A Comparison of the Various Features of Vertical and Horizontal Disease Resistance

1

Phenotype-specificity

Specific

Nonspecific

2

Nature of gene action

Oigogenic

Polygenic, rarely Oigogenic

3

Response to pathogen

Usually, hypersensitive

Resistant response

4

Phenotypic expression

Qualitative

Quantitative

5

Stages of expression

Seedling to maturity

Expression increases as plant matures

6

Selection and evaluation Risk of boom and bust suitable for 1. Host, 2. Pathogen

Relatively easy present (rarely durable)

Relatively difficult absent ( durable)

7

Need for specific development of resistant varieties

Critical for success with mobile pathogen

None

8

Need for other control measures

likely

Much less likely

9

Host pathogen interaction

Present

Absent

10

Commonly used , but not strict synonyms

Major gene, race-specific, seedling, monogenic, differential, specific, Pathotypes- specific resistance.

Polygenic, race non specific , Pathotypes- nonspecific , mature plant, adult plant, field, uniform resistance

11

Efficiency

Highly efficient against specific races

Variable but operates against all races.