describe many-gene resistance. Raoul A...
which was used to describe single-gene resistance. Raoul A. Robinson
Raoul A Robinson
Raoul A. Robinson is aCanadian/British plant scientist with more than forty years of wide-ranging global experience in crop improvement for both commercial and subsistence agriculture...
further refined the definition of horizontal resistance. Unlike vertical resistance
Vertical resistance
The term vertical resistance was first used by J.E. Vanderplank to describe single-gene resistance. This contrasted the term horizontal resistance which was used to describe many-gene resistance. Raoul A...
and parasitic ability, horizontal resistance and horizontal parasitic ability are entirely independent of each other in genetic terms.
In the first round of breeding for horizontal resistance, plants are exposed to pathogens and selected for partial resistance. Plants unaffected by the pathogen have vertical resistance and are removed. Obviously plants with no resistance die, the remaining plants have partial resistance and their seed is stored and bred back up to sufficient volume for further testing. The hope is that in these remaining plants are multiple types of partially resistant genes, and by crossbreeding this pool back on itself multiple partial resistance genes will be encouraged and provide resistance to a larger variety of pathogens than vertical resistance
Vertical resistance
The term vertical resistance was first used by J.E. Vanderplank to describe single-gene resistance. This contrasted the term horizontal resistance which was used to describe many-gene resistance. Raoul A...
.
Successive rounds of breeding for horizontal resistance proceed in a more traditional fashion, selecting plants for disease resistance as measured by yield. These plants are exposed to native regional pathogens, and given minimal assistance in fighting them.